The geothermal activity below the Salton Sea loosens up lithium that can be mined.[2] The California Energy Commission estimates the Salton Sea might produce 600,000 metric tons of lithium carbonate (Li 2CO 3) per year,[3] of a reserve of 3.4 million tonnes.[4] The Salton Sea geothermal brine reservoir is located at depths of approximately 0.62 to 1.86 miles (1 to 3 km) below ground and contains fluids at temperatures ranging from 250 °C to 380 °C. Among other valuable minerals, the brine contains lithium (202 ppm ± 20% , i.e. more than in the Dead Sea, which is 30-40 ppm), rubidium (110 ppm ± 47%), cesium (19.8 ppm ± 15%), and bromine (91 ppm ± 31% vs 5000 ppm in the Dead Sea).[5] The lake also comprises chloride, sodium, calcium, potassium, and other low-value minerals that are difficult to separate.[6] All these minerals add up to the total salinity of 24.3 ± 2.8%.
The Lithium Valley Commission was created under the California Energy Commission in September 2020 to explore and expand the emerging lithium recovery industry.[7]
In 2016, the Australian firm Controlled Thermal Resources (CTR) announced plans to build a 140 MW geothermal power plant and a lithium extraction facility capable of producing 15,000 tons (13,600 tonnes) by 2023 and 75,000 tons (68,000 tonnes) by 2027. The company hopes to create a major new domestic source of the mineral.[8][9]General Motors announced a strategic partnership with CTR in 2021 to secure a local supply of lithium. The majority of the battery-grade lithium hydroxide and carbonate for the Ultium battery will come from this plant.[10]
Controlled Thermal Resources is developing a combined lithium extraction and power generation facility in the Hell's Kitchen geothermal field employing a closed-loop process. Brine will be extracted from the ground, with geothermal steam being used to drive a turbine generating electricity, and reacting with the brine to separate the lithium hydroxide and lithium carbonate used for battery production.[11][12]
Berkshire Hathaway Energy has a subsidiary that operates 10 geothermal plants in the area.[13] Berkshire's BHE Renewables division plans to open a lithium carbonate pilot plant.[6][14]
^Fernández, Caleb J. (August 31, 2021). "Lithium fuels hope for Salton Sea". KYMA. Associated Press. Archived from the original on September 4, 2021. Retrieved September 4, 2021.
^Alistair MacDonald and Jim Carlton. (February 8, 2022). "Where Is There More Lithium to Power Cars and Phones? Beneath a California Lake.". Wall Street JournalArchived May 21, 2023, at the Wayback Machine Retrieved February 9, 2022.
