Battery storage is becoming a bigger part of electricity systems around the world, and California offers a clear example of why that matters. Storing energy when it is plentiful can make solar more useful later in the day, when homes still need electricity.
For homeowners considering solar and batteries, the wider trend is encouraging. Understanding what the numbers measure helps connect that progress to a realistic plan for your own property.
Worldwide battery additions grew sharply in 2025
The International Energy Agency's Global Energy Review 2026 reports that the world added 108 gigawatts of battery storage capacity in 2025, about 40% more than in 2024. Roughly four-fifths of those additions were utility-scale; the remainder served commercial and residential customers behind their electricity meters.
Those figures describe battery storage for power systems, rather than electric-vehicle batteries. They also describe additions during 2025, not a forecast for 2026. The growth spans markets with different electricity rules, so it does not establish a particular California household's price or savings.
California's milestone includes several kinds of storage
In an August 7, 2026 announcement, the California Energy Commission reported 21,112 megawatts of battery storage serving Californians. The total includes large facilities within California, resources in Nevada and Arizona serving the CAISO grid, and smaller systems at homes and other properties.
The CEC's storage survey, with data current to June 15, 2026, explains that its displayed statewide total now includes those out-of-state resources. This is a measure of storage supporting California, not exclusively batteries physically inside its borders.
These megawatt figures measure power capability. They do not tell you how many hours every battery can operate. The CEC describes storage helping carry abundant renewable generation into later hours, when electricity is still needed.
What does grid growth mean for home backup?
Our takeaway is that a stronger storage fleet and a household backup system address related needs at different scales. Grid storage helps balance electricity supply and demand. A home's outage plan still depends on equipment that can safely supply that property when grid service is unavailable.
PG&E's residential battery guidance explains that backup often serves selected circuits, with duration depending on battery size, household use and solar availability. Ask your installer to identify the supported appliances, reserve settings and conditions for solar recharging. For local planning, see our PG&E guide or SCE shutoff-preparation guide.
A solar-plus-battery PPA can bring the idea home
For eligible homeowners, a qualifying PPA with included battery equipment and no upfront payment can be a compelling way to access solar and storage while preserving cash.
The provider owns the solar system and charges for its generated electricity. Confirm battery ownership, backup configuration and service coverage, then review the rate, any escalator, term and home-sale provisions using the CPUC's consumer guide. Ongoing PPA payments and remaining utility charges belong in the comparison; global deployment growth does not guarantee personal savings.
Start with your home's priorities and an actual proposal. Explore the homeowner journey, then request a consultation with a West Coast Alternatives energy specialist.