News for the Solar Manufacturing Industry
Volume 2 Number 6 November/December 2009
Brice Le Gouic Interview Inside Silicon solar cell efficiency & thermal process optimization in the metallization process Making I‑V and C‑V measurements on solar/photovoltaicSolar simulators— beyond Class A
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Volume 2, No. 6 November/December 2009
Rotary or in-line—make your choice Trevor Galbraith
Silicon solar cell efficiency & thermal process optimization in the metallization process Dean Buzby, Heraeus Materials Technology and Bjorn Dahle, KIC
10 Making I‑V and C‑V measurements on solar/photovoltaic Josef W. Flossmann, Keithley Instruments GmbH
22 28 30 32
Interview—Brice Le Gouic, Yole Développement The dream lives on, but business slow at the 24th EUPVSEC Solar hogs the limelight at 3rd Renewable Energy India 2009 Expo Solar Power powers ahead
16 Taiwan resumes growth in solar manufacturing Jon Custer-Topai Regular Features
4 24 34 48
Industry News Technological Developments New Products International Diary
Visit the website for more news & content: www.globalsolartechnology.com.
Researchers at the University of Texas at Austin apply nanoparticle “inks” as a spray on solar cells (page 24).
Global Solar Technology – November/December 2009 – 1
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Editor-in-Chief, Global Solar Technology
Rotary or in-line—make your choice Printers were definitely at the forefront of new innovations at EU PVSEC this year. Asys and Applied Materials (Bacinni) had new rotary printers out that increased speed, had smaller footprints and performed both print on print and selective emitter. Meanwhile, across on the DEK booth, they were unveiling their PV3000 in-line system. I have to confess being a little skeptical when DEK first launched into the PV industry with the PV1200, as it seemed to depart from the industry norm. Everybody was used to the rotary platform, and for a newcomer to design such a radically different machine seemed rather cheeky. However, it started to make sense when we saw the new PV3000 machine. Essentially, it is a three-lane version of the single lane. Wafers are fed-in from three parallel loaders onto a conveyor along the back of the machine. The wafers are then indexed onto the print platform, printed, then indexed onto the exiting conveyor, past a paste inspection unit. The printed wafers are then served onto a threelane conveyor that transports them through the drier. All this is accomplished in under 17 meters, including the drier. However, the real sweet spot of the system, apart from the speed, is the ability to stop one print head for maintenance or cleaning, without the need to interrupt production on the other two heads. The PV3000 also does print on print and selective emitter. Print on print is novel technique to reduce shadowing of the printed finger, while maximizing the height of the paste deposit and the amount of energy it can conduct. Typically, a printer will print an 80 µm line, then print another 50 µm line on top of it.
Asia/Pacific Print - Debasish Choudhury Tel: +91 120 6453260 email@example.com
2 – Global Solar Technology – November/December 2009
Selective emitter technology features a relatively low surface doping concentration everywhere on the surface of the cell, except directly beneath the metal grid. This means low contact resistance, due to the heavy doping under the grid, and improved front-surface passivation in the areas between the grid. A selective emitter has, in the past, been difficult to achieve with screen printing, but that is changing. Today, the majority of cell manufacturers opt for turnkey lines. With the fast pace of technology and the potential to maximize yields and efficiencies by optimizing the process, it surely won’t be long before manufacturers start moving en masse towards best-in-class equipment.
Polysilicon and solar cell image courtesy Schott.
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Heraeus Materials Technology LLC Photovoltaic Group West Conshohocken, PA 19428 USA +1 610-825-6050 www.pvsilverpaste.com firstname.lastname@example.org
Industry news Title
Industry news Indium Corporation acquires assets of Reactive NanoTechnologies Indium Corporation acquired the processes, equipment and know-how of Reactive NanoTechnologies Inc. (RNT), developer and manufacturer of NanoFoil®. Indium will move the RNT process and equipment, and a core staff, into its Utica Business Park (Utica, New York) facility. There will be minimal disruption in the RNT business operation as integration activities have already been underway. Customers will now place their orders and inquires directly through Indium Corporation. The core RNT team, along with Indium Corporation personnel, will continue supporting the NanoFoil® and NanoBond® business. www.rntfoil.com, www.indium.com Solar cells see record shipments in April-June quarter Shipments of solar power generation cells increased 82.5 percent during the April-June quarter compared with the same period the previous year to reach a record high, figures released by the Japan Photovoltaic Energy Association have shown. The quarter saw shipments of solar cells with a total generating capacity of 83,260 kilowatts, a record high for a quarter. Over 90 percent of the shipments were for residences, with the total amount being enough to power about 2,000 average-sized homes. This year the government and local bodies have implemented subsidy systems for the introduction of solar power generation, and the decrease in installation costs has spurred demand for home use. [Source: Mainichi Japan] RNCOS report highlights increasing demand and global momentum for growth of solar market Independent market researcher RNCOS projects that installed photovoltaic capacity will grow at a compound annual rate of approximately 28 percent from now to 2013. In a new report, RNCOS forecasts that the impact of policy and investment support from Europe, the U.S. and Asia, in combination with improved technologies that are reducing the cost of PV production, will spur the continued growth of solar at an extraordinary rate.
Pike Research also sees mounting growth, predicting that the U.S. solar market will surpass major European nations in the next 1-4 years, also due to technological advances and solar-friendly government policies and subsidies. The overwhelming majority of photovoltaic cells currently in use are on-grid—that is, they are connected to existing utility company infrastructure— but RNCOS expects that demand for off-grid (generally rural electrification) and consumer applications will explode. Access the RNCOS report “Global Photovoltaic Market Forecast to 2013” here: www.rncos.com/Report/IM203.htm. Hoku Materials granted foreign trade zone status by U.S. Commerce Department Hoku Materials, Inc., a wholly owned subsidiary of Hoku Scientific, Inc. established to manufacture and sell polysilicon for the solar market, has been granted foreign-trade zone (FTZ) subzone status by the United States Department of Commerce for its polysilicon manufacturing plant currently under development in Pocatello, Idaho. The ruling allows Hoku to import foreignsourced raw materials in a duty-free status, provided they are destined for export overseas as components of finished polysilicon. Under its existing customer supply agreements, more than 80% of Hoku’s total annual production capacity of polysilicon, and 100% of what has been presold to date, is destined for export to China, meaning that an equivalent percentage of the company’s raw material inputs would be eligible for import in a duty-free status. Hoku has been granted subzone status under the existing Foreign Trade Zone established for Boundary County in Northern Idaho, the only FTZ in the state. Hoku Materials’ facility will be the only designated Foreign Trade Subzone in Idaho. When complete, the Hoku Materials facility is expected to produce up to 4,000 metric tons of polysilicon per year. www.hokucorp.com IMEC to house Kaneka’s European Photovoltaics Lab advancing joint research European nanoelectronics research center IMEC and Kaneka Corporation,
4 – Global Solar Technology – November/December 2009
a Japanese manufacturer of chemical specialties and solar cells, have announced a bilateral cooperation. Under the agreement, Kaneka will incorporate its European Photovoltaics Laboratory at IMEC in Leuven, Belgium. Working in IMEC’s facilities and collaborating with IMEC’s experts, this will allow Kaneka to further improve its current thin-film solar cells and to develop next generation cells. This agreement fits in the strategy of Kaneka to examine the expansion of its solar cell manufacturing capacity to 1 Giga Watt by 2015. The decision to establish a European lab was motivated by the need to have a presence, and in future also a production facility, close to the rapidly growing European PV market. www.imec.be Russia-based Nano Solar Technology order Oerlikon thin film production line Oerlikon Solar today announced that Nano Solar Technology Ltd. (NST), a newly formed Russian high-tech firm, has ordered a 120 MW end-to-end Micromorph® line for production of thin film solar modules. NST is a joint venture between Renova Group and the Russian Corporation of Nanotechnologies (Rusnano). With the envisaged production capacity of one million solar modules annually, this is the largest equipment order in the worldwide thin film silicon photovoltaic (PV) market in 2009 to-date. The order includes Oerlikon Solar’s Micromorph® technology which raises module efficiency by up to 50 percent over prior generation technologies. The equipment will be delivered in 2010 to the new site currently under construction in Novocheboksarsk (Chuvash Republic). The start of production is scheduled for 2011. www.oerlikon.com/solar
BioSolar files patent for BioBacksheet™ thin film photovoltaic solar module component BioSolar, Inc., recently filed a patent application to protect the innovations behind its proprietary BioBacksheet™-A, a bio-based backsheet featuring an absolute moisture barrier for the thin-film solar cell market. BioBacksheet-A is a three layer laminate film consisting of a 100 percent recyclable aluminum foil center core sandwiched between two outer layers of bio-based polymer films, making it a unique product in the industry. www.biosolar.com Scheuten Solar strengthens its presence in Greece Scheuten Solar has begun supplying Scheuten Multisol® modules for a 1 MWp project in Greece, owned and operated by Ilioependytiki S.A. Data Energy is undertaking the installation of the almost 6,000 Multisol PV panels. This project is presently one of the biggest in Greece and is located between Tripoli and Megalopolis in the southern part of the country. www.scheutensolar.com SunSi Energies signs definitive JV agreement SunSi Energies Hong Kong Ltd, a wholly owned subsidiary of SunSi Energies Inc., has signed a definitive joint venture agreement to form a Trichlorosilane (TCS) production joint venture in Zibo, China. As previously released, SunSi Energies Hong Kong Ltd will own 90% of a new company specifically formed to own the assets, expertise and technology of an existing Trichlorosilane production facility with a current production capacity of 25,000 MT per year. The new company, to be called Zibo Boayun Chemical Company Ltd, will produce TCS, a chemical used in the production of polysilicon, an essential raw material used during the production of solar cells for photovoltaic (PV) panels that convert sunlight to electricity. www.sunsienergies.com CNPV expands product warranties for crystalline solar photovoltaic modules CNPV, a multi-product solar company that produces ingots, wafers, cells & solar modules, recently expanded the product workmanship warranty of their high performance crystalline solar photovoltaic modules to 10 years. The new warranty terms apply to all high performance crystalline solar photovoltaic modules with
delivery date June 1, 2009 or later. www.cnpv-power.com Energy Conversion Devices completes merger with Solar Integrated Technologies Energy Conversion Devices, Inc. (ECD), a manufacturer of thin-film flexible solar laminate products for the building integrated and commercial rooftop markets, has completed its merger with Solar Integrated Technologies, Inc. (SIT), a provider of building integrated photovoltaic (BIPV) roofing systems. SIT is now a wholly owned subsidiary of ECD. www.energyconversiondevices.com, www.solarintegrated.com
Appointments Bakhu Holdings Bakhu Holdings Corp. appointed Xinan Zeng as CEO, replacing Alexander Deshin, founder, CEO and CFO, who has resigned. Mr. Zeng is the chairman and CEO of the company Bakhu plans to merge with, Shenzhen Xinhonglian Solar Energy Co. Cyrium Technologies Cyrium Technologies, Inc., appointed Harry R. Rozakis as CEO & president. Rozakis was most recently CEO Vietnam—Chipscale Advanced Packaging Services. First Solar Robert J. Gillette has been appointed CEO of First Solar, Inc., succeeding Mike Ahearn. Gillette has spent the last four and a half years as the CEO and president of Honeywell Aerospace. General Plasma General Plasma Inc. appointed Greg Teesdale as VP of business development.
Sixtron enters Asian Market with order from Top 10 solar cell manufacturer Sixtron Advanced Materials, a provider of safe and efficient silane-free antireflective coatings systems, has secured an evaluation purchase order from a leading Asian solar cell manufacturer for its SunBox gas delivery system. The Sixtron system is a plug-and-play solution that provides cost savings and cell efficiency improvements while reducing downtime. Sixtron’s application specialists will support the production evaluation of the SunBox system with the new customer to achieve system optimization and ensure seamless integration into existing and new manufacturing lines. www.sixtron.com
Continued on page 38
Konarka Alex Valenzuela joined Konarka Technologies, Inc. as VP of European business development. Alex was previously regional manager at United Solar Ovonic. Magnolia Solar Dr. Roger E. Welser joined Magnolia Solar as CTO. Solar Power Partners Phil Henson joined the Solar Power Partners, Inc., executive team as VP and CFO. Hugh Kuhn, SPP’s vice president of operations and technology, has been named Sr VP and COO. Sustainable Energy Sustainable Energy Technologies Ltd appointed Robert H. Bucher president and CEO. Bucher’s industry experience includes tenures as CEO of Adept Technology and CEO of Norsat International.
Global Solar Technology – May/June 2009 – 5
Silicon solar cell efficiency & thermal process optimization in the metallization process
Silicon solar cell efficiency & thermal process optimization in the metallization process by Dean Buzby, Heraeus Materials Technology, Chandler, Arizona, USA, and Bjorn Dahle, KIC, San Diego, California, USA The solar industry’s drive toward lower cost per W requires both lower cost as well as higher solar cell efficiency. The relationship between an optimized thermal process and increased cell efficiency has long been known, although the quantification of this relationship and the method to achieve it have been less well understood. This article outlines the method of process optimization, and it measures the resulting cell efficiency improvements as they relate to volume production of solar cells. The basic strategy used is applicable for a variety of thermal processes, both within the silicon as well as thin film solar cell manufacturing. This article, however, focuses on the silicon solar cell metallization process.
Experiment overview As a manufacturer of silver pastes for solar cell applications, Heraeus has worked on perfecting its material’s performance in the metallization process for some time. A design of experiment using KIC’s e-Clipse thermocouple (TC) attachment fixture was developed to use more sophisticated thermal profiling and process optimization tools to help identify the very best wafer profile for the company’s latest paste and to measure what impact such process optimization would have on cell efficiency. A number of identical wafers were processed in a metallization furnace under different thermal process conditions, and their resulting cell efficiency improvements were measured. The results are presented in this article. Cell metallization For solar cell metallization applications, thick film paste is a suspension of a functional (conductive) phase, binder, vehicle and additives. Silver is the most common conductive filler used for front contact paste. The binder is composed of a glass
frit that is used to bind the functional phase to the silicon wafer. Specialized chemistry of the binder also is required to etch through anti-reflective and passivation layers, and initiate effective ohmic contact between the silver and silicon. The vehicle is an organic composition that provides printability of the pastes and is composed of resins, solvents, and modifiers. The resins support the solids of the other phases and keep them in homogeneous suspension. Solvents are used to dissolve the resins, and they must be stable in production conditions. These organic components of the paste must burn off cleanly in the fastfiring process so as not to contaminate the surface of the wafers or introduce sources of recombination near the p-n junction. The paste is applied using the standard screen-printing process common to crystalline silicon solar cell production. After printing, the wafers pass through an inline dryer and proceed directly into the firing furnace. Most furnaces today contain six firing zones, but the differences from manufacturers come from the length of the zones and how they maintain a uniform
Keywords: Solar Cell Metallization, Process Optimization, Wafer Profile, Cell Efficiency, Thermal
Figure 1. Heraeus silver paste.
6 – Global Solar Technology – November/December 2009
Silicon solar cell efficiency & thermal process optimization in the metallization process
firing environment within the furnace. The thermal process of the wafer is one of the keys to achieving improved efficiencies. Drying steps are expected to remove most of the solvent used in the pastes before entering the firing zones. Solar cell metallization generally follows a spike profile type. Wafers only see peak temperature for approximately 1-4 seconds based on wafer and metallization chemistries. The most important steps include the clean burnout of the organics in the paste followed by etching through the silicon nitride (or other) passivation/ARC layer and, ultimately, the formation of good ohmic contact between the sintered silver and the very top layer of n-type silicon. These all lead to low contribution from series resistance and recombination resulting from the formation of the contacts. Control of this profile will become more crucial as the emitter depth decreases with increasing sheet resistance. Both uniformity of diffusion and furnace will be necessary to achieve the desired efficiency improvements. Thermal process development Since the hypothesis is that the wafer’s
Figure 2. The wafer profiles for each group.
thermal profile will significantly impact the cell efficiency, an experiment was designed to vary the wafer profiles while keeping all other variables constant:
“The thermal process of the wafer is one of the keys to achieving improved efficiencies.” Wafers: We purchased a large quantity of wafers that were known to be of a very consistent quality Aluminum coating: All the wafers had consistent aluminum coating. Silver paste: The Heraeus paste SOL 9235H was from the same batch consistent. Screen print: Great care was taken when screen printing the Heraeus paste to secure that the paste deposition, line width, and line thickness were uniform across all wafers. Profiling: All profile measurements were taken with a high accuracy thermal profiler that used a new TC attachment fixture that was proven to offer accurate and consistent readings on the surface of the wafer. The type K TCs in the fixture used a flattened disk bead rather than the spherical bead for added accuracy and repeatability Efficiency Testing: The solar simulator was a continuous lamp tester used in all measurements. The base line profile on these wafers had been developed prior to the project based
on extensive knowledge of the paste chemistry and years of practical experience with the metallization process. The base line profile can be seen in dark blue in Figure 2. For the base line test, as with all the subsequent process improvement tests, the wafers were processed at the same time and fired under the same conditions. Ten wafers were run through the furnace within a short period of time, and all were subjected to the same profile. After firing, we measured the cell efficiency in our continuous lamp tester. The average efficiency for the base line profile was 15.53 percent, as can be seen in Figure 3 (η Cell). Based on the type of wafer that was selected for this study, and the fact that a continuous lamp tester was used rather than a flash tester, this efficiency number was considered good. Now we wanted to make it better. It is important to acknowledge that what we were trying to accomplish was not to find a single “golden” profile for the wafers, but rather the optimal thermal process window. The Heraeus paste SOL9235H is a very robust paste that can perform well throughout a range of profiles. Establishing a thermal process window will set the upper and lower limits for the wafer’s peak temperature, time above certain temperature levels, etc. within which the cell efficiencies will be highest. Since we did not yet know the upper and lower limits to our process window, we used the base line profile as a starting point, and we initially set relatively wide process limits around it as shown in Figure 4. The profiler software always measures how well the profile fits the chosen process window with a single number called Process Window Index (PWI). The PWI number is 100 percent when the profile is at the edge of the process window. The lower the number, the closer the profile is to the center of the process window. A PWI of 0 percent represents a profile at the very center of the process window. Our profiler also has profile simulation software that allowed us to change the furnace zone temperatures or conveyor
Group 1 base line
Figure 3. Cell efficiency testing.
Global Solar Technology – November/December 2009 – 7
Silicon solar cell efficiency & thermal process optimization in the metallization process
the average cell efficiency of the 10 wafers dropped by 0.12 percent. For the Group 4 test, we set the zones back to the Group 2 level and reduced the furnace conveyor speed. The prediction software showed the impact on the wafer profile both in terms of peak temperature changes and, in particular, in terms of time above the various temperature levels shown in Figure 5. Due to this, we reduced the conveyor speed from 200 to 190”/ min. The average cell efficiencies increased yet another 0.11 percent above the Group 2 numbers to a cell efficiency of 16.04 percent. Our final test for Group 5 kept the temperatures stable but increased the conveyor speed from 190 to 210”/min. That dropped the average cell efficiency by 0.16 percent. Figure 4. Boxplot of cell efficiencies for base each wafer profile.
Figure 5. Original process window.
Figure 6. e-Clipse TC attachment fixture.
speed in the software, and to immediately predict the resulting wafer profile. For the first process improvement step, we suspected that a higher peak temperature would benefit the metallization. We tried a few zone temperature changes in the software and studied the software simulation of the corresponding profile
before settling on a 10°C increase in the furnace peak zones (Zone 5 and 6). Once the furnace stabilized on the new settings, we ran a set of 10 wafers for our Group 2 test. The average cell efficiency increased from 0.40 to 15.93 percent. For Group 3, we increased the peak temperatures settings in zones 5 and 6 another 10°C, but
8 – Global Solar Technology – November/December 2009
Conclusion By systematically changing certain key profile dimensions, such as peak temperature and time above 500°C, we were able to identify the “sweet spot” in the metallization process. The PWI index and the profiler’s simulation software allowed us to quickly identify the appropriate furnace settings for profiles below, above and in the middle of the optimal settings. This sweet spot yielded an average cell efficiency of 0.51 percent higher than previous experiments had allowed. The Heraeus SOL 9235H silver paste’s properties allow for high-efficiency processing in a range of profiles, hence a process window can be established around the “ideal” profile identified above. Heraeus now advices its clients to the appropriate process window for each application. With modern profilers, solar cell manufacturers can adjust their furnace setup until the wafer profile is positioned within the suggested process window. Over time, the thermal process will drift due to a number of variables such as heating lamps changing as they get older, wear and tear in the furnace, conveyor speed drifts, exhaust changes, and more. It then is a simple task for the manufacturing engineer to run another profile, and to use the profiler process optimization software to identify the furnace settings that will yield the appropriate profile. This method for process optimization depends on accurate and repeatable profile readings. One excessive noise in the profile readings historically has been caused by the attachment method for the TCs. Both cemented and dummy wafer TCs tend to measure the material used to secure the Continued on page 37
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Global Solar Technology – November/December 2009 – 9
Making I‑V and C‑V measurements on solar/photovoltaic
Making I‑V and C‑V measurements on solar/ photovoltaic by Josef W. Flossmann, Keithley Instruments GmbH, Germering, Germany
Because of the increasing demand for energy and the limited supply of fossil fuels, the search for alternative sources of power is imperative. Given that there is a vast amount of energy available from the sun, devices that convert light energy into electrical energy are becoming increasingly important. Solar or photovoltaic (PV) cells convert light energy into useful electrical power. These cells are produced from light-absorbing materials. When the cell is illuminated, optically generated carriers produce an electric current when the cell is connected to a load.
