Ever since the EU restricted sales of traditional incandescent light bulbs, people have complained about the shortcomings of their energy-efficient replacements. The clinical white beam of LED and fluorescent (CFL) bulbs is not as attractive as the warm glow of traditional filament bulbs, which also show colours far more naturally. In addition, there is evidence that the blue light emitted by modern bulbs could be harmful to our vision. But help is on the way as scientists in the US have come up with a solution which could bring back the old light bulbs by making them extremely efficient.

Traditional light bulbs are only about 5% efficient, with 95% of their energy being lost to the atmosphere as heat. In comparison LED or CFL bulbs manage around 14% efficiency. Researchers at the Massachusetts Institute of Technology have discovered a technique that they call ‘recycling light’ which captures the energy which would usually escape into the air from a traditional bulb, and redirects it back to provide more light. They say that this new bulb can provide efficiency levels of 40% or more. "It recycles the energy that would otherwise be wasted," said Professor Marin Soljacic.

These new bulbs will also be much more economical. The old incandescent bulbs cost about €7 per year to operate, whereas the LED and CFL bulbs cost only €1.50. But if the new bulbs live up to expectations they would not only give a warmer and truer light, but would cost under 50 centimos a year to run.