Home batteries operated by Sunrun and Tesla delivered a record 745 megawatts of peak power to California’s electricity grid on October 6, helping meet elevated demand during a prolonged heat wave.

The dispatch surpassed the 669 MW delivered a day earlier, setting consecutive records for residential distributed power plants in the United States, according to Sunrun’s October 14 announcement.

At the request of the California Energy Commission and utilities, the companies discharged batteries installed in homes during multi-hour evening peak periods. 

Sunrun said the coordinated releases increased the grid’s operating margin and put downward pressure on real-time electricity prices.

The October 6 dispatch delivered enough peak power to supply all households in San Francisco and San Jose combined, according to Sunrun. It demonstrated how batteries spread across individual properties can collectively provide a substantial source of electricity when demand rises.

Both evenings involved California’s Demand Side Grid Support (DSGS) program. Dispatches were triggered after the California Independent System Operator’s day-ahead locational marginal electricity price exceeded $200 per megawatt-hour.

The October 5 event also marked the first time this year that DSGS and the Emergency Load Reduction Program called for concurrent dispatches across all participating investor-owned utility service territories. By coordinating residential batteries, the programs tapped energy infrastructure already installed in homes to support the wider electricity network during periods of heightened demand.

The back-to-back events exceeded the previous residential distributed power plant record of 580 MW, set on September 9, 2026. That dispatch had surpassed the 539 MW delivered on July 29, 2025.

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