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GROUP 4C

PROBLEM REPORT

ASCAS

CITY UNIVERSITY OF HONG KONG 2012


CONTENT

ASPECT & PRINCIPLE & ASSESSMENT

RENEWABLE ENERGY

SUSTAINABLE TECHNOLOGY

SUSTAINABLE MATERIALS

CASE STUDY


GROUP 4C

PROBLEM REPORT

GROUP MEMBERS:

ASCAS

CITY UNIVERSITY OF HONG KONG 2012


ASPECT & PRINCIPLE & ASSESSMENT Definition of ASPECT and PRINCIPLES •Aspect means the major area that we concern when we design or plan •Principles are the solution based on the 3 aspects commonly defined and always stick to it when designing or planning

ASPECTS Social finding ways to increase prosperity and improve the quality of life while reducing overall pollution and waste Economical meeting our own needs and aspirations without doing damage to the prospects of future generations Environmental reducing the environmental burden we put on our neighbors and helping to preserve common resources.

Environmentally viable sustainable socially desirable

ecomonically feasible

"development that meets the needs of the present without compromising the ability of future generations to meet their own needs.“

PRINCIPLES

Conserve: This is the starting principle because it is in contrast to the major problem that forces us to address sustainability in the first place: overconsumption. This should force us to minimize energy consumption and to use durable materials that have long lifetimes and require low maintenance. Reuse: Items are simply used intact with minimal reprocessing. A significant business exists dealing in architectural items such as windows, doors, and brick, which are being reused in new construction and renovation, but it is necessary to promote this practice. Renew/Recycle: Prioritize the use of resources that are renewable or recyclable such as wood or scrap steel. Those common construction materials can be supplied from certified sustainable forests or recycled from cars. Protection of nature: Inevitably our actions in creating the built environment will impact the natural environment and its ecological systems. It is time not just to sustain but to restore where possible the original natural conditions. Non-toxicity: This addresses toxic substances produced by industries, which have invaded the environment and had inevitable negative effects on humans. Clearly toxic materials must be handled with care and eliminated to the greatest extent possible. The outcome of this principle in a practical sense is the elimination of toxic materials in the indoor and exterior built environment. Quality: The notion of quality (longevity, functional durability, flexibility) includes all aspects of sustainable construction and is part of all of these.

Principles have to be sufficiently broad in scope to encompass all construction problems of a sustainable building and flexible enough to adapt to evolution of technology. Also they have to be easy to comprehend and use.


GROUP 4C

PROBLEM REPORT

ASCAS

CITY UNIVERSITY OF HONG KONG 2012

ASSESSMENT METHODS

Professional Green Building Council Green Building (PGBC) Green Building Award is a new industry award organized by the Professional Green Building Council (PGBC), which is jointly founded by the Hong Kong Institute of Architects (HKIA), the Hong Kong Institution of Engineers (HKIE), the Hong Kong Institute of Landscape Architects (HKILA), Hong Kong Institute of Planners (HKIP), and the Hong Kong Institute of Surveyors (HKIS). With the launch of the GBA, PGBC aims to provide recognition to buildings and research projects with outstanding features and contributions in sustainability and the environment and also to encourage the industry towards further adoption of sustainable planning, design, construction and maintenance of buildings. Building Environmental Assessment Method (HK-BEAM) BEAM provides building users with a single performance label that demonstrates the overall quality of a building, either a new or refurbished building or one that is already in use. A certified BEAM building is safer, healthier, more comfortable, more functional and more efficient than a similar building that does not achieve the level of performance prescribed in BEAM. BEAM is: • the leading initiative in Hong Kong to assess, improve, certify and label the performance of buildings; • a set of comprehensive standard procedures covering all building types, including mixed use complexes; • a means by which to benchmark and improve performance; • a voluntary scheme developed in partnership with, and adopted by the industry, at a level that makes it one of the leading schemes in the world; and • a driver for and means by which to sustain healthy, efficient, and environment friendly working or living environment. Comprehensive Assessment Method for Built Environment Efficiency (CASBEE) Under CASBEE, these two factors re defined below as Q and L. the main assessment categories, and evaluated separately. •Q (Quality): Built Environment Quality •Evaluates “improvement in living amenity for the building users, within the hypothetical enclosed space (the private property).” •L (Load): Built Environment Load •Evaluates “negative aspects of environmental impact which go beyond the hypothetical enclosed space to the outside (the public property).” Therefore the assessment categories contained within these two fields had to be examined and reorganized. Q is further divided into three items for assessment: Q1 Indoor environment, Q2 Quality of services and Q3 Outdoor environment on site. Similarly, L is divided into L1 Energy, L2 Resources and Materials and L3 Off-site Environment. Environment Labeling Using Built Environment Efficiency (BEE) BEE, is the core concept of CASBEE. BEE, as used here, is an indicator calculated from Q as the numerator and L as the denominator. Leadership in Energy and Environmental Design (LEED) LEED is a voluntary, consensus-based, market¬-driven program that provides third-party verification of green buildings. From individual buildings and homes, to entire neighborhoods and communities, LEED is transforming the way built environments are designed, constructed, and operated. Comprehensive and flexible, LEED addresses the entire lifecycle of a building. For commercial buildings and neighborhoods, to earn LEED certification, a project must satisfy all LEED prerequisites and earn a minimum 40 points on a 110-point LEED rating system scale. Homes must earn a minimum of 45 points on a 136-point scale.


