As of early 2024, the Edwards & Sanborn solar-plus-storage project in Kern County, California, is the largest operational battery backup farm in the world.
The Darden Clean Energy Project (DCEP) in Fresno County, California, is estimated to cost over $2 billion to develop, rather than the $169 million figure often cited, which represents the project’s projected local economic benefits. Owned by Intersect Power, this 1,150 MW solar and 4,600 MWh battery storage project is considered the world’s largest, with construction anticipated to last 1.5 to 3 years.
Key Details of Edwards & Sanborn (California)
- Capacity: 3,287 MWh (Megawatt-hours) of battery energy storage, paired with 875 MWdc of solar PV.
- Infrastructure: The project features roughly 1.9 million solar panels and over 11,000 battery containers from LG Chem, Samsung, and BYD.
- Function: It is designed to store excess solar energy during the day and release it during high-demand, peak evening hours.
- Status: The project reached “substantial completion” and was fully operational as of January 2024.
Other Major Global Contenders
Before Edwards & Sanborn became fully operational, the Vistra Moss Landing Energy Storage Facility in California was the largest. It remains a top contender, with a 750 MW / 3,000 MWh capacity.
- Future Record Setter: The California Energy Commission approved the Darden Clean Energy Project in June 2025, which is projected to become the new largest in the world upon completion, with up to 1,150 MW / 4,600 MWh capacity.
- Global Projects: Other massive projects are appearing globally, such as the 19 GWh project planned in Abu Dhabi and various large-scale deployments in China, such as the 200MW/400MWh project in Hebei, which uses 628Ah ultra-large battery cells.
While other large-scale projects are under construction, Edwards & Sanborn currently holds the title for the largest fully operational facility.
