In Short : California has reached a significant milestone in its energy storage capacity, boasting over 6,600 megawatts (MW) of installed energy storage projects. This achievement highlights the state’s commitment to renewable energy integration and grid stability. With a diverse range of energy storage technologies, including batteries and other innovative solutions, California continues to lead in adopting sustainable energy practices. This substantial storage capacity enhances grid resilience, facilitates the integration of renewable sources, and contributes to the state’s ambitious clean energy goals.
In Detail : It wasn’t that long ago that a California energy storage news article would cover an installation such as one in San Jose with a 4 MW/28 MWh capacity. This project was completed in 2015, just 8 years ago, and yet the state of California has vaulted its total energy storage capacity today to just over 6,600 MW. In 2015, the total was less than 100 MW.
California’s rapid energy storage growth is a huge success and the Golden State is expanding its energy storage further. The California Energy Commission has an online dashboard illustrating the growth.
Remember when the knock on solar power and wind power was called the “intermittency problem?” But what happens when there is no sun and no wind, critics would say. Battery storage was, and still is, a big part of the answer. Ten years ago in California there wasn’t that much energy storage capacity though, meaning batteries may have not seemed like enough of a solution. Flash forward less than a decade, and California is solving clean energy intermittency and therefore the old “problem” is incrementally being faded into non-existence. If 6,600 MW doesn’t sound like that much, consider it is enough to supply electricity to about 6.6 million homes in California for 4 hours. California is nowhere near being finished with its energy storage expansion, as it plans to install far more as it moves toward operating fully on clean, renewable electricity.
How did the state of California grow its energy storage capacity to a little over 6,600 MW as quickly as it did?
California has targets of 19,500 MW of storage by 2035 and a goal of 52,000 MW by 2045. Because of these targets and the state’s efforts to speed the buildout of clean energy, California is the largest energy storage market in the world right now. Please see our Chair David Hochschild’s remarks on this.
We expect the momentum in storage buildout to continue as the CEC and its partner agencies (CPUC, CAISO) work diligently to address interconnection and energization issues. We will report more on this in our forthcoming IEPR report (a draft is due out in January), which this year specifically focuses on barriers and solutions to accelerate the connection (including interconnection, energization, and associated system upgrades) of clean energy technologies with the electric grid.
Of the more than 122,000 residential, commercial, and utility-scale battery installations, what is the breakdown for these types?
Residential: 843 MW, 119,483 installations
Commercial: 540 MW, 2,492 installations
Utility-scale: 5,234 MW, 106 installations
What are some of the primary benefits to having such a large energy storage capacity?
As the state shifts to wind and solar to meet California’s goal of 100% clean energy by 2045, energy storage is critical to make it work.
Wind and solar often produce more energy than can be utilized at the specific time it’s generated, but both resources also have periods when energy is not being generated at all (after sundown, and when winds are low). The main benefit of storage is the ability to store clean energy when it’s generated so it can be discharged during these low/no generation periods.
In California, electricity demand is highest in the late afternoon and early evening hours when the sun sets, causing solar resources to drop off before winds pick up later in the evening. The battery storage fleet provides a critical energy bridge during this time of day.
Are most of the state’s battery system lithium-ion battery chemistry? What other chemistries are being utilized, and are flow batteries being used?
Yes, the bulk of the state’s energy storage systems are lithium-ion. It is typically battery paired with wind or solar installations.
Will a portion of the energy storage growth come from homeowners who pair home energy storage with their home solar power systems?
Yes, this is the residential category in the dashboard. But as you can see, it is dwarfed by utility-scale storage projects in terms of total MW.