Many environmentalists are sure that renewable energy would save the planet from disaster. Just yesterday I heard from Science Club on BBC that we should deploy giant solar panels in order to capture all the energy we need from the Sun and say goodbye to pollution, global warming and well drillings throughout the Earth.
So, let’s do a simple exercise: consider a scenario in which electric cars finally take over the ones with a combustion engine. Nowadays the only model that better approximates our idea of “green car” produced on a large scale is Toyota Prius, an hybrid electric vehicle which uses Ni-MH (nickel-metal hydride) battery packs. This “metal” is lanthanum, and the quantity that equips every Toyota Prius amounts at least to 10 pounds (4.53 kg). Lanthanum belongs to the rare earth elements group, which is actually of fundamental relevance for hi-technology (from computers to wind turbines, from headphones to cordless drills, passing through hybrid cars).
In 2012 approximately 500 thousands of Toyota Prius liftback were sold throughout the world – this means that at least 2,265 tonnes of lanthanum were used to manufacture these vehicles. If tomorrow Toyota decides to switch its entire production of cars to hybrid models – 9.9 millions last year – it would need about 44,800 tonnes of lanthanum per year.
Actual lanthanum worldwide production is around 12,500 tonnes per year – so the demand for this metal would become overwhelming: new extraction sites should be found, new mines should be opened.
As I said, rare earth elements are fundamental for hi-tech devices, and for green technologies too. Their production is in many cases limited, and in some cases (neodymium, yttrium) we already can define “critical” on the short term their supplying. This leads to obvious geopolitical considerations, by the way.
In conclusion, I fear that the environmentalist revolution may reveal itself as the same old business cloaked in a new ethical justification. Of course, I’m not denying the benefits (especially regarding global warming and the greenhouse effect), I’m just trying to say that the disadvantages and impacts of specific “green” proposals are largely underestimated in the public debate.
What do you think about?
Sources
About lanthanum and its uses:
- http://www.mmta.co.uk/metals/La
- http://www.popularmechanics.com/technology/engineering/news/important-rare-earth-elements#slide-1
About Toyota and Toyota Prius
- http://money.cnn.com/2012/12/26/news/companies/toyota-gm/index.html
- http://en.wikipedia.org/wiki/Toyota_Prius
About rare earth elements