Keywords: I-V Measurements, Forward Bias I-V Measurements, C-V Sweep, C-f Sweep
A variety of measurements are made to determine the electrical characteristics of PV cells. Characterizing the cells often involves measuring the current and capacitance as a function of an applied DC voltage. The measurements are usually done at different light intensities and temperature conditions. Important device parameters can be extracted from the current-voltage (I‑V) and capacitancevoltage (C‑V) measurements, such as the conversion efficiency and the maximum power output. Electrical characterization is also important to determine losses in the PV cell. Essentially, electrical characterization is needed to determine ways to make the cells as efficient as possible with minimal losses. To make these important electrical measurements, using a tool such as the Model 4200-SCS Semiconductor Characterization System can simplify testing and analysis. The 4200-SCS is a measurement system that includes instruments for both I‑V and C‑V measurements, as well as software, graphics, and mathematical analysis capability. The software includes tests for making I‑V and C‑V measurements specifically on solar cells and deriving common PV cell parameters from the test data. This application note describes how to use the Model 4200-SCS to make
electrical measurements on PV Cells. Topics include the basic principles of PV cells, connections of the cell in the measurement circuits, forward and reverse I‑V measurements, C‑V measurements, measurement considerations, and sources of error. Basic Photovoltaic Cell Circuit and Device Parameters A photovoltaic cell may be represented by the equivalent circuit model shown in Figure 1. This model consists of current due to optical generation (IL), a diode that generates a current [Is(eqV/kT)], a series resistance (rs), and shunt resistance (rsh). The series resistance is due to the resistance of the metal contacts, ohmic losses in the front surface of the cell, impurity concentrations, and junction depth. The series resistance is an important parameter because it reduces both the short-circuit current and the maximum power output of the cell. Ideally, the series resistance should be 0Ω (rs = 0). The shunt resistance represents the loss due to surface leakage along the edge of the cell or due to crystal defects. Ideally, the shunt resistance should be infinite (rsh = ∞). If a load resistor (RL) is connected to an illuminated PV cell, then the total current becomes:
I = IS(eqV/kT – 1) – IL
PV Cell Photon hυ IL
Figure 1. Idealized equivalent circuit of a photovoltaic cell.
10 – Global Solar Technology – November/December 2009
Making I‑V and C‑V measurements on solar/photovoltaic
Cell Current (mA)
Maximum Power Area Pmax = ImaxVmax
Cell Voltage (V)
Vmax Voc Figure 3. Screen shot of PV cell project for the 4200.
Figure 2. Typical forward bias I‑V characteristics of a PV cell.
where: IS = current due to diode saturation IL = current due to optical generation
Imax = the current at the maximum power output Vmax = the voltage at the maximum power output Isc = the short-circuit current Voc = the open-circuit voltage
Several factors determine the efficiency of the solar cell, including the maximum power point (Pmax), the energy conversion efficiency (η), and the fill factor (FF). These points are illustrated in Figure 2, which shows a typical forward bias I‑V curve of an illuminated PV cell. The maximum power point (Pmax) is the product of the maximum cell current (Imax) and voltage (Vmax) where the power output of the cell is greatest. This point is located at the “knee” of the curve. The fill factor is a measure of how far the I‑V characteristics of an actual PV cell differ from those of an ideal cell. The fill factor is defined as: FF =
Another important parameter is the conversion efficiency (η), which is defined as the ratio of the maximum power output to the power input to the cell: η =
Pmax ______ Pin
where: Pmax = the maximum power output Pin = the power input to the cell defined as the total radiant energy incident on the surface of the cell
ImaxVmax ___________ IscVoc
These described parameters of the solar cell can be determined through electrical
characterization of the device. Using the 4200-SCS to make I‑V and C‑V measurements on the solar cell To simplify testing, a project has been created for the 4200-SCS that makes both I‑V and C‑V measurements on a solar cell and also extracts common measurement parameters such as maximum power, short-circuit current, open-circuit voltage, etc. The project is called “CVU_Pvcell” and is included with all 4200-SCS systems running KITE version 7.0 or later. A screen shot of the project is shown in Figure 3. This project has five tests, called ITMs (Interactive Test Modules), that perform a forward bias I‑V sweep (fwd-ivsweep), reverse bias I‑V sweep (rev-ivsweep), C‑V sweep (cvsweep), 1/C2 vs. V plot (C-2vsV) and C-f sweep (cfsweep). I‑V measurements using the 4200-SMU As described previously, many important
4200-SMU or 4210-SMU Source V–Measure I Mode Local
V-Meter Sense Output Adjust V-Source (feedback)
Figure 4. Connections of 4200-SCS’s SMU to solar cell.
Figure 5. Results of calculated parameters shown in sheet tab.
Global Solar Technology – November/December 2009 – 11
Making I‑V and C‑V measurements on solar/photovoltaic
Voltage (V) Figure 6. I‑V sweep of silicon PV cell generated with the 4200-SMU.
Figure 7. Slope method used to calculate the series resistance.
VReverse Bias Linear region used
∆VReverse Bias rsh ≈
to estimate rsh
∆VReverse Bias ∆IReverse Bias
log IReverse Bias
Figure 8. Typical reverse-bias characteristics of a PV cell.
device parameters can be determined from current-voltage (I‑V) measurements of the solar cell. The I‑V characteristics are measured using one of the Model 4200-SCS’s Source Measure Units (SMUs), which can source and measure both current and voltage. Two types of SMUs are available for the 4200-SCS: the Model 4200-SMU, which can source/sink up to 100mA, and the 4210-SMU, which can source/sink up to 1A. If the output current of the cell exceeds these current levels, then the output current may have to be reduced. One way of reducing the output is to reduce the area of the cell. If this is not possible, then the Keithley Series 2400 SourceMeter® instruments, which are capable of sourcing/sinking higher currents, may be used. Making connections to the PV Cell A solar cell connected to the 4200-SCS’s SMU for I‑V measurements is shown in Figure 4. A four-wire connection is made to eliminate the lead resistance that could otherwise affect the measurement accuracy. With the four-wire method, a voltage is sourced across the PV cell using one pair of leads (Force HI
and Force LO), and the voltage drop across the cell is measured across a Figure 9. Actual reverse bias measurement of silicon pv cell using 4200-SMU. second set of leads (Sense HI and Model 4200-SCS’s built-in mathematical Sense LO). The sense leads ensure that analysis tool, the Formulator. For the voltage developed across the cell convenience, the “CVU_Pvcell” project is the programmed output value and has the common parameters already compensates for the lead resistance. calculated and the values automatically appear in the Sheet tab every time the Forward Bias I‑V Measurements test is executed. Figure 5 shows some of Forward bias I‑V measurements of the the derived parameters in the Sheet tab. PV cell are generated under controlled These parameters include the short-circuit illumination. The SMU is set up to source current (ISC), the open circuit voltage (VOC), a voltage sweep and measure the resulting the maximum power point (Pmax), the current. This forward bias sweep can be maximum cell current (Imax), the maximum accomplished using the “fwd-ivsweep” cell voltage (Vmax), and the fill factor (FF). ITM. The user can adjust the sweep voltage Using the Formulator, the conversion to the desired values. As illustrated in efficiency (η) can also be calculated if the Figure 2, the voltage source is swept from power input to the cell is known. The V1 = 0 to V2 = VOC. When the voltage current density (J) can also be derived source is 0 (V1 = 0), the current is equal using the area of the cell. to the short-circuit current (ISC). When Figure 6 shows an actual I‑V sweep of the voltage source is an open circuit (V2 = an illuminated silicon PV cell generated VOC), then the current is equal to zero (I2 = by the 4200-SCS using the “fwd-ivsweep” 0). The parameters VOC and ISC can easily ITM. Because the system’s SMUs can be derived from the sweep data using the
12 – Global Solar Technology – November/December 2009
Making I‑V and C‑V measurements on solar/photovoltaic
sink current, the curve can pass through the fourth quadrant and allow power to be extracted from the device (I–, V+). Sometimes it may be desirable to plot log I vs. V. The Graph tab options support an easy transition between graphically displaying data on either a linear or a log scale. The series resistance, (rs), can be determined from the forward I‑V sweep at two or more light intensities. First, make I‑V curves at two different intensities. Knowing the magnitudes of the intensities is not important. Measure the slope of this curve from the far forward characteristics where the curve becomes linear. The inverse of this slope yields the series resistance: rs =
∆V ____ ∆I
Using additional light intensities, this technique can be extended using multiple points located near the knee of the curves. As illustrated in Figure 7, a line is generated from which the series resistance can be calculated from the slope. An important measurement feature of the system’s SMU as an ammeter is that it has very low voltage burden. The voltage burden is the voltage drop across the ammeter during the measurement. Most conventional digital multimeters (DMMs) will have a voltage burden of at least 200mV at full scale. Given that only millivolts may be sourced to the sample, this can cause large errors. The 4200-SCS’s SMU never produces more than a few hundred microvolts of voltage burden, or voltage drop, in the measurement circuit.
Reverse bias I‑V measurements The leakage current and shunt resistance (rsh) can be derived from the reverse bias I‑V data. Typically, the test is performed in the dark. The voltage is sourced from 0V to a voltage level where the device begins to break down. The resulting current is measured and plotted as a function of the voltage. Depending on the size of the cell, the leakage current can be as small as in the picoamp region. The Model 4200-SCS has a preamp option that allows making accurate measurements well below a picoamp. When making very sensitive low current measurements (nanoamps and smaller), use low noise cables and place the device in a shielded enclosure to shield the device electrostatically. This conductive shield is connected to the Force LO terminal of the 4200-SCS. The Force LO terminal connection can be made from the outside shell of the triax connectors, the black binding post on the ground unit (GNDU), or from the Force LO triax connector on the GNDU. One method for determining the shunt resistance of the PV cell is from the slope of the reverse bias I‑V curve, as shown in Figure 8. From the linear region of this curve, the shunt resistance can be calculated as:
∆VReverse Bias ______________ ∆IReverse Bias
An actual curve of a reverse-biased PV cell is shown in Figure 9. This curve was generated using the ITM “rev-ivsweep”. In this semi-log graph, the absolute value of the current is plotted as a function of the reverse bias voltage that is on an inverted x-axis.
In addition to determining the I‑V characteristics of a PV cell, capacitancevoltage measurements are also useful in deriving particular parameters about the device. Depending on the type of PV cell, the AC capacitance can be used to derive such parameters as doping concentration and the built-in voltage of the junction. A capacitance-frequency sweep can be used to provide information about the existence of traps in the depletion region. The Model 4200-CVU, the Model 4200-SCS’s optional Capacitance-Voltage Unit, can measure the capacitance as a function of an applied DC voltage (C‑V), a function of frequency (C-f), or a function of time (C-t). To make a C‑V measurement, a solar cell is connected to the 4200-CVU as shown in Figure 10. Like I‑V measurements made with the SMU, the C‑V measurement also involves a four-wire connection to compensate for lead resistance. The HPOT/HCUR terminals are connected to the anode and the LPOT/LCUR terminals are connected to the cathode. This connects the high DC voltage source terminal of the CVU to the anode. Not shown in the simplified diagram are the shields of the coax cables. The shields from the coax cables need to be connected together as close as possible to the solar cell. Connecting the shields together is necessary for obtaining the highest accuracy because it reduces the effects of the inductance in the measurement circuit. This is especially important for capacitance measurements made at the higher test frequencies. To reduce the effects of cable capacitance, it is also important to perform a SHORT cal, OPEN cal, and Cable Correction. These simple procedures are discussed in Section 15 of the 4200-SCS
4200-CVU AC Source
HCUR HPOT AC Voltmeter
Solar Cell LPOT
Figure 10. Connecting the 4200-CVU to a solar cell.
Figure 11. C‑V sweep of silicon solar cell.
Global Solar Technology – November/December 2009 – 13
Making I‑V and C‑V measurements on solar/photovoltaic
Figure 12. 1/C2 vs. voltage of a silicon solar cell.
Complete Reference Manual. Given that the capacitance of the cell is directly related to the area of the device, it may be necessary to reduce the area, if possible, to avoid capacitances that may be too high to measure. Also, setting the 4200-CVU to measure capacitance at a lower test frequency (10kHz) and/or lower AC drive voltage will allow making higher capacitance measurements. C-V sweep C‑V measurements can be made either forward-biased or reverse-biased. However, when the cell is forward-biased, the applied DC voltage must be limited; otherwise, the conductance may get too high. The maximum DC current cannot be greater than 10mA; otherwise, the DC voltage output will not be at the desired level. Figure 11 illustrates a C‑V curve of a silicon solar cell generated by the 4200-CVU using the “cvsweep” ITM. This test was performed in the dark while the cell was reverse-biased. Instead of plotting dC/dV, it is sometimes desirable to view the data as 1/C2 vs. V. The doping density (N) can be derived from the slope of this curve because N is related to the capacitance by:
2 N(a) = __________________ qESA2[d(1/C2)/dV] where: N(a) = the doping density (1/cm3) q = the electron charge (1.60219 × 10–19C) Es = semiconductor permittivity (1.034 × 10–12F/cm for silicon) A = area (cm2) C = measured capacitance (F) V = applied DC voltage (V)
Figure 13. C-f sweep of solar cell.
The built-in voltage of the cell junction can be derived from the intersection of the 1/ C2 curve and the horizontal axis. This plot should be a fairly straight line. An actual curve taken with the 4200-CVU is shown in Figure 12. This graph was generated using the “C-2vsV” ITM. The “Linear Line Fits” graph option can be used to derive both the doping density (N) and the builtin voltage on the x-axis. The doping density is calculated as a function of voltage in the Formulator and appears in the Sheet tab in the ITM. The user must input the Area of the device in the Constants area of the Formulator. C-f sweep The 4200-CVU can also measure capacitance as a function of frequency. The curve in Figure 13 was generated by using the “cfsweep” ITM. The user can adjust the range of sweep frequency as well as the bias voltage. Measuring the electrical characteristics of a solar cell is critical for determining the device’s output performance and efficiency. The Model 4200-SCS simplifies cell testing by automating the I‑V and C‑V measurements and provides graphics and analysis capability. In addition to the tests described here, the 4200-SCS can also be used to make resistivity measurements on the materials used for the PV cells, a process that is described in a separate Application Note, #2475, “Four-Probe Resistivity and Hall Voltage Measurements with the Model 4200-SCS,” which is available for download from www.keithley.com.
14 – Global Solar Technology – November/December 2009
Getting better all the time Title
Global Solar Technology â€“ November/December 2009 â€“ 15
Taiwan resumes growth in solar manufacturing
Taiwan resumes growth in solar manufacturing As I write this, companies are beginning to release their earnings reports. Third quarter results have been mixed with companies that serve the Chinese market (Chart 1) showing recovery and expansion while Japan, Europe and the U.S. remain cautiously optimistic. Government stimulus and incentive packages coupled with renewed credit availability have enabled utility companies to expand their solar power plant capacity while the housing hangover has smothered consumer spending. Recovery begins! A composite (Chart 2) of Taiwan solar/ photovoltaic companies (which report monthly) shows a strong recovery began in mid 2009 with the nation’s top three solar cell manufacturers (Chart 3), Motech, Gintech Energy and E-Ton Solar. All are running at full capacity and are expanding production capabilities.
• According to the Taipei Times and Digitimes, Motech (Chart 4), 20091009
a crystalline silicon (c-Si) solar cell manufacturer, expanded capacity to 600MWp and expects to be running at 100% capacity by year-end due to increased demand from Europe and the U.S. • Gintech Energy (Chart 5) stated that its inventory level decreased from an average of 90 days in 1H’09 to 20 days and it expects 3Q’09 solar cell shipments to reach 110 MW, more than the total for 1H’09. (Digitimes). • E-Ton (Chart 6) president Allen Guo was quoted in Digitimes as saying, “E-Ton reached full utilization of production capacity and international solar cell prices have rebounded significantly”. The company expects 30% of its 3Q’09 revenues to come from outsourcing to China-based solar cell makers who have exceeded their capacity or lack appropriate technology capabilities. • In addition, Neo Solar and SinoAmerican Silicon Products (SAS) also 20091013
Constant $ Growth Rates Converted @ Constant Exchange Rates
reported full capacity utilization and expansions. Neo Solar (Chart 7) which has more than 50% of the clients coming from Germany and Italy, is adding an additional 180MWp in capacity for a total of 400MWp by March 2010 (Digitimes). Silicon wafer supplier, Sino-American Silicon Products (Chart 8) stated that it has seen price recovery for its major products since the middle of June and it has restarted its Chunan, Taiwan plant expansion in order to increase its annual production capacity from 280 MW to 400MW (Digitimes). North American early reports look promising U.S.-based solar cell manufacturer SunPower posted a 3Q’09 record revenue of US $466 million and record production of 110 MW. CFO Dennis Arriola stated in its Q3 earnings report that “The company’s continued focus on working capital
Taiwan Solar/Photovoltaic Panel Companies Composite of 13 Manufacturers
2007/2006 Revenue Growth Up 68%
10 9 8 7 6 5 4 3
Henderson Ventures 10/2009 www.hendersonventures.com
16 – Global Solar Technology – November/December 2009
2 1 0
1 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9 00 01 02 03 04 05 06 07 08 09
CALENDAR YEAR Big Sun Energy Technology, e_TON Solar Tec, Gintech, Green Energy Technology (GET), Ligitek, Motech, Neo Solar Power, Phoenixtec Power Co (PPC), Precision Silicon, Sino-American Silicon Products (SAS), Sysgration, Tyntek, Wafer Works
Taiwan resumes growth in solar manufacturing
management is showing positive results as we successfully managed inventory levels and ended the quarter with a stronger balance sheet and more than $800 million in cash and investments, although the financing markets remain 20090102
challenging, we’re starting to see some improvement in the availability of financing for our projects.” • Canadian Solar raised its 4Q’09 and full year shipment guidance to 127 MW to 137 MW and 295 MW to 305
Top 20 Cell-companies Ranked by 2007 Production
Company Sharp Electronics Q-Cells Suntech Power Holdings First Solar SolarWorld Sanyo BP Solar Kyocera Motech Industries Solarfun Power Holdings SunPower Corp. Gintech Energy Corp E-TON SOLAR TECH Yingli Green Energy CEEG Nanjing PV Tech China Sunergy Co. Ltd Mitsubishi Ersol Solar Energy AG Jing Ao Solar Moser Baer Photovoltaic
Motech Monthly Revenues
Country Technology 2007 2008 2009 2010 Japan Crystalline 725 870 870 1250 Germany Crystalline 547 834 1055 1135 China Crystalline 320 590 590 590 USA Thin-film 317 484 1012 1012 Germany Crystalline 280 460 650 671 Japan Crystalline 270 365 365 665 UK Crystalline 257 480 600 800 Japan Crystalline 250 300 300 500 Taiwan Crystalline 240 330 500 660 China Crystalline 240 360 360 360 USA Crystalline 214 414 414 1000 Taiwan Crystalline 210 300 510 600 Taiwan Crystalline 200 320 400 500 China Crystalline 200 400 600 600 China Crystalline 200 390 550 600 China Crystalline 192 320 320 390 Japan Crystalline 190 280 310 430 Germany Crystalline 180 220 300 400 China Crystalline 175 175 175 175 India Crystalline 120 120 120 700 Total (in MW) 5327 8012 10001 13130 Total (Top 10) 3446 5073 6302 7743  also manufacturers thin-film, although crystalline is its primary technology
1 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9 00 01 02 03 04 05 06 07 08 09
Gintech Monthly Revenues
MW respectively. Its Chairman and CEO, Dr. Shawn Qu, said, “Demand has continued to be strong among our core customer group as well as among new customers. We anticipate that Q4 2009 will be even stronger than
e_TON Solar Tech Monthly Revenues
1 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9111 3 5 7 9 00 01 02 03 04 05 06 07 08 09
Neo Solar Power Monthly Revenues
Sino-American Silicon Products (SAS) Monthly Revenues
Global Solar Technology – November/December 2009 – 17
Taiwan resumes growth in solar manufacturing
• Q3 2009 in terms of shipments and we expect to maintain similar gross margins. We plan to increase our solar module manufacturing capacity to 1 GW, our solar cell capacity to 700 MW and our ingot and wafer capacity to 350 MW by the end of 2010 to meet demand levels.” Here are some clips from our Daily News service: Markets & business conditions “Average days of inventory for solar module/cell makers and polysilicon/wafer suppliers spiked 64.3% in 1Q09 to 121.9 days., spot prices for polysilicon, which were $180/kg at the beginning of 2009, are seen plunging -72% to $50 by year’s end.”—iSuppli China’s • cumulative installed base of 140MW of photovoltaics and is expected to reach 1.4GW to 2.6GW by 2012. —GTM Research • solar power sector produced more than 6,000 tons of polycrystalline silicon and 2 million kW of solar photovoltaic cells in 2008. German PV equipment industry orders declined 79% y/y in 2Q’09.—VDMA Japan’s solar cell shipments increased 82.5% y/y to 83.26 MW in April-June 2009.—Japan PV Energy Association Spain’s PV module installations are expected to reach 125MW in 2009, significantly below 500MW cap.—Spain’s Institute for Renewable Energy U.S. • imposed tariffs on imports of solar panels from China. • Senate passed H.R.3183, the Energy and Water Development and Related Agencies Appropriations Act. Materials & components 3M expanded Scotchshield solar film manufacturing in Singapore. AU Optronics increased stake in M.Setek to 15% with US$125M purchase of 244,073 common and preferred shares. Bridgestone • is investing 4.4 billion yen for a new factory in Seki, Gifu Prefecture, Japan, with a monthly solar cell film production target of 1,200 tons. • added new ethylene vinyl acetate production lines at its Seki Plant in Seki City, Japan, to expand its solar module adhesive film capacity. Cardinal Solar Technologies opened a 180,000 sq.ft. photovoltaic solar panel plant in Mazomanie, Wisconsin.
