One hurdle in the transition to a low carbon future is the huge increase in demand for metals associated with renewable energy technologies. By 2050, it is anticipated lithium production will need to have increased by tenfold, cobalt by sixfold and silver by half as much again. Even the most efficient recycling system cannot meet this demand, and conventional mining practices are energy-intensive and environmentally damaging.
Some mining companies are looking to the deep sea, but as well as being technically challenging, this risks irreversible damage to unique ocean environments. Writing in Geoscientist, Olivia Hogg and Jon Blundy suggest harnessing the power of volcanoes instead. Volcanic magmas are rich in metals, with active volcanoes such as Mount Etna in Italy releasing about 20 tonnes of copper and 10kg of gold a day in volcanic gases. Extracting metals from volcanic gas is implausible, but mining it from the underlying hot magmatic brines does have real potential. Metals are super-concentrated in these brines and the hot fluids could be used to produce geothermal power, potentially making the mining process carbon neutral.
Many challenges remain, but the good news is about 2,000 volcanoes globally have the potential to become brine metal mines. And at least 15 European states have active or dormant volcanoes that might be suitable for metal extraction and geothermal power.
