Humankind could be about to exchange one kind of energy crisis for another. The switch from the finite store of fossil fuels to renewable sources could involve a huge additional demand for the world’s equally finite store of metals and minerals.
Three French CRNS scientists – Olivier Vidal and Nicholas Arndt of the University of Grenoble and Bruno Goffé of Aix-Marseille University said that to match the power generated by fossil fuels or nuclear power stations, the construction of solar energy farms and wind turbines will gobble up 15 times more concrete, 90 times more aluminium and 50 times more iron, copper and glass. Right now wind and solar energy meet only about 1% of global demand; hydroelectricity meets about 7%.
The trio argue that if the contribution from wind turbines and solar energy to global energy production is to rise from the current 400 terawatt hours to 12,000 Twh in 2035, and 25,000 Twh in 2050, that will require 3,200 million tonnes of steel, 310 million tonnes of aluminium and 40 million tonnes of copper to construct state-of-the-art generating systems.
In addition to the already accelerating demand for all kinds of metals, this data would mean an annual increase in global production of these metals of a 13% in the next 40 years.
Right now 10% of the world’s energy budget is spent in digging up and processing mineral resources. This percentage will continue to increase as high quality ores become harder to find, and more difficult to extract.
For example, this presents problems for Europe; right now this consumes more than 20% of the metals mined globally, but European mines produce only 1.5% of iron and aluminium, and 6% of the world’s copper.
“Humanity faces a tremendous challenge to make more rational use of the Earth’s non-renewable raw materials,” they conclude. “The energy transition to renewables can only work if all the resources are managed simultaneously, as part of a global, integral whole.”
Metals and minerals are not in short supply, but their uneven distribution is likely to create political problems, and the competition for supplies already presents ethical problems, both from environmental and humanitarian points of view.
Platinum for instance is vital for catalytic converters and fuel cell technologies: 80% of the planet’s supply comes from just two mines in South Africa. More than 30% of the world’s copper comes from Chile. The world’s largest zinc mine is in the Alaskan Arctic wilderness, and shipments can only be delivered between July and October, because of the sea ice.
The political risks inherent in this uneven spread of mineral riches, he reasons, were clearly demonstrated during the oil crisis of the 1970s, when Middle East oil prices went up, and western economies went plunging down. So he too argues that there should be more attention to local mineral sources, including those in Europe.
“We must acknowledge and control the complexity of giant mining projects with their demands on infrastructure and environment. We need to work hard to understand any ethical issues with the provenance of new resources.
“Better ways of recycling valuable metals from discarded electronic equipment are required,” he argues. “And geoscientists need to undertake a thorough audit of the natural occurrences of mineral deposits that will feed our economies.”
World energy outlook 2012: Renewable energy outlook (International Energy Agency 2012); http://www.worldenergyoutlook.org/publications/weo-2012
Deciding the Future: Energy Policy Scenarios to 2050 (World Energy Council 2007); http://go.nature.com/vYzp4M
Meadows, D. H., Meadows, D. L., Randers, J. & Behrens, W. W. The Limits to Growth: A Report for the Club of Rome’s Project on the Predicament of Mankind (Universe Books, 1972); http://www.nature.com/ngeo/journal/v6/n11/full/ngeo1947.html