More than 140,000 Sunrun and Tesla home batteries sent a record 580 MW to California’s grid during a three-hour evening period in the Sept. 9 heat wave. About 110,000 Tesla Powerwalls supplied 517 MW; 30,000-plus other batteries contributed 63 MW.
The power reached the grid through California’s Demand Side Grid Support program and the Public Utilities Commission’s Emergency Load Reduction Program. Sunrun delivered another 140-plus MW on Sept. 10 at Southern California Edison’s request. Electrek reported the combined output was enough to meet Sacramento County households’ needs during peak demand.
In a virtual power plant, program operators can draw electricity stored in enrolled homes during high-demand periods or grid emergencies. Homeowners may receive compensation, while the batteries can also provide backup power.
