(Bloomberg) -- Sunrun Inc. is seeing a surge in US battery sales after California — the country’s biggest solar market — slashed rooftop subsidies in a move intended to boost backup power when the sun begins to set in the evening.

About 45% of the company’s new US sales comprised both solar and storage in the fourth quarter, the company said in a statement Wednesday. That’s up from 33% in the prior quarter and 15% at the beginning of last year. In California, about 85% of new sales featured solar and storage systems for the last two quarters of 2023, up from 20% before the state changed its rooftop incentive policy.

Read more: California’s Push for Rooftop Solar Panels Stalls as Jobs Vanish

California’s move to do so last April left the sector reeling. It led to bankruptcies and job cuts. 

For Sunrun, installation growth slowed to 3% last year, far short of its full year outlook of 10-15% released in the fourth quarter of 2022. The company — America’s biggest rooftop installer — sees 2024 solar installations down as much as 5%.

“We’ve moved to a solar-plus-storage company,” Chief Executive Officer Mary Powell said on an investor call Wednesday. She added the California solar market is growing faster than in the rest of the country for Sunrun, due in large part to the company’s increased focus on batteries. “We called 2023 the year of storage, and we were leading with storage.”

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