RENEWABLE ENERGY

WIND Renewable energy is energy that comes from natural resources such as sunlight, wind, rain, tides, waves and geothermal heat, which are renewable because they are naturally replenished at a constant rate.

evwind.es

WIND ENERGY

SOLAR ENERGY BIOMASS

Wind energy is generated by kinetic energy of wind. When air movement rotate the turbine rotor, it can produce electricity. There are mainly two types which are large wind turbines and small wind turbines. For large wind turbines, the most cost-effective size range was 600-750 kW with rotor diameter in the range of 40-47m. They are usually installed in arrays in wind farms in windy locations. For small wind turbine, it is about 100W to 10kW with rotor swept area smaller than 200 sq. m, or around 17 m in diameter. They often used in remote locations and sometimes in conjunction with PV panelsprovide off-grid power. Solar energy, radiant light and heat from the sun, has been harnessed by humans since ancient times using a range of ever-evolving technologies. Solar energy technologies include solar heating, solar photovoltaics, solar thermal electricity and solar architecture, which can make considerable contributions to solving some of the most urgent problems the world now faces. Biomass is plant matter used to generate electricity with steam turbines & gasifiers or produce heat, usually by direct combustion. Examples include forest residues (such as dead trees, branches and tree stumps), yard clippings, wood chips and even municipal solid waste. In the second sense, biomass includes plant or animal matter that can be converted into fibers or other industrial chemicals, including biofuels. Industrial biomass can be grown from numerous types of plants, including miscanthus, switchgrass, hemp, corn, poplar, willow, sorghum, sugarcane, bamboo,and a variety of tree species, ranging from eucalyptus to oil pal.


GROUP 4C

PROBLEM REPORT

ASCAS

CITY UNIVERSITY OF HONG KONG 2012

BIOMASS

SUN

yournucara.wordpress.com

ADVANTAGES

DISADVANTAGES

•Wind energy is friendly to the surrounding environment, as no fossil fuels are burnt to generate electricity •Wind turbines take up less space Windmills only have to occupy a few square meters for the base, this allows the land around the turbine to be used for many purposes •wind is free

•Wind turbines generally produce allot less electricity than the average fossil fuelled power station •Wind turbine construction can be very expensive •The noise pollution from commercial wind turbines is sometimes similar to a small jet engine.

