The 30 megawatt (MW) energy storage plant at Escondido, CA, has a capacity of up to 120 megawatt-hours of energy. It could serve 20,000 customers for 4 hours.
A smaller, 7.5 MW installation was erected in El Cajon.
“On a day (like Friday), which is nice and sunny, but also cool, demands for energy in the middle of the day aren’t very high but production is. So we’d be storing solar in the day and releasing it at 6:00–7:00 tonight after everyone’s home from work, and school, and home with their families. It’s a tool that we can use to make the integration of solar and wind much more reliable and better matched to the times when our customers need it most,” said Josh Gerber, Project Director SDG&E.
“Even though this is the largest energy storage project in the world, it came online in about six months. So it is one of the quickest installed projects in the world as well,” said John Zahurancik, AES Energy Storage president.
“These projects affirm our commitment to deliver clean energy to customers and to provide a more reliable power supply to our electric grid when it is most needed,” said SDG&E’s president, Scott Drury.
These two plants are the first steps in SDG&E’s compliance with the CPUC regulations that it must procure a total of 165 MW of energy storage by 2020, and it must be operational by 2024.
SDG&E intends to develop, or interconnect, more than 330 MW of energy storage by 2030.