Centrosolar Glas increased its solar glass capacity to 6 million sq.m/yr. China Crystal Technologies (Oregon Crystal Technologies) is building its first U.S. solar component manufacturing plant in Gresham, Oregon. Dow Chemical • projects new solar shingles will generate US $5 billion in revenue by 2015 and US $10 billion by 2020. • began construction on its solar monosilanes facility in Thomas Twp., Michigan and completed a solar array and education center in Midland, Michigan. • sold Morton Salt and paid off a US $1 billion bridge loan incurred by Rohm & Hass acquisition. DuPont • and Applied Materials formed a collaboration for advancing multiple printing technology for increasing solar cell efficiency. • is investing USD 160 million to build a solar R&D center in Shatian, Hong Kong, and add workshops in Shenzhen. • expects its global thin-film solar panel sales to reach US $1 billion in 2012. Ferro began solar aluminum paste production in Suzhou, China. Giga Solar Materials debuted on Taiwan Emerging stock market. Konarka named Alex Valenzuela to VP of European business development and Alessandro Zedda to VP of materials development. Madico increased its Protekt photovoltaic backsheet technology manufacturing capacity from 4 GW to 7.5 GW. PPG issued 30 year warranty for DURANAR coatings used with photovoltaic systems. Rehm Thermal Systems introduced thermal oxidation process that eliminates residue contamination from photovoltaic metallization. Sixtron Advanced Materials appointed Praxair CTO Steven Lerner to the board. STR Holdings conducted first US solar IPO in 15 months. Tyco Electronics launched a micro website for the solar and photovoltaic industry. Voltaix® was ranked number 276 on Deloitte’s 2009 Technology Fast 500™ list. Process equipment 3S Industries & San-Du Solar Energy are jointly setting up a 100,000 sq ft module manufacturing facility in Malaysia. Abbeon Cal introduced the AETC-20 electronic thermocutter. Adept Technology named Rush laselle
18 – Global Solar Technology – November/December 2009
director of global sales & marketing. Applied Materials • named Mark Pinto to Sr. VP and GM of Energy and Environmental Solutions. • introduced its Baccini Esatto Technology multiple printing capability designed for increasing c-Si solar cell efficiency. • received 2009 Green Power Leadership award from U.S. Environmental Protection Agency. Cimetrix PV EIS group received 2009 SEMI Europe Standards Merit award. CVD Equipment appointed Kelly Walters to board of directors. Dyesol (50.1% holding) and Timo (49.9% holding) increased combined investment in Korea based JV Dyesol-Timo by 2 billion Korean won to finalize glass based product development. Dyesol appointed chairman of the board Richard Caldwell to executive chairman. EO Technics acquired Powerlaser’s laser business and assets. GT Solar opened its new 50,000 sq.ft. Asia Headquarters in Shanghai, China. Hon Hai’s Foxsemicon began shipping solar-energy equipment. Intermolecular introduced a solar cell testing system with the capability of testing 72 different cells on the same wafer at once. Komax relocated its Loganville plant to Springettsbury, Pennsylvania. Manufacturing Integration Technology of Singapore diversified into solar equipment industry. Manz Automation acquired Intech Machines. Nanometrics founder and vice-chairman of the board, Vincent Coates resigned from the board of directors. Newport released Oriel IQE-200, which permits simultaneous measurements of both EQE and IQE of solar cells, detectors or any photon-to-charge converting devices. Roth & Rau • India commenced operations in Mumbai. • appointed Rainer Erdmann to sales director for Europe and Asia. • opened a subsidiary and technology center in Neuchâtel, Switzerland. S.A.G. Solarstrom received ISO 9001:2008 Quality and Environmental Management and ISO 14001:2004 Quality Management certifications. Spire established wholly-owned subsidiary Spire Taiwan LLC. Westpak launched specialized testing services for the solar photovoltaic and solar thermal product markets.
Taiwan resumes growth in solar manufacturing
Silicon, ingots, wafers Semi-Materials succeeded in the production of polysilicon using selfdeveloped CVD reactor for monosilane. Comtec Solar is expanding its solar silicon production capacity to 504 MW by the end of June, 2010. Disco developed an inexpensive system that uses a diamond tip for precision processing of solar cells. Euro Multivision to enter polysilicon production to supply its planned 40 Mw photovoltaic solar cell manufacturing unit in Kutch, India. GCL • Solar leased 10,000 sq.ft, office space in Richland, Washington. • Poly subsidiary, Xiexin Development is investing $700 million to develop a 2gW silicon wafer project in Xuzhou, China. Green Energy added a second silicon ingot slicing plant. Haitai New Energy began building a 33.25 million/yr polysilicon wafer plant in Tangshan, China. LDK • President and COO Xingxue Tong assumed interim VP of manufacturing position after Nicola Sarno resigned. • began production at its 15,000 MT polysilicon plant in Xinyu, China. Leshan Ledian Tianwei Silicon Science and Technology began production with one furnace at its planned 3,000 MT polysilicon project. Lux added an ALD Vacuum Technologies SCU400plus DSS furnace for growing multicrystalline ingots Pozzolo Formigaro, Italy. MEMC • acquired SunEdison. • appointed Ken Hannah to Executive VP of MEMC and president of MEMC Solar Materials, Tim Oliver to Senior VP and CFO and Shaker Sadasivam to Executive VP of MEMC and of MEMC Semiconductor. • ceased production of silicon crystal ingots and wafers in Sherman, Texas and St. Peters, Missouri. Puhong New Energy (Zhejiang, China) produced a 400-kilogram polysilicon ingot. ReneSola acquired Dynamic Green Energy. Schmid installed equipment at its pilot polysilicon production plant in Saxony, Germany. Shin-Etsu is spending Y16bn t o double production capacity for silicon metal at its subsidiary in Australia. Sojitz plans to increase its annual volume of trade in high-purity metallic silicon by
150% to 50,000 tons within three to four years. Swagelok introduced photovoltaic cleanliness process specification (SC-06). Timminco restarted a third furnace and recalled staff at its Quebec silicon facility. Tokuyama to build a 65 billion yen polycrystalline silicon factory in the Samalaju Industrial Park in Sarawak, Malaysia. Wacker Chemie • and Dow Corning began building second phase of pyrogenic silica plant in Zhangjiagang, China. • backed out of JV with Schott Solar AG, exited solar wafer business. Yingli Green Energy entered cooperation with SiC Processing for exhausted cutting slurry recycling. Crystalline silicon cells, modules, panels Akeena Solar Andalay AC System was recognized as a 2009 breakthrough product by Popular Mechanics. Aleo Solar opened a sales office in Aix-enProvence, France. ARISE Technologies acquired Scheuten PV cell manufacturing plant in Gelsenkirchen, Germany. AU Optronics began production of crystalline silicon photovoltaic modules, with shipments estimated at 15-20MWp in 2009 and over 100MWp in 2010. AYT and Sitizn are jointly building a 300 million euro solar panel manufacturing plant in Turkey scheduled for completion in June 2010. Bakhu Holdings • appointed Xinan Zeng to CEO & CFO after founder Alexander Deshin resigned. • merged with Shenzen Xinhonglian Solar and moved to new facility in Shenzhen, China. BHEL • added an additional solar module manufacturing facility in Bangalore which increased annual capacity from 3 MW to 8 MW. • and BEL formed a JV to build a 250MW production facility for processing silicon wafers, solar cells and PV modules. Bosch Solar Energy (formerly ersol Solar) demonstrated a prototype of a monocrystalline metal wrap-through module. BP Solar, IMEC demonstrated 18% conversion efficiency using BP Solar’s Mono2 silicon. Centron Solar changed its name to Grape Solar.
China Nuvo Solar Energy acquired six provisional or utility patents from Photovoltaics, Inc. China Sunergy appointed Siegfried Yi Chou Hsu to CFO. Day4 Energy • extended its Day4® Electrode technology to back contact solar cells. • named James Topham CA to board of directors. Dow Chemical introduced a line of photovoltaic solar shingles that can be integrated into rooftops with standard asphalt shingle materials. Epco plans to enter the solar panel design and installation business in China as early as February 2010. ersol Solar Energy changed its name to Bosch Solar Energy. ET Solar Group named US Solar Distributing its premier module distributor in US. Fraunhofer Institute • opened a PV module innovation facility in Cambridge, Massachusetts. • added an Optomec aerosol jet solar lab system for front side metallization of solar cells. • achieved 23.4% efficiency with N-type solar cell. • Head of the Materials—Solar Cells and Technology department Dr. Andreas Bett received Becquerel Prize. G24i shipped world’s first commercial application of DSSC technology for mass consumer use. GreenSun developed colorful solar panels that don’t need direct sunlight. Heliatek developed organic solar cells with 6% confirmed efficiency that consist of “small molecules”—organic dyes synthesized from hydrocarbons. Hong Wei opened a 40MW module plant in Henan, China. IMEC large area solar cells with a shallow emitter and Cu-plated contacts reached 18.4% conversion efficiency. Innovalight achieved record 18% efficiency for its silicon ink solar cell. Intertek received CBTL accreditation for photovoltaic panels at its Lake Forest, California, facility. ITRI opened Taiwan PV testing labs. Jetion is investing RMB 2.5 billion to build a 10,000-sq.m. photovoltaic base in Lanzhou, China. LG Display is investing 50 billion won (US $40 million) to start commercial production of the solar power cells by 2012. Ligitek Photovoltaic • demonstrated first solar modules
Global Solar Technology – November/December 2009 – 19
Taiwan resumes growth in solar manufacturing
produced by auto-production lines in Taiwan. • moved to new plant in the Hsuling Tatung Technology Industrial Park. Mitsubishi Chemical developed solar cells for air conditioning in trucks. Moser Baer is investing Rs 2,000 crore to expand its Greater Noida and Chennai plants and develop two 5 MW gridconnected solar farms in Rajasthan and Punjab. Motech Solar installed and qualified an Applied Baccini back-end line for double printing applications at its volume production facility in Tainan, Taiwan. Novagen appointed Gary MacDonald to chairman of board. Oerlikon achieved stabilized record efficiency of more than 10% power conversion for amorphous silicon (a-Si) single-junction PV cells. Prism Solar Technologies replaced 50% of its solar module’s crystalline silicon with holographic planar concentrator film. Q-Cells • added Camstar’s SolarSuite for two new production lines in BitterfeldThalheim, Germany, and in its new 300MW+ factory in Malaysia. • achieved 15.9% module efficiency. • plans to roll-out polycrystalline cells with 17% conversion efficiency in 2010. RoseStreet Labs Energy demonstrated a nitride/silicon tandem solar cell. Samsung Electronics opened a 300 MW R&D and testing facility for solar cells in Giheung, Korea. Sanyo • achieved 22.8% conversion efficiency for its 98μm thick HIT solar cell. • is boosting its annual solar cell output capacity by 80% to 610,000kw by 2010, including addition of 180,000kw in Kaizuka and 90,000kw in Shimane Prefecture. SCHOTT Solar • closed its small sales and customer service office in Roseville, CA and added regional sales offices in San Jose, California, and Elmsford, New York. • increased its guarantee to 25 years for glass-foil solar modules and 30 years on double glass solar modules. Sharp • developed triple-junction compound solar cell with world’s highest conversion efficiency of 35.8%. • entered market for small photovoltaic components for mobile applications. • started operations at its new LCD panel and thin-film solar cell plant (Sharp Display Products Corporation) in Sakai City, Osaka Prefecture, Japan. Solarfun
• appointed Dr. Srinivasamohan Narayanan to VP of technology and John Breckenridge to board of directors. • subsidiary Jiangsu Linyang Solarfun began developing two solar projects with an aggregate capacity of 600MW. SolarTAC inaugurated world’s largest solar test and demonstration facilities in Aurora, Colorado. SolarWorld • opened a 210,000 sq.ft. module assembly plant in Hillsboro, Oregon. • is expanding module production at its plant in Freiberg, Saxony to 450 MW. • plans to build a 350 MW crystalline solar power module manufacturing facility in Hillsboro, Oregon by 2011. SunPower • President and CTO, Richard Swanson received Economist’s Innovation award for Energy and the Environment. • settled patent infringement lawsuit with SunLink . Suntech • expects 50 pct of panels to go to utility market by 2011. • achieved 16.53% multi-crystalline module conversion efficiency. systaic acquired SOLARWATT Cells.. Trina Solar is building 500 MW BIPV production base in China. TÜV Rheinland opened a solar test center in Cologne, Germany. Umoe Solar is setting up a solar panel component plant in Miramichi, Canada, and a solar research centre in Fredericton, Canada. Uni-CHEM leased space in Hudson, New Hampshire, from Spire to house automated 60 MW cell line and 50 MW module line. UNICOR—Federal Prison Industries added a 50 MW module manufacturing line in Sheridan, Oregon. Unitech Printed Circuit Board plans to expand its PV module capacity from 30 MWp to 50 MWp by June 2010. Wanxiang is building a 40,000-sq-ft solarpanel assembly plant in Rockford, Illinois. Westpak received ISO 17025:2005 solar testing accreditation. Worldwide Energy was ranked 226th fastest growing company in North America on Deloitte’s 2009 Technology Fast 500TM. Thin film Global CIGS thin-film solar-cell capacity is expected to reach 1,175MW by 2010.— DisplayBank Anwell Technologies began operation at its 40 MW a-Si thin-film solar panel plant in Henan, China. Ascent Solar
20 – Global Solar Technology – November/December 2009
• appointed Rafael Gutierrez to Sr, VP of sales and marketing. • raised $29.9 million in public offering of common stock. Best Solar two new assembly lines (totaling 130-MW) in Jiangxi Province to start production this year. Chi Mei Energy began shipping seethrough a-Si thin-film PV modules to the Middle East. DayStar Technologies • appointed CFO William Steckel to president and CEO and Howard Smith to VP of finance. • terminated EPOD merger plans. Evergreen Solar • Chairman, president and CEO Richard Feldt and CFO Michael ElHillow split SVP marketing and sales responsibilities after Dr. J. Terry Bailey left company. • appointed Henry Ng to GM—Asian operations. • and Jiawei Solar began construction on factories (with 100 MW capacity) in Wuhan, China, which are scheduled to be operational in Spring of 2010. First Solar • named Robert Gillette to CEO. • was added to the S&P 500 Index. Flisom is setting up a 5 MW pilot plant in Duebendorf, Switzerland, for commercializing flexible and lightweight thin-film photovoltaic solar modules. GE plans to switch to CdTe thin film solar production within the next two years. GroupSat added RENA inline cleaning and inline CdS deposition systems for its new CIGS thin film solar cell production line in Mudu, Suzhou China. Heliatek organic solar cells reached 6 % confirmed efficiency. KSK Surya Photovoltaic Venture purchased two Applied SunFab™ thin film production lines for its new 150 MW facility in Hyderabad, India. Nanosolar • achieved 16.4% efficiency for its CIGS thin-film solar cells. • completed a 640 MW panel-assembly factory in Luckenwalde, Germany and began serial roll-to-roll production of its flexible CIGS cells at its San Jose, California, facility. NexPower (UMC affiliate) • is constructing a third thin-film solar cell production plant (with 125 MW/ yr capacity) in Central Taiwan Science Park. • is investing NT $90 billion to build seven thin-film solar cell production plants in Houli Science Park over the next five years. Odersun • appointed Uwe Hering to chief sales
Taiwan resumes growth in solar manufacturing
and marketing officer. • was named to The “Global Cleantech 100” as one of the 100 most promising cleantech companies worldwide. Sharp to start thin-film production solar cell production March 2010 at its new LCD panel and solar cell manufacturing plant in Sakai City, Japan. Showa Shell to spend US $1.1 bln to convert former Hitachi Plasma Display plant in in Miyazaki Prefecture, Japan into 900 MW/yr thin-film solar plant by 2H’11. Signet Solar (Mochau, Germany) added a BrightView Systems integrated metrology system. Solarion • achieved 13.4% for CIGS on a plastic substrate produced on an industrial roll-to-roll system. • to add 10 MW/yr thin-film panel commercial production line in Leipzig, Germany, in 2010. Solarmer Energy achieved 7.6% efficiency with a plastic solar cell. SoloPower appointed Arthur Rudin to VP of product development and sales Robert Muhn to GM of sales. Solyndra, is building a second solar panel manufacturing plant (with 500 MW/yr capacity) in Fremont, California. Sunovia and EPIR achieved increase of
over 45% in open circuit voltage for CdTe thin film solar cells. TGI Solar Group appointed John Litvinchuk as board member and COO. Thin Film Research Lab (GCM) launched a new website www.gcmlab.ca. Thin Film Solar Technologies is constructing a thin film PV panel factory in Paarl, South Africa, which is scheduled to operational December 2010. TSMC began manufacturing CIGS thinfilm PV modules. XsunX • entered joint business agreement with Intevac to collaborate on processes and equipment for manufacturing CIGS thin-film solar cells. • dropped $50M plan to build 90,000sq.ft., 25 MW thin-film solar module plant in Wood Village, Oregon.
cluster-type PVD sputtering equipment used to make CIGS thin-film photovoltaic modules. M+W Zander completed 90 MW thinfilm plant in Saxony-Anhalt, Germany for Q-Cells subsidiary, Solibro. Mustang Vacuum Systems moved from Sarasota County to 50,000-sq.ft. facility in Manatee County. RBI Holdings Limited acquired Apollo Precision; changed name to Apollo Solar Energy Technology. Solar Metrology introduced in-situ XRF tool for CIGS composition and thickness measurement. Solar Thin Films completed reverse stock split and changed trading symbol to SLTZ:OB. Trident Solar launched 256Jet-S™ inkjet printhead for solar PV production.
Thin film process equipment and materials Global thin film silicon photovoltaic cell production equipment market to increase by 6.7 times the 2008 level in 2015.—Fuji Keizai A-Power acquired Evatech for US $49.9 mln in bid to expand presence into thinfilm solar technology. FSE Corporation began production of
Jon Custer-Topai is vice president of Custer Consulting Group and responsible for the corporation’s market research and news analysis activities. Jon is a member of the IPC and active in the Technology Marketing Research Council. jon@ custerconsulting.com
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Global Solar Technology – November/December 2009 – 21
Interview Getting better all the time
Interview—Brice Le Gouic, Yole Développement The rapid growth of solar PV power industry has created a multi-billion market for manufacturers of inverters, which convert solar power to grid power. A new report from Yole Développement (Lyon, France) tracks the current trends, manufacturers’ strategies, the shape of the market today and tomorrow. Journalist Valérie Thompson gets the highlights from Yole’s Brice Le Gouic. Your area of specialization is power electronics and compound semiconductors, why focus on solar PV inverter trends this time around? The PV inverter market generated about €2.5 billion in sales in 2008. It is set to more than double over the next five years, growing to €5.91 billion in 2014. It is a significantly sized market, an opportunity worth noting by electronics industry giants as well as new entrants. The PV inverter market has its own unique shape in terms of segments and trends. The supply chains are evolving, and there are some technological changes afoot that are worth paying attention to, such as the use of new materials for semiconductor devices (SiC, GaN), and the emergence of disruptive technologies like microinverters. We also take a close look at the actual manufacturers, their market share and their efforts to increase efficiency, reduce cost, and boost reliability, with consideration of what is driving this trend.
On what did you base your market forecasts for the next five years? The data used includes incentives and financing conditions in 50 countries, along with the targets for solar energy, and government policy. At the same time, we considered the installed base, segmentation, and current market
penetration. This gave us the data to work up the size of the inverter market segment by segment. We made the forecasts taking into account the 2009 crisis and impact on PV industry.
comes to industrial scale power conversion units. It is focusing on the solar farm segment for the moment. And Siemens is already one of the top 10 suppliers with close to 2% market share.
Who are the key players on the supply side?
Let’s go a bit deeper on the key trends you mentioned. What are your observations?
There are more than 40 suppliers nowadays, most of them established and specialized in solar inverters. Despite that, the market leader, Germany’s SMA, is seeing its revenues grow while its market share is decreasing. SMA remains the market leader with 34% of the market, Fronius is next with 10.1% closely followed by Kaco with about 9.9%.
