The benefits of an alternative nuclear fuel that could offer a safer and more abundant alternative to uranium that powers conventional reactors have been "overstated", according to a new government report.
It says UK should continue to be engaged with the technology but downplays claims by thorium proponents that the radioactive chemical element makes it impossible to build a bomb from nuclear waste, leaves less hazardous waste than uranium reactors, and runs more efficiently.
"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).Some of NNL's hesitance comes from UK utility companies' unwillingness to invest money in 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 notes that thorium’s advantages would be most noticeable in reactor types other than the conventional solid fuel, water-cooled reactors used in almost all commercial nuclear electricity stations today.
In particular, a design using a very high temperature reactor is "especially well suited to thorium fuels," NNL states. The old UK Atomic Energy Authority built an experimental thorium-fueled high temperature at Winfrith in the 70s. The reactor, nicknamed Dragon, is partially decommissioned.