California Battery Storage Capacity: How Many MW the Grid Has

California battery storage capacity, year by year

The state reports battery capacity in its own releases, and the totals move quickly. In October 2024 the Governor's office put the total at 13,391 MW, and said the state had passed 10,000 MW earlier that year. In May 2025 it reported 15,763 MW. In November 2025 the CEC reported 16,942 MW. In May 2026 the CEC said additions in 2025 had taken the cumulative total past 17,000 MW. And on August 7, 2026 it reported 21,112 MW.

If you are searching for a single 2024 figure in gigawatts, the October 2024 number, about 13.4 GW, is the state's latest one for that year. For 2025, the figures run from about 15.8 GW in May to about 16.9 GW in November.

The jump in 2026 is partly real growth and partly accounting. The CEC's storage survey page says that beginning with its June 2026 update, the statewide total includes utility-scale batteries outside California that serve customers on the CAISO grid. Those resources were in the dataset before but weren't counted in the headline total.

Megawatts are not kilowatt-hours

The state's totals are in megawatts, a measure of how much power the batteries can deliver at one moment, not how much energy they hold. The CEC explains that it uses megawatts so batteries can be compared with the nameplate capacity of power plants, and notes that energy capacity is usually measured in watt-hours.

The practical link between the two is duration. The CEC says grid batteries can serve for short periods, typically two to four hours a day depending on system conditions, and that California's fleet is dominated by four-hour systems. A 100 MW, four-hour battery holds about 400 megawatt-hours.

Home batteries are labeled the other way around. A Tesla Powerwall 3's datasheet lists 13.5 kWh of energy and up to 11.5 kW of continuous on-grid output. When you read a state megawatt total, think of the output side of that spec.

How much of it is on homes

In its November 2025 release, the CEC broke the total down: 13,880 MW from large utility-scale projects, 2,213 MW from batteries on more than 200,000 homes, and 849 MW at businesses, schools and local government sites. The August 2026 release describes the smaller systems together, about 3,000 MW across more than 300,000 installations.

Home batteries are a small share of the total, but they grew fast. Lawrence Berkeley National Laboratory reported that 14 percent of California residential solar systems installed in 2023 included a battery. By the end of 2024, the CPUC says, nearly 70 percent of customers on the net billing tariff had paired a battery with their solar. The CPUC ties that to net billing, saying customers can maximize bill savings by installing storage so they can use or export stored energy in high-value hours.

Is Texas overtaking California in battery storage?

By the CEC's own description, Texas has caught up on total megawatts. The CEC's November 2025 release said California led all states and Texas was second with roughly 9,000 MW. By August 2026, the CEC described Texas as having a similar amount of total installed battery capacity.

The CEC's argument is about duration. It says Texas's batteries are mostly designed for discharges of two hours or less, while California's fleet is dominated by four-hour systems, so California's can deliver stored energy for about twice as long. If you are comparing the two states, compare megawatt-hours or duration as well as megawatts, or you are comparing different things.

Nationally, the U.S. Energy Information Administration counted 43.6 GW of operating utility-scale battery capacity at the end of 2025 and nearly 52 GW by June 2026. EIA's monthly inventory covers utility-scale plants, not the home batteries included in California's totals.

What the grid batteries actually do

Grid batteries charge when solar is plentiful and discharge in the late afternoon and evening, when solar fades and demand stays high. The CEC says that shift is displacing natural gas plants that used to ramp up at sunset. It reports that California used more solar than natural gas in the first half of 2026 for the first time, with solar use up 22 percent and gas use down 51 percent against the same months of 2024, while grid battery capacity grew 80 percent over that span.

The state also points to reliability. The CEC's May 2026 summer outlook noted that California has not called a Flex Alert in the summers of 2023, 2024 or 2025. The state estimates it will need more than 52,000 MW of battery and long-duration storage by 2045 as electrification grows, and says the August 2026 total puts it 41 percent of the way there.

What the statewide buildout means for your home battery

The same evening peak that makes grid batteries valuable sets the value of the one in your garage. Under the net billing tariff, the CPUC says export credits are usually lower than retail rates but can rise above them on late summer evenings. PG&E's 2026 export price sheet for customers who applied in 2025 or 2026 shows about $0.0085 per kWh for a weekday noon export in April and about $1.15 per kWh at 7 p.m. on an August weekday.

Grid programs also pay home batteries to act like small power plants. PG&E's Automated Response Technology program and the CEC's Demand Side Grid Support program both enroll batteries through providers to reduce load during grid events. Before you enroll, find out how often your battery would be called and how much charge the provider leaves you for your own outage backup.