Believe it or not, British traffic lights consume the energy equivalent of two medium-sized power stations every year.

Furthermore, their bulbs are replaced every six months by teams of electricians working in the small hours when cars are less numerous.

New light bulb technology based on gallium nitride will soon transform this situation, and lead the way for longer lasting, lower wattage domestic bulbs as well. The gallium nitride bulbs last for at least ten years and only consume 20% of the electricity consumed by conventional tungsten-halogen traffic lights.