The size of the market sounds big enough to attract attention of major power conversion systems manufacturers—and yet it remains the territory of solar-specialized manufacturers, like Germany’s SMA and Austria’s Fronius. Actually, there is a growing number of new entrants, many of them are power conversion system vendors—with large-sized inverters as their core activity—that are moving in now that solar plant sizes are increasing from 200 kw to megawatt sizes. We are seeing the entry of large companies like ABB, which is a global player when it
22 – Global Solar Technology – November/December 2009
Inverters are getting bigger. A centralized architecture is another key trend. Bucking the trend is the emergence of so-called micro inverters. Clearly, system sizes depend on the application and where it is located. In cities, the presence of sources of shadow, distance between buildings, available area and size of the installation, like BIPV in countries like Japan, put demands on the inverter design. It is one of the objectives of this report is to see how the various market segments impact PV inverter systems designs and on the players’ strategy.
Take a step back for me and describe how you have segmented the market. Three market segments residential, commercial rooftop (industrial rooftop, BIPV/walls and sometimes in playgrounds), and solar farms. The residential market is currently a high margin business, but eventually the margins will shrink. It will be become
high-volume, low-cost, low margins. The solar farm segment is characterized as low volume, high cost/high margin. The industrial segment is a mix of both of these.
as well as requiring a fitting strategy for established players.
What is a key trend for each segment?
It is fair to say that PV inverter makers have understood that their product is the central point of a PV plant. Five years ago, each player was working individually on their product, developing it, without paying a lot of attention to the overall supply chain. Now partnerships with systems integrators and with PV module manufacturers are becoming more common. More and more, complementary solution development is a trend. We are seeing supplier vertical integration become more evident. In the past, suppliers tended to be focused on a single market segment, but there is a trend towards addressing two or more segments now. For example, Kaco is a well-established smaller inverter-maker that is increasingly adding larger systems to its product line. Concurrently, we see companies like SMA growing their portfolio to include power-monitoring systems.
Residential systems are increasingly being sold as all-in-one kits, and the seller is the system integrator. For the commercial/ industrial market segment, we note that in system sizes of 10 to 100 kW customization is more common. While there is a higher variety of architectures, it is tending generally towards centralization. The largest size installation, solar farms, has been driving the centralization trend. Commercial systems of 100 to 500 kW are also tending towards a centralized architecture, as much as possible. It is a “solar farms” approach.
You mentioned that the emergence of larger solar farms is a trend in the PV industry, what impact does that have on inverters? Financial support from governments and banks favor bigger installations. That goes for solar farms and industrial buildings, but also standard residential. France recently increased the size of the residential rooftop system, for example. This implies a serious increase of inverter size in general,
Amongst established inverter suppliers, what strategic business trends do you see?
Can you elaborate on your comment that PV inverter-makers understand their central role in the development
of new PV plants and systems? It is evident in their efforts to increase size of inverters in sync with the market trends, but it is also evident in their efforts to reduce cost, increase efficiency and reliability. Take cost for example. Until the recent drop in polysilicon price, the inverter did not have a significant effect on the global cost of an installation. This is not the case anymore. Module costs are decreasing at a faster rate than inverters. Inverter manufacturers will have to cut their production cost. They can reduce material costs or labor (comprising production and testing). Since labor is only a small portion, efficiency gains become much more critical. Yole Développement has released a market & technology study, PV Inverter Trends, that examines current PV inverter solutions, technical challenges and future trends. For more information on this market & technological analysis, contact David Jourdan (jourdan@ yole.fr). Brice Le Gouic is market analyst at Yole Développement working in the areas of market and technology analysis in the fields of power electronics and related applicative markets. Thank you, Valérie and Brice.
Global Solar Technology – November/December 2009 – 23
Technological developments Solar simulators—beyond Class A
Technological developments Lower-cost solar cells to be printed like newspaper, painted on rooftops Solar cells could soon be produced more cheaply using nanoparticle “inks” that allow them to be printed like newspaper or painted onto the sides of buildings or rooftops to absorb electricity-producing sunlight.
Brian Korgel, a University of Texas at Austin chemical engineer, is hoping to cut costs to one-tenth of their current price by replacing the standard manufacturing process for solar cells—gas-phase deposition in a vacuum chamber, which requires high temperatures and is relatively expensive. “That’s essentially what’s needed to make solar-cell technology and photovoltaics widely adopted,” Korgel said. “The sun provides a nearly unlimited energy resource, but existing solar energy harvesting technologies are prohibitively expensive and cannot compete with fossil fuels.” For the past two years,
Korgel and his team have been working on this lowcost, nanomaterials solution to photovoltaics – or solar cell – manufacturing. Korgel is collaborating with professors Al Bard and Paul Barbara, both of the Department of Chemistry and Biochemistry, and Professor Ananth Dodabalapur of the Electrical and Computer Engineering Department. They recently showed proof-ofconcept in an issue of Journal of the American Chemical Society. The inks could be printed on a roll-to-roll printing process on a plastic substrate or stainless steel. And the prospect of being able to paint the “inks” onto a rooftop or building is not far-fetched. “You’d have to paint the light-absorbing material and a few other layers as well,” Korgel said. “This is one step in the direction towards paintable solar cells.” Korgel uses the lightabsorbing nanomaterials, which are 10,000 times thinner than a strand of hair, because their microscopic size allows for new physical properties that can help enable higher-
Suntech achieves world record conversion efficiency for a multicrystalline module Suntech Power Holdings Co., Ltd., achieved a new world record conversion efficiency of 15.6% on a commercial grade multi-crystalline silicon PV module. This conversion efficiency surpasses the previous record of 15.5% (aperture area only) set by Sandia National Labs 15 years ago. The multi-crystalline module conversion efficiency was independently
Chemical engineering Professor Brian Korgel tests one of his printed solar cells.
efficiency devices. In 2002, he co-founded a company called Innovalight, based in California, which is producing inks using silicon as the basis. This time, Korgel and his team are using copper indium gallium selenide or CIGS, which is both cheaper and benign in terms of environmental impact. “CIGS has some potential advantages over silicon,” Korgel said. “It’s a direct band gap semiconductor, which means that you need much less material to make a solar cell, and that’s one of the biggest potential advantages.” His team has developed
tested by Fraunhofer Institute for Solar Energy Systems ISE in Germany. Suntech’s world record breaking multicrystalline silicon module is powered by Pluto PV cells utilizing solar grade silicon with each PV cell having a conversion efficiency well over 17%. The previous record was based on an aperture area or frameless module. In contrast, Suntech’s new world record efficiency includes the framed area, without which Suntech believes it would achieve a conversion
24 – Global Solar Technology – November/December 2009
solar-cell prototypes with efficiencies at one percent; however, they need to be about 10 percent. “If we get to 10 percent, then there’s real potential for commercialization,” Korgel said. “If it works, I think you could see it being used in three to five years.” He also said that the inks, which are semi-transparent, could help realize the prospect of having windows that double as solar cells. Korgel said his work has attracted the interest of industrial partners.
efficiency of well over 16%. The world record conversion efficiency was accepted by the scientific journal Progress in Photovoltaics (PIP), which offers a prestigious forum for reporting advances in the PV industry. Professor Martin Green, research director of the ARC Photovoltaics Centre of Excellence at the University of New South Wales, Australia, and member of the PIP committee, said, “Improving the conversion efficiency of multi-crystalline
silicon modules has proven particularly challenging and this is a very impressive achievement for such a large module from a commercial supplier. I can confirm that the 15.6% multi-crystalline module result is the highest known conversion efficiency measured by a PIP-recognized test center.” “This is a tremendous result for Suntech,” said Dr. Stuart Wenham, Suntech’s chief technology officer, “and clearly demonstrates the power and versatility of the Pluto technology, which can be applied to both mono and multi-crystalline wafers. The fact that this module was produced on our commercial scale production lines using regular solar grade silicon is of particular note. The best news is that we believe there is still room for plenty more improvement in Pluto as we push the boundaries of technology development to bring more powerful and reliable solar products to market.” Suntech has initiated commercial shipments of Pluto powered modules and currently expects to ship 10MW to 15MW of Pluto products in 2009. www.suntechpower.com Flexible CdTe on polymer film achieves a new record efficiency of 12.4% Researchers from EMPA (Swiss Federal Laboratories for Materials Testing and Research) Dubendorf, near Zurich have improved the efficiency of flexible CdTe thin film solar cells to 12.4% value. The laboratory for Thin Films and Photovoltaics (www.empa.ch/tfpv) of EMPA, Switzerland, has developed highest efficiency flexible CdTe thin film solar cells on a lightweight polymer (polyimide) film by using a low temperature (below 450°C) vacuum evaporation process to grow CdS/CdTe layers and a subsequent annealing step in air. Another highlight of this 12.4% device structure is the use of ZnO:Al as a transparent electrical contact instead of the expensive ITO (indium tin oxide) layer they used earlier in 11.4% efficiency solar cells. Substitution of ITO with a bi-layer of ZnO/ZnO:Al also improved process yield and reproducibility of high efficiency solar cells. The photovoltaic parameters of the 12.4% efficiency solar cell measured under standard AM1.5 illumination condition are Voc= 823 mV, Jsc= 19.6 mA.cm-2, FF= 76.5%. The research group, under the leadership of Prof. Dr. Ayodhya Tiwari, has been involved in the development of CdTe solar cells on glass and polymer substrates for several years. Development of low
temperature and compatible processes were the main challenge in addition to the reduction of optical and electronic losses limiting the cell performance. All the process steps of the flexible solar cells are compatible with continuous in-line processing and can be transferred to rollto-roll manufacturing of large area solar modules with high deposition speed. Such high efficiency flexible CdTe solar cells could become a low cost option for cost effective solar electricity generation in near future. Suniva ARTisun™ solar cells surpass 18% efficiency in production Suniva, Inc.’sARTisun™ series solar cells are achieving conversion efficiencies of more than 18% in production, a record for screen-printed cells in regular full-scale production. “Customers are expecting highquality, high-efficiency products at lower costs,” said John Baumstark, CEO. “Suniva continues to lead these market requirements, delivering cells, and modules from our partners, that strike a sensible balance of power and affordability.” Suniva’s ARTisun series solar cells are manufactured with optimized metallization techniques and proprietary process innovations, both of which maintain low cost while extracting the highest efficiencies possible. Suniva produces solar cells which are integrated into high-performance solar modules available through Suniva and its global customer partners. UNSW achieves new solar power world record UNSW solar cell researchers have set a new world record of 43% of sunlight converted into electricity. The UNSW team, led by Scientia Professor Martin Green, research director of the UNSW ARC Photovoltaics Centre of Excellence, combined with two US groups to demonstrate a multicell combination that has set the new benchmark for converting sunlight into electricity by any possible approach. “Because sunlight is made up of many colours of different energy, ranging from the high energy ultraviolet to the low energy infrared, a combination of solar cells of different materials can convert sunlight more efficiently than any single cell,” Professor Green said. Professor Green, with colleague Dr Anita Ho-Baillie, led the team that developed a silicon cell optimised to capture light at the red and near-infrared
end of the spectrum. That cell was able to convert up to 46 per cent of light into electricity. When combined with four other cells, each optimised for different parts of the solar spectrum, the five-cell combination converted 43 per cent of the sunlight into electricity, bettering the previous world record by 0.3 per cent. “Our group’s silicon cell was the key contributor to the new result,” said Professor Green. Professor Stuart Wenham, director of the ARC Centre, said the new record was not directly comparable to the 25 per cent efficiency world record for an individual solar cell set by UNSW last year. However, it was an important pointer for the future potential of solar photovoltaic power. “This latest record involves an expensive combination of cells and the sunlight was focused to produce a much higher intensity than standard sunlight for these measurements. It does show, however, what eventually may be practical,” said Professor Wenham. Ben-Gurion University of the Negev develops thin films showing promise for solar applications Researchers at Ben-Gurion University of the Negev have developed thin films that exhibit carrier multiplication (CM). This development is of great interest for future solar cells. The films were synthesized at BGU by Prof. Yuval Golan and PhD student Anna Osherov of the Department of Materials Engineering and the Ilse Katz Institute for Nanoscale Science and Technology. The letter was published this week in Nature Physics. One of the important factors limiting solar-cell efficiency is that incident photons generate only one electron–hole pair, irrespective of the photon energy. Any excess photon energy is lost as heat. Carrier Multiplication (CM) has been thought to be enhanced significantly in nanocrystalline materials such as quantum dots, owing to their discrete energy levels and enhanced Coulomb interactions. The BGU team demonstrated that contrary to this expectation, for a given photon energy, carrier multiplication occurs more efficiently in bulk PbS and PbSe films than in nanocrystalline films of the same materials. “Films developed at BGU show CM, in which each incoming photon (tiny quantity of sunlight) creates more than one electron-hole pair,” Golan explains. “This can potentially be used for making more efficient solar cells. The
Global Solar Technology – November/December 2009 – 25
new physics behind this work are that while CM has been mostly demonstrated in nanocrystalline materials (“quantum dots”), we now show that CM can be obtained also in single crystal (‘bulk’) films of lead sulfide and lead selenide.” Notably, the films were prepared using chemical solution deposition, an attractive, inexpensive deposition technique for which the Golan group at BGU has received considerable recognition. The research was carried out as part of an international collaboration with counterparts in France and the Netherlands. Innovalight achieves record efficiency silicon-ink solar cell Innovalight, Inc., a privately-held firm providing printed silicon ink solar cell technology, has demonstrated a record 18% conversion efficiency with siliconink processed solar cells. The industry standard size solar cell results were independently certified by two of the world’s recognized solar cell testing centers, the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL) and The Fraunhofer Institute for Solar Energy Systems (ISE) in Germany. Innovalight’s proprietary silicon ink and processing technologies allow crystalline silicon solar cell manufacturers to dramatically boost output capacity, solar cell performance as well as reduce costs with a simplified additional step to already installed manufacturing lines. Crystalline silicon solar cell technology accounts for 86% of the commercial solar panel market today, according to Paula Mints, principal analyst for Navigant Consulting, Inc., a solar industry research firm. “Recently, NREL verified 18% efficiency which is a very significant achievement,” said Martha Symko-Davies, senior program manager at NREL. “We also are pleased that Innovalight has recently been awarded a $3 million Technology Incubator subcontract through the National Renewable Energy Laboratory, funded under the Department of Energy.” Innovalight is currently working with a number of solar cell manufacturing companies and is ramping production of silicon ink at its site in Sunnyvale, California. The company is developing technologies based on silicon ink to ultimately bring conversion efficiencies of crystalline silicon solar cells to over 20% RSLE scientists discover carbonfree hydrogen fuel source utilizing
thin film solar cell RoseStreet Labs Energy (RSLE) scientists announced a leap forward in generating hydrogen gas directly from sunlight by a photoelectrochemical cell (PEC). This hydrogen fuel is generated spontaneously in a single device without external power and without petroleum products such as natural gas. Hydrogen gas is a key resource for next generation hydrogen fueled cars, and also a key component in the renewable process of harvesting biofuels and biodiesel for replacement of oil based gasolines and jet fuels. RSLE’s discovery is coupled with RSLE’s Full Spectrum photovoltaic development which is expected to start field trials in late 2010 with +25% efficiencies. Full Spectrum technology is primarily based on nitride thin film semiconductors, which have excellent robustness to extreme environments including solar radiation, heat and corrosive environments. RSLE’s photoelectrochemical cell development is targeting the high performance terrestrial market for renewable energy. Bob Forcier, CEO of RSLE, stated, “We are excited about this new development in capturing the full spectrum of the sun for not only instantaneous power generation, but also for energy storage via liquefied hydrogen or to assist the emerging biofuel and biodiesel efforts. Although this is a significant milestone in our scientific research in Nitride Thin Film photovoltaics, it also represents the opportunity to commercialize this technology to the next level with RoseStreet’s partners.” Global Solar Energy’s CIGS production material achieves 15.45% efficiency Global Solar Energy, Inc., announced that the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL), the nation’s primary laboratory for renewable energy and energy efficiency research and development, confirmed 15.45% total area efficiency for Global Solar’s production level CIGS material. Adding to this news, Global Solar announces a peak efficiency of 11.7% for production CIGS solar cell strings manufactured at its 35-megawatt German and 40-megawatt U.S. plants. With these benchmarks, Global Solar continues to advance the thin film photovoltaic market and underscores its leadership as the only manufacturer of CIGS cells on a flexible substrate in full scale production.
26 – Global Solar Technology – November/December 2009
“The 15.45% total-area conversion efficiency, independently verified by NREL for a thin film CIGS solar cell fabricated by Global Solar Energy, is a significant achievement for such rapid deposition on a metal foil substrate in a manufacturing environment,” says Dr. Harin S. Ullal, National Center for Photovoltaics, National Renewable Energy Laboratory in Golden, CO. This research was supported in part by the Thin Film PV Partnership Program at NREL. Global Solar Energy has been in production of its CIGS thin film solar cells on flexible materials for more than five years, bringing the low cost, high efficiency and high-performance of CIGS technology to a variety of applications. RoseStreet Labs Energy demonstrates world’s first tandem nitride/silicon solar cell RoseStreet Labs Energy, Inc. announced a breakthrough demonstration of the first known nitride/silicon tandem solar cell. Utilizing the same nitride material technology as solid state lighting and blue lasers, RSLE fabricated and tested a working photovoltaic cell that couples a silicon solar cell with a nitride thin film. This is a major milestone in RSLE’s product roadmap to achieve substantially higher solar efficiencies than standard silicon or other thin film solar cells. This hybrid device is expected to achieve practical efficiencies of 25-30%, and RSLE is planning on production of this technology starting the Q4 of 2010. RSLE’s discovery is on RSLE’s Full Spectrum photovoltaic product roadmap. Full Spectrum technology is primarily based on nitride thin film semiconductors, which have excellent robustness to extreme environments including particle radiation, heat and corrosive environments. “We are quite excited about this new hybrid solar cell that marries low cost nitride thin film with the massive infrastructure of silicon solar cells,” said Bob Forcier, CEO. “Our target market for this hybrid device is the high performance sector for photovoltaics which we estimate to be over 1% of the $34B solar cell global market. SANYO develops ultra-thin HIT solar cell with the world’s highest-level conversion efficiency SANYO Electric Co., Ltd. Has realized a 22.8% cell energy conversion efficiency, for a research-level HIT solar cell. This comes close to the world’s best conversion efficiency of 23.0% in a practical size
(100 cm2 or more) announced in May 2009. SANYO’s solar cell improvement was realized using a cell thickness of 98μm, which is less than half the previous thickness. Background: With crystalline silicontype photovoltaic cells such as HIT solar cells, the most important issue for reducing the cost of photovoltaic systems is the achievement of both energy conversion efficiency and a thin silicon wafer, which is the energy generation layer. Generally, reducing the thickness of the silicon wafer in order to save resources and reduce costs results in less optical absorption and causes energy conversion efficiency to drop. Now SANYO has developed technology that can greatly control the drop in performance, which has been the issue for making even thinner cells. SANYO did this by using its technology for high efficiency creation developed over many years for its HIT solar cells, which feature high energy conversion efficiency. As a result, SANYO has achieved the world’s highest-level conversion efficiency of 22.8% at the research level in a practical size, using an ultra-thin HIT solar cell with a thickness of 98μm, which is less than
half the thickness of a conventional highefficiency solar cell. In the future, SANYO will focus on advancing applications for mass-production products with technology that offers both high conversion efficiency and a thinner cell for the newly improved HIT solar cell. Sunovia Researchers shatter world record open circuit voltage (Voc) for CdTe thin film solar cells Sunovia Energy Technologies, Inc. and partner EPIR Technologies, Inc. have fabricated single-junction and two-junction cadmium telluride (CdTe) based solar cells that have far surpassed the long-standing world record open circuit voltage (Voc) for thin film CdTe solar cells. The partners’ single-junction and twojunction devices exceeded the highest Voc values ever reported publicly by research institutions on thin film CdTe solar cells (including NREL and others) by over 45%. They called the Voc breakthroughs significant because the amount of electric power generated by a solar cell is directly proportional to its open circuit voltage. So doubling the Voc of a solar cell results in a doubling of power output, if all other
characteristics remain the same. The results reported by the partners will enable the companies to create solar cells with much higher efficiencies than other CdTe-based solar cell technologies. Open circuit voltage has traditionally been the most difficult performance metric to optimize in CdTe solar cells and the Partners’ CdTe-based (also known as II-VI materials) solar cells achieved open circuit voltages of 1.34 V and 1.75 V in the singlejunction and two-junction configurations, respectively. The 1.34 V value in the single-junction configuration is more than 95% of the theoretical upper limit for the II-VI alloy used by the partners. In contrast, the highest reported Voc for a CdTe solar cell is 0.91 V, representing about 76% of the theoretical maximum for CdTe. By fabricating II-VI solar cells with open circuit voltages close to the theoretical upper limit for the materials utilized, the partners have developed next-generation, high efficiency CdTe-based solar cells, which will accelerate the push of clean solar-generated electricity towards grid parity. The partners recently announced the expansion of their pilot production facilities, and are working to complete the initial 100 MW of manufacturing capacity. Their proprietary cell manufacturing process requires substantially less space than competing solar technologies, and is scalable at a fraction of the previous cost. The utilization of a silicon (Si) substrate greatly lowers manufacturing costs and allows the Partners to employ proven manufacturing techniques and equipment developed over more than 40 years during the evolution of the micro-chip industry. According to Dr. Michael Carmody, senior director for development of photovoltaic materials at EPIR Technologies, “These are by far the highest Voc measurements ever exhibited by a CdTe-based solar cell. There is no data in the literature that comes close to what we have achieved, and we believe that our two-junction device also represents the first ever high efficiency monolithic, two-junction solar cell using CdTe or any other II-VI material. The company’s two-junction II-VI on Silicon design will reach production efficiencies over 35% and will cost only a small fraction of the cost of three-junction III-V solar cells. Three-junction II-VI on Silicon cells will have even higher production efficiencies without much added cost.”
