Geothermal energy facilities could be a source of lithium

September 12, 2014 0 By Amanda Giasson

The brine in the wastewater from geothermal plants could be used for creating the alkali metal.

Mining lithium from geothermal energy plants is a clever idea that comes from Simbol Materials, a southern Californian based company that takes the brine that ends up as part of the wastewater from the geothermal process and extracts it to create lithium, which is an alkali metal used for making batteries.

The new process has some advantages over current lithium mining methods.

The vast majority of global lithium production occurs in Chile and Argentina. Brine is removed from underground and is gradually concentrated in the sun’s heat. This is a very slow process and the cost of constructing the pipes that are needed underground to extract brine and manage leftover waste are very high. However, Simbol does not need to concern itself with these setbacks because it can utilize the existing infrastructure that has been set up for geothermal power plants.

In California’s Imperial Valley there are around ten or so geothermal facilities that are already built and in operation. These plants extract hot, salty brine from deep beneath the ground and use it to create steam, which, in turn, produces electricity. Typically, the brine (which is still warm) becomes wastewater and is pumped back under the earth.

Geothermal Energy - Lithium chunk of metalInstead of allowing the brine to be pumped back down, Simbol Materials redirects the warm brine and extracts the lithium by passing the brine through membranes and filters. Currently, the company has already managed to mine a few hundred tons of lithium. It is believed that if Simbol can efficiently expand to a commercial-scale facility, it would have advantages over present mining practices for lithium.

Geothermal energy facilities could play a role in the future of batteries.

The demand for lithium is likely to go up, which makes it a good time to be a producer of this metal. In fact, Tesla Motors is building a gigafactory for car batteries and, when the company was deciding which U.S. state would serve as the site for its gigafactory, Simbol was considered to be a possible bonus for California. However, Tesla ended up choosing Nevada, which is home to America’s only lithium mine that is commercially active.

However, how the chemical substance is mined in the future could change, especially if geothermal energy plants become a viable resource.