Geothermal energy could transform the way lithium is sourced

The southwest of England is famed for its dramatic coastline, verdant countryside and fresh seafood. If all goes to plan, another string could be added to the region’s bow over the next few years: lithium extraction.

In the county of Cornwall, efforts are underway to tap into the area’s natural resources and establish an industry which could, one day, produce both renewable energy and establish a local source of lithium.

Alongside its use in cell phones, computers, tablets and a host of other gadgets synonymous with modern life, lithium is crucial to electric vehicles and battery storage, two technologies with a big role to play in the planet’s shift to a low and zero emission future.

Examples of how this nascent sector could progress over the next few years include Geothermal Engineering Ltd, a company based near the Cornish town of Redruth specializing in the development and operation of geothermal projects.

Alongside its planned renewable energy operations, GEL is also working on a trial project centered around the extraction of lithium from geothermal waters. It’s a collaboration with another company, Cornish Lithium, via a joint venture dubbed GeoCubed.

“The aim is to demonstrate that lithium hydroxide, a key component of lithium-ion batteries used in electric vehicles, can be produced in Cornwall from naturally occurring geothermal water with a net zero carbon footprint,” GEL says.

The project in Cornwall is focused on direct lithium extraction, or DLE. According to the U.S. Department of Energy’s National Renewable Energy Laboratory, the technologies behind DLE “can be broadly grouped into three main categories: adsorption using porous materials that enable lithium bonding, ion exchange, and solvent extraction.”

While there is excitement about its potential, the NREL cautions it “remains a challenging task” to scale up the above methods to what it calls “full production capability.”

“For example, developing a solid material that bonds with just lithium is a huge challenge in geothermal brine that contains many minerals and metals,” it says.

Projects such as the one in Cornwall come at a time when concerns around sustainability and ESG are mounting. The security of global supply chains is another issue, especially when the vast majority of lithium production is currently dominated by countries including Chile, China, Australia and Argentina.

Against this backdrop, commercializing less intensive, more local and easily accessible ways of sourcing lithium could be hugely important going forward.

Major economies and automotive manufacturers are also laying out plans to increase the number of electric vehicles on our roads. Simultaneously, the push to expand renewable energy capacity shows no sign of letting up.

Julia Poliscanova is senior director for e-mobility at Transport & Environment, a campaign group headquartered in Brussels. Speaking to CNBC, she described lithium as being “irreplaceable for all of our green transitions.”

When it came to the sustainable sourcing of lithium and other materials, Poliscanova said that, “mid to long term, it’s clear that the vast majority of it has to come from circular business models, most notably recycling.”

She noted how there would be “really immense growth and demand” over the next few decades. This would require, in the short to medium term, new extraction techniques.

Expanding on her point, Poliscanova said the majority of lithium that will be in use in 2030 had not been extracted yet.

“That’s where geothermal lithium comes in,” she said, “because the new lithium, the new resources we … need, it has to be sustainably mined and has to be with the lowest impact on the environment and our communities.”

GeoCubed’s £4 million ($5.46 million) pilot plant will focus on a range of direct lithium extraction technologies. The overall objective is to eventually develop a commercial plant at GEL’s United Downs Deep Geothermal Power Project.

In an interview with CNBC, Ryan Law, GEL’s founder and managing director, outlined the opportunity his business was looking to capitalize on. Beneath its surface, Cornwall is home to a lot of granite rock which in turn has a high lithium content, Law explained.

“The combination of the granite rock being rich in lithium and hot water — hot water can absorb more lithium — means that the water that we bring to the surface at United Downs to drive our power plant has a very high lithium content,” he said.

“The next step is: how do we get it out?” Law went on to say. “And that’s what we’ve been looking at in conjunction with a number of partners.”

Changing times

GEL is one of several firms looking to develop facilities focused on direct lithium extraction. Alongside GeoCubed, Cornish Lithium is also working on a number of other projects.

Elsewhere, in April 2021, Australia-listed Vulcan Energy Resources said its direct lithium extraction pilot plant, located in Germany’s Upper Rhine Valley, had started operations.

In the U.S. in November, a firm called Controlled Thermal Resources announced that its drilling program at the Hell’s Kitchen Lithium and Power project in California had begun.

At the time, CEO Rod Colwell said the company was “on schedule to deliver the project’s first 50MW of baseload renewable power in late 2023 and an estimated 20,000 tonnes of lithium hydroxide in 2024.”

The Hell’s Kitchen project is attracting attention from some major players. Last summer, General Motors said it had “agreed to form a strategic investment and commercial collaboration with Controlled Thermal Resources to secure local and low-cost lithium.”

“As the first investor, GM will have first rights on lithium produced by the first stage of the Hell’s Kitchen project, including an option for a multi-year relationship,” the carmaker later added.

The above developments are in various stages of progression, but if they are able to produce at scale, it could lead to a sea change in the way lithium is harvested.

According to the NREL, the majority of lithium is sourced from “open-pit mines or lithium-containing saltwater beneath salt flats.”

It describes the latter as involving saltwater which contains lithium being “pumped into large basins where it evaporates under the sun.”

The environmental effects of such processes can be significant. The NREL says both open-pit mining and the salt flats method “can lead to land destruction, potential contamination, and high water consumption, notably in areas already suffering from drought and desertification.” It adds that they also take up a significant amount of space.

DLE, by contrast, allows for a “a more sustainable lithium supply, including using geothermal energy as the renewable power source for production.”

Transport & Environment’s Poliscanova went on to stress the importance of geothermal lithium complementing efforts on recycling and ideas about a circular economy. Recycling, she later said, should be the “number one priority.”

Recycling does indeed look like it will have a key role to play going forward, especially in the EV sector. Elon Musk’s Tesla, for instance, says all of its scrapped lithium-ion batteries are recycled.

And back in November, Swedish battery firm Northvolt said it had produced its first battery cell with what it described as “100% recycled nickel, manganese and cobalt.”

Back in Cornwall, the GeoCubed project continues. Earlier this month, it said it had chosen a firm called Ross-shire Engineering to provide its pilot plant with support related to engineering, procurement, construction and commissioning, or EPCC.

Its statement also referenced an electrical submersible pump test undertaken by GEL in August 2021, which resulted in the collection of “a bulk sample of geothermal water.”

GeoCubed said the levels of lithium concentrations in the sample were “encouraging,” and added that “other key by-products such as caesium, rubidium and potassium were shown to be at elevated levels.”

If all goes to plan, the pilot facility will be commissioned by the end of March this year.