Global Solar Technology – November/December 2009 – 27
Show review: 24th European Photovoltaic Solar Energy Conference & Exhibition
The dream lives on, but business slow at the 24th EUPVSEC
25th EU PVSEC
September 6-10, 2010 Feria Valencia, Valencia, Spain www.photovoltaic-conference.com
EUPVSEC lived up to expectations as the leading global solar event. Scientists, engineers, manufacturers, installers, bankers and investors all made their way to Hamburg, in northern Germany, for the four-day event in late September. Printing technologies seemed to dominate the new equipment offerings, with new platforms from Asys, Baccini and DEK, while the industry was buzzing about the new acquisition of NRT Technologies by Indium Corporation, announced on the first day of the show. The conference was well-attended, and the policy debate raged on with government representatives from the EU Commission, Germany and the US deliberating the strengths and weaknesses of FITs , building regulation reform and other incentives to stimulate the PV industry. On the show floor, there were many business announcements and new innovations. Here is just a snapshot:
DEK Solar demonstrated their ongoing commitment to the PV industry with the introduction of the PV3000 printer. This is a major step forward from its predecessor and boasts three print heads running in parallel at a capacity of 1,200 wph each, enabling continuous production in the event that one print head stops for maintenance. At
the front of the system are three loaders that feed the wafers onto the entry conveyor. The walking beam system then indexes the wafers onto the print platform. After printing, it indexes them onto the exit conveyor, where they pass through a post-print inspection system before being aligned for the three-lane dryer, developed by Heller, or rejected as defective. The dryer itself is only two metres in length, uses low energy and contains a catalyst to breakdown the solvents released in the process. The dryer uses a thermal air system to recirculate the energy within chamber. The PV3000 is capable of print on print, selective emitter and selective etching. The entire unit, including the dryer, claims the smallest footprint in the industry: less than 17 metres. (video) Cookson added the Alpha PV Ready Ribbon to its growing family of PV products. Cookson call the Ready Ribbon “a minor disruptive technology for tabbing and stringing.” I am sure that operators using this new product would agree.The Ready Ribbon is a pre-fluxed ribbon that provides improved throughput, uses less flux and gives increased peel strength. The key advantage to a tabbing and stringing line is that you no longer have to spend an hour cleaning off the sticky flux residues at the end of each
28 – Global Solar Technology – November/December 2009
shift. (video) Oerlikon are predicting strong growth of their turnkey systems from 46 MW today to 500 MW by 2013. The Swiss-based manufacturer also announced the largest installation in the company’s history, a 70 MW installation at Tianwei Solar Films in Taiwan, who will supply Thailand Green Energy Co. Almost simultaneously, Oerlikon released news about an increase in stabilized efficiency to 10% of its amorphous silicon technology (a-Si) single junction cells utilizing their proprietary micromorph® PV technology, confirmed by NREL. Atlumin was formed only in January 2009 with seed capital from parent group MCP Group, the global mining conglomerate. Already they are the largest providers of CdTe in the world and count First Solar among their many clients. Atlumin also offer the full range of CIGS metals: copper, indium, gallium and diselenide. The materials can be supplied as chemicals or compounds, fabricated into wire, ribbons or performs, and supplied as rotary and planar targets. Rounding out the company’s services, Atlumin offer a reclaim service on thin film materials and a recycling service to panel manufacturers. The company plans to open a new US office to house their R&D facilities closer to its principal customers later this year. Tyco displayed a different range of interconnection products using a rib and
Show review: 24th European Photovoltaic Solar Energy Conference & Exhibition
slot system that prevents positive plugs being accidentally inserted into negative sockets. The connector terminals are silverplated screw terminals to protect against tin migration. The division is currently restructuring into a new Alternative Energy Division under the direction of Randy Bahr. GT Solar’s new director of marketing, Jeff Nestel-Patt, told Global Solar Technology about the new factory they have just opened in Shanghai, China. The new facility will be used for maintenance and support, spare parts, training, and testing of customers’ processes on GT equipment. The investment in Shanghai confirms the importance and commitment of GT Solar to the China market. Manz Automation had four new product offerings. The first was an Aerosol Jet used for backside and frontside printing. The second was a new wet processing line fitted with magnetic coupling drives to isolate the drive mechanism from the rollers in the bath and thereby reduce contamination. At the front of the line was a new inline PSG loader using a “Bernoulli” pick up head to feed two or four lanes through the wet processing system. Finally, Manz showed off a Laser Multi Tool, which was originally developed for in-house use and is now being made available to customers. Rehm have been around the PV industry since 2006, providing dryers to Asys. They now want to establish their own brand in PV and demonstrated their dryers and the new, modular RPS Fast Firing System. Rehm claim that faster belt speeds and higher volume equals more contamination in the furnace. Most of these impurities are released in the rampup phase. The Rehm RPS uses a combination of infrared and thermal air through a granulated filter to clean the air. The filters last up to six months and can be inexpensively replenished. IMEC, the Belgian research institute, are working on a range of cell technologies to increase efficiencies and stability. Organic solar cells are one option that are easy to make multi-junction, using the same 3D stacking technologies as chips. IMEC are also working on organic transistors. The projects are part EU funded and supported by Schott Solar, Suez and Total on the materials research and M.E. Baker, Leybold, Roth & Rau and MEMC on the equipment research. Asys had a wide range of new product introductions. The SEL01 electro luminescence inspection system provides a thermal footprint of each cell. The STH01CS test system incorporates laser marking on the
backside of the wafer, offering full traceability of individual cells and batches. The laser marking operates simultaneously with the other test sequences, thereby eliminating any downtime in the test cycle. Asys also introduced their new XSR1 rotary table printer. Stage one performs breakage checks and edge detection. The printer can then use the dimensional information or an image for positioning, offering repeatability of ± 10 µm at 6 sigma. The print head is capable of doing print on print down to 50 µm, selective emitter or metal wrap Through, where the paste is pulled through using a vacuum. Stage three inspects the printed wafer for missing paste, smudges or smears, then the fourth and final increment checks the condition of the paper used as the transport medium and replaces it, where necessary. The XSR1 can print up to 4,600 wph. Asys also introduced a new post-print inspection system for backside printing. The SPC03 DCS is a dual lane configuration with a matrix camera to check for print defects in busbars and fingers. The XS2D screen printer can print up to 3,200 wph at an accuracy of ±12.5 µm at 6 sigma. The printer is fitted with a new transport system, resulting in less travel for the wafer. It also has an edge alignment and centre alignment system. Coming soon will be a new top side vision system that will be retrofittable to existing Asys printers and will enable Selective Emitter and Print on Print applications. Indium Corporation displayed their wide range of CIGS materials in bar, shots and performs for applications on flexible substrates or glass. However, the big news at the show was their acquisition this week of RNT (Reactive Nano Technologies). This is a key strategic acquisition for Indium that complements their sputtering target business perfectly. Indium have the only rotary target that handle copper, indium, gallium and diselenide all in one process step, and RNT claim to have around 50% market share in the sputtering target bonding business. Nanofoil as the name implies is a foil material made up of 1,000 layers of aluminum (Al) and nickel (Ni) that melts at 1200˚C in a fraction of a second, providing localised thermal bonding without allowing sufficient time for thermal transfer to surrounding components. The result is a uniform bondline thickness with minimized stress from CTE mismatches and virtually no voiding. (video) Targray is a single-source raw materials supplier with a global footprint. Over
50% of it’s business is the distribution of silicon feedstock and other materials for C-Si module production. The other part of their business distributes best in class materials such as Peak Sun (founded by John Schumaker) phosphorus oxychloride (POCL3) for inline diffusion and for use in tube furnaces. Targray also sell a range of aluminum (Al) front and backside conductive pastes and the market leading silver (Ag) paste from Heraeus. Another neat product from Targray is the electroformed stencils from Cookson. These enable deeper apertures for taller, narrower, sharper lines, providing higher cell efficiency. Rena introduced a new texturing system. The Intex removes saw damage and textures the surface of the cells. It is considerably faster than it’s predecessor with five lanes moving at 2M per minute and a throughput of up to 3,000wph. The lanes do not have any walls or obstructions between them and the wafers are transported on solid rollers with O rings. The Intex is complemented by a new loader and unloader system and easy to use software system. Applied Materials introduced the Baccini Esatto (Exact). The Esatto is a rotary print platform that can perform print on print down 5 µm providing what AP claims is a 0.5% increase in cell efficiency. The Esatto can also print selective emitter and can print around fiducials. (video) Essemsolar launched the SP-900S printer designed for R&D applications and pilot to small production runs. Its frame is filled with anti-vibration materials to give the rigidity for fine line printing (70 µm line width with an accuracy of ± 8 µm) for print on print. The printer also has a three-stage transport system and easy to use GUI interface. (video) Datapaq presented two new profilers in Hamburg—one is for profiling the lamination process and monitoring glass warpage and the other measures and optimizes the UV curing process. MTA introduced their new Helios 5 automatic tabber and stringer. The system is flux-free and uses thermosonic bonding to create the interconnect on the wafer. That was the highlights of EUPVSEC in Hamburg. Next year the show moves back to Valencia in Spain. A move that could turn out to be a stimulus or an embarrassment for the Spanish government. Let’s hope by then their economy has recovered and the pv industry resumes it’s growth pattern as the most exciting renewable energy source. —Trevor Galbraith.
Global Solar Technology – November/December 2009 – 29
Show review: 3rd Renewable Energy India 2009 Expo Electrical characterization of photovoltaic materials and solar cells
Solar hogs the limelight at 3rd Renewable Energy India 2009 Expo The 3rd Renewable Energy India 2009 Expo held in New Delhi during August 10-12, 2009, had an impressive turnout from around the world, with over 385 exhibitors from 27 countries, 12,000 trade visitors and over 1500 delegates attending the international exhibition and conference. The event, which was organized by the Exhibitions India Group, echoed the mood of the renewable energy industry in India: upbeat, yet uncertain. The participants were very excited about the future of renewable energies but were unsure about the effects of the global recession and the support the renewable energy sector will receive from the Government of India. Speaking at the opening ceremony, Deepak Gupta, India’s Secretary for the Ministry of New and Renewable Energy, said, “The Government is likely to roll out a plan to add 20 gigawatt solar-based power generation capacities by the year 2020. The solar mission has been approved in principle, now we have to work on the roll-out. Hopefully, we will go to the Cabinet in the next couple of months so we can roll out the plan this calendar year.” He stressed the challenges of new and changing technologies and encouraged participants in the exhibition to take advantage of the platform and help meet challenges ahead. Ernst & Young made the theme presentation of the show, which stressed the need to explore the avenues of financing and access to growth capital needed for much needed infrastructure development. It was interesting to learn that the Ernst & Young Renewable Energy Country Attractive Index pegs India at number four globally. The show featured an impressive array of technology from the sectors of solar, wind, hydro, bio, geothermal energy, cogeneration and energy efficiency. There was a
good showing of international companies looking to take part in the future of India’s renewable energy markets. The exhibition hosted pavilions for Germany and the U.S., and there was good attendance from companies representing China and Taiwan as well as a few other European countries. As expected, solar was the predominant sector at the conference; however, representation of wind companies was commendable. The event also hosted a CEO Round Table on financing renewable energy products, highlighting current experiences, challenges, and a roadmap for the future. The interactive and thought-provoking conclave of industry leaders provided insights to this sector, investment outlook and enabling policies for future growth. The Green Jobs Fair 2009 highlighted emerging career opportunities in the renewable energy industry. The Solar Energy Society of India (SESI) conducted a workshop on the latest trends in designing, manufacturing and testing PV modules. The German India Cluster Network also offered a workshop— “Industrial growth, energy efficiency and renewable energies”—as did Structural Solutions, on environmental testing of solar PV modules. The German Federal Ministry of Economics & Technology celebrated the German day at their pavilion on the second day of the expo with enriching presentations by experts from Germany. In a move to integrate the innovators
30 – Global Solar Technology – November/December 2009
of tomorrow with the renewable energy sector, an interactive Youth Summit invited panellists from the industry and academia as well as R&D experts to a discussion on challenges facing the Industry today and how the “Youth [can help] Building a Sustainable Future.” The forum discussed various educational programs and the industry support given to viable green initiatives. Sponsored by Garrad Hassan & Partners Ltd (UK), the Youth Entrepreneurial Green Awards 2009 highlighted innovative concepts and projects, including the display of the Solar powered car. Ten shortlisted projects were on display at the expo; the winner was announced following the Youth Summit. The exhibition concluded on August 12, 2009 with participants looking forward to the Delhi International Renewable Energy Conference (DIREC) 2010, which will be held in the NCR during 27-29 October 2009. The show is a part of the IREC series previously hosted by the governments of Washington, Beijing and Bonn. The 4th global ministerial level conference with concurrent trade show will be organized by the Ministry of New & Renewable Energy (MNRE) and managed by the Exhibitions India Group and expects the participation of 250 speakers, over 500 exhibitors from 40 countries. —Debasish Choudhury
Electrical characterization of photovoltaic materials and solar cells
Global Solar Technology â€“ November/December 2009 â€“ 31
Show review: Solar Power International 09 Electrical characterization of photovoltaic materials and solar cells
Solar Power powers ahead
Solar Power International
October 12-14, 2010 Los Angeles Convention Center, Los Angeles, California, USA www.solarpowerinternational.com
From a manufacturing perspective, Solar Power was more memorable for the sorts of companies that didnâ€™t exhibit, rather than those that did. Sure, the show was very large, filling most of the cavernous Anaheim Convention Center, but the majority of the exhibitors were either panel manufacturers or installers and support services. That said, it is without doubt the biggest event on the US PV calendar and over double the size it was 12 months ago in San Diego. There are very few businesses that have grown by this percentage in the past year. Most of the innovations on the floor had already been demonstrated in Hamburg, but here are a few new ones and some that we missed from our EUPVSEC roundup. GT Solar announced the final sign-off on a new 30 MW multi-crystalline line for DC wafers in Leon, Spain. Illustrating the fast pace of development in the PV industry, the line is expected to exceed specification by as much as 5 MW as the line is already operating at a higher than expected polysilicon consumption rate. Christopher Associates introduced a new Chinese-made framing machine, which they expect to receive UL approval on by Q1 2010. They will also be introducing a new solar simulator soon that is highly efficient and competitively priced. The Orient lamination press introduced at Intersolar in July has just brought out a new multilayer opening press. Techon are targeting the prototype and first pilot market with their range of dispensing solutions for silver epoxy paste. The Techon dispensers have disposable valves, which prevent many of the difficulties associated with cleaning dispenser nozzles. Techon works with most of the major paste and epoxy producers.
