After more than 50 years of experimentation, physicists are hoping to develop the first form of nuclear fusion technology that produces more energy than it consumes. Within the next fortnight, researchers at the National Ignition Facility (NIF) in California will fire 192 separate laser beams capable of generating 500 trillion watts - 1,000 times the power of the US national grid - for a fraction of a second. Scientist are to use the world’s most powerful laser system to replicate the fiery core of the sun in experiments that may ultimately offer humanity a clean source of energy. The energy pulse will be concentrated on a tiny pellet of hydrogen in an attempt to mimic the reactions that take place inside the sun. The scientists hope to refine the process over the next year until they trigger a nuclear reaction capable of producing large amounts of energy. The fusion process mimics reactions that take place inside the sun. Unlike nuclear fission reactions - in which atoms are split apart - the fusion process squeezes atoms together under enormous pressures and temperatures until they fuse, releasing huge quantities of energy. Even if scientists are able to tame fusion reactions, most experts believe we would still be at least 25 years away from being able to build fusion power stations that could provide a clean alternative to fossil fuels. “We hope the ignition experiments will show that we can generate more power than we put in and that fusion can be the source of a supply of carbon-free energy,” said Ed Moses, director of the NIF. “I think the old joke about fusion being just 50 years away, no matter when you ask, is about to become defunct. If we succeed, public perception of fusion will change because it is the ultimate energy source - no carbon, limitless, safe and secure.” In France, work has begun on building the £8 billion Iter fusion project, which uses magnetic fields rather than lasers to create the conditions for fusion. However, Iter’s first “burn”, or reaction, is not expected until 2022. A British-led fusion project, the high power laser programme (HiPER), is expected to build a reactor at the Rutherford Appleton Laboratory (RAL) in Oxfordshire by 2020. Source: The Times