October 9, 2008 Nuclear fusion has long been the holy grail of energy production. It is the process going on inside the sun, it is clean, and it has the potential to provide practically limitless power. Up until now nuclear fusion reactions have only been replicated inside hydrogen bombs due to the huge amount of power needed to start the reaction and keep it running, but scientists in Britain are hoping to change all that. Britain’s Telegraph newspaper is reporting that British scientists believe they are on the verge of achieving controlled fusion in a laboratory for the first time and will begin work this week to create a nuclear fusion reactor.

Scientists at the Rutherford Appleton Laboratory, near Oxford, will utilize laser beams with enough power to light up every home in Britain for a few microseconds to heat up the nuclear fuel to millions of degrees centigrade in order to trigger the reaction. If successful, the reactor will be a prototype for future commercial power stations, providing a cleaner and safer replacement for conventional nuclear power stations, which use nuclear fission to produce energy. Unlike nuclear fission, which tears apart atoms to release energy and highly radioactive by-products, fusion involves squeezing two "heavy" hydrogen atoms, called deuterium and tritium together so they fuse, producing harmless helium and vast amounts of energy.

The three year process of planning and designing the High Powered Laser Research (HiPER) facility is not the only project of its kind. Fusion reactors are already under construction in France and the US using two separate approaches to creating the intense pressure and heat required to trigger the nuclear fusion reaction. The International Thermonuclear Experimental Reactor in Cadarache, France, is aiming to use powerful magnetic fields to spark the reaction, while the National Ignition Facility in Livermore, California, is aiming to use powerful lasers to create the intense pressures required to trigger the reaction when it is switched on next year.

It is believed the US approach will prove that fusion can be created using laser technology and provide the first step towards a commercial power station, enabling the HiPER project to adapt the American laser approach and improve its efficiency so that it can trigger the reaction at lower pressure. The researchers, which includes a consortium of physicists from across Europe, have received £13 million for the first phase of the £1 billion project to build the HiPER facility. Most of the funding has come from the UK government funded Science and Technology Facilities Council, together with contributions from the European Commission.

Professor Mike Dunne, director of the central laser facility at the Rutherford Appleton Laboratory and one of the scientists leading the fusion project explained, "If you think of the NIF as being like a diesel engine – the lasers compress the fuel pellet until the pressure causes the fusion reaction to start. HiPER is more like a petrol engine where the fuel is compressed a little by the lasers but then a second more powerful laser acts like a spark plug to trigger the fusion reaction."

Unlike nuclear fission, the fusion reaction produces only produces very small amounts of low-grade radioactive material and does not carry the risk of radioactive meltdown. Fusion fuel, deuterium and tritium is also readily available in seawater. Just 2lbs of fusion fuel is capable of producing the same amount of energy as 10,000 tonnes of fossil fuel. Hopefully all goes well for the researchers and we’re all enjoying guilt free and eco-friendly electricity before too long.

Darren Quick