•Natural , clean and renewable •No harmful gases is generated •Can generate energy everywhere on the earth •Do not require energy to run the energy-producing process

•High installation cost •Performance can by affected by location •Only useful in daytime, and bright shinning light

•Reuse so organic waste . E.g forest residue •Can create several products - electricity/ heat/biogas/biofuel •Lots of different technology can be used to generate energy •Material used for biomass is in constant supply

•Only large scale biomass plants is efficient enough to generate a net gain of energy •Quite a expensive energy source, as it includes both planting process and conversion process •Produce some green house gas


SUSTAINANLE TECHNOLOGY SUN

Shading devices Shading device can be provided by natural landscaping, such as trees and hills. Also, it can be provided by building elements, such as overhangs, awings, fins and trellises. It can be identified as two main types: horizontal and vertical shading devices. The advantages of using shading devices are that if can reduce the building peak cooling load and corresponding energy consumption and enhance daylight utilization in buildings, and avoid glare by reducing contrast ratios of building interior. However, for the vertical shading device, it may restrict the views of the building. Low-e reflective glazing Low emissivity glass has a special metal coating on one side - either Pyro-lytic (hard coat) or sputtered (soft coat). The microscopically thin and almost invisible coating acts as a filter that it blocks the long wave radiation (such as infrared heat) and passes the short wave radiation (such as UV and visible light) through the exterior to the interior. The pros of using low-e reflective glazing are that it can reduce the thermal gain and loss of interior, thus. It can reduce the demand of air-conditioning, so reduce the emission of carbon dioxide. Also, it can reduce the demand of artificial lighting since the natural sunlight can pass through the glazing. However, the low-e reflective glass is more expensive than the normal glass. Moreover, the reflective glazing may produce glare to the next building. Insulated glazing Insulated glass consists of 2 or more panes of glass which are bonded together with plastic material (e.g. PVB). The space between the panes acts as a thermal buffer and can be filled with dehydrated air, inert gas or in vacuum. Since heat transport through a laminated glass unit by convection, radiation, conduction, filled with gas between the panes would be insulation layer which can reduce the heat gain and heat loss from exterior to interior of the building. The advantages of using insulated glazing are that is can reduce the heat gain and loss of the building, and it can also enhance the noise insulation. However, it is more expansive than the normal glazing and the maintenance cost of insulating glass is high.

WIND

Openable windows There are two main methods which are cross ventilation and stack effect to apply for openable windows to provide natural ventilation for buildings. For cross ventilation, it relies on wind to force cool exterior air into the building through an inlet and to force warm interior air out of the building through an outlet. Adding hedges can maximise the wind flow into the room. Windcatcher Windcatcher often used in combination with courtyards and domes as overall ventilation. It is usually a tall, capped tower with one face open at the top (facing prevailing wind). Opening faces the wind that can bring air flow into the tower and then maintain ventilation to cool the interior of the building. However, it can only apply for low-rise building. Louvers Louver is a framed opening, as in a wall, door, or window, fitted with fixed or movable horizontal slats. It admits natural ventilation and also lighting into the interior and sheds the rain. The louver windows can open and shut. Therefore, sunshine control and privacy protection are possible so to improve the energy saving effect. The advantages of using louvers are that natural ventilation can be provided so that it is good for human health and reduces the demand of using air-conditioning.


GROUP 4C

PROBLEM REPORT

ASCAS

CITY UNIVERSITY OF HONG KONG 2012

ADVANTAGES

DISADVANTAGES

•reduce heat gain of building •decorative features of building •automatic devices can further enhance the function more precisely.

•some devices may block the view partially •some devices may require extra space to fix the shading. •regular maintainence may be required

•provide natural sunlight without heat

•increase the cost of the building

•provide natural sunlight without heat

•increase the cost of the building

DIAGRAM

Source: Intelligent Glass Facades

•reducing the demand of using air-conditioning and energy saving. •stack effect can enhance the flow of wind

•it may bring humidity from interior of the building.

•Reduce the demand of air-conditioning •Provide fresh air to the interior

•Only use in low-rise building

•provide natural ventilation into the room

•may be too humid for office that may damage the documents

With hedges can maximize the wind flow into the room

Source:http://htmlimg3.scribdassets.com/7r4cikgz0g193q2i/ images/137-a3583b6673.jpg

