Plans to develop the most advanced nuclear fusion reactor to date were signed off by officials from the EU, the US, Russia and four Asian nations on Wednesday.

The International Thermonuclear Experimental Reactor (ITER) will be built in Cadarache, in southern France. The entire project is worth about €10 billion ($13 billion) and is expect to run for 30 years. "This is a truly crucial moment, for the ITER project and for global scientific co-operation in general," EU Science and Research Commissioner Janez Potocnik said at the signing ceremony.

Unlike nuclear fission, which involves splitting the nucleus of atoms, nuclear fusion entails squeezing atomic nuclei together. ITER will fuse together two hydrogen isotopes – deuterium and tritium – to generate energy along with helium and neutrons.

This will involve heating hydrogen plasma to more than 100 million degrees Celsius and keeping it contained within a doughnut-shaped magnetic field.

Experimental reactors
Fusion energy has the potential to solve many of the world`s energy problems. In theory at least, it could produce vast quantities of energy using relatively small amounts of fuel. It should also produce far less radioactive waste than a conventional nuclear power station and there should be little risk of a catastrophic accident if a fusion reactor fails as it should simply shutdown rather than experiencing a meltdown.

However, starting a fusion reaction is extremely difficult and requires huge amounts of energy, as discovered by a smaller experimental fusion reactor – the Joint European Torus (JET), in Oxford UK. That reactor has been in operation since 1983, and can only generate about 70% of the energy that is consumed when it is started up. For this reason, some scientists believe fusion will never become a viable energy solution.

This view was reinforced in an article published in Science in March 2006. William Parkins, a veteran of the Manhattan Project and the chief scientist of US engineering firm Rockwell International, claimed many key engineering problems surrounding nuclear fusion remain unsolved.

Important message
But in putting pen to paper in Brussels, the officials, including representatives from Japan, China, South Korea and India, successfully concluded years of talks on one of the world`s most ambitious scientific ventures. Construction of ITER is expected to start in 2008 and will take about a decade to complete, according to project director general Kaname Ikeda.

"Together we are forging a new model for large-scale global scientific and technical co-operation," Potocnik added. "We are sending an important message about seeing the value in working together to address our common challenges."

The EU will provide about 40% of the building costs, with most of the other partners contributing about 10%. The EU will also assume most of the total running costs, about 26% of the €5 billion needed. Negotiations over the prestigious project began in June 2002 and took three years to complete. The original partners were split over whether the reactor should be hosted in Japan or Europe.
(by Will Knight and AFP, NewScientist, 24/05/2006)
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