Home batteries in California delivered a record 745 megawatts (MW) to the state's grid on October 6, 2026, and Tesla Powerwalls supplied most of it. The figure comes from a Sunrun press release dated October 14.
What happened
Sunrun says its customers' batteries, working with Tesla, delivered 669 MW on October 5 and 745 MW on October 6. Sunrun lists the earlier records as 539 MW and then 580 MW. The company says 745 MW was enough to power all households in San Francisco and San Jose combined during peak hours.
The events ran during an October heat wave, at the request of the California Energy Commission and utilities. They were called under two state programs: Demand Side Grid Support and the Emergency Load Reduction Program. Sunrun says October 5 was the first time this year both programs called events at once across every participating investor-owned utility territory.
How much came from Tesla
Sunrun does not say how the total splits between its customers and Tesla's. Electrek reports that Tesla said on October 8 that more than 85,000 California Powerwall owners dispatched over 600 MW, which Tesla called the largest Powerwall virtual power plant event yet. Electrek's own estimate is that Powerwalls supplied roughly 80% of the total. That estimate is Electrek's, not a figure from Tesla or Sunrun.
For comparison, the September record was 580 MW, so the new total is about 28% higher.
What it means if you own a Powerwall
A virtual power plant links many home batteries so they can send stored power to the grid together at moments of peak demand. Sunrun says customers in these programs are compensated for helping strengthen grid reliability. Neither Sunrun nor Electrek gives payment amounts, and the sources do not explain how a Powerwall owner enrolls. Programs, payments and eligibility depend on your utility and location, so check with your utility or installer before assuming you qualify.
Sunrun says it has more than 120,000 home batteries enrolled in California grid programs.
