A new, efficient, and low-cost commercial battery for the smart power grid is powering up as a 100 kW sub-system on the campus of the City College of New York. This is the first stage of a 100 kW, 200 kWh battery to be completed by the end of July 2013. The technology was developed by the CUNY Energy Institute with support from the Department of Energy, NYSERDA, and Con Edison and has been exclusively licensed to Urban Electric Power (UEP) for electricity storage and management. For over a year, this technology has been in operation as a 30 kWh lab demonstration for peak shaving.

Cost-competitive grid-scale energy storage (for peak shaving, renewable firming, and transmission and distribution deferral) requires batteries with much lower lifetime costs per kWh than has been previously available. For the past ten years, researchers have worked to develop new battery technologies that can compete in these markets. Urban Electric Power’s zinc anode battery technology is the first of these to transfer from the lab to market. UEP’s new GreenCat zinc-nickel oxide (Zn-NiO) rechargeable battery systems are able to meet these ambitious cost targets because they are capable of achieving many more cycles than previous generations of zinc anode batteries. Urban Electric Power’s advanced zinc anode batteries provide performance similar to a lithium ion battery for the price of a conventional lead acid battery per delivered kWh. These novel zinc anode batteries are safe, non-toxic, and 100% recyclable and operate without capacity loss for many years. They do not require special handling or cooling equipment.

Urban Electric Power
This company has exclusive rights to two novel zinc anode rechargeable battery technologies that were developed by the CUNY Energy Institute under the leadership of distinguished professor of chemical engineering, Sanjoy Banerjee, PhD, with support from the Department of Energy, NYSERDA, and Con Edison. Both battery types contain zinc anodes but have different cathodes (nickel oxide or manganese dioxide). Zinc anode batteries were invented over 100 years ago and are trusted for their safety, reliability, and high energy density. Previous generations of zinc anode batteries have been limited to 300 to 500 cycles, making them too expensive and inadequate for most important applications. The patent-pending innovations developed at the CUNY Energy Institute let UEP’s zinc anode batteries attain significantly longer lives.

Flow-assisted battery technology
The GreenCat Power batteries operating in UEP’s 100 kW peak shaving system use zinc-nickel oxide flow-assisted technology. The addition of flowing electrolyte prevents the zinc dendrite growth and electrode deformation that have led to premature battery failure in the past. UEP’s flow-assisted batteries with high-quality nickel oxide cathodes are able to recharge for over 5,000 deep cycles while retaining more than 80% of their capacity. These Zn-NiO batteries are appropriate for peak shaving, peak shifting, power protection, forklift operations, and solar and wind firming.

Ultra low-cost zinc-manganese dioxide technology
UEP’s next generation GreenCat battery product uses a much less expensive manganese-dioxide cathode that lowers the battery price to under $100/kWh with stable performance for over 2,000 cycles. The Department of Energy’s Advanced Research Projects Agency-Energy (ARPA-E) supported the zinc-manganese dioxide (Zn-MnO₂) research at the CUNY Energy Institute as part of the Grid-Scale Rampable Intermittent Dispatchable Storage (GRIDS) program. $100/kWh is DOE’s cost target to unlock the market for grid-scale energy storage. At this price, UEP batteries can also compete with lead acid batteries for uninterruptible power supply (UPS) applications and automotive starting, lighting, and ignition—the largest existing rechargeable battery market. Urban Electric Power is looking for strategic partners to expand commercial adoption and licensing of both technologies.

Leveling  energy demand and reducing the cost of peak electricity
Urban Electric Power’s battery technology delivers low-cost energy storage that reduces the delivered price of electricity for multiple markets, solving the problem that electricity supply and demand are not coupled in real time. Energy is often needed at times and places where it cannot be generated. Building the transmission and distribution infrastructure to deliver electricity is expensive and time-consuming, making reliable electricity expensive in some areas.

For peak shaving customers in urban distribution areas, UEP’s GreenCat Power battery systems will distribute electricity demand throughout the day to reduce demand charges, which can make up half of the cost of energy bills in congested areas. In peak shifting applications, UEP batteries are charged using lower cost off-peak electricity and set to release electricity when retail rates are higher. UEP batteries are able to back up intermittent renewable sources to smooth out generation throughout the day, preventing grid instability and voltage sags. As well, the technology can serve the large industrial uninterruptible power supply (UPS) market.

 Urban Electric Power
www.urbanelectricpower.com