"We’re experimenting with new battery technology to help ‘smooth out’ variations in load and generation output, and maintain stability in the local power distribution system."
Focus on Renewables Drives Innovation in Energy Storage
At the Wall Street Journal’s ECO:nomics conference in Santa Barbara, Calif., in March 2015, Edison International Chairman & CEO Ted Craver is asked what's ahead in energy storage technology. Will it prove cost-effective? His reply: “I’m more than optimistic about technological advancement.”
One of the World's Largest Energy Storage Projects
Our utility, Southern California Edison, recently unveiled the Tehachapi Energy Storage Project, a demonstration project funded by SCE and federal stimulus money awarded by the U.S. Department of Energy as part of the American Recovery and Reinvestment Act of 2009. It's one of the largest energy storage projects in the world.
Energy storage is a fundamental component of a greener, more resilient, more cost-effective grid.
It can play a role throughout the grid, and our utility is deploying residential energy storage units in a Home Battery Pilot Project, a larger energy storage system in a commercial Permanent Load Shifting Project, and several other projects on distribution circuits.
Our utility's Advanced Technology group also works closely with major battery manufacturers to evaluate their products. SCE has performed dozens of battery tests throughout the last 15 years to characterize the performance and lifetime of each vendor’s technology.
Our Smart Grid Demonstration, Co-Funded by DoE
The Irvine Smart Grid Demonstration (ISGD) is putting key smart grid elements to the test. Co-funded by a U.S. Department of Energy grant, the project evaluates technologies, including battery technologies, to assess their role in the emerging Smart Grid.
The Smart Grid is an increasingly intelligent and highly automated electric power system that incorporates technological advances in power system hardware, telecommunications, computing and more. The idea is power can be injected into or withdrawn from the grid at appropriate times to smooth out variations in load and generation output, helping to maintain the stability of a local distribution system.
“The whole purpose of ISGD is to test technology,” says Ardalan “Ed” Kamiab, project manager in our utility’s Advanced Technology group. “Maybe at some point, these technologies will become tools we can use to avoid building additional circuits or bringing additional generation online.”
Residential Energy Storage Units (RESU)
One of the advanced battery storage devices we’re testing at ISGD is the Residential Energy Storage Unit (RESU), which could have several valuable applications – for instance, in a neighborhood with an influx of electric cars.
Fourteen RESUs have been deployed in customer homes on the campus of University of California, Irvine; each can store 10 kWh of energy from the electric grid or from a customer’s rooftop solar PV system.
We hope to demonstrate how RESUs can reduce the added stress of electric cars and solar PV on a local distribution circuit. The RESU will be operated in a variety of modes, including demand response, to test this capability. In the event of an outage the RESUs also automatically provide back-up power for certain customer-selected loads (such as a garage door or refrigerator).
“When the owner of an electric car goes home at night and plugs it in, generally that’s charging off peak,” according to Bob Yinger, Consulting Engineer in our utility’s Advanced Technology group. “But what if they take it to work and want to charge during the day?”
Solar Power for Electric Cars
Meanwhile, in a parking structure at the University of California – Irvine, our ISGD team constructed a solar car shade system that connects 20 electric vehicle charging stations, a 48-kW array of solar PV panels, and a battery energy storage system (BESS). The team plans to demonstrate how energy storage and solar energy could support workplace charging of electric cars, without increasing the load on the grid.
Advanced Batteries for Residential Neighborhoods & Substations
Complex questions surround ISGD’s testing of two other energy storage systems. The Community Energy Storage (CES) device is being operated in a residential neighborhood, while the Distribution-Level Battery Energy Storage System (DBESS) is being operated at the substation level.