Dive Brief:

• San Diego Gas & Electric (SDG&E)and Sumitomo Electric have unveiled a 2 MW flow battery installation in Bonita, Calif.

• The vanadium redox battery will operate as a pilot program for four years as SDG&E tests the use of the battery for providing voltage frequency, power outage support and for shifting energy demand.

• The collaboration of SDG&E and Sumitomo came out of a partnership between Japan's New Energy and Industrial Development Organization and the California Governor's Office of Business and Economic Development.

Dive Insight:

Flow batteries hold promise, but they are still far behind lithium-ion batteries in market share. Flow batteries are less efficient and more costly than li-ion batteries, but they have a longer life and the lower degradation over multiple charge-discharge cycles.

Those differences are evident in SDG&E’s latest storage installation. The flow battery installation is a pilot project and is small in comparison with the 30 MW AES Energy Storage battery facility SDG&E recently installed in Escondido. But the flow battery will be able to provide backup power for up to four hours, and it has a useful life of up to 20 years, compared with 10 or 12 years for a li-ion battery.

"This pilot will advance our understanding of how this flow battery technology can help us increase the reliable delivery of clean energy to our customers and align with state and local carbon emission reduction goals,” Caroline Winn, SDG&E's chief operating officer, said in a statement.

SDG&E has been on the forefront of storage deployment thanks to regulatory support. California regulators pushed for expedited storage deployment to avoid potential blackouts stemming from gas losses at the Aliso Canyon natural gas storage facility last year.