Source: http://archlouvers.com/Images/E4JS3DRain.jpg


SUSTAINANLE TECHNOLOGY WATER

GREENARY

Grey water recycling system Since we are now concerning about the water conservation, grey water recycling system would be applied for buildings. Grey water was typically defined as wastewater from kitchens, baths, showers, basins and laundry. This System is used for collection, filtration and disinfection of waste water and then mainly applied in toilet flushing, firefighting, water cooling and irrigation. Collected grey water subjected to biological and micro-filtration treatment to disinfect and adjusted in acidity. The water would be stored in grey water tanks. It can reduce the waste water pollution in environment. However, there is a potential for spreading disease through human contact if not properly handled or treated. Green roof A green roof or living roof is a roof of a building that is partially or completely covered with vegetation and a growing medium, planted over a waterproofing membrane. It may also include additional layers such as a root barrier and drainage and irrigation systems. Green roofs serve several purposes for a building, such as absorbing rainwater, providing insulation, creating a habitat for wildlife, and helping to lower urban air temperatures and mitigate the heat island effect. There are two types of green roofs: intensive roofs, which are thicker and can support a wider variety of plants but are heavier and require more maintenance, and extensive roofs, which are covered in a light layer of vegetation and are lighter than an intensive green roof. Green wall A green wall is a wall, either free-standing or part of a building, that is partially or completely covered with vegetation and, in some cases, soil or an inorganic growing medium. Grenn wall can be constructed in different medium. The 3 most common mudium includes: loose medium, mat medium and strcutural medium, which of them will required differnt environment , plant spieces and period for maintainence.

BUILDING SERVICES

Building automation It is a management system of building functionality provided by the control system of a building. A building automation system (BAS) is an example of a distributed control system. The control system is a computerized, intelligent network of electronic devices designed to monitor and control the mechanical, electronics, and lighting systems in a building. BAS core functionality keeps the building climate within a specified range, provides lighting based on an occupancy schedule, and monitors system performance and device failures and provides email and/or text notifications to building engineering/maintenance staff. The BAS functionality reduces building energy and maintenance costs when compared to a non-controlled building. A building controlled by a BAS is often referred to as an intelligent building A light-emitting diode (LED) LEDs are used as indicator lamps in many devices and are increasingly used for other lighting. LEDs present many advantages over incandescent light sources including lower energy consumption, longer lifetime, improved physical robustness, smaller size, and faster switching. LEDs powerful enough for room lighting are relatively expensive and require more precise current and heat management than compact fluorescent lamp sources of comparable output.


GROUP 4C

PROBLEM REPORT

ADVANTAGES

ASCAS

CITY UNIVERSITY OF HONG KONG 2012

DIAGRAM

DISADVANTAGES

•recycled water is crystal-clear, free from bacteria, odourless •can reduce the wastewater pollution in environment •Low cost and low maintenance

•Need to provide a space for the grey water tank

•Visually comfort to people •Act as dust and noise filter •Absorb solar radiation •Purify water in the grey water reuse process •Function for urban gardening and argricuture

•Regular maintenance is required for extensive green roofs •Increasing the loading of roof

http://www.architecturenewsplus.com/projects/706

•Mitigating urban heat island effect •Reducing heat gain from roof •Prolong the life of roofing materials •Reducing sound transmission •Controlling storm water runoff

•Regular maintenance is required for extensive green roofs •Increasing the loading of roof

•Greater precise and easy to control the •High cost in installing , designenvironmental parameter ing and investing the system •Can turn on/ off the device automati- •Regular maintenance is required cally to prevent wastage of energy •power / energy saving •less manpower usage •better security •better convenience

dallasgreenbuildingalliance.com

http://www.mge.com/business/saving/madison/PA_36.html

•High energy efficiency •Easily dimmed •Very little heat output •Long lifespan •Short on-off time •Able to emit light of an intended •color without using filters

•High initial cost •Performance depends on the ambient temperature •Voltage sensitivity requires regulated electric supply

obviousmag.org


SUSTAINABLE MATERIAL What are the building materials?

Green building materials are composed of renewable, rather than nonrenewable resources. Green materials are environmentally responsible because impacts are considered over the life of the product (Spiegel and Meadows, 1999). Sustainable building materials have environmental and health merits which traditional materials have typically not considered. The production and use of these materials means less energy consumption, less natural resource depletion and pollution, and are generally less toxic for both the planet and its occupants.

