Market update · Global
Battery Storage Integration with U.S. Residential Solar Systems Reaches 37% in 2025
In 2025, battery storage was paired with 37% of new U.S. residential solar installations, marking a significant increase from 25% in 2024. This growth is driven primarily by California's market and policy changes, with notable adoption increases in other states as well. Non-residential solar storage adoption also rose but remains lower than residential levels.
SolTraCo market update · · 3 min readGrowth in Battery Storage Adoption with Residential Solar
Battery storage was integrated with 37% of new U.S. residential solar installations in 2025, up from 25% in 2024, indicating a rapid acceleration in adoption. This shift reflects batteries moving from an optional add-on to a standard component of rooftop solar projects.
By the end of 2025, approximately 3 million distributed solar and solar-plus-storage systems had been installed in the U.S., including about 450,000 systems installed during 2025, which represent an estimated 93% of the U.S. residential solar market.
California as a Major Driver of Solar-Plus-Storage Growth
California led the trend with about 74% of new residential solar installations including battery storage in 2025, up from 58% in 2024. More than half of California solar customers paired batteries with their systems by late 2025, a sharp increase from about 20% in October 2023.
This rise is linked to California's transition to the Net Billing Tariff (NEM 3), which reduced the value of electricity exported by rooftop solar customers and increased the value of storing excess daytime generation for later use, thereby altering the composition of the rooftop solar market.
Increasing Battery Storage Adoption Outside California
Battery storage adoption outside California more than doubled from 7% in 2024 to 17% in 2025. States such as Arizona and Texas saw particularly large increases in residential storage attachment rates.
This growth is attributed to changes in net-metering structures and time-of-use electricity rates in various markets, which enhance the value of consuming stored solar power rather than exporting it.
Non-Residential Solar Storage and System Capacity Trends
Storage adoption in the non-residential solar market increased from 7% in 2024 to 12% in 2025, with California's non-residential attachment rate rising from 12% to 18%, and other states doubling from 4% to 8%. However, non-residential storage adoption remains significantly lower than residential levels.
While the median residential storage capacity remained steady at 13 kWh, the median discharge capacity increased sharply from 6 kW in 2024 to 11 kW in 2025, largely due to the growing deployment of the Tesla Powerwall 3, which offers higher discharge capacity.
Sources
This update is an original SolTraCo synthesis of the linked industry sources. Reported facts and commercial interpretation are kept separate. It does not contain confidential deal information and is not investment, legal or technical advice.