BRITAIN has joined forces with America to investigate a hi-tech new way of producing 'clean energy - not from wind or waves, but from firing huge arrays of high-powered lasers at pellets of hydrogen. The process causes the hydrogen atoms to fuse together into helium - the same reaction found in hydrogen bombs and stars such as our Sun - but in a controlled reaction that could power homes and businesses. Recent experiments at Americas National Ignition Facility (NIF), have produced huge bursts of energy from the technology - using a stadium-sized building housing an array of 192 lasers which fire a 500-terawatt flash at a drop of hydrogen atoms just 1mm across. For the instant during which NIFs laser is fired, it uses more power than the electricity consumption of the whole of America. But the returns are increasing. In an experiment this week, a burst of power was released from the fusion reaction that was equivalent to the entire worlds consumption. The UK company AWE and the Rutherford Appleton Laboratory have now formally joined forces with the American facility, in a meeting at Londons Royal Society. 'This is an absolutely classic example of the connections between really high-grade theoretical scientific research and a fundamental human need: our energy supply, said David Willets, the UKs science minister. 'Controlled nuclear fusion - the reaction in a hydrogen bomb is uncontrolled - is a Holy Grail of clean energy that scientists have sought to crack since the Fifties. Recent breakthroughs in America have drawn closer to the technologys final aim - a reaction that produces more energy than is put in to achieve it. DM Previous UK approaches to nuclear fusion have focused on a different technology - magnetic containment fusion, in which a doughnut-shaped 'torus houses a stream of circling atoms heated by huge towers firing particle beams to many times the temperature at the centre of the sun. The huge JET (Joint European Torus) facility outside Oxford has achieved reactions which release energy, but has never achieved 'break even - the point at which the amount of energy released by the fusion reaction is equal to the energy put in. But magnetic containment fusion is extremely expensive - a new reactor planned for Europe was budgeted to cost more than the Large Hadron Collider, and could be the most expensive science project since the International Space Station. DM