Plenty of Salton Sea lithium for US EVs

The Salton Sea geothermal reservoir in Southern California could produce up to 3.4 million metric tons of lithium, which is plenty to make batteries for enough electric vehicles to replace all cars currently on U.S. highways, according to a comprehensive analysis carried out by the U.S. Department of Energy.

The analysis, funded by the Geothermal Technologies Office and conducted by DOE's Lawrence Berkeley National Laboratory, confirms the region's significant potential to support battery development for large, grid-scale stationary storage and EVs in the upcoming decades and adds to the case for continued private, state, and federal investment in the region.

As geothermal electricity production in the region expands, combining the abundant renewable energy with domestic lithium resources of this caliber would give the U.S. a leg up on the ambitious goal of net-zero emissions by 2050.

With continuing technological advancements, cost-effective extraction of minerals from geothermal brines would provide substantial domestic sources – not only for lithium but potentially zinc, manganese, and rare earths. Add in possible significant concentrations of precious metals like gold and platinum, and technologies capable of recovering metals dissolved in geothermal brines become even more appealing.

Funding innovation

The Geothermal Lithium Extraction Prize – one of the DOE's many American Made Challenges programs – seeks to drive further development of direct lithium extraction (DLE) from geothermal brines by partnering innovators and entrepreneurs with experienced industry experts to overcome challenges.

"We look forward to these teams developing innovative solutions that can make the United States self-reliant on a critical mineral that powers many aspects of our daily lives, now and in the future," said Kelly Speakes-Backman, principal deputy assistant secretary for energy efficiency and renewable energy.

Historically, the U.S. dominated the lithium market in terms of both production and end-use for decades until the 1980s, when foreign imports overtook domestic production.

DOE hopes that lithium drawn from Salton Sea geothermal brine and other domestic sources will break America's heavy dependence on imports.

"Strengthening our domestic supply chain will accelerate our efforts to decarbonize the economy –helping to power electric vehicles and boost grid storage and resiliency," said U.S. Secretary of Energy Jennifer Granholm. "We must seize the opportunity for the U.S. to lead an emerging global industry to create good-paying jobs for American workers that will be in demand for decades to come."

Because of the critical importance of lithium, the DOE's Geothermal Technologies Office is investing in research and development to support lithium extraction from geothermal brines in a variety of ways.

In at ground level

Automakers Stellantis and General Motors have already begun securing supplies of lithium from Salton Sea brines that benefit from the winning combination of geothermal power and mineral extraction with investments in Australian startup Controlled Thermal Resources' Hell's Kitchen geothermal lithium project.

"The foundation of our industry-leading decarbonization drive includes low-emissions production and sustainable supply as the building blocks for our electric vehicles," Stellantis CEO Carlos Tavares said. "The latest agreement with CTR is an important step in our care for our customers and our planet as we work to provide clean, safe and affordable mobility in North America."

Of primary concern is getting a secure domestic supply of battery-grade lithium extracted and processed with geothermal to the American market, weaning the country off more carbon dioxide-intensive imports.

"By securing and localizing the lithium supply chain in the U.S., we're helping ensure our ability to make powerful, affordable, high mileage EVs while also helping to mitigate environmental impact and bring more low-cost lithium to the market as a whole," said Doug Parks, executive VP of global product development, purchasing and supply chain at GM.

San Diego-based EnergySource, which also runs a geothermal plant at the Salton Sea, signed a contract earlier this year to sell lithium to Ford Motor Co.

The interest in this low-carbon resource and extraction combo is strong, and funding is available – the only remaining step is to quickly commercialize economically viable and scalable technologies to take advantage of this unique opportunity.