Gareth Mitchell asks if nuclear fusion could at last be close to generating energy. Nuclear fusion is the holy grail of alternative energy. It is clean, green and could supply limitless energy to the world, but despite decades of research in some of the most expensive science facilities in the world, it has remained an elusive goal. Scientists working at a new experimental facility in California are set to use giant laser beams to try and initiate nuclear fusion. If nuclear fusion could be made to work commercially, the energy released will be of stellar proportions; this, after all, is the process that powers the Sun. The total energy that could ever be created using wind, wave and solar power is ridiculously small by comparison. Nuclear power, which is generated by fission not fusion, requires uranium - which will run out - and, of course, generates radioactive waste. Gareth witnesses the start of a new era of nuclear fusion experiments. He also goes to the Joint European Torus facility in Oxfordshire, which has been using a different technique to create nuclear fusion for nearly 30 years. He finds out about ITER, the next big fusion experiment, which is just being built in the south of France.