Team Technik displayed information on their TT900 and TT1200 stringers. The Team Technik stringers uniquely process the wafer sunny-side down, which minimizes handling. The new TT1200 machine is a dual lane feeding system, ensuring constant production if one lane is down for maintenance. The stringers can be fitted with laser or IR soldering options and both systems test each cell for planarity, breakage and alignment on the busbar. PV Powered claim to have 97% CEC efficiency in their PVP 260 KW inverter system. One of the reasons for their higher efficiency is because their inverters contain the lowest number of parts in the industry. PV Powered can now gang four systems together to create a 1 MW solution that can be mounted on piers and does not require a large concrete pad. Fabrico is a custom materials manufacturer. They make a range of laminated materials for cell production and busbars. Their unique servo-driven motors and pickups enable precise control of tensioning, resulting in optimized efficiency from the material. They also use a unique doublewheel cutter to provide sharp edge definition. Fabrico can cut or stamp materials in any size or configuration. DuPont introduced two new silver metalized paste products to the US market. Solamet PV412 is specifically designed for thin-film applications. Solamet PV173 is a new lead-free and cadmium-free paste. DuPont also exhibited a new back sheet material with improved weatherability using a coating embedded into the polymer. Komax were one of the few companies with machines on the show floor. The new X-2 double stringer offers a dual lane
32 â€“ Global Solar Technology â€“ November/December 2009
configuration. Wafers are transported through the process by a single robot pick that carries it through the fluxing and inspection stages, resulting in less handling and less breakage. The ribbon interconnect uses induction soldering and closed-loop software for thermal profiling. Edwards produces pumps for sputtering lines and gas abatement systems to clean up some of the nasty gases associated with the CVP process. Edwards has a global footprint of sales and service around the world and focus on reducing the energy costs associated with the many pumps utilized in a typical PV plant. XsunX emerged from the hard disk drive industry with a new system for replicating lab efficiencies on the production floor. The system produces around 600 wafers per hour and fits within a 25 ft footprint. At the heart of the system is a highly stable platform that uses sensors to measure pressure across the wafer and monitor the gas flow rates. XsunX partners with Innovac to create the materials handling tools, while XsunX provides the deposition technology. The company is looking to license the technology in the future, while providing field service, consultancy and training. 3S is one of the original manufacturers of solar laminators back in 2001. Since then, they have acquired Pasan testers and Sonot, the manufacturer of stringers to provide a full turnkey capability of systems from 50Mw to over 200 MW. The Swiss engineered systems use an overhead gantry as opposed to a robotic system, which they claim works at a finer tolerance. The glass is carefully measured at the start of the Continued on page 37
Electrical characterization of photovoltaic materials and solar cells
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Global Solar Technology â€“ November/December 2009 â€“ 33
New Products Electrical characterization of photovoltaic materials and solar cells
New products Essemsolar’s Econoline prints fine structures onto solar wafers With a repeatability of 8 μm, Essemsolar’s Econoline, a new printing system for the solar industry and thick film technology, is the world’s most accurate screenprinting system in its range. Econoline prints and stacks fine structures precisely, with thinner and higher conductor lines, for more efficient solar cells. Perfect for development, laboratories and small series manufacturing, in consists of Essemtec’s automatic screen printer SP099-S, an inline curing system, and magazine handlers. The line is very flexible: wafers from 100 x 100 to 210 x 210 mm can be processed, and screen frames from small to 29 x 29“ can be used. Typically, it is operated in batch mode where several magazines are handled at both ends of the line and processed automatically. www.essemtec.com
Solamet® PV412 photovoltaic metallization specifically for thin film solar DuPont Microcircuit Materials introduced DuPont™ Solamet® PV412 photovoltaic (PV) metallization paste, the latest in a line of silver conductor materials specifically developed for thin film PV technologies. DuPont collaborated with Ascent Solar Technologies, Inc. (ASTI), a developer of state-of-the-art flexible thin-film solar modules, as it developed Solamet® PV412. The new paste is designed for use on devies where a transparent conductive oxide is utilized. It is ideal for use with CIGS, a-Si on flexible substrates, and heterojunction with intrinsic thin layers (HIT) PV cells, and also suitable for any PV application where a low temperature curing conductor is required. photovoltaics.dupont.com
solar cell encapsulation technology that improves performance and effectively lowers the cost per kilowatt-hour of solar power. The Dow Corning® PV6100 encapsulant series relies on the UV stability of the silicone molecule to deliver improved durability and increased efficiency for crystalline modules compared to incumbent organics. It provides an ultratransparent layer of protection for the solar cell in a panel and can replace incumbent technologies. Users of the silicon-based material can expect higher efficiency, longer module life, and optimum UV resistance. www.dowcorning.com
Expanded Enduro™ coatings platform Greene, Tweed announced its newly expanded Enduro™ platform of protective coatings for the semiconductor and solar industries. Leveraging industry-leading materials and coating processes, these new capabilities provide superior component protection in a variety of chamber environments. Greene, Tweed coatings are
amorphous, dense and micro conformal materials that are deposited on a variety of vacuum compatible substrates including metals, alloys, ceramics, and polymers using proprietary, low temperature processes. These processes allow for coating of temperature sensitive substrates and, with eight distinct coatings, the platform offers highly beneficial properties for use in variety of semiconductor and solar environments. www.gtweed.com Multiple printing capability for producing higher efficiency solar cell Applied Materials, Inc.’s Baccini Esatto Technology™ offers high precision, multistep screen printing capability for Applied’s market-leading Baccini back-end solar cell processing systems. Featuring proprietary hardware and software innovations, the Esatto Technology is designed to increase the efficiency of crystalline silicon (c-Si) solar cells by enabling the fabrication of advanced contact structures. The first of several applications of the Esatto Technology is for double-printed metal line deposition where it has been shown to raise absolute cell efficiency by as much as 0.5%. www.appliedmaterials.com Innovative edge isolation improves solar cell efficiency throughput Schiller Automation GmbH & Co. KG and Merck KGaA are constructing an innovative line for edge isolation of
Breakthrough solar cell encapsulant technology lowers cost per kWh Dow Corning Corp. announced the commercial availability of a breakthrough
34 – Global Solar Technology – November/December 2009
crystalline silicon wafers. SolarEtch® SiD from the isishape® etching paste program developed by Merck will be used in the novel process. Laboratory tests on several thousand wafers have successfully confirmed an increase in overall efficiency through the use of innovative SolarEtch® materials. The process offers numerous advantages over traditional edge isolation methods, in particular comprehensive wet chemical isolation and laser isolation. With the newly developed application concept, isishape SolarEtch® SiD can be applied to the back of the wafer quickly and selectively. www.schiller-automation.com Calibration & quality control for solar module manufacturing Sensor Products Inc. introduces Pressurex®, a pressure indicating film that reveals pressure magnitude and distribution between any contacting or mating surfaces. In the photovoltaics industry, the need to reduce peripheral cracks on solar cells has received much attention. Thin film modules of CDTE or CIGS on glass or flexible substrates are particularly susceptible to moisture ingress and require stringent quality control checks. Pressurex® provides a low cost solution for quality control checks during equipment setup, calibration and requalification of a solar module production line. Negative occurrences such as cracked substrates, squeeze out of materials from the module and unwanted encapsulant thickness can be reduced, if not eliminated, by measuring and optimizing the quantity of applied pressure. Pressurex® uniquely provides a quick and low-cost solution for measuring applied pressure magnitude and distribution. When placed at the interface of two contacting surfaces that are compressed together (as in a lamination or heat press for example), Pressurex® measures pressure from 2 - 43,000 PSI (0.14 - 3,000 kg/cm²). www.sensorprod.com New firing systems for solar cell metallization Rehm Thermal Systems announced the launch of an advanced new series of firing systems for solar cell metallization to complement their recently updated line of drying systems. The RFS and RFS-D Fast Firing Systems and the RDS 2100 and 3000 drying ovens feature Rehm’s Visu2 software, which drives a range of advanced process features and thermal control to enable PV manufacturers to move their processes to an entirely new level of efficiency and yield. Visu2 incorporates
New Veeco advanced dicing system Veeco Instruments Inc. introduced its Optium® ADS-800™ series advanced dicing system, delivering high productivity dicing solutions for a broad range of demanding applications, including solar cells. The ADS-800 offers superior and repeatable cut quality of devices at unprecedented throughput as compared to other dicing systems. The system is suited for R&D environments, pilot line production and high volume production. www.veeco.com
process and product traceability tools, remote diagnostics and an extensive product library within an intuitively designed interface that dramatically accelerates set up time and reduces operator training. www.rehm-group.com Scaling up solar manufacturing processes with Hypersonic Sono-Tek Corporation’s new HyperSonic ultrasonic reciprocating coating system, designed for processes such as phosphoric doping, CIGS coatings, anti-reflection coatings and various nanosuspension coatings for thin film and silicon solar cell production, features uniform deposition of thin film layers with excellent stiction properties and durability. Capable of reciprocating speeds up to 79 inches/sec (2 meters/sec), HyperSonic is available in three sizes—48 inch (122 cm), 38 inch (97 cm) or 24 inch (61 cm) width coverage— and offers full PLC process control. www. sono-tek.com
& defect inspection, processed cell front/ back side printing & defect inspection and CIELAB color classification. www.chromaus. com Dow Corning offers new adhesive, sealant Dow Corning has expanded its portfolio of materials developed for the specific needs of the PV industry with the addition of Dow Corning® PV-8303 Ultra Fast Cure sealant and Dow Corning® PV8030 adhesive for bonding and sealing photovoltaic module components. Dow Corning® brand adhesives and sealants for solar applications are designed to provide long-term bonding and protection against moisture, environmental degradation, mechanical and thermal shock. Dow Corning® PV-8030 adhesive is an easy-touse, one-part material ideal for
Solar cell inspection and test product line Chroma ATE has begun rolling out a collection of inspection modules and automated test solutions designed for characterizing, validating and testing mono and multi-crystalline silicon cells. Each of the inspection modules and test solutions may be easily integrated into an existing production line or configured as a turnkey automated production solution with Chroma’s automated handling systems. The automated inspection modules provide solar cell raw wafer dimensional
Global Solar Technology – November/December 2009 – 35
1366 Technologies’s breakthrough solar cell architecture enables record efficiencies 1366 Technologies unveiled two breakthrough technologies for multi-crystalline silicon solar cells. The company’s significant advancements in cell texturing and metallization deliver simpler, more commercially viable solutions for multi-crystalline cell manufacturers striving to reach 18 percent efficiency. 1366 Technologies’ Self-Aligned Cell (SAC) architecture breaks the historic efficiency and cost tradeoff of photovoltaics (PV) by providing mono-crystalline equivalent cell efficiencies at multi-crystalline cell costs. For years, many PV companies have tried to increase efficiencies by using overly-complicated approaches, such as back-contact or emitter wrap through solar cell technology, which add costly steps to the manufacturing process with minimal gains in cell efficiency. This problem slowed the pace of progress until MIT professor, renowned inventor and 1366 Technologies Chief Technology Officer, Dr. Emanuel “Ely” Sachs, developed a simple, cost-effective approach to improving cell texturing and metallization without increasing production costs. “At 1366 we’ve pioneered a cell architecture and manufacturing process that’s going to change the way we think about energy,” said Frank van Mierlo, co-founder and president of 1366 Technologies. “Our innovations have the potential to save manufacturers $50 billion over the next five years and help the industry deliver solar at the cost of coal.” 1366 Technologies has developed two technologies that can be easily integrated into existing manufacturing lines. The first addresses cell texture, creating a distinctive honeycomb structure that introduces cross-textured surfaces to the cell that trap more light and enable up to 1 percent higher absolute efficiency overall than previous cell designs. The second focuses on the front-side cell metallization, wherein the company has developed the world’s finest metallization lines—just 30 microns compared to the prevailing 120 microns—and an innovative Grooved Ribbon busbar (licensed by Ulbrich and Schlenk). Industry standard thick fingers and flat busbars typically shade 9 percent of the surface of a cell. 1366’s simple front-side metallization approach, however, only shades 2 percent of the cell delivering 75 percent of the efficiency gains of back-contact cell designs without the high costs and process complexity. “The way we see it, the right technology and materials are available now to help PV reach grid parity, but the challenge for our industry is to simultaneously deliver high efficiencies and low costs,” said Dr. Emanuel Sachs, co-founder and chief technology officer for 1366 Technologies. “Our Self-Aligned Cell architecture addresses this challenge head-on. We believe our technologies, combined with further advancements in manufacturing, will help solar power satisfy 7 percent of global electricity demand over the next decade and inspire one of the largest manufacturing revolutions in history.” www.1366tech.com
rail bonding applications where roomtemperature curing is preferred. Dow Corning® PV-8303 Ultra Fast Cure Sealant is a two-part material ideal when fully automated production is desired. www.dowcorning.com Solution X cuts ink and paste costs by up to 75 percent Solution X from DMRPCB.com is a new solar conductive ink additive that lowers the resistance of silver inks or pastes by a factor of four. Lower resistance ink means a savings of up to 75 percent on ink costs because you use les to create the same current carrying abilities. In the latest round of testing, Solution X lowered the resistance of three different manufacturers’ silver inks to levels below the bulk resistance of copper. A back to back test
of ink as supplied and with Solution X added showed between 3.5 to 5.2 times lower resistance. The very small particles in Solution X do not affect solderability nor do they affect the adhesion of any silver ink property except to lower the resistance. The particle size in solution x is small enough to not effect screen printing or ink jet application of the silver inks. Solution X also works for other metals conductive inks; a simple test will determine compatibility. www.dmrpcb.com Customized vacuum pump systems for PV processes The Oerlikon Leybold Vacuum team has developed special computer assisted tools (LeyCat) to design optimum customized pumping systems in combination with their application know how and
36 – Global Solar Technology – November/December 2009
experience. One such example is the economic and robust SOGEVAC/ RUVAC combinations. The production proven system has been designed especially for fast pump down cycles, offering the perfect solution for load lock and light duty applications. Due to the SOGEVAC type primary pump, it offers high suction speed from atmosphere and low power consumption and maintenance intervals like dry pump systems guarantees economic operation. The system is available in modular packages from 500 to 2000 m³/h pumping speed. www.oerlikon. com In–situ XRF yield management tool for CIGS composition and thickness measurement Solar Metrology expands its SMX XRF tool portfolio for film composition and thickness measurement of CIGS photovoltaic depositions with the addition of the System SMX-ISI, an in-situ x-ray fluorescence (XRF) metrology tool platform that provides composition and thickness measurements for thin film solar PV metal film stacks on flexible roll to roll substrates such as stainless steel, aluminum and polyimide or rigid substrates such as float glass. Typical measurement applications include Mo thickness and all CIGS combinations (including all CIG alloys and/or film combinations and final CIGS formulations). SMX-ISI is fast, flexible and easily integrated into any vacuum deposition tool or vacuum process station or point of a vacuum process line. www.solarmetrology.com Sawn waver blocks pre-washed and debonded Schmid Silicon Technology presents an innovative, gentle cleaning process for pre-washing wafer blocks and debonding them. Previously, waver blocks were prewashed only in so-called batch processes and subsequently debonded with acid, i.e. the glass carrier detached from the silicon. Narrow kerfs and thin cutting wires made the cleaning task with spray heads increasingly more difficult and costly. In close mutual cooperation with the Swiss company N. Bucher AG—inventor and distributor of the ceramic carrier plate, which replaces the glass plate in wire sawing—the Schmid Group has developed a completely new inline cleaning concept. The sawn wafer block is moved inline on a carrier through the system. The cleaning process takes place directly in the cutting gap with the aid of special ceramic carrier plates. In addition to an increased
yield of wafers in this process step, the partners Schmid and Bucher are counting on substantial improvements with the bonding, separation and final cleaning processes. www.schmid-silicon.com
New 525W DPSS laser delivers high reliability for solar cell processing The new Mamba™ from Coherent Inc. is a 525 Watt (at 1064 nm), diodepumped, solid-state laser that delivers an unmatched combination of high reliability, long lifetime and minimal maintenance downtime. It is primarily intended for high throughput materials processing applications such as edge deletion of solar panels and ITO patterning. The exceptional reliability of the Mamba derives from several factors including
PermAlign construction for drift-free, long term alignment of its resonator optics, pump diodes fabricated using Coherent’s long lived AAA™ material, and indiumfree hard solder pump diode packaging for extended lifetime. www.Coherent.com Secure transport packaging for solar wafers Christian Senning Verpackungsmaschinen GmbH & Co. KG, Bremen launched a new foil wrapping machine for the packaging of highly sensitive wafers and solar cells to secure them during transportation and prevent breakage. The new Senning Packaging Machines packaging line guides stacks of wafers and solar cells with high precision. Semi- and fully-automatic solutions are available. www.senning.de Increased productivity of solar ingot squaring Applied Materials Inc’s new Applied HCT Diamond Squarer™ system is capable of reducing the cost of squaring silicon ingots by up to one-third while offering at least twice the cutting speed of conventional
squaring processes. Key to the HCT Diamond Squarer’s high performance is its novel diamond wire technology that eliminates the need for abrasive slurry and cuts electricity consumption in half. The compelling benefits of diamond wire are also available for Applied’s currentlyinstalled HCT Squarer systems as a cost-effective, easily deployable upgrade kit. www.appliedmaterials.com New CILS security labels with ultra aggressive adhesive Computer Imprintable Label Systems (CILS) has launched their new CILS 8200V/HT label construction which features a fast curing high-strength adhesive for immediate voiding, making the labels ideally suited to textured, aggressive, curved or oily surfaces. These new high performance labels also withstand fuel, oil, dirt, abrasion and jet washing, as well as extreme temperatures of –55°C to +155°C. CILS range of tamper resistant labels, display a ‘VOID’ message to show immediate indication of tampering to help prevent any fraudulent tampering or relabelling. www.cils-international.com
Solar Power powers ahead— continued from page 32
Silicon solar cell efficiency & thermal process optimization in the metallization process—continued from page 8
process and the information passed to each production cell on the way through the process. The newest machine in the 3S stable is the XL laminator. A 3-chamber, horizontal laminator that competes against stack laminators. 3S claim that the critical pre-cure phase improves the curing cycle and increases throughput to a cycle time of around five and a half minutes per four modules. Madico exhibited their new Bright White technology, a back sheet with a pigmentable EVA layer that reflects light back in between the fingers for up to 5% additional conversion. And finally, Dr Schenk provides the full spectrum of metrology measurement tools into many of today’s leading edge PV systems. The company’s software also provides closed-loop SPC and reporting systems. Next year Solar Power moves to downtown Los Angeles. Book your booths and hotels early. This PV show shows no signs of slowing down. —Trevor Galbraith.
TCs in place, rather than to measure the surface of the wafer. Pinning the TC to the wafer with a weight suffers from nonrepeatability. The fixture with flattened TC beads has worked well for us. Finally, process optimization must be quick and easy enough to be useful for volume production lines, as opposed to only the laboratory line. There is little use in perfecting the process in the laboratory just to see the transfer to the production lines fail because the furnace properties are different. Once the correct process window is established, the high-volume furnaces can be adjusted within minutes, keeping production downtime to a bare minimum. This task must not only be performed during transfer from the lab to the production line, but it also must be performed periodically due to the drift in the thermal process that is a fact of life in any production line. The few minutes it takes to adjust the production furnaces for peak performance is richly rewarded by the ability to consistently produce higher efficiency cells.
Future studies The temperature readings taken by the e-Clipse TC attachment fixture are higher than historic readings taken by older TC attachment methods. A future study will focus on quantifying the accuracy and repeatability of the new profiling method as it relates to the theoretical true wafer surface temperatures.
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Industry News— continued from page 5 Applied Nanotech selected to receive funding for the development of solar technology Applied Nanotech Holdings, Inc., has been selected by the U.S. Department of Energy to receive a contract of approximately $750,000 for the development of noncontact, printable metallic inks for silicon solar cells. During this two year Phase II Small Business Innovation Research program, Applied Nanotech will focus on improving methods for the application of metallic electrodes to silicon photovoltaic (PV) substrates using its unique metallic nanoparticle-based inks. Electrical contacts are a critical part of PV technology and represent a difficult and costly area for solar cell production. This development program will exploit advances in nanotechnology to lower manufacturing costs and improve solar cell efficiency. This program is particularly important since using very thin silicon wafers in an effort to reduce silicon usage has resulted in wafers that are susceptible to breakage when utilizing traditional contact printing methods such as screen printing. www. appliednanotech.net DuPont to invest $120 million to increase capacity for Tedlar® photovoltaic module materials DuPont is investing more than $120 million in a multi-phase production expansion for its high-performance DuPont™ Tedlar® polyvinyl fluoride (PVF) product line. This phase of the expansion increases, by over 50 percent, the capacity of monomer and resin used in producing Tedlar films, which serve as the critical backsheet component, providing long-term durability for photovoltaic modules in all-weather conditions. Site selections for this phase of the Tedlar capacity expansion are complete, and construction has begun for new monomer and resin facilities at the DuPont Louisville, Ky., and Fayetteville, N.C., sites, respectively. The facilities are scheduled to start up in mid-2010. photovoltaics.dupont. com Xunlight delivers first shipment of flexible solar modules from 25MW production line Xunlight Corporation, the University of Toledo (UT) and the Ohio Department of Development (ODOD) jointly announced today that Xunlight has delivered its first shipment of flexible and lightweight,
addition to his new responsibilities. www. deksolar.com
triple-junction amorphous silicon solar modules manufactured on its newly installed 25 megawatt wide-web roll-to-roll PECVD production line. This shipment of modules is part of a 10 KW solar array to be installed at UT’s Scott Park Campus of Energy and Innovation (SPCEI). This shipment of modules represents the first sale produced using its proprietary 25MW wide-web, roll-to-roll PV manufacturing equipment, which is redefining the industry as a low-cost, high-throughput solution to large-scale solar cell production. The 25MW solar cell manufacturing equipment, a 200-feet long series of connected vacuum deposition chambers, uses a plasma enhanced chemical vapor deposition process to deposit thin-film silicon solar cells on a 3ft wide, one-milelong thin stainless steel substrate at a speed of 720-square feet per hour. This manufacturing process is inherently lowercost and more productive than competing technologies, and is designed, developed and constructed by Xunlight Corporation. www.xunlight.com DEK Solar taps Andy Ure to spearhead Americas business development DEK Solar appointed Andy Ure to the position of alternative energies business development manager for the Americas. Ure, whose career spans more than 20 years at DEK, has held numerous roles within the company and has been instrumental in bringing several technologies to the fore. Not only does he have extensive field service engineering and applications engineering experience as a foundation, Ure was also part of the development teams for DEK’s awardwinning ProFlow™ enclosed print head technology and its Virtual Panel Tooling (VPT) singulated substrate handling system, in addition to contributing to multiple next-generation ball attach solutions. Currently, Ure serves as business manager for one of DEK’s top customers—a role he will maintain in
