Thorium: in search of a global solution

Last week, an international conference held at CERN brought together the world’s main experts in the field of alternative nuclear technology for the first time to discuss the use of thorium for the production of energy and the destruction of nuclear waste. Among the different technologies presented and discussed at the conference was ADS (Accelerator-Driven Systems) which relies primarily on particle accelerators.

The conference Chair (far left), the organisers and some of the distinguished participants of the ThEC13 conference held at CERN from 27 to 31 October 2013.

“CERN has always been interested in finding ways in which fundamental research can help to resolve the problems of society,” says Jean-Pierre Revol, a physicist at the ALICE experiment who recently retired from CERN and is President of iThEC, the international not-for-profit organisation which promotes research and development in the field of thorium and which organised the Thorium Energy 2013 (ThEC13) conference at the Globe of Science and Innovation from 27 to 31 October. “CERN was the obvious place to hold this conference to take stock of developments in the field of thorium. Carlo Rubbia proposed his Energy Amplifier at CERN and pioneering accelerator technologies are being developed here which could be used for energy production. We can also do simulations of the interactions between beams and matter and finally we have installations such as n_TOF which provide increasingly precise data for these simulations."

Thorium could be an alternative to uranium for the production of nuclear energy. Its fission processes produce less radioactive waste, it is so abundant on Earth that there is enough to sustain human energy needs almost indefinitely, and its use in an ADS poses far fewer risks than in uranium reactors. The conference provided the global community of scientists and experts in the field with an opportunity to discuss thorium as a potential solution to the problem of energy supply. In terms of the technology, at a global level there are two schools of thought: those who favour the construction of power plants using thorium in critical molten salt reactors and those who think that the best way to use thorium is in accelerator-driven systems. “This idea was put forward by Professor Carlo Rubbia at CERN about 20 years ago,” explains Jean-Pierre Revol. "It involves the use of a proton accelerator to drive a nuclear reactor. There is a lot of development still to be done, but the basic technologies of ADS are in principle known and understood.” 

At the ThEC13 conference, both of these schools of thought were represented. Their advocates were able to discuss the general situation, exchange viewpoints and compare different prospects and technological challenges. “The dialogue was sometimes quite animated but always very constructive," says Jean-Pierre Revol. “It even continued after the conference on several levels, for example between the experts in a particular technology regarding the internal components of the system: such as whether the accelerator should be a linac or a cyclotron.” 

Numerous synergies arose from the ThEC13 conference. “For example, the Chinese scientists were particularly interested in the n_TOF facility, which could allow them to improve the precision of their calculations," says Jean-Pierre Revol.

India and China are two important players in thorium R&D, with India being the furthest advanced. These two countries need to increase their energy production dramatically and in a short space of time. Producing the energy they need with fossil fuels would result in a dramatic increase in the amount of CO₂ produced and in chemical pollution globally. The thorium solution therefore merits serious study. “We don’t claim to know it all and we can't yet say what the ideal solution will be," concludes Jean-Pierre Revol. “The value of a conference like ThEC13 is to facilitate exchanges between the different countries facing the same problem. Our aim is to promote research and development in a field which has a real potential to succeed, just as CERN has been doing for a long time in the field of particle physics.”

by Antonella Del Rosso