Embodied Energy

Embodied Energy is the sum of all the energy required to produce goods or services, considered as if that energy was incorporated or 'embodied' in the product itself. Carbon Footprint It has been defined as "the total set of greenhouse gas (GHG) emissions caused by an organization, event, product or person. Table for the energy used and the emission of carbon dioxide of Materials


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ASCAS

Natural materials are generally lower in embodied energy and toxicity than man-made materials. They require less processing and are less damaging to the environment. Stone Stone is a highly durable, low maintenance building material with high thermal mass. It is versatile, available in many shapes, sizes, colours and textures, and can be used for floors, walls, arches and roofs. Stone blends well with the natural landscape, and can easily be recycled for other building purposes. Lime It absorbs carbon dioxide from the atmosphere and then forms a strong yet permeable coat of limestone. Also, it is resilience, durability, and water resistant. Natural Fibers It undertakes as reinforcing components owing to their fast growth, high mechanical strength, low density, carbon sequestration, biodegradability and low energy consumption. Bamboo is excellent for the environment, due to its ability to form microclimates and its incredible absorption of carbon dioxide. As well as being highly renewable, the embodied energy in bamboo can be reduced to zero. Wood It has low embodied energy, which can slow harmful effects of industrial production. Earth Plaster It is one of the most enjoyable natural materials to work with. When mixed and applied properly, wall covering will be hard, durable, and beautiful. Also, one of advantages of using earth plaster is that the color of the plaster itself can eliminate the need for any paint. This is good for the environment and can reduce construction costs. Table for the comparison of types of coatings

CITY UNIVERSITY OF HONG KONG 2012

Recycling Materials: Key building materials that have potential for recycling. These generally make up the bulk of a building’s fabric. The manufacturing process for all of these materials can easily incorporate waste products. Glass, plastics, and metal It can be reformed through heat. Concrete or brick It can be ground up and used as aggregate in new masonry. Lumber It can be used as dimensional lumber, or chipped for use in composite materials such as strand board. Glass and Glazing Materials Argon Gas Originally, the space was filled with air or flushed with dry nitrogen just prior to sealing. In a sealed glass insulating unit, air currents between the two panes of glazing carry heat to the top of the unit and settle into cold pools at the bottom. Filling the space with a less conductive, more viscous, or slow-moving gas minimizes the convection currents within the space, conduction through the gas is reduced, and the overall transfer of heat between the inside and outside is reduced. Tinted Glass It refers to any glass that has been treated with a material such as a film or coating that reduces the transmission of light through it. Glass can be tinted with various types of coating, which block and/or reflect different amounts and types of light, according to the needs and preferences of the consumer. Tinted glass is also used in commercial buildings to keep the inside cooler, and it has the added benefit of giving the outside of a building a more uniform, aesthetically pleasing appearance. Metal Coating Metal coating is necessary to provide various degrees of protection, ranging from hot-dipped and electroplated process to tough polymers and flame-sprayed ceramics. It aims To block long wave radiation and let in short wave radiation.


CASE STUDY One Peking Location: Tsim Sha Tsui, Hong Kong Client: The Glorious Sun Holdings Limited Architect: Rocco Design Limited Year of Completion: 2003 GFA: 26339 sq. m Storey: 26 Structure: Reinforced Concrete Structure Characteristics: Distinctive form Award: Considerate Contractors Site Award Scheme 2002 HK-BEAM Assessment Rating-Excellent 2003 HKIA Medal of the Year 2003 HKIE Joint Structural Division Special Award 2004 Quality Building Award 2004 HK Energy Efficiency Awards 2006(Commercial Buildings Sub-category) – Bronze Award HK Energy Efficiency Awards 2006(Special Awards) – New Building Award PGBC Green Building Award 2006 (New Building Category) – Merit Award

ASPECT & PRINCIPLE

PGBC This assessment method has criteria only but not score sheet and will not assess it point by point. Some of the key design lead to the award are shown on the picture below:

HK-BEAM This assessment method has criteria only but not score sheet and will not assess it point by point. Some of the key design lead to the award are shown on the picture below: The rating of One Peking by HK-BEAM is Platinum which is the highest level for this assessment method.


