Sunrun’s Puerto Rico Battery Network Powers 60,000 Homes, Supplying 45 MW to the Island’s Grid

Sunrun's home batteries in Puerto Rico were sent power to the island's grid for 18 consecutive days starting October 13, part of an extended stretch of unseasonably hot temperatures that stressed the electric system. According to the company, the run showed how thousands of household batteries can act as a single flexible resource when the grid is under its greatest strain.

That October dispatch is the most recent of more than 60 activations since April, when Sunrun began calling on its island-wide fleet to counter severe energy shortfalls and head off rolling blackouts.

Enrollment Doubles to 60,000 Customers

On November 3, 2026, Sunrun announced that participation in its Puerto Rico distributed power plant has doubled to more than 60,000 customers, together holding nearly 70,000 home batteries.

The fleet regularly delivers 45 megawatts of dispatchable power for four-hour periods, support the company describes as critical for an island grid repeatedly pushed toward shortfall.

Sunrun, the largest American provider of home solar, battery storage, and home-to-grid power plants, is also the biggest aggregator in Puerto Rico's Customer Battery Energy Sharing (CBES) program.

From 4,000 Customers to 60,000 in Two Years

The growth has been steep. Roughly 4,000 customers were enrolled in 2024. That figure climbed past 30,000 in 2025 and now stands above 60,000.

The expansion tracks with rising demand from the island's grid operator, which increasingly calls on home batteries to avert outages during periods of severe energy shortfall.

LUMA Credits Batteries With Avoiding Load Shedding

LUMA, Puerto Rico's electric utility operator, publicly acknowledged the fleet's contribution twice over the summer.

In statements issued in June and again in July, the operator said energy from home batteries helped "maintain system stability and prevent outages that would have affected thousands of customers."

LUMA added that it "overcame generation shortfalls and avoided the previously announced load shedding."

A Grid Where Outages Are Routine

The need for dispatchable household storage reflects persistent reliability problems on the island.

Citing U.S. Energy Information Administration figures, the company noted that Puerto Rico residents averaged 36 hours of power outages in 2025 unrelated to major events, a 19% increase over the prior year. Severe weather added another 23 hours of interruptions on top of that total.

How Customers Share Their Batteries

Participation is voluntary in scale as well as in kind. Each customer chooses how much energy to contribute, and most share only a small fraction of their total battery capacity. Sunrun says the design keeps enough reserve power for participants to ride out grid outages at home.

Customers are paid for the energy they share, and Sunrun earns recurring revenue from operating the aggregated fleet.

Powell Points to Mainstream Applications

Sunrun chief executive Mary Powell cast the island program as a template with a reach well beyond Puerto Rico.

"What began in Puerto Rico out of necessity for family resilience has become a vital blueprint for the U.S. mainland, where severe weather and the proliferation of AI data centers are demanding new energy solutions," Powell said. "Sunrun is uniquely positioned to provide these solutions, whether to support a grid at its breaking point or to provide capacity for hyperscalers looking to come online."