On a stretch of Sacramento County land where a nuclear reactor once generated controversy and kilowatts in roughly equal measure, construction crews are assembling one of California’s newer utility-scale battery systems. The Sacramento Municipal Utility District (SMUD) is building the Dry Creek Battery Energy Storage System on its Rancho Seco property, a 2,000-acre site about 25 miles southeast of Sacramento that housed a nuclear power plant from 1975 until local voters forced its closure in 1989.
The project, described in planning documents as a 640-megawatt-hour storage facility, is designed to pair with the Rancho Seco Solar II array already operating on the same property. Together, the solar panels and batteries would capture excess midday generation and feed it back to the grid during evening hours when demand peaks and sunlight fades.
What makes the Dry Creek BESS notable is not just its size but how SMUD got it approved. The utility threaded the battery project through an existing California Environmental Quality Act (CEQA) review, avoiding the years-long permitting process that slows most large-scale storage developments. That approach could offer a blueprint for utilities across the country sitting on retired power plant land they want to repurpose.
From voter revolt to solar-and-storage hub
Rancho Seco holds a singular place in American energy history. Its 913-megawatt pressurized water reactor, built by the Sacramento Municipal Utility District in the early 1970s, was plagued by operational problems, unplanned shutdowns, and cost overruns almost from the start. After years of poor performance, Sacramento voters passed Measure K in June 1989, making Rancho Seco one of the only commercial nuclear reactors in the United States shut down by public referendum…