Light work

A man-made semiconductor used to make light-emitting diodes (LEDs) could reduce household lighting bills by up to 75 per cent within the next five years.

Gallium Nitride (GaN) emits bright light while using minimal electricity. It has been used to illuminate landmarks such as Buckingham Palace and the Severn Bridge, and has also been appearing in camera flashes, mobile phones, torches, bicycle lights and interior transport lighting. However, up until now it has been too expensive to be used in homes and offices.

Funded by the Engineering and Physical Sciences Research Council (EPSRC), the Cambridge University-based Centre for Gallium Nitride has been developing a new way of making GaN.

The centre is growing GaN on silicon wafers, rather than the expensive sapphire wafers that have been used since the 1990s. According to researchers, this brings down the cost of LEDs to a tenth of the current price and cuts the proportion of UK electricity used for lights from 20 per cent to five per cent.