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BTU International obtains ISO 9001 Certification for its Shanghai manufacturing operations BTU International, a supplier of advanced thermal processing equipment for the alternative energy and electronics manufacturing markets, has completed ISO 9001:2008 certification for its Shanghai manufacturing operations. BTU’s Shanghai facility serves as the company’s Asia Pacific headquarters and comprises manufacturing, engineering and process development functions, in addition to sales and service. The facility houses BTU’s first Center of Excellence for Photovoltaics Manufacturing Technology, dedicated in 2008, and is located in the heart of the Chinese solar manufacturing industry. www.btu.com LDK Solar partners with Yancheng City on PV projects LDK Solar Co., Ltd., a manufacturer of multicrystalline solar wafers, has entered into an agreement with Yancheng City of Jiangsu Province for the development of PV power projects. According to the agreement, LDK Solar will develop a number of PV power projects, including PV ground-power stations, and roof and building integration systems totaling up to 500 MW over the next five years. The terms, including financing, design and specific location of each of the projects, will require a feasibility study as well as final approval from relevant state departments prior to initiation. www. ldksolar.com Baoding Tianwei starts mass production of thin film solar panels with Oerlikon solar technology As China boosts solar energy to meet growing power demand and reduce dependence on imported fuels, Tianwei and Oerlikon Solar announced the completion—ahead of schedule—of one of the mainland China’s largest thin film solar panel factories. This first phase of the Tianwei project produces 500,000 modules per year, which generates a total of 46 megawatts of power. Tianwei is using Oerlikon Solar’s Amorph High Performance PV technology for Phase 1. www.btw-solarfilms.com, www.oerlikon.com US solar PV equipment market to generate $347.90 million by 2013 The US federal government has provided funding of $3.1 billion to the states as
part of its economic stimulus package, to encourage PV installations and expand solar PV support programs. The government has also extended federal tax credits for solar PV. These support mechanisms combined are expected to open up high-growth markets for PV equipment such as inverters and modules. According to the new GlobalData’s report, “The Future of the US Solar PV Equipments Market,” available from Research and Markets, the PV inverter market in the US is expected to generate an estimated $347.90 million by 2013, while the modules market is expected to generate $2,741 million by 2013. www. researchandmarkets.com Ascent Solar internally certifies module encapsulation material for its flexible PV laminate Ascent Solar Technologies, Inc., a developer of flexible thin-film solar modules, has internally qualified a packaging solution for its flexible monolithically integrated CIGS modules. In internal qualification testing, its flexible packaging solution successfully passed the rigorous standard of one thousand (1,000) hours of damp heat testing (85% relative humidity and 85°C temperature) guideline set forth by IEC 61646 standards for performance and long term reliability of thin film solar modules. This sets the stage for certification of Ascent Solar’s products by external agencies. www.ascentsolar.com Australia gives funding boost for solar industry The Australian Solar Institute (ASI) has launched a grants program for solar energy innovations, starting with a first round worth $1 million for basic research and up to $5 million for applied research. Earlier this week, Minister for Resources and Energy Martin Ferguson met with the ASI board and welcomed the program. “Supporting research and development
in both photovoltaics and concentrating solar thermal is fundamental to building Australia’s expertise and capacity in this industry,” he said. “Australia has the potential to be a world leader in the development of solar energy. As well as benefitting the environment, there are huge business opportunities and significant export earnings.” Siemens invests US $15 million in Israeli solar company Arava Power German industrial conglomerate Siemens is investing $15 million in Arava Power Company, the Israeli market leader in developing solar power plants. An agreement signed at Kibbutz Ketura secured Siemens a 40 percent stake in the company. Arava Power develops, builds and operates photovoltaic plants in Israel. The equity investment will make it possible to build Israel’s first commercial solar farms, to be located in the region between the Dead Sea and the Red Sea. www.siemens.com, www. aravapower.com KYOCERA Sakura Solar Energy Center marks 25 Years Since 1975, Kyocera Corporation has continuously been developing its solar energy business with the business rationale “To bring the power of the sun to the world.” To achieve that goal, in August 1984, Kyocera established the Sakura Solar Energy Center just outside of Tokyo for the research & development, and promotion of solar power generating systems. This year, the center marks its 25th anniversary. At the time of the establishment of the Sakura Solar Energy Center in 1984, use of solar power generating systems was limited to special applications such as unmanned lighthouses, satellites and wireless repeater stations. The concept behind the
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establishment of the center was to create a comprehensive facility at which to conduct research into solar power products and to facilitate understanding of the benefits of solar energy by introducing it to the world. The center is conveniently located close to Narita International Airport—the gateway to Japan—in Sakura City, Chiba Prefecture. In the 25 years since it was established over 50 thousand visitors have come to the center to learn about solar power technology. global.kyocera.com China Nuvo Solar Energy acquires additional photovoltaic intellectual property China Nuvo Solar Energy, Inc. has acquired from Photovoltaics, Inc. a variety of solar technologies/inventions consisting of six provisional or utility patents. This newly acquired intellectual property relates to enhancements of currently available technologies ranging from increases in output and efficiency to the use of lower cost newly discovered photovoltaic materials and processes. The Company believes that each of the technologies have the potential, when commercialized, of reducing the cost per kilowatt hour of solar energy, thereby making it more competitive with other energy sources. China Nuvo is in the process of finalizing utility patents for those that are currently provisional. www.chinanuvosolar.com aleo solar AG supplies modules for Zugspitze solar power station aleo solar AG is supplying premium modules for the highest solar power station in Germany. The first aleo modules have been installed on the topmost station of the Zugspitze cogwheel train. ILIOTEC Solar GmbH, one of aleo solar AG’s longstanding customers, is the general contractor for installation and maintenance. The Zugspitze facility is just one of 30 projects covered by the “Solarfonds Garmisch-Partenkirchen 2011” fund. The overall project, to be installed on rooftops throughout the GarmischPartenkirchen region, will include around 1,000 kilowatts of aleo modules. aleo solar AG will be supplying the overall project with aleo S_16, aleo S_18 and aleo S_24 modules. The scope of delivery also includes inverters. www.aleo-solar.de Evergreen Solar and Jiawei Solar hold ceremonial groundbreaking at Wuhan, China manufacturing plant In a ceremony in Wuhan, China, Evergreen Solar, Inc., and its contract manufacturing partner, Jiawei Solarchina Co., celebrated the groundbreaking for
Film GmbH. Bosch Solar Energy is also changing all of its product labeling. www. bosch-solarenergy.de
their new 100 megawatt manufacturing plants. Construction is on schedule to be completed by spring 2010. These manufacturing plants are part of an agreement between Evergreen Solar and Jiawei through which Evergreen Solar will manufacture String Ribbon™ wafers using its state-of-the-art Quad furnaces at this leased facility being built on Jiawei’s campus. Jiawei will convert the String Ribbon wafers into Evergreen Solar-branded panels on a contract manufacturing basis. www.evergreensolar. com, www.solarchina.com.hk Non-active materials will play a major role in improving solar modules, says Lux Research In the solar industry’s race to reach grid parity, the focus has been on active semiconductor materials like silicon and cadmium telluride. However, non-active materials—all of the other components of a solar panel—offer opportunities to reduce overall module cost, and present a large and growing market, according to a new Lux Research report. Titled “Driving Down Solar Costs: Nonactive Material Opportunities,” the report examines new and incumbent non-active materials technologies such as metallization, antireflection (AR) coatings, encapsulants,and transparent conducting oxide (TCO) replacements. While these components don’t directly convert sunbeams to electrons, they can still significantly impact both the cost and efficiency of today’s modules. www. luxresearchinc.com ersol Solar Energy becomes Bosch Solar Energy ersol Solar Energy AG has changed its name to Bosch Solar Energy AG. The three ersol subsidiaries are being renamed at the same time. Ingot and wafer manufacturer ASi Industries GmbH becomes Bosch Solar Wafers GmbH. ersol Crystalline Modules GmbH now operates under Bosch Solar Modules GmbH. Finally, thin-film module manufacturer ersol Thin Film GmbH is trading as Bosch Solar Thin
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BioSolar strengthens analytical laboratory capabilities BioSolar is expanding its analytical laboratory capabilities with the addition of testing equipment from machinery and equipment maker Mocon, Inc., for measuring water vapor transmission rate, a critical property of BioSolar’s innovative bio-based backsheets. Currently, the company’s complete line of biobased backsheets, meet or exceed the characteristics of various testing and performance standards for the PV industry and are expected to cost significantly less than petroleum-based backsheets currently in use by the majority of solar module manufacturers today. www.biosolar.com SMA aquires OKE’s module inverter technology SMA Solar Technology AG announces the acquisition of the module inverters (micro-inverters) technology platform from the Dutch company OKE-Services. In the coming years, SMA will continue to develop this technology and launch its own module inverter product range. Both parties have agreed to keep the exact purchase price confidential. www.SMA.de Solar cell shipments in Japan hit record high in April-June 2009 Demand for solar cells has been growing rapidly in Japan with a record generating capacity of 83,260 kilowatts shipped to the domestic market between April and June, up 82.5% from the same quarter last year, a private-sector survey showed Sunday. The survey by the Japan Photovoltaic Energy Association said over 90 percent of the solar cells shipped during the quarter were for individual household use, indicating that approximately 20,000 households installed solar power generation systems over the period. www.jpea.gr.jp [Source: Japan Today] First Solar to produce twice as much as leading crystalline solar module suppliers in 2009 Leveraging its low-cost thin-film process, U.S.-based First Solar Inc. is set to surpass its crystalline competitors to become the world’s largest producer of PV cells in 2009, according to iSuppli Corp. First Solar is set to produce 1,100 MW worth of solar cells this year, more than double the 503 MW it made in 2008. This will give First Solar nearly twice as much
production of total solar cells as its nearest competitor, Suntech Power Holdings Co. Ltd. First Solar will be the only company among the Top-4 solar cell suppliers able to gain market share in 2009, iSuppli predicts. The company’s portion of global solar cell MW production will rise to 12.8 percent in 2009, up from 7.5 percent in 2008. No.-2 SunTech, No.-3 Sharp and No.-4 Q-Cells all will suffer contractions in total solar cell market share. First Solar also holds the lowest levels of inventory in the global solar cell industry. Because of this, iSuppli expects the company to actually sell all of its production in 2009, rather than stockpiling it. www.isuppli.com Showa Shell to build 3rd solar cell plant Showa Shell Sekiyu K.K.’s wholly owned subsidiary, Showa Shell Solar Co., will build a third plant for thin-layer photovoltaic cells in Miyazaki Prefecture at a cost of 100 billion yen to beef up its solar cell business. The new plant will be capable of producing 900 megawatts of solar panels a year when it is completed in July 2011, boosting Showa Shell Solar’s total output capacity to 1,000 megawatts, the parent company said. It will begin operating with a workforce of around 800. For the investment project, Showa Shell Solar will buy an idle plant in the town of Kunitomi in the prefecture, together with its land of 400,000 square meters, from Hitachi (NYSE:HIT) Plasma Display Ltd. and install manufacturing facilities there. The company is operating two plants for solar panels using compounds incorporating copper and indium, both also located in the southwestern Japan prefecture. [Source: iStockAnalyst] Solyndra breaks ground on new 500 megawatt solar plant Solyndra, Inc., commenced construction of its second solar panel manufacturing plant (Fab 2), located near its current manufacturing facility in Fremont, California. Fab 2 is designed to produce 500 megawatts per year, enabling Solyndra to fulfill its announced contractual backlog of over US $2 billion and create additional jobs. Solyndra’s two Fabs will produce enough solar panels over their lifetime to cut over 350 million metric tons of CO2 emissions or 850 million barrels of oil. www.solyndra.com MEMC consolidates wafer manufacturing operations MEMC Electronic Materials, Inc., plans to cease production of silicon crystal
ingots and wafers at facilities in Sherman, Texas and St. Peters, Missouri. These closings will occur in stages during 2010 and early 2011, as production shifts to other locations. “We must continue to aggressively drive all unnecessary costs out of the business during these extraordinary times,” said chief executive officer Ahmad Chatila. “We will be shifting this highvolume production closer to a number of our customers, who are located in lower cost regions. This will allow us to reduce manufacturing costs and to serve our customers effectively, with the right costcompetitive capacity—in the right places—to meet their needs.” The company is putting severance and assistance programs in place for those employees who will not continue with MEMC. The actions at the two sites are expected to affect approximately 540 employees in the U.S. A small number of these affected employees will be offered positions at other MEMC locations. www. memc.com GT Solar opens new Asia headquarters in Shanghai GT Solar International, Inc., a provider of specialized production equipment, process technology and turnkey manufacturing services for the solar power industry, formally opened its new Asia Headquarters in Shanghai, China. The new facility reduces the time it takes for Asian companies to obtain products, spare parts and service. It will also be used to provide product demonstrations and training to customers in the region. The 50,000 square foot facility represents a significant expansion of GT Solar’s presence in Asia, which was first established in 2006. www. gtsolar.com irst Solar secures US $300 million revolving credit facility First Solar Inc. has entered into a $300 million senior secured revolving credit facility with a syndicate of nine leading financial institutions. The facility, which was oversubscribed, has a three-year term and is intended to be used for general corporate purposes, including the issuance of letters of credit. J.P. Morgan Securities Inc. and Bank of America/Merrill Lynch served as joint lead arrangers and book runners for the facility. www.firstsolar.com LDK Solar to cooperate with Best Solar on downstream PV projects LDK Solar Co., Ltd., has entered into a framework agreement with Best Solar Co., Ltd. to cooperate on downstream PV projects. Under terms of the agreement,
LDK Solar will supply the solar wafers and Best Solar will manufacture the solar modules. “Although we have established a PV engineering company to construct solar power stations in and outside China, we have not yet engaged in any substantial downstream PV businesses, such as solar cell or module manufacturing, solar panel assembly or provision of certain solar utility services,” stated Xiaofeng Peng, Chairman and CEO. “Best Solar, on the other hand, is a large manufacturer of solar modules and a significant provider of solar panel solutions. Additionally, Best Solar is in possession of the relevant product certifications in several jurisdictions. In order to take advantage of the opportunities created by the latest PRC government policies to financially support the construction and operation of PV power stations in China, LDK Solar and Best Solar have agreed to cooperate with each other, by taking advantage of our respective complementary strengths in the different sectors of the PV industry, in order to achieve mutually beneficial results under the current market conditions.” Best Solar is wholly owned by LDK New Energy Holding Limited, which is LDK Solar’s controlling shareholder, and wholly owned by Mr. Xiaofeng Peng, chairman and chief executive officer of LDK Solar. Best Solar has agreed to provide the solar manufacturing services to LDK Solar at comparable pricing to independent third parties for similar quantity and quality. To know more about LDK Solar, visit www. ldksolar.com. Oerlikon Solar customer Astronergy seals major 2 megawatt PV contract Oerlikon Solar customer Astronergy (also known as Chint Solar), a Chinese manufacturer of thin film PV modules, has secured a deal to deliver a two-megawatt rooftop PV installation for the Huangzhou Energy and Environment Industrial Park in Zheijang. Astronergy will design and install the whole project with a combination of crystalline silicon-based modules and highefficiency tandem thin film PV modules. Astronergy is using Oerlikon Solar’s Micromorph® high-efficiency tandem PV technology for this latest project. www. astronergy.com, www.oerlikon.com/solar FCanadian Solar announces 10 MW cooperation MOU with LG in Korea Canadian Solar Inc. entered into a second memorandum of understanding with LG CNS Co. Ltd., a subsidiary of the LG Group of South Korea, to implement a minimum 10 MW of PV power projects in
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Korea in 2010. Canadian Solar modules will be used in these projects. LG CNS has been a customer of Canadian Solar since early this year. This non-binding memorandum expands on the first memorandum of understanding between Canadian Solar and LG CNS signed in April of this year. www.canadian-solar.com Distributed solar energy market to reach US $55 billion by 2012, says Pike Research Distributed energy generation, using a variety of renewable power technologies, is one of the most important tools for addressing the challenge of meeting the world’s growing electricity demands. Within the renewable distributed energy generation (RDEG) market, sub-utility scale solar PV systems are by far the largest and most significant segment. According to a recent report from Pike Research, the distributed solar energy market is poised for dramatic growth over the next few years. The cleantech market intelligence firm forecasts that global installed capacity will approach 2.5 gigawatts by 2012, with annual system revenues surpassing $55 billion. Distributed solar PV growth has been spearheaded in recent years by markets such as Germany, Japan, Spain and the United States. Pike Research forecasts that the U.S. will become the largest market for small solar energy installations by 2011, surpassing Germany. Momentum is also strong in other European countries, and China and India show significant promise in the long term. www.pikeresearch.com SolFocus receives award from National Renewable Energy Laboratory SolFocus has completed its grant administered by the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL), under the PV Incubator Program. The 18-month, US $2.2 million subcontract was awarded in November 2007 by the Department of Energy to develop reflective opticbased CPV panels that would enable the reliable generation of solar energy at a large scale capable of being costcompetitive with fossil fuels. After a final review at NREL’s Golden, CO, campus, the laboratory determined the SolFocus technology met or exceeded the program’s requirements. The optics developed under this program have been incorporated into the SolFocus 1100S CPV system which has recently transitioned into full scale commercialization, with 11MW of product
being shipped this year and an estimated 100MW of manufacturing capacity in place by the end of 2011. www.solfocus.com. Vitex Systems announces license agreement with major thin-film supplier Vitex Systems Inc., a technology developer, licensor and engineering service provider for thin-film encapsulation and moisture barrier films, has executed a license agreement with a global supplier of specialty materials and related thinfilm services, granting them the rights to develop and manufacture Vitex’s proprietary Barix™ Barrier Film. Licensed fields of use include, but are not limited to, photovoltaic and other large-area thin-film technology based applications. Financial terms were not disclosed. www.vitexsys.com Global flexible and thin-film PV market expected to reach US $58b in 2019, reports IntertechPira study The global flexible and thin-film PV market, despite caution in the overall PV industry, is expected to experience a CAGR of over 35% to 2019, surpassing 32GW according to a major new study by IntertechPira. The Future of Flexible and Thin-Film Photovoltaics provides detailed ten-year volume and value forecasts of the flexible and thin-film PV market by cell type, end-use application and geographic region. It also addresses thin-film production capacity, competition among the candidate technologies as well as financial incentives, such as subsidies, feedin tariffs and purchase power agreements and their effect on the development of this emerging sector of the PV industry. The study predicts that although organic-based PV, with its small base, will likely grow the fastest of the candidate technologies, amorphous silicon is forecast to remain the technology of choice, increasing from approximately 50 to 70% of the market over the next 10 years. www.pirainternational.com. SynergX announces multiple orders for its photovoltaic glass inspection systems SynergX Technologies Inc., a supplier of automated optical inspection technology for the solar panel industry, announced nine orders for its glass-scan inspection systems for photovoltaic glass. The orders come from customers in China and Europe. Glass quality is an important aspect of the manufacturing of both standard crystalline silicon solar panels and thin film solar panels. Poor quality glass
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can disrupt the manufacturing process with in-process breakage and can often be a reason for failure of the solar panel after installation in the field. With twenty year plus warranties that are being provided with solar panels, automated inspection of the glass is the only way to guarantee quality and long term reliability. SynergeX has systems for glass manufacturers, as well as for the factories that cut and temper the glass, and the actual solar panel makers. www.synergx.ca. 4JET reports new orders for thinfilm laser systems Laser system supplier 4JET GmbH of Alsdorf, Germany has received multiple new orders for laser based edge deletion systems. The contracts awarded in the third quarter include robot based and inline systems for manufacturers of CIGS, a-Si and CdTe thin-film solar panels, as well as a MEX system for molybdenum exposure on CIGS solar panels. www.4JET.de Air Products India JV signs two photovoltaic contracts Air Products’ joint venture in India, INOX Air Products Ltd., has recently signed two new contracts with leading Indian PV manufacturers for the company’s SunSource™ Solutions gases and materials to support the burgeoning India PV market. INOX Air Products has signed a long-term gas supply contract to provide bulk and specialty gases to HHV Solar Technologies Pvt. Ltd at its new thin-film PV fab in Bangalore. The contract calls for the supply of hydrogen, nitrogen, oxygen and argon, as well as specialty gases, including silane, methane and dopant mixtures. In addition, INOX Air Products will provide the total gas management at HHV Solar’s research, development and demonstration fab. www.airproducts.com/ sunsource Nanosolar completes panel factory, commences serial production of Nanosolar Utility Panel™ Nanosolar’s new European panel-assembly factory is located in Luckenwalde, Germany, near Berlin. The fully-automated factory processes Nanosolar cells into finished Nanosolar panels using innovative high-throughput manufacturing techniques and tooling developed by Nanosolar and its partners. The panel factory is automated to sustain a production rate of one panel every ten seconds, or an annual capacity of 640 MW when operated 24x7. Nanosolar also announced that serial production in its San Jose, California, cell
production factory commenced earlier this year. www.nanosolar.com Advanced Energy introduces a European version of Solaron 500 KW photovoltaic inverter Advanced Energy IndustriesInc. introduced the Solaron 500E, a European model of its high-efficiency, transformerless, grid-tie PV inverter. Operating at 500 kW, the Solaron 500E enables European commercial and utilityscale PV installations to achieve the lowest levelized cost of energy (LCOE) in the industry by increasing energy harvests and by reducing balance-of-system (BoS) and operating and maintenance (O&M) costs. Rated at a record-setting 97.5 percent CEC-weighted (97.7 percent Europeanweighted) efficiency, the Solaron inverter enables higher energy harvests through its robust controls and patented soft-switching technology. www.aesolaron.com Solar manufacturing to rise 50% in U.S., says GTM Research Despite a recession, manufacturing capacity for solar panels will rise at a rate of 45 percent each year, from 875 megawatts in 2008 to 3,880 megawatts in 2012, according to GTM Research’s recently published report “PV Manufacturing in the United States: Market Outlook, Incentives and Supply Chain Opportunities.” Manufacturing capacity for solar cells will exhibit similarly strong growth, rising 50 percent each year from 785 megawatts in 2008 to 4,001 megawatts by the end of 2012. Overall, the U.S.’s share of global solar manufacturing capacity will increase from just 5 percent in 2008 to 14 percent in 2012. The U.S. will contain a total of 38 PV manufacturing facilities by 2012, compared to 26 at the beginning of 2009. www.gtmresearch.com
