The Salton Sea Lithium Opportunity: Geothermal Brine and the California Battery

In the Imperial Valley of southern California, sitting atop one of North America's most active geothermal zones, lies what may be the most strategically significant lithium resource in the United States. The brines beneath the Salton Sea geothermal field contain an estimated 18 million metric tons of lithium — enough, in theory, to supply the entire US electric vehicle market for decades. The Salton Sea has been called "Lithium Valley" for good reason. But extracting that lithium has proven far more challenging than the headline numbers suggest.

The Geology of the Salton Sea Resource

The Salton Sea sits at the northern end of the Gulf of California, where tectonic spreading has created an extremely hot, permeable subsurface environment. Geothermal operators have been extracting heat from this system for decades — the Salton Sea geothermal field is one of the largest in the world, with over 400 MW of installed capacity.

The same hot brines that power the geothermal plants contain extraordinarily high concentrations of dissolved minerals — including lithium at concentrations of 200-400 mg/L. For comparison, the famous Atacama brines in Chile average around 1,500 mg/L — but those resources are thousands of miles from North American battery manufacturing. The Salton Sea's lower concentrations are more than compensated for by their location and the fact that they're already being pumped to the surface for geothermal power generation.

The Co-Production Opportunity

The most compelling aspect of the Salton Sea opportunity is the concept of lithium co-production with geothermal power. The existing geothermal plants already pump enormous volumes of brine to the surface, extract heat, and reinject the cooled brine. The infrastructure — wellfields, pipelines, surface facilities — already exists.

Adding lithium extraction to this existing flow creates a fundamentally different economics story than greenfield lithium mining:

• Shared infrastructure: Wellfield development, brine handling, and water management infrastructure is shared with the power plant — dramatically reducing lithium-specific capital costs
• No additional water permits: The brine is already permitted for extraction and reinjection — lithium extraction inserts a processing step into an existing flow
• Renewable power co-location: The geothermal plant provides renewable power for the extraction process at on-site rates
• Regulatory pathway: Geothermal operations are well-regulated in California, providing a clearer path than novel mining operations

The Technical Challenges

Despite the compelling opportunity, the Salton Sea brines present serious technical challenges that have delayed commercial production for years:

Extreme Brine Chemistry

Salton Sea brines are extraordinarily complex. They contain not just lithium but also very high concentrations of sodium, potassium, calcium, magnesium, iron, manganese, silica, and dozens of trace elements. The total dissolved solids (TDS) content is 200,000-300,000 mg/L — nearly ten times saltier than seawater. Extracting lithium selectively from this chemical soup requires exceptional selectivity from the extraction technology.

Temperature and Scaling

The brines emerge at temperatures of 200-350°C. As they cool at the surface, dissolved minerals rapidly precipitate — a process called scaling — that can quickly clog equipment and membranes. Managing scale is one of the central operational challenges for any Salton Sea lithium project.

Silica Content

High silica concentrations in Salton Sea brines create particularly difficult scaling problems. Silica scale is hard, adherent, and difficult to remove. Geothermal operators have developed significant expertise in silica management; lithium extraction processes must be compatible with these existing management approaches.

Who's Working on It

The Salton Sea lithium opportunity has attracted significant investment and attention:

• Berkshire Hathaway Energy — the geothermal operator in the field — has invested in lithium extraction pilot programs
• EnergySource Minerals has been piloting adsorption-based DLE at the Salton Sea for several years
• Controlled Thermal Resources is developing an integrated geothermal + lithium project
• Lithios is deploying an electrochemical extraction pilot specifically designed for the challenging chemistry of Salton Sea brines

California has invested in the opportunity as well — the state has funded research, streamlined permitting, and set goals for developing Salton Sea lithium as part of its clean energy transition strategy.

Timeline and Expectations

Multiple companies have promised commercial-scale Salton Sea lithium production "within 2-3 years" for the past decade. The actual timeline has consistently proven longer. The technical challenges are real, and the gap between pilot-scale performance and commercial-scale reliability is significant.

A realistic view: first commercial-scale production from the Salton Sea is likely in the 2026-2028 timeframe for the most advanced projects. Full development of the resource to meaningful scale — tens of thousands of tonnes LCE per year — is a 2030s story. But the resource is real, the technology is advancing, and the strategic imperative of domestic lithium supply is only growing.