San Diego Gas & Electric (SDG&E) has been authorised by the California Public Utilities Commission (CPUC) to build three new energy storage facilities with a combined capacity of 161MW/644MWh.

According to SDG&E, the new facilities will give greater capacity to California to handle high demand for energy on summer days and at night following the dissipation of solar power.

Scheduled to be completed in late 2022 or early 2023, the three new energy storage facilities will be able to meet the power requirements of over 100,000 homes for up to four hours.

SDG&E energy innovation vice president Miguel Romero said: “Investing in advanced technologies like energy storage is critical to advancing our state and region’s aggressive climate goals, including getting to net zero greenhouse gas emissions, with the added benefit of making the energy grid more resilient.

“Project by project, step by step, we are making progress toward a cleaner, safer and more reliable energy future.”

To be owned and operated by SDG&E, the facilities will be linked to the state energy market. This will allow the California Independent System Operator (CAISO) to dispatch their power whenever required to balance demand and supply on the grid across the state.

By the end of this year, SDG&E anticipates owning 145MW of storage connected to the regional grid. This is equivalent to the power required to serve nearly 94,000 homes for a duration of four hours.

The Sempra Energy subsidiary is targeting to start commercial operation of a 20MW/80MWh lithium-ion battery storage facility in Kearny Mesa, California. It is also constructing a 40MW/160MWh lithium-ion storage facility in Fallbrook.

Last September, it had started commercial operation of the 30MW/120MWh Top Gun Energy Storage, a lithium-ion battery system in San Diego. Top Gun Energy Storage has the capacity to deliver the energy equivalent for serving 20,000 residential customers for a duration of four hours.