Jeremy tranter electrical project engineer solar inception silent power

Energy Storage for Emergency and Peak Load Management Clean Energy Week 2013 – ATRAA Stream 26th of July 2013 Jeremy Tranter BE (Hons) RPEQ NPER CPEng CEC Electrical Project Engineer

Overview  Energy Storage Trends  Energy Storage Technology  Energy Storage Drivers  Energy Storage Case Study  Financial Considerations

Energy Storage Trends  Increasingly strong industry focus on Solar+Storage  Solar+Storage market estimated to achieve US$2B by 2018 Source: NanoMarkets (December 2012)

 Cost of solar decreasing – electricity tariffs increasing  Cost of energy storage decreasing - with improved performance  Solar+Storage predicted cost cross over by 2014 Source: UBS (January 2013)

Energy Storage Drivers  Small Scale Solar – residential and small commercial users  Declining subsidies and rising electricity prices are improving the business case for Solar+Storage  Industry is responding with quality and innovative solutions

 Large Scale Solar – utility scale generation  Electricity markets and rules require reliable generation  Grid stability requires tight control of ramp rates, voltage and frequency  Storage coupled with power electronics (inverters) can ensure that intermittent generation supports high quality grid management

Energy Storage Drivers  Smart Grid & Dispatchable Energy  Demand charges & time of use tariffs drives the need for dispatchable energy  Automated and remote control of energy storage systems offer guaranteed supply when it is needed

 Emergency Power Supply  Uninterruptible power supplies are critical for many facilities with essential loads  Solar+Storage systems can provide emergency power for long periods without the need for diesel generators.

Energy Storage Technology  Lead Acid predicted to remain primary energy storage revenue generator for another decade (US$950M in 2018)

Source: NanoMarkets (December 2012)

 Lithium based technology a strong contender – with levellised costs already lower than lead acid  Other technologies becoming commercially available and viable: • Hydrogen • Sodium Sulphur • Zinc Bromine • Thermal/Eutectic • Vanadium • Capacitors

Energy Storage Technology

Source: Electricity Storage Association (November 2008)

Energy Storage Technology

Energy Storage System Configuration  Grid Coupled Energy Storage Systems  Backup only (UPS)  Parallel Generation – Peak Load Management  Backup & Parallel Generation

 Standalone Power Supply Systems  Renewable Only (Solar/Wind/Hydro)  Hybrid (Renewable + Diesel/Grid)  Diesel Only

Energy Storage System Configuration

Tony Ireland Stadium Energy Storage System Case Study Principal Townsville City Council Engineering Design Consultant Solari Energy Construction Contractor Tropical Energy Solutions

Project Background Townsville is one of seven Australian Solar Cities Tony Ireland Stadium  AFL, Soccer and Cricket Oval  1000 seat two storey grandstand & supporting facilities  Administration offices, meeting rooms, kitchens, medical rooms

Townsville City Council emergency management location

Project Location

Energy Storage PV Array

Project Brief  Grid Coupled Energy Storage System  Peak Load Shifting for the Stadium Lighting (30 kVA)  Dispatchable Energy from Solar PV System (40 kWp)  Emergency Power Supply for Disaster Management Capital Budget - $400k Solar Inception engaged as engineering design consultant

Technology Investigation  Multiple technologies considered for energy storage  Valve Regulated Lead Acid (Gel)  Lithium Polymer  Zinc Bromine

 Multiple manufacturers considered for inverter system  SMA Sunny Backup  ABB ESS-100  Selectronic SP Pro

Technical Solution  VRLA Gel (Sonnenschien) selected as energy storage technology  Lowest capital cost for highest energy storage capacity  Well understood and proven in the field long term  Fully supported by inverter manufacturers

 SMA Sunny Backup selected as inverter equipment     

World leader in inverter technology Modular and expandable Appropriate size available (30 kVA – three phase) Fully supports AC coupling SMA Sunny Tripower inverters already selected for solar PV system

System Specifications  6 no. SMA Sunny Backup 5000 inverters  30 kVA three phase power output nominal (50.4 kVA peak)

 1 no. SMA Automatic Switch Box XL  AS Box XL discontinued (late 2012)  Replaced with 2 no. SMA Automatic Switchbox L units

 96 no. Sonnenschein A602 2600 batteries  4 strings of 24 cells (48 V system)  502 kWh @ C20  600 kWh @ C100

System Integration  Direct connection into site Main Switchboard (1400 A)  Interconnection of new 40 kWp PV system  Installed as a separate contract (Tropical Energy Solutions)  Energy Storage System installed in purpose built shed  Inverters, switchgear and batteries with new submain to MSB  Ventilation to AS 4509 and AS 4086  Thermal management by natural ventilation and building fabric

System Operation – Normal Use  ESS charged primarily from solar during the day  Power injection from ESS into MSB during the evening  Power output matched to site loads  Fixed output (adjustable by programming) based on energy audit  Power injection controlled by time-clock – with future interconnection into BMS

 Maximum normal operation depth of discharge 50% (300 kWh)  Top up charge from grid during off-peak hours if required  Top up charge automatic based on battery DOD and time clock

System Operation – Emergency Use  ESS charged primarily from solar during the day  Option for portable generator to be connected

 Automatic islanding on grid power loss  20 ms changeover time  Power output load matched  Opportunity for future automatic load shedding from BMS

 Emergency operation depth of discharge 80% (480 kWh)  ESS reprogrammed (manually) for 80% DOD during emergency

Project Constraints  Large capacity VRLA battery systems large and heavy   

15.4 tonnes of batteries - ~18.2 kPA floor loading Second level plant room unsuitable – earthquake loads induced Custom built external battery room required – adding to project cost

 Outdated Australian Standards  

AS 4509 and AS 4086 poorly recognise Valve Regulated Lead Acid batteries Full ventilation and hazardous areas required for compliance

 Unknown connection requirements from DNSP (Ergon Energy)    

Ongoing issue…

New connection requirements released since construction – retrospective??

Potentially Network Study Required ($3,600) Potentially External Grid Protection Relay Required ($10k)

Expected Performance  Annual Average Daily PV Generation – 40 kWp in Townsville 

180 kWh/day

 100% of solar energy able to be stored for evening peak use  Typical Evening Power Injection – 30 kW for 5 hours 

150 kWh typical discharge C4 – approx 25-30% DOD

 Remaining solar energy fed to local loads or grid after ESS is charged  Potentially up to 5 days emergency operation in good weather   

~10 kW average load over 24 hours (load shedding) Reprogrammed for 80% DOD No input from genset

Financial Considerations ESS for Peak Load Management Not feasible from a purely economic viewpoint (yet‌) Payback > Battery Life Projects with multiple purposes & intangible benefits are possible and should be considered beyond $$$ Peak Load Management + Energy Shifting + Emergency Power Amenity + Education + Grid Support + Ancillary Services + ‌

Questions?

About Solar Inception and Solari Energy Solari Energy is a division Solar Inception Pty Ltd is an Australian owned and operated company that is a single-source provider of quality grid and off-grid solar power project solutions and professional services.

The company is equipped to meet small through large-scale solar project needs. Financially strong, with highest-quality manufacturing partnerships and an established distribution channel, Solari Energy is positioned for continued success and longevity in a shifting market.

The company serves clients through nationwide distribution, and also provides solar installation planning, design and implementation for commercial installations of all sizes. Solari Energy includes customers throughout Australia, Asia, New Zealand and the Pacific Islands.

For more information, visit www.solarinception.com.au, email info@solarinception.com.au, or contact the company directly at its offices in Queensland: 07 3166 9598 or Victoria: 03 9017 1010