GROUP 4C

PROBLEM REPORT

ASCAS

CITY UNIVERSITY OF HONG KONG 2012

Shimizu Co. Headquarters Location: Kyobashi, Tokyo, Japan Client: Shimizu Corporation Architect: Shimizu Corporation Year of Completion: 2012 Total Floor Area: 51,355 sq. m Storey: 22 stories with 3 lower ground floors Structure: Reinforced Concrete Structure with Base Isolation System Characteristics: World’s Least CO2-Emitting Building Award: CASBEE: rank S BEE score 9.7 LEED gold Award

ASPECT & PRINCIPLE CASBEE Major design that account for the credits in CASBEE are shown on the picture below


CASE STUDY

RENEWABLE ENERGY

As the building is surrounded by low-rise buildings and wide streets, the PV panels are installed in external wall with approximately 2000 sq. m to maximize the solar gain and then generate much electricity. There are two types of PV panels. Poly-crystal panels are installed in windows in common areas and thin film panels are installed in office windows. This system can generate about 23.4kW electricity for the building and it is used for powering the building’s daytime lighting needs (LED lighting) and motorize the shading devices automatically.

ONE PEKING CONSTRUCTION ELEMENTS

GLAZING AND GLASS MATERIALS

COMPARISION

Reusable Formwork Systems Steel formwork for flooring construction was employed during construction period to reduce the use of waste timber generation. The benefits of adoption of reusable formwork systems are to reduce the waste timber and save operating cost for the metal formwork could be reused for other projects.

Metal Soft Coat Soft coat Low E, or sputter coating, is applied in multiple layers of optically transparent silver sandwiched between layers of metal oxide in a vacuum chamber. This process provides the highest


GROUP 4C

PROBLEM REPORT

ASCAS

CITY UNIVERSITY OF HONG KONG 2012

Shimizu Co. Headquarters

MUTUAL

CFT Reuse The frame consists of three parts: circular CFT (concrete-filled tube) columns, wide flange steel beams and beam-to-column connections that are made of circular tube with wide flange shape brackets. When we reuse the structural members of the frame, all members must be taken apart easily. For this reason, beams are connected to beam-to-column connection by high-strength bolts and splicing plates, and columns are just set into the tube of beam-to-column connection. The gap between two tubes (CFT column and beam-to-column connection) is filled by high strength mortar. In order to clarify the elastic-plastic characteristics of this frame, he T-shape frame models consisting of CFT column and beam-to-colLOW-E GLASS Between each pane of glass, low-E argon windows contain argon gas. Argon gas is considerably more effective at reflecting heat than regular air. This means that unwanted heat is deterred from entering the building and interior heat is prevented from leaving. Whether in spring, summer, fall or winter, the result is a more stable climate within buildings.

Source: http://www.gammonconstruction.com/en/html/projects/ projectslhttp://www.beamsociety.org.hk/fileLibrary/One%20Peking_GCPL_C1071.pdf

Recycling Facilities During the construction period, designated areas were provided for segregation of inert and non-inert waste for recycling. Metal and timber wastes were collected for reuse and recycling

STRUCTURAL ELEMENTS Reinforced concrete Core (partially steel frame) RC concrete is one of the most sustainable Materials. It is less energy consumption and less natural resource depletion and pollution.


