It takes a lot of copper to plug in an offshore wind turbine – around 8,000kg per megawatt (MW). Analysis by the International Energy Agency (IEA) suggests the wind industry is the most copper-intensive renewable power technology sector. An average turbine of 3.6MW, which can power more than 3,300 average EU households, will contain close to 29 tonnes (t) of copper.
The main reason for this heavy use of copper is the cables, which enable electricity from the turbines to be transmitted to the power grid.
As the roll-out of wind power increases and turbines get bigger, demand for copper will also shoot up. For reference, today’s global offshore wind capacity stands at 34GW. This figure is expected to pass 230GW by 2030, says the Global Wind Energy Council, a staggering increase of at least 570% in ten years. At the same time, as of May 2021, the copper price soared to an all-time high of $10,440/t (€8,607.82).
Whether there is enough copper to go round for all industries remains to be seen, but Energy Monitor’s weekly data shows how consultant KPMG believes clean energy production will only have used 2% of global copper assets by mid-century compared with known reserves in 2020.
Reacting to the IEA report, Kingsmill Bond, energy strategist for Carbon Tracker, a UK think tank, accepts the mineral assets needed to build renewable technologies are higher than those required for fossil fuels.
However, he believes this is a narrow way of looking at the issue. “They [IEA analysts] look only at the stocks (the assets you need to build the generator or car) not the flows (the energy you need to run them),” he writes.
In addition, the demand for critical minerals that would be needed to build out the amount of renewable energy to keep global warming below 1.5°C is still 300 times less than current demand for fossil fuels mined out of the earth, says Bond. Put simply, the advantages of renewable energy outweigh by far the disadvantages that come with mining the minerals and rare earths needed to produce it, he argues.