lithium extraction from geothermal energy plants

lithium extraction from geothermal energy plants

German scientists have suggested lithium for use in batteries could be extracted from geothermal energy plants to reduce reliance on imports

Pumping up thermal water, separating lithium, and using it to produce batteries for electric mobility – the idea of lithium as an environmentally compatible and regionally available by-product of geothermal energy plants appears highly promising.

However, it has not been clear so far whether domestic lithium extraction is really worthwhile.

A team of researchers from Karlsruhe Institute of Technology (KIT) has now summarised the state of the art, analysed raw materials markets, and assessed technologies.

According to them, it might be possible in theory to extract thousands of tons of lithium every year in Germany, but crucial aspects still need to be clarified.  

See also: Lithium-ion battery materials degradation better understood

lithium shortfall

For the energy transition, Europe needs a lot of batteries and sufficient lithium to produce them.

The European Union (EU) accordingly classifies lithium as a critical resource, but there is a danger of a lithium shortfall.

Valentin Goldberg, from KIT’s Institute of Applied Geosciences (AGW), said: “We are entirely dependent on imports. Worldwide, 80% of lithium resources come from Chile and Australia.

“At the same time, we deliberately accept major environmental expenses due to the conventional extraction of lithium in these countries, including negative impacts on groundwater.”

Lithium extraction in geothermal power plants, by contrast, is planned to be based on existing infrastructure in Europe, where large volumes of thermal water with a sometimes-high lithium concentration are being extracted.

Following energy production, lithium will be separated, and the remaining water will be fed back into the underground, as usual during operation.

Goldberg added: “In principle, we are very positive about this technology.

“Hardly any space would be needed, environmental and transportation costs would be low.”

To realistically determine the potential future share of domestic lithium, Goldberg and his colleagues from AGW have collected the available knowledge, analysed it, and for the first time calculated the potential for Germany. 

planned battery production

The potential lithium extraction volume does not only depend on the water’s lithium concentration, but also on the location-dependent flow rate and reservoir dimension.

For their estimations, the researchers analysed potential locations in Germany, studied markets of raw materials, and assessed various technologies in terms of efficiency, applicability, and integration in geothermal energy production.

AGW’s Dr Fabian Nitschke, who was also involved in the studies, said: “On this basis, we have obtained an optimistic annual production estimate of about 2,600 to 4,700 tons lithium carbonate equivalent, provided that all relevant geothermal energy plants are equipped with the necessary systems.

“With this, we could cover about 2% to 13% of the annual quantity needed for planned battery production in Germany.”

Construction of additional geothermal power plants might increase the extraction volumes.

However, it will take at least five years for a newly planned power plant to start operation.

In view of the predicted global lithium shortfall and planned battery production, the situation in Germany will deteriorate soon.

Nitschke added: “For this reason, lithium from geothermal power plants will nothing but complement imported resources in the medium term.” 

energy consumption

Prognoses still are subject to many uncertainties: the dimensions and the origins of lithium resources in geothermal systems as well as the response of the reservoirs to continuous extraction are being studied at the moment.

Moreover, extraction technologies are far from mature – essential development processes and long-term tests remain to be carried out.

Dr Tobias Kluge is another AGW author of the study. He stated: “But direct comparison already reveals specific advantages and drawbacks that are of particular relevance to economically efficient lithium extraction.

“The need for additional resources, damage caused by deposits in boreholes and extraction units, and energy consumption directly affect economic efficiency.” 

But it is not further technology development or suitable locations that will decide on whether lithium will be extracted at German geothermal power plants; public support and acceptance will be required.

Goldberg stated: “Our publications in the journal Grundwasser (groundwater) do not only address experts; we rather want to give decisionmakers in politics and industry, as well as the interested public, the chance to inform themselves directly and independently about opportunities and challenges.”

Now, the findings can be used as a basis for future research and development in this area.

Image: A geothermal power plant at Unterföhring near München. © Stephan Kelle 2016, https://www.geovol.de/

Leave a reply

Your email address will not be published. Required fields are marked *

Aether: Issue 3 Feb 2023

Aether: Issue 2 Nov 2022

Aether: Issue 1 Aug 2022

Subscribe for free

Latest Testimonial

What a beautiful motto: Discoveries must be read and not just published. When I was contacted by Aether as a new digital service to share scientific and technological insights I had my doubts that this was really going to be according to what I call the “open source & makers’ spirit”: knowledge should be free and it is there to be shared.

Well, Aether is faithful to its motto and shares discoveries freely. It has been a pleasure to collaborate for the interview and subsequent article. It has been greatly self satisfying to see how the interview was professionally and truthfully redacted and then published. Sharing thoughts and sparks for discussions is fundamental to the progress of society. Your journal offers clarity and brevity and I believe it provides the sparks to ignite any reader whether academic or not into action.

Dr Maria-Cristina Ciocci
Co-founder and Manager of non-profit organisation De Creative STEM,GirlsInSTEM