Sunrun and Tesla put the September 9 home-battery dispatch at over 580 MW
Sunrun and Tesla said on September 21, 2026 that their home battery fleets dispatched more than 580 MW of peak power to California's grid for three hours on the evening of September 9, 2026: 517 MW from Tesla Powerwalls, 110,000 of which participated (55% Sunrun-owned), and 63 MW from what the release calls additional batteries; Sunrun separately dispatched more than 30,000 customer batteries from other manufacturers. The release ties the event to the CEC's DSGS price trigger and a PG&E call under the CPUC's ELRP, and calls it the largest distributed power plant dispatch event on record.