Canadian Solar signs technology agreement with Energy Research Center of the Netherlands Canadian Solar Inc. has signed a joint technology development and transfer agreement with Energy Research Center of the Netherlands (ECN) to apply the technology for metal wrap-through (MWT) cells to Canadian Solar’s production lines. MWT cells eliminate the need for front side bus-bars and therefore increase effective surface and the conversion efficiency of a solar cell. A more advanced version of this technology, emitter wrap-through (EWT) structures, can further eliminate the front surface grid and therefore further increase the cell conversion efficiency. Both of these wrapthrough technologies also increase module conversion efficiency by enabling back-side interconnection technology in module production. The specialized module assembly equipment will be developed and manufactured in co-operation with Eurotron, a Netherlands based manufacturer and supplier of handling equipment for module assembly. www. canadian-solar.com, www.ecn.nl First Solar to supply 27 MW of solar modules to Juwi for U.S. utility installations First Solar Inc. has been selected by Colorado-based developer and EPC contractor juwi solar Inc., a subsidiary of juwi Holding AG, to supply solar modules for two U.S. projects. These projects represent new supply orders and do not fall within the existing long-term framework agreement between First Solar and juwi solar GmbH. The projects include a 15 MW (DC) installation for JEA, the eighth largest community-owned electric utility in the U.S. First Solar will also supply
another 12MW (DC) for juwi solar Inc.’s project with American Electric Power in Ohio. The two installations are expected to begin construction in the fourth quarter of 2009 and to be completed before the end of 2010. www.firstsolar.com. Canadian Solar’s PV reliability testing centre joins Intertek’s ‘Satellite Program’ Canadian Solar’s PV Reliability Testing Center is the first PV partner to join Intertek’s “Satellite Program.” This designation by Intertek is another recognition of Canadian Solar’s quality control system and its state-of-art ISO17025 accredited internal laboratory. Intertek developed its Satellite Program, a new Client Data Acceptance Program, in response to the ever-increasing market requirements for product certification. Conducting tests in customers’ own labs, on their own schedule, customers obtain Intertek’s market-leading certifications for their products. Under the Satellite Program, customers can choose the level of service that’s right for their compliance and sales goals. When the testing results meet all certification requirements, Intertek will issue the requested certificate, such as ETL based on UL1703 standards. The practice under the Satellite Program can greatly reduce the testing/certification lead time, thus facilitating the timely introduction of new products into the market place. www.intertek.com, www. canadian-solar.com India’s Tata Group invests in Swiss solar-cell maker India’s diversified Tata Group said on Thursday it has invested in Swiss solar-cell maker Flisom, which is setting up a 5 MW plant for about 25 million euros ($36.8 million). Auto-to-steel conglomorate Tata Group did not say how much it invested in Flisom. Capacity at the Flisom plant, to be set up in Duebendorf, Switzerland, will eventually be increased to 100 megawatts. To know more, visit www.tata.com, www. flisom.ch. [Source: Reuters] Christopher Associates receives multiple photovoltaic module laminator orders Christopher Associates have received orders for several Orient photovoltaic module laminators destined for North American customers. Models ordered included the TDCT-Y semi-automatic systems and the TDCZ-Y fully automatic systems. Christopher first exhibited the Orient product line at Intersolar North
Global Solar Technology – November/December 2009 – 43
America 2009 in July. Orient has delivered over 600 systems worldwide. www. christopherweb.com Applied Materials’ HCT MaxEdge wire saws qualified for production by leading solar wafer manufacture The recently-launched Applied HCT MaxEdge™ wire saw from Applied Materials Inc. is already in volume production at key customers in Europe and Asia for solar PV wafering applications. The MaxEdge system revolutionized wire saw technology with the industry’s first dual-wire system, enabling significantly higher throughput and load capacity than competitive systems, while requiring much less factory floor space and fewer operators for equivalent megawatt output. MaxEdge systems have been qualified for production in as little as four weeks, rapidly meeting customers’ stringent performance and quality specifications. www.appliedmaterials. com Oerlikon Solar customer Tianwei SolarFilms signs one of the largest deals in thin film silicon PV Just three weeks after production officially began, Oerlikon Solar’s Chinese customer Tianwei SolarFilms has signed one of the largest deals in thin film silicon PV history with Thailand Green Energy Co., Ltd. Under the terms of this agreement, Tianwei SolarFilms will provide 70MW of thin film solar panels to rapidly emerging markets across Southeast Asia. At Tianwei SolarFilms, Oerlikon Solar has installed its Amorph High Performance, a technology using a special high-performance front and back contact method in its production lines. A low pressure chemical vapor deposition process is used to generate a transparent conductive oxide layer, which is superior to conventional methods. The light transmission and scattering properties of this layer are very important to achieve the efficiency with which the solar module is able to convert sunlight into electrical energy. www.oerlikon.com/solar Vitex Systems expands development capability Vitex SystemsInc. has expanded its leading edge thin-film barrier capability with the qualification of its new second-generation deposition equipment. The new equipment will be located in Vitex’s facility in San Jose and will allow the company to further enhance its moisture barrier film technology as well as service its customers. In conjunction with its internal expansion efforts, Vitex has also elected to join the
Flexible Display Center located at Arizona State University (ASU) and to donate its previous generation tool to the Center. The Flexible Display Center at ASU, which was established by the U.S. Army in February 2004, boasts collaborations with university, government and industry partners, both national and international. www.vitexsys.com, www.battelle.org JPSA ships PV-5000 thin film laser scribing system J. P. Sercel Associates Inc. has shipped the first of multiple PV-5000 thin film photovoltaic laser scribing systems for the solar industry to a U.S. customer. The PV-5000 is a high volume, high accuracy, robust production system for scribing new thin film on glass solar panels. The system uses advanced laser scribing technology to rapidly and accurately produce fine scribed lines with >30MOhm isolation. www. jpsalaser.com Spire honored with the SOLAR Industry Award 2009 Spire Corporation won the SOLAR PV Management Magazine’s Turnkey Company of the Year Award. The SOLAR Industry Awards have been created to recognize the whole value chain and those people, products, and services that will develop innovative manufacturing and product approaches that have the potential to change the way we live. Spire Solar was chosen after a fourteen-week campaign, voted on by industry professionals, and presented by the magazine’s editor-in-chief, Mr. David Ridsdale. www.spiresolar.com Oerlikon Solar wins award for deposition system Oerlikon Solar has been named winner of the 2009 Solar Industry Award, presented at the EU PVSEC 2009 Conference in Hamburg. The jury selected Oerlikon Solar’s TCO 1200 deposition system as winner of the “Thin Film Innovation Award.” The Oerlikon Solar TCO 1200 is a fully automated, high volume, low pressure chemical vapour deposition (LPCVD) system for the deposition of a novel and adjustable transparent conductive oxide (TCO) film. The TCO 1200 process technology allows adjustment of film morphology and conductivity to match ideal parameters for the PV absorber stack while utilizing an innovative zinc oxide film composition. The zinc oxide composition offers superior light trapping compared to prior TCO solutions. www.oerlikon.com/solar
44 – Global Solar Technology – November/December 2009
Solel awarded US $2.6 million grant from Spanish Government for solar manufacturing facility Solel Solar Systems Ltd. has received a €1.8 million ($2.6 million) grant from the Ministry of Innovation, Science and Enterprise of the Andalusian Region of Spain to be used for the construction and development of a facility to build solar fields components. The facility, in La Carolina, Spain, will be Solel’s first manufacturing plant in Spain, and will include lines for the production of parabolic reflectors, metal supports for solar collectors, and other essential components used for conversion of sunlight to clean electricity. The construction of the plant in La Carolina is expected to be completed in 2012; however, part of the manufacturing lines will be operational already this year. Solel expects to employ in the coming year 70 workers in the new facility, and by 2012, with the completion of the facility, 300 workers will be employed by Solel in La Carolina. www.solel.com Evergreen Solar appoints Henry Ng as general manager—Asian operations Evergreen SolarInc. appointed Henry Ng to the position of general manager—Asian operations. Prior to joining Evergreen Solar, Mr. Ng was general manager of the Suntech Power Holding Co., Ltd. factory in Wuxi, a position he held since July 2007. www.evergreensolar.com Ascent Solar signs multi-year supply agreement with TurtleEnergy Ascent Solar TechnologiesInc. signed a multi-year direct supply agreement with TurtleEnergy LLC, a premium photovoltaic systems integrator headquartered in Linden, New Jersey, where Ascent Solar will deliver up to 67 MW of its high efficiency flexible CIGS photovoltaic modules over five years. Ascent Solar is scheduled to begin shipping products to TurtleEnergy from its Thornton, Colorado, manufacturing plant early next year. www.turtleenergy.com 3S Industries & San-Du Solar Energy build first turnkey module line in Malaysia San-Du Solar Energy, a recently established Malaysian company, is setting up a module manufacturing facility in Malaysia with the strong support of the 3S group. At the EU PVSEC in Hamburg, San-Du Solar Energy and the 3S Group signed a contract for a 25 MW turnkey solution for the first phase
of production. 3S’s comprehensive package includes equipment, in-depth know-how transfer and service. San-Du Solar Energy and 3S have agreed on an aggressive schedule to ramp-up the module line in early 2010 in order to cope with increasing customer demand for BIPV and standard modules in local markets. www.3-s.ch Markets for nanocrystalline silicon devices will reach US $2.1 Billion by 2016 Industry analyst company NanoMarkets continues its coverage of markets for nanocrystalline silicon and printed silicon devices with a new report, “Opportunities for Nanosilicon: 2009 to 2016,” which provides an eight-year forecast of nanocrystalline silicon devices and subsystems used for photovoltaics, memories, display backplanes and RFID devices, as well as other smaller applications. According to the report, photovoltaics will be the largest segment of the nanosilicon market with revenues reaching $1.5 billion in 2016. The report notes that although nanosilicon PV technology is in its infancy, it could solve some of the toughest problems currently facing the thin-film/flexible PV business. Nanosilicon PV requires far less complex and expensive encapsulation than CIGS or organic PV, while at the same time promising higher conversion efficiencies than amorphous silicon PV. www. nanomarkets.net Canadian Solar moves headquarters to Kitchener, Ontario Canadian Solar Inc., opened its new global headquarters in Kitchener, ON, at 650 Riverbend Dr. The new headquarters will be the hub of testimony, education and guidance on a wide range of turnkey solar solutions and opportunities. www.canadiansolar.com Energy Focus Inc. awarded US $3.1 million to develop high efficiency solar module with DARPA Consortium Energy Focus Inc. entered into a $3.1M, two-year contract with the DuPontUniversity of Delaware Very High Efficiency Solar Cell (VHESC) Consortium as part of a Defense Advanced Research Projects Agency (DARPA)-funded effort to deliver advanced solar research to enable high efficiency, low cost photovoltaics. DARPA recently began the second twoyear phase of a four-year program with the VHESC Consortium to raise the system power efficiency of a new class of
solar modules to 40 percent and deliver manufacturable engineering prototype modules. The modules under development by the VHESC team use a novel optical “spectrum splitting” system that directs light from the sun into different paths corresponding to the color of the light, and concentrates the light onto photovoltaic cells that cover different segments of the solar spectrum. DARPA is developing the VHESC solar module technology for compact renewable energy to power both permanent and mobile bases, as well as to reduce the considerable logistical burden of supplying energy (e.g., batteries and fuel) to the U.S. military in the field. www. energyfocusinc.com Three German technology companies enter wafer partnership Three well-known German companies— PVA TePla AG, the Arnold Group, and Gebr. Schmid GmbH + Co.—entered into a partnership in the production of solar wafers. PVA TePla AG manufactures crystallisation equipment, the Arnold Group is a technology leader in grinding processes and in the automation of Si bricks, and Gebr. Schmid GmbH + Co. manufactures photovoltaic production equipment . Together the firms are aiming for technology and cost leadership in wafer processing for the photovoltaic industry. The companies plan to establish a communal technology centre in Germany. In the next few weeks the location for this centre will be chosen and an announcement made as to which other partners are to join the consortium. The start is planned for the beginning of 2010, according to information by the company spokespersons. Applied Materials begins shipments of world’s largest, fastest, roll-toroll vacuum coating systems Applied Materials Inc. has begun shipping multiple Applied Topmet™ 4450 systems, the world’s largest and fastest, roll-to-roll thin film metal deposition machine, to a customer in Europe. This latest model of Applied’s Topmet 4450 product line deposits ultra-thin aluminum films on 4.5 m (15 feet) wide rolls of substrate material at a remarkable 20 meters per second (45 miles per hour) to provide a barrier against oxygen, moisture and ultra-violet radiation for flexible packaging applications. New technology advances in the system produce state-of-the-art film quality while doubling the coated area output to drive down coated film production cost by more than 20%. www.appliedmaterials.com
New solar AC micro-inverter company launched Island Technology launched its wholly owned, Direct Grid Technologies, LLC. The new company will manufacture leading-edge solar microinverters for residential and commercial PV applications. The main thrust of Direct Grid is an innovative, patent pending, closed loop MOSFET planar microinverter design made specifically for thin film type PV modules. The cost effective solution significantly increases microinverter reliability and efficiency. www.directgrid.com Fraunhofer IKTS purchases Optomec aerosol jet solar lab system for front side metallization of solar Optomec announced today that Fraunhofer IKTS (Institute for Ceramic Technologies and Systems) has selected the Aerosol Jet Solar Lab system to be part of their Energy Systems Department. The Aerosol Jet system, which will be installed at the IKTS facility in Dresden, Germany, will be primarily used to develop front side collector line printing solutions to increase solar cell efficiencies. IKTS conducts development work within the framework of R&D projects with its industrial customers spanning the entire value chain, extending through to prototype production. www. optomec.com Mitsubishi Electric making highoutput solar panels for major overseas markets Mitsubishi Electric Corporation announced today the launch of ten new models of PV modules—five for the European market and five for North America and Asia. The new lineup comprises modules with outputs of 210, 220, 225, 230 and 235 watts. The new high-output modules use lead-free solder and incorporate PV cells with four bus bars. Using the new cells in combination with an increased module size achieves a power output of up to 235 watts per module. Larger output means that fewer modules are needed to build a system, helping to reduce total system cost. www. mitsubishielectricsolar.com Solar Applied Materials takes license of RNT’s NanoBond® process technology Solar Applied Materials Technology Corp (Solartech) of Tainan, Taiwan, a supplier of manufacturing, refining and marketing of precious metals, specialty chemicals, and sputtering targets, has entered into a license agreement for the use of RNT
Global Solar Technology – November/December 2009 – 45
NanoTechnologies Inc.’s NanoFoil® and NanoBond® technologies. Solartech has capitalized its facility to bond sputter targets using RNT’s patented room temperature bonding technique. NanoBond® is used to bond sputter targets with the additional benefits of minimizing the CTE mismatch of target and backing plate materials, improving the overall performance of target assemblies in use, and providing a more environmentally friendly process solution. Solartech has completed RNT’s Level 1 Certification Training at RNT’s facility and is expected to offer NanoBond® services to its customers beginning in Q4 2009. www. rntfoil.com, www.solartech.com.tw JA Solar developing next generation solar products using silicon ink technology from Innovalight JA Solar Holdings Co., Ltd. (JASO) is working to commercialize a new generation of high-performance solar products using silicon ink technology from Innovalight Inc. Innovalight Inc. , a privately held firm based in Sunnyvale, California, recently announced that it has demonstrated a record 18 percent conversion efficiency using silicon ink technology and conventional silicon wafers. Results were independently certified by two of the world’s recognized solar cell testing centers, the U.S. Department of Energy’s National Renewable Energy Laboratory (NREL), and The Fraunhofer Institute for Solar Energy Systems (ISE) in Germany. JA Solar is currently developing silicon ink-based high efficiency solar cells at its R&D pilot line in Yangzhou, China with plans for initial commercialization in 2010. www. jasolar.com, www.innovalight.com XsunX and Intevac team up to develop breakthrough thin-film photovoltaic manufacturing technology XsunX Inc. and Intevac Inc. are working under a Joint Business Agreement to collaborate in the development of techniques and equipment for the production of commercially marketable processes and equipment for the manufacture of CIGS (copper indium gallium selenide) thin-film solar cells. Through the successful combination of cross-industry specialties, XsunX and Intevac plan to develop a new breed of TFPV manufacturing techniques to produce thin-film solar cells. By teaming up, the companies plan to effectively combine Intevac’s unparalleled expertise and years of technological improvements
developed for the sophisticated HDD manufacturing industry with XsunX’s experience in the TFPV industry, which includes senior staff with years of commercially successful CIGSrelated technology development. The two companies are adapting high-rate production tools from the disk drive industry with process knowledge from the CIGS and thin-film industry. This unique and novel approach focuses on maintaining a relatively small deposition area; initially about five-inch squares similar in size to silicon solar wafers, which the companies believe reduces a significant challenge that has faced the CIGS industry in the past: maintaining cell performance while scaling commercial production. www. xsunx.com, www.intevac.com Total, GDF SUEZ, and Photovoltech join IMEC’s silicon solar cell research program The two major energy companies, Total and GDF SUEZ, and their common solar cells manufacturing subsidiary Photovoltech, join the IMEC industrial affiliation program (IIAP) on next generations of crystalline silicon solar cells. The multi-partner R&D program concentrates on sharply reducing the silicon use, whilst at the same time increasing the efficiency of solar cells. This will substantially lower the cost for solar energy. With its IIAP, IMEC sets up a research ecosystem with the aim to create innovative processes to fabricate the next generations of silicon solar cells. GDF SUEZ, Total and Photovoltech will dedicate researchers to this program. www. imec.be Natcore initiates sponsored research program with Rice University Natcore Technology Inc. has signed a sponsored research agreement with Rice University to develop thin films incorporating silicon quantum dots. These quantum dots are an important step in the development of tandem solar cells that could double the power output of current silicon solar cell technology. The sponsored research agreement will be directed by Professor Andrew R. Barron as principal investigator and employ the resources of the Barron Research Group at Rice. The initial term and estimated funding of the agreement is one year and US $100,000; both the term and the funding can be extended under mutual agreement. www. Natcoresolar.com
46 – Global Solar Technology – November/December 2009
QuantaSol adopts dilute nitrides to boost absorption and solar efficiency QuantaSol Ltd, an independent designer and manufacturer of strain-balanced quantum-well solar cells has exclusively licensed advanced materials growth technology from the University of Houston to make its manufacturing process simpler and cheaper, while further improving solar cell efficiency. QuantaSol combines nanostructures, ‘quantum wells’, of two or more different alloys, in order to obtain synthetic crystals. The crystalline structure can be tuned during manufacture to overcome the absorption problems associated with current concentrator photo-voltaic (CPV) cell designs. The quantum well effect also greatly enhances the photovoltaic conversion efficiency, as already proven by its recent world record efficiency single junction device. Ultimately QuantaSol will produce highly efficient triple junction CPV devices in 2010. The use of dilute nitrides will allow QuantaSol to reduce the number of quantum well layers it needs to introduce into each junction, while maintaining or increasing solar efficiency. This further reduces the thickness and manufacturing cost of its production devices. www. quantasol.com, www.cam.uh.edu, www.uh.edu New NanoMarkets report identifies the key opportunities for buildingintegrated photovoltaics According to NanoMarkets’ new report, “Building-Integrated Photovoltaics Markets 2009 and Beyond,” revenues from building-integrated PV will grow from about US $1.8 billion this year, to reach over $8.7 billion in 2016. While the PV market, and specifically the BIPV market, will be impacted by the current recession, the combination of policy incentives and trends in architectural style produces a need for aesthetic integration of PV cells into the buildings that use them. NanoMarkets also expects to see a shift in the type of PV materials used in building-integrated products. While crystalline silicon (c-Si) currently makes up about 75 percent of the market in volume terms, by 2016 this value will drop to close to 33 percent as the thin-film PV technologies penetrate the market. By 2016, NanoMarkets projects that thin-film silicon will represent 35 percent of the BIPV market while CIGS will have 17 percent share. www.nanomarkets.net
The key to the solar factory
Events Calendar 9-11 November 2009 Solarcon India Hyderabad, India www.solarconindia.org
3-5 March 2010 PV Expo 2010 Tokyo, Japan www.pvexpo.jp
9-13 November 2009 19th International Photovoltaic Science and Engineering Conference and Exhibition Jeju, South Korea www.pvsec19.kr
3-5 March 2010 25th Photovoltaic Symposium Bad Staffelstein, Germany www.otti.de
7-8 December 2009 Solar Conference 2009 (CanSIA) Toronto, Canada www.cansia.ca 2-4 December 2009 Semicon Japan 2009 Chiba, Japan www.semiconjapan.org 16-20 February 2010 Solar Energy 2010 Berlin, Germany www.messen-profair.de
16-18 March 2010 Semicon China 2010 Shanghai, China www.semi.org 30 March-1 April 2010 2010 5th AsiaSolar PV Industry Exhibition & Forum Shanghai, China www.asiasolarexpo.com 27 April 2010 PHOTONâ€™s 8th Solar Silicon Conference Stuttgart, Germany www.photon-expo.com
17-22 May 2010 Solar 2010 Phoenix, United States www.ases.org 24-26 May 2010 PV America Tampa, United States events.jspargo.com 9-11 June 2010 Intersolar Munich, Germany www.intersolar.de
invest future in your
First Solar Manufacturing, Frankfurt, Germany (top)—featured in Global Solar Technology issue 2.2, Mar/Apr 2009.
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News for Solar Manufacturing Industry
News for Solar Manufacturing Industry
Volume 2 Number 1 Jan/Feb 2009
Paul Davis Interview Inside
MATERIALS AND THE GROWTH OF PV TECHNOLOGY COMBATING THE IMPACT OF CONTAMINATION IN SOLAR CELL PRODUCTION
FLEXIBLE SILVER PASTE ENABLES THIN-FILM PHOTOVOLTAIC FLEX SOLAR CELLS
CONVERTING CONSIDERATIONS FOR FLEXIBLE MATERIALS
INDUSTRY NEWS INTERNATIONAL DIARY
ULTRASONIC ATOMIZATION FOR UNIFORM DISPENSING AND COATING OF
TRANSFER PRINTING: AN EMERGING TECHNOLOGY FOR MASSIVELY PARALLEL ASSEMBLY OF MICRODEVICES
Bjorn Dahle Interview Inside NEW PRODUCTS INDUSTRY NEWS INTERNATIONAL DIARY
NANOPARTICLES SOLAR: IT’S ABOUT TIME
News for the Solar Manufacturing Industry
News for the Solar Manufacturing Industry
Volume 2 Number 3 May/June 2009
Volume 2 Number 4 July/August 2009
Steamer vS. torch in Pv manufacturing—a coSt of ownerShiP comPariSon
comBing in the energY
Dr. Madhusudan V. Atre Interview Inside NEW PRODUCTS INDUSTRY NEWS INTERNATIONAL DIARY
The imporTance of cpk Debugging anD verifying microinverTers for phoTovolTaic insTallaTions lasers, for more efficienT solar cells
News for Solar Manufacturing Industry
Volume 2 Number 2 March/April 2009
SOLAR INTEGRATION TAKES A PAGE FROM THE SEMI WAFER CSP PLAYBOOK
LASER SCRIBING TOOLS EDGE IN FRONT
INDUSTRY NEWS INTERNATIONAL DIARY
PerSPectiveS on SemiconDuctor ecoSYStem—the SoLar route
Global Solar Technology Volume 2 Number 2
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CONFORMAL COATING IMPROVES THE RELIABILITY AND LIFE OF SOLAR INVERTERS
Rajinder Kumar Interview Inside NEW PRODUCTS INDUSTRY NEWS INTERNATIONAL DIARY
KIC ON BOARD
50 – Global Solar Technology – November/December 2009
Published on Nov 19, 2009
Published on Nov 19, 2009
Silicon solar cell efficiency & thermal process optimization in the metallization process; Making I‑V and C‑V measurements on solar/photovol...