The largest and most expensive scientific experiment since the international space station has been given the green light.

A consortium of international ministers has agreed to back construction of ITER (International Thermonuclear Experimental Reactor) in the South of France. Representatives say the aim is to develop a prototype fusion power plant, based on the process which powers the stars. It is hoped the project will help solve the world’s energy needs, which are expected to increase by 60% over 20 years at the time when the issue of global warming is becoming critical. A 1GW fusion power station would burn about 1kg of deuterium and tritium per day, compared with a 1GW coal power station burning 10,000 tonnes per day of coal. The construction costs are estimated at 5 billion Euros over ten years.