Leading lights

Research on gallium nitride (GaN) by the Cambridge Centre for GaN has revealed that by growing GaN on silicon instead of sapphire wafers, leds can be mass produced at a 10th of the current price. On this basis, if GaN led lights were fitted in every building in the UK, within five years the proportion of UK electricity used for lighting would reduce from 20% to 5% - the equivalent of eigh power stations. Further applications include camera flashes, mobile phones and automotive lighting, while ultraviolet rays could even help water purification in third world countries. Lead scientist Prof Colin Humphreys, pictured, said: “This could well be the holy grail in terms of providing our lighting needs for the future. We are very close to achieving highly efficient, low cost white leds that can take the place of both traditional and currently available low energy light bulbs. That won’t just be good news for the environment. It will also benefit consumers by cutting their electricity bills.” GaN leds can burn for 100,000 hours and do not contain mercury, so disposal causes less damage to the environment.