Thursday 25 March 2010

Areva plans new reactors that make nuclear waste disappear

business.timesonline.co.uk
March 22, 2010

A new type of nuclear reactor that could permanently "destroy" atomic waste is being developed by French scientists, according to the chief executive of Areva, the world's largest nuclear energy company. Anne Lauvergeon told The Times that the French group was developing a technology to burn up actinides - highly radioactive uranium isotopes that are the waste products of nuclear fission inside a reactor. The technology could be critical in winning greater global public support for nuclear energy and cutting emissions of CO2.

"We have developed the highest safety level with [our existing reactors]," she said. "In terms of public acceptance, the remaining issue is the waste. In the future we will be able to destroy the actinides by making them disappear in a special reactor. We can do it already in a laboratory. With research and development, we will address this issue."

The project at Areva is similar to research being carried out at the University of Texas in Austin, where scientists have designed a system that would use fusion to eliminate virtually all the waste produced by civil nuclear reactors. Swadesh Mahajan, senior research scientist at Austin's Institute for Fusion Studies (IFS), believes that the invention could hugely reduce the need for geological repositories for waste. "We want to make nuclear energy as socially and environmentally acceptable as possible," he said. "Nuclear waste cannot be 100 per cent eliminated, but the volume, the toxicity and the biohazard could be reduced by 99 per cent."

The invention could mean, he said, that instead of the world needing to build 100 geological stores for nuclear waste, only one or two might be necessary to store decades of waste. Mike Kotschenreuther, also of the IFS, said that the technology rested on the use of a spherical hybrid fusion-fission reactor. The waste would be held in a "blanket" around the reactor core and destroyed by firing streams of neutrons at it. He acknowledged that big technical challenges remained, not least that to work effectively the reactor would have to operate continuously, creating the problem of how to extract the destroyed waste.

About 440 nuclear plants are operating in 31 countries worldwide, with a collective generating capacity of 370 GWs of electrical power, or 15 per cent of the global total. But electricity produced from nuclear fission also produces 12,000 tonnes of high-level radioactive waste per year, including plutonium that can be used to manufacture weapons.

Ms Lauvergeon said that the volume of high-level nuclear waste produced by all of France's 58 reactors over the past 40 years could fit in one Olympic-size swimming pool. "Of course, it would be better to have nothing, but this is fully managed and we have to view this issue in a balanced way compared to other solutions." Nuclear power produces more than 80 per cent of French electricity. Britain's high-level waste is stored in a temporary facility at the Sellafield nuclear waste plant in Cumbria. The concept of a hybrid fission-fusion reactor was first developed in the 1950s, but little research was conducted for several decades.

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