DECODING – While scientists were gathered from the 25th to the 29th of March in Japan for the second part of the IPCC’s 5th report, the question of energy transition could brush against that of resources. How indeed could we exploit renewable energies while metal and ore reserves are running out ? In the review Nature Geoscience two researchers from the ISTerre are blowing the whistle.
Is wind energy a green energy ? Is solar energy a renewable energy ? If the answer is obvious, what about the infrastructures for producing this type of energy ? Multilayered panels of solar systems, wind energy mats, blades and engines do need materials and ore to work.
« By 2050, we will need six or seven times the current global production of steel for the only sectors of renewable energies », declares Olivier Vidal in an interview published on the website of Joseph-Fourier’s university whose work has been the subject of an article published in the review Nature Geoscience.
The CNRS” director of research at the laboratory of the ISTerre focused on the question of the world’s mineral and metal resources. Do we have enough resources to assure energy transition ? According to this scientist, the capture and exploitation of renewable energies require, with an equivalent production capacity, more basic materials than fossil and nuclear energies.
Green energies, big metal consumers
Wind energy and solar systems use up to 90 times more aluminium, 50 times more iron and 15 times more concrete than power plants which exploit fossil resources. And by 2050, the energy transition will require an increase of 10 to 18 % of these elements” primary production. In short, we will urgently have to find a certain amount of concrete, aluminium, iron, copper… But also rare earth, these metals with neighbouring chemical properties that have become essentials in High tech industry and green energies. « With wind energy systems, we are using permanent magnets that require between 200 and 600 kg of rare earth per megawatt (MW) of power, considering that a classic wind system needs 2 MW and that new offshore wind systems need 6 MW, explains Olivier Vidal. We also have solar panels for which we are transiting from silicon panels to multilayered panels with gallium, selenium and copper. These are developing technologies that use uncommon elements. »
Coveted rare earth whose extraction, however, is hard and polluting, is in the hands of China… And the emerging countries” demand is increasing. « China currently uses 30 % of global copper and aluminium and 50 % of global iron », continues Olivier Vidal.
Yet, the trend should not reverse for a long time. In the future, we will need more raw materials to exploit renewable energies and more energies to extract metals with a lower concentration… The cycle has been completed. The deposit could well dry up. Especially as it takes several million years to renew the metal and hydrocarbon reserves.
There are few studies focusing on the real cost of these technologies
A study led by the Centrale engineer Philippe Bihouix mentions thirty to sixty years of reserve for most of the big industrial metals such as zinc, copper, nickel and lead. The available indium reserves, used in particular in photovoltaic cells, would be limited to twenty years… and those for copper, thirty years.
China has massively invested in the exploitation and production of metals and rare earth. © BRGM
Should we reopen mines in Europe ?
According to Nicholas Arndt, who worked with Olivier Vidal*, the idea is not so absurd. « We closed all mines because that industry was considered outmoded, underlines the professor of ISTerre. The outcome is that today, there is no exploration and no attempt to find new deposits. » Will we reopen mines in France ? About fifteen requests for research permits for metals such as copper, zinc or lead have been submitted to the government and three permits have already been granted in the regions of la Sarthe, la Creuse and le Maine-et-Loire, in the hope of finding these highly strategic metals. Patricia Cerinsek Translation by Sandra Bailly, Freelance translator EN-FR & Desktop Publishing SpecialistTel : +33 6 95 87 15 27 – email : sandra.bailly79 [at] gmail.com
