FOLSOM, Calif. – An important milestone was reached recently when the California Independent System Operator (ISO) reported more than 5,000 megawatts (MW) of battery storage capacity online and fully integrated into the electrical grid. Elliot Mainzer, the ISO’s president and chief executive officer, said the 5,000 MW benchmark reached in early June reflects visionary leadership from California energy regulators and policy makers as well as hard work by staff at the ISO and storage developers. As of July 1, total battery storage on the grid had increased to 5,600 MW.
“With our state experiencing more frequent climate extremes such as record heat waves and droughts, it is essential to invest in innovative technologies like energy storage to make sure we can continue to reliably power the world’s 4th largest economy,” Mainzer said. “Just three years ago, we had about 500 MW on the grid and this rapid growth of energy storage in California has significantly improved our ability to manage through challenging grid conditions.”
With one megawatt of electricity providing roughly enough power to meet the demand of 750 homes, 5,000 MW of lithium-ion battery capacity can provide enough electricity to power approximately 3.8 million homes for up to four hours before the batteries need to be recharged.
The batteries being added to the grid are charged during the day, when solar power is abundant, and dispatched primarily in the evening hours when demand is still high and the sun is setting and solar capacity diminishing. Batteries are also increasingly being paired with new or existing solar resources at the same location because such facilities can provide greater operational efficiency and flexibility.
Texas has 3,200 MW of electrical storage currently.