Does thorium have the answer to our energy needs?
As we move to a low-carbon economy, generating sufficient carbon-free energy to make the use of fossil fuels a true thing of the past is a huge challenge. Nuclear is often touted as the most viable large scale source of low carbon electricity to support other sources dependant on the weather, such as wind or solar energy. But as Fukushima showed, nuclear power stations can present real risks.
However, there’s a growing community that believes that swapping from uranium – which has to be enriched before it can be used to make nuclear fuel, creating dangerous by-products such as plutonium – to a more abundant mineral called thorium, could provide the answer.
Thorium has a far higher melting point than uranium, so making nuclear meltdown disasters of the kind experienced at Chernobyl and Fukushima less likely. It also produces less radioactive waste. And as former UN Weapons Inspector Hans Blix is keen to point out, thorium’s lack of enrichment means it has no by-products from which nuclear weapons can be made.
In addition to being safer, it is also more cost effective – one tonne of thorium is estimated to produce as much energy as 200 tonnes of uranium or 3.5 million tonnes of coal. As Labour peer Baroness Worthington, the architect of the UK’s climate change legislation, says: “It’s a fuel no one has heard of, that everyone needs to hear of.”
First the fuel, then the reactor
So what’s the catch? The use of thorium still has to be proven on a commercial scale. Sadly, it’s not a question of simply switching one fuel for the other. To develop a new generation of thorium-powered nuclear reactors is likely to require huge investment and long timescales.
That said, a test programme in Norway is currently looking at adapting traditional water-cooled reactor plant to utilise thorium. India is also working on a project to convert an existing uranium-powered reactor to run on thorium.
Meanwhile, China is building a new generation molten salt reactor – a prototype of which was successfully developed in America in the 1960s. And research projects are also underway in countries as diverse as France, Australia and Brazil, with interest being shown by many other nations including Britain.
30% of electricity by 2050
As for the potential of thorium once the reactor technology is developed, claims are bold. India, for example – which sits on sizeable share of the world’s thorium reserves – has said it envisages meeting 30% of its electricity demand from thorium-powered reactors by 2050.
The US could also benefit. According to the Washington-based Thorium Energy Alliance, “there is enough thorium in the United States alone to power the country at its current energy level for over 10,000 years.”
But as with all things energy related, don’t expect the status quo to change any time soon. New developments take time – and if it involves nuclear technology, that’s likely to mean even longer…