CASE STUDY SUSTAINABLE TECHNOLOGY

ONE PEKING

Air-conditioning system The building is using HVAC system with a central chiller plant which is located at 6/F. It has demonstrable filtration performance and careful placement of exhaust. The air intakes and exhaust points are located on the 6/F in opposing directions so to avoid short-circuiting exhaust into the incoming fresh air supply. The lowest building exhaust is at 4/F and nearly 30m above street level that can prevent to annoy the neighbours and passers-by. The HVAC system include heat wheel and heat pipe combination (heat recover cooling system). Heat wheels are interlocked with the extraction systems for energy saving and heat pipes is used to enhance dehumidification. It can provide a healthier environment because of unfavourable for the growth of bacteria. Besides, it has a smaller chiller plant with lower electricity power consumption which saving the cost. Moreover, it is low maintenance for heat pipes. Greenery The building provides landscape roof and sky court with greenery and it can act as duct filter to improve air quality. Renewable energy – Solar energy A large scale of Building integrated photovoltaic panels are installed at the rooftop and it is facing south direction to gain a larger amount of sunlight to generate much electricity. The PV panels can produce 7.2kW and some energy would be stored in the batteries. It is used to power the sunlight sensors which control the venetian blinds’ blade angles. Triple glazed active wall system The façade of One Peking was done by adopting a triple-glazed active wall system that combining three layers of low-E clear glass with a ventilated cavity to enhance the light transmission but reduce the OTTV(overall thermal transfer value ). It also applies inclined ceiling rise at perimeter zone to strengthen the spatial effect. Outside the windows, aluminum sun-shading fins serve as reflectors bouncing light up onto the angled ceiling to transmit more natural light inside while limiting the entry of direct sunlight at the same time. This can reduce the heat gain of the façade and interior environment. South facade The south elevation features innovative arrangements to reduce solar gain yet allow increased light transmission at the same time. Although standard ceiling heights in the development are 2,800 mm on office floors, inclined ceilings rise as they reach the windows, which gain extra height as a result. Outside the windows, aluminium sunshading fins serve as reflectors bouncing light up onto the angled ceiling to transmit more natural light inside while at the same time limiting the entry of direct sun. At night, these same fins are lit from below as architectural features. The top of south façade also equipped with the solar panels.These BIPV panels are erected at the top of the building, connectedwith the grid electricity. Each panelis a 100x100mm silver color polycrystalline silicon cell and used to absorb the solar energy that is converted into electricity and supply to the building. East & west façade On the east and west side, there are automatic blind system to deal with the low sun angle. Venetian blinds are housed in a 200 mm air gap in the glazing system and are operated by a computerised system. When sunlight sensors detect a need for shade, the blinds automatically descend to cut glare and heat gain in the interiors. Sensors also control the blinds’ blade angles and power for their operation comes from an array of photovoltaic panels located at the rooftop.


GROUP 4C

PROBLEM REPORT

ASCAS

CITY UNIVERSITY OF HONG KONG 2012

Shimizu Co. Headquarters Grey water recycling system The grey water tank of grey water recycling system was installed at R/F. The system is mainly used as toilet flushing in each floor to reuse the waste water. Also, it can reduce the waste water pollution in the environment. Air-conditioning system The building is using radiative air-conditioning system which directly control of perceived temperature through radiant heat. The air exhaust discharge point is located at the roof so it can avoid to annoy the neighbours. This system consists of desiccant dehumidifier to control the humidity of interior. Also, it provides personal floor vents to provide ventilation for each staff. It can make the environment more comfortable and free of unpleasant drafts. Furthermore, the air conditioning units are unnecessary so to reduce the energy consumption and exhaust air. Greenery The building provides green roof and greenery at ground level. It can reduce the heat island effect and heat gain from roof. Hence, it can reduce the demand of using air-conditioning. Hybrid exterior system The perimeter frame is made of pre-stressed concrete slabs, each measuring 3.2 meters wide, 4.2 meters high, 0.9 meters thick and weighing 14 tons. These deeply embossed pre-stressed concrete components cast long shadows over the window glass, reducing the exterior heat load by 50%. With roughly 2,000 square meters of solar panels installed in these openings, the building’s exterior plays an important environmental role. The low-e glass help provide natural light without heat and make to cost for indoor cooling lower. The solar power generation equipment that makes up the microgrid system consists of two types of solar panels. High-efficiency polycrystalline solar panels are installed on the window surfaces of common areas on the east side of the building. Light-permeable, thin-film solar panels are deployed in other areas. The system also acts as the major structure for support conveying the floor a column free area. The prefabricated façade panel also help speeding up the construction time. Lighting system The main feature of gradation blinds is that their angles change automatically with the position of the sun. This helps keep the entire office bright by guiding sunlight efficiently, far into the building, while blocking direct sunlight and minimizing glare. All lighting fixtures in the office are designed as LED lights. Illuminance is automatically adjusted by sensors that detect the ambient office light. The lighting is configured to keep illumination for the overall work area subdued while keeping the areas around actual work surfaces bright. Dividing the light into ambient and task light can help using the energy more efficiently.


GROUP 4C

PROBLEM REPORT

ASCAS

CITY UNIVERSITY OF HONG KONG 2012


GROUP 4C

PROBLEM REPORT

ASCAS

CITY UNIVERSITY OF HONG KONG 2012



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