If the electric car boom should boost the demand for lithium, the exploitation of this metal raises real environmental questions. As reported CNBC, initiatives to make this operation more “green” are multiplying. In the UK, in the county of Cornwall, the company Geothermal Engineering Ltd (GEL) is working to use the properties of geothermal energy.
Lithium extraction, still essential
Lithium is already present everywhere in our lives. It is found in our cell phones, computers, tablets and many other electronic devices. It is also found in electric cars, the number of which is expected to be multiplied. Bearing in mind that a Renault Zoe battery can contain up to 8 kilos of lithium, 1.2 million electric vehicles and one million hybrid vehicles were sold in Western Europe in 2021.
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While current lithium-ion batteries can be improved, lithium remains essential for the production of future cars. After a 400% increase in its price in 2021, its demand should continue to increase in the coming years. For Julia Poliscanova, the director of a Brussels group focused on electric mobility, this metal is “irreplaceable for our green transitions”.
In the long term, the vast majority of lithium must come from recycling. The expert, however, believes that in the coming decades, lithium should experience “Really huge growth and demand. » Extraction will therefore play a central role in the more or less near future. Still according to Julia Poliscanova, the majority of the lithium to be used in 2030 has not yet been extracted.
Reducing the impact of lithium on the environment
Problem: this extraction is synonymous with pollution. Mainly carried out in brines and in a rock called spodumene, it involves, depending on the processes used, CO2 emissions, soil degradation and significant water consumption. Its effects are particularly feared in areas that are already suffering from water stress.
To overcome these problems, Geothermal Engineering Ltd intends to use what the company does best: using geothermal energy, i.e. recovering the heat present in the subsoil, in order to reduce the carbon footprint of exploitation of lithium and make it more environmentally friendly.
GEL is currently running a pilot project in Cornwall County, Cornwall. The subsoil of the region being particularly rich in lithium, the region could become a major economic player in this field if the GEL project succeeds. However, the company is seeking to improve this exploitation of the granite rocks in the basement, rich in lithium, without harming a region renowned for its coastline and its seafood.
In partnership with another company, Cornish Lithium, they created a joint venture called GeoCubed. The duo hopes to develop new methods for extracting the precious metal, focusing in particular on the issue of CO2 emissions. In a statement, GEL says: “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 natural geothermal water with a net zero carbon footprint. »
Large-scale production is not for now
GeoCubed’s United Downs Deep Geothermal Power project focuses on DLE, to Direct Lithium Extraction. This direct extraction combines three aspects: lithium absorption and binding, ion exchange and solvent extraction. In the pilot plant, which cost £4,000,000 (around €4,755,000), they are to study the potential yields and properties of geothermal water.
This water being hot, it effectively captures the lithium better. Ryan Law, the founder and managing director of GEL, indicates that the water used by its power plant has a very high lithium content. It would be enough to separate the lithium to benefit, in addition to electricity production, from a metal extracted in a way that is more respectful of the environment.
The answer to this problem, however, is not straightforward. How to recover the lithium? The US Department of Energy’s National Renewable Energy Laboratory (NREL) says it’s enthusiastic about the potential of the process, but warns that there are still “a difficult task” to expand production capacity. Knowing that the geothermal brine contains many minerals and metals, how to recover only the lithium and separate it from the other components?
When will green lithium be available?
Ryan Law replies: “That’s what we looked at together with a number of partners. » The leader admits that the technology is not yet ready for large-scale use. However, the proliferation of projects linked to geothermal energy calls for optimism.
Last April, the company Volcan Energy Resources started its direct mining activities in the German Upper Rhine.
In the US, Controlled Thermal Resources CEO Rod Colwell said his company was “on schedule” on a similar project. By the end of 2023, it intends to deliver its first 50 megawatts of renewable energy, as well as 20,000 tonnes of lithium hydroxide in 2024. A project that has already attracted the attention of General Motors.
All of these projects have reached different stages of maturity. If nothing is certain, the potential of geothermal energy in the production of lithium is real. This could help put geothermal energy back at the forefront of the renewable energy scene. In France, the production of geothermal electricity remains extremely marginal: although France has other exploitable sites, only the Bouillante site, in Guadeloupe, produces geothermal electricity industrially. It produced 110 GWh in 2019, or 6% of the island’s electricity production.
For Julia Poliscanova, geothermal lithium must be encouraged without becoming the number one priority. It should only complement other battery recycling efforts and other circular economy initiatives. In the meantime, the GeoCubed project continues. In addition to raising levels “encouraging” of lithium, the sign declared having detected other interesting elements, such as cesium, rubidium and potassium. If all goes as planned, the pilot plant should go live this month.