An international team of scientists aims prove nuclear fusion is the power source of the future

It is just a building site at the moment but an international team of scientists hopes this will be the launch pad for a new, clean, unlimited energy source.

This is the south of France, the home of ITER - formerly the International Thermo-nuclear Experimental Reactor.

Neil Calder is the project's head of Communications.

NEIL CALDER, ITER SAYING:

"it is a game-changer. If this works we will have inexhaustible, unlimited energy for humanity with none of the drawbacks of some of the other current energy sources."

Fusion works by forcing atoms together to release energy.

It is the reaction that is taking place constantly in the sun and occasionally here on earth.

This is a tokamak -- a machine capable of containing a gas heated to more than a million degrees Celsius in a magnetic field.


"The whole point of this project isn't to prove if we can do fusion or not, we already know that. Machines like this and a handful of others around the world have proven that. What we need to know now is can make on of these work for long enough and turn it into a power station."

Gary Johnson is charged with overseeing the design of ITER's tokamak and changing the way we generate power.

GARY JOHNSON, ITER TOKAMAK DEPARTMENT SAYING:

"The high-side is essentially unlimited fuel. You know, we get deuterium out of seawater, essentially, virtually limitless. It is a very clean technology, no greenhouse gases. It is a very safe technology. You put all that together, if we can make this work it is going to be a great option for the very long term, you know, lets say fifty years and as far into the future as we can see."

Nearly 400 scientists and engineers from around the world are involved in project - to find an answer to our increasing energy needs.

They are designing a machine capable of containing a miniature star for up to 50 minutes - the record is currently less than 10.

If they succeed they will have blueprint for the power stations of the future - fuelled by seawater.

GARY JOHNSON, ITER TOKAMAK DEPARTMENT SAYING:

"We know our energy needs are going to continue to go up over the long term. We have to have something that will provide these energy resources for the long term. Fusion is part of the answer we think."

ITER began life at a summit between Presidents Reagan and Gorbachev in 1985 - but what started as a thaw in the Cold War has been spurred by global warming, and the result could benefit us all.

Stuart McDill, Reuters, Provence