Published on September 14th, 2012 | by Nathan73
Benefits of Thorium Are ‘Overstated’, UK Report Finds
Thorium nuclear has often been argued for as a solution to the world’s energy problems. It’s proponents say that it is safer and cheaper than the uranium that powers normal nuclear reactors. However, a newly released government report in the UK says that the supposed benefits of thorium are “overstated.” (Coincidentally, we’ve had some pretty active discussions this week on two CleanTechnica posts regarding thorium.)
The new UK report suggests that the UK continues to be involved with the technology, but that many of the claims made by thorium proponents are exaggerated. Specifically, the claims that it is impossible to build a bomb with the nuclear waste from thorium, that it doesn’t leaves toxic waste, and that it is more efficient, are singled out as overemphasized.
“Thorium has theoretical advantages regarding sustainability, reducing radiotoxicity and reducing proliferation risk,” states the report, prepared for the Department of Energy and Climate Change by the National Nuclear Laboratory (NNL). “While there is some justification for these benefits, they are often overstated.”
Part of the reason that the NNL is ‘pessimistic’ about the technology comes from the fact that UK utility companies are not willing to invest the money into the research and development necessary to “draw out thorium’s advantages.”
“Nevertheless, it is important to recognise that worldwide there remains interest in thorium fuel cycles and this is not likely to diminish in the near future,” the report concludes. “It may therefore be judicious for the UK to maintain a low level of engagement in thorium fuel cycle research and development by involvement in international collaborative research activities.”
The report also makes a note of the fact that thorium’s possible advantages over conventional nuclear would only be clear when used in reactor types other than the conventional solid-fuel, water-cooled reactors that are used in nearly all of the world’s commercial nuclear electricity stations.
“In particular, a design known as a very high temperature reactor is ‘especially well suited to thorium fuels,’ NNL states. The old UK Atomic Energy Authority built and operated an experimental thorium-fueled high temperature at Winfrith in the 1960s and 70s. The reactor, nicknamed Dragon, is partially decommissioned.”
There are several other projects underway outside of the UK. In America, Flibe Energy is creating a thorium reactor that is based on designs developed in the 1960s by the US Department of Energy’s Oak Ridge National Laboratory in Tennessee.
In Asia, China and India are both developing the technology. The latter is likely to begin construction on one that uses solid thorium fuel in the next four or five years.
“Thorium is an abundant, mildly radioactive element that occurs naturally around the world. The largest reserves exist in Australia, the US, Turkey, India, Brazil and Venezuela, according to the World Nuclear Association.”
In summary, in solid-fuel, water-cooled reactors thorium nuclear reactors (which some countries are working on) still produce a waste product that lasts an extremely long time and is very toxic; are an an easy terrorist target or source of bomb-making ingredients; and don’t seem economically efficient to develop.
High-temperature, liquid-fuel nuclear reactors may solve the problems above, but they have not been tested nearly as much, and there has never been commercialization of such a reactor.
Other unstated downfalls of at least some (if not all) thorium reactors include: extreme susceptibility to disasters, including droughts; and truly unknown longterm effects on life via the regular releases of very small quantities of radioactive elements.
The full National Nuclear Laboratory report can be accessed on the UK’s Department of Climate Change & Energy website.