Sunrun and Tesla dispatched a combined 580 megawatts (MW) of power to California's electricity grid from over 140,000 home batteries. The dispatch occurred on September 9 during a period of extreme heat and elevated demand.
Tesla Powerwalls accounted for 517 MW of the total output, with Sunrun owning and operating 55% of these units. Sunrun contributed an additional 63 MW from over 30,000 batteries from other manufacturers. The combined output was sufficient to power all households in Sacramento County during peak hours.
The dispatch was triggered when the California Independent System Operator's day-ahead locational marginal price exceeded $200 per megawatt-hour. Participants in the California Energy Commission's Demand Side Grid Support (DSGS) program received direct compensation for the power they shared with the grid.
On September 10, Sunrun and Tesla delivered more than 140 MW of battery capacity to the grid during a separate three-hour peak dispatch requested by Southern California Edison. Earlier in the month, Sunrun, Tesla, and Renew Home announced plans to enroll nearly 21,000 flexible energy devices into a Google-funded distributed power plant with Pacific Gas and Electric Company (PG&E).
By 2028, a commissioned report by The Brattle Group found that such programs could provide up to $206 million in net cost savings to Californians. A Google-funded distributed power plant involving Sunrun, Tesla, and Renew Home with PG&E is expected to begin supporting the grid this fall.
