The farmers who have worked the Imperial Valley for over a century knew the ground beneath them was hot. They knew the Salton Sea sat over one of the most geothermally active zones in North America, and they knew that the geothermal plants on its southern shore had been generating electricity for decades. What most of them did not know — what most of the country did not know — was that the superheated brine circulating miles underground contained lithium at concentrations more than five times those found in the Dead Sea. The area adjacent to the Salton Sea's southern shore is now called Lithium Valley, and it may hold the key to America's electric vehicle future.
The Salton Sea Geothermal Brine reservoir sits at depths of roughly one to three kilometers below the surface, where temperatures range from 250 to 380 degrees Celsius. The brine — a dense, mineral-laden fluid dissolved from surrounding rocks over geological time — contains lithium at approximately 202 parts per million. For comparison, the Dead Sea, long considered one of the world's most mineral-rich bodies of water, holds lithium at only 30 to 40 parts per million. The California Energy Commission has estimated the reserve at 3.4 million tonnes, with a potential annual yield of 600,000 metric tons of lithium carbonate if full extraction infrastructure were developed. The brine also contains significant concentrations of rubidium, cesium, and bromine — a mineral cocktail of considerable commercial value.
What makes Lithium Valley unusual among potential lithium sources is that the infrastructure to access the brine already exists. The eleven geothermal power plants operating in the area pump brine to the surface to drive turbines, extract the heat, and then reinject the cooled fluid underground. The lithium and other minerals dissolved in that brine have been cycling through this process for decades, largely ignored. The insight driving current development is that the same fluid that generates electricity can also yield lithium as a byproduct — a closed-loop process where power generation and mineral extraction happen simultaneously, with the brine returning to the ground carrying less of its lithium than it brought up. This co-production model, if it performs at scale, would make the Imperial Valley's lithium dramatically cheaper to produce than lithium mined conventionally from hard rock or evaporation ponds.
The scale of interest from industry signals how seriously the opportunity is being taken. General Motors entered a strategic partnership in 2021 with Controlled Thermal Resources, an Australian firm developing the Hell's Kitchen geothermal field within the lithium zone, specifically to secure supply of battery-grade lithium hydroxide and carbonate for its Ultium battery platform. The Ultium battery underpins GM's entire electric vehicle transition, and the company's investment reflects a judgment that American domestic lithium supply is both strategically important and commercially viable here. Berkshire Hathaway Energy, through its BHE Renewables subsidiary, has separately announced plans for a lithium carbonate pilot plant. The Lithium Valley Commission, established under the California Energy Commission in September 2020, was created to coordinate and accelerate the emerging industry.
The gap between the reserve estimates and actual production is where the complexity lives. Extracting battery-grade lithium from geothermal brine at commercial scale requires technology that is proven in laboratory settings but not yet demonstrated at the volumes that the projections assume. Imperial County, which stands to benefit most from the economic activity — the county has historically high unemployment and poverty rates — has been watching the permitting and pilot processes with understandable impatience. The name Lithium Valley was coined with a deliberate echo of Silicon Valley, suggesting a comparable transformation of a peripheral California region into a global economic center. Whether the geology, the technology, and the capital can align to make that happen is a question the next decade will answer.
Lithium Valley is centered at approximately 33.19°N, 115.56°W, adjacent to the southern shore of the Salton Sea. The geothermal power plants that define the landscape are visible from altitude as industrial clusters amid agricultural fields, with cooling towers releasing steam. The Salton Sea is directly to the north. Imperial County Airport (IPL) is approximately 10 miles south. The area around the Salton Buttes volcanic domes at the sea's southern tip marks the heart of the geothermal zone.