Light bulbs: LED lights LED lights explained What are LED lights? LED (or light emitting diode) light bulbs have been around for many years, typically used in gadgets such as digital clocks, TV remotes and as Christmas lights - but it has only been relatively recently that the technology has been used to create regular household light bulbs. LED lights have been hailed as the future of home lighting as they use very little energy, are claimed to last a very long time and, unlike regular energy-saving bulbs, they are instantly bright when switched on. But because they have not been widely used for home lighting in the past, they tend to be the most expensive type of energy-saving light bulb and they tend to be available in lower brightnesses. However, the technology behind LED lights is developing quickly so they are now cheaper than they used to be and can be found for anything between £4 and £40. Take a look at our LED light bulbs rated page to see the best and worst LED lights. LED bulbs differ from traditional incandescent bulbs in the way they produce the light. While old fashioned incandescent light bulbs passed electricity through a filament, LEDs produce light through the use of a semi-conductor that emits light energy when an electrical current is passed through it. This way of producing light is also different from regular energy-saver bulbs, which pass energy through mercury vapour to create UV light, which is then absorbed by a phosphor coating inside the lamp causing it to glow. LED light bulbs use 90% less energy than incandescent bulbs
Why should I buy LED light bulbs? There are three types of energy-saving light bulb: compact fluorescent lamps (CFLs - the most common type of light bulb), halogens and LEDs. LEDs are the most expensive, but do have benefits over the other types: LEDs use 90% less energy than incandescents (CFLs use 60%-80% less than incandescents, and halogens use 20-30% less).LEDs are claimed to last for 25-30 years, dependent on use.LEDs give out their light quickly at start-up, so you don't have to put up with a few moments of dim light when you flick the light switch.LED lights don't contain mercury (CFLs do, although it's only a small amount)Our tests have found that LED lights, like halogens, work fine in low temperatures, whereas CFLs don'tAt Which? we've reviewed and rated more than twenty LED light bulbs in brightnesses up to the equivalent of a 60W traditional incandescent bulb. Go to our LED bulbs rated page to discover which light bulbs we recommend as Best Buys, or see all our Best Buy light bulb reviews if you're still considering compact fluorescent lamps (CFLs) or halogen lights. What should I look out for with LED light bulbs? Until recently, LED light bulbs have generally only been available in lower wattages and lumen levels than other types of light bulb. So although they are quick to reach their full brightness and suffer no decrease in performance over time, they are often only available in dimmer varieties than CFL and halogen bulbs. This is improving all the time, however, with brighter LEDs becoming increasingly available. Some people don't like the quality of light given out by LED light bulbs, as they tend to produce a cooler bluish light, so take this into consideration when choosing the best ones for your home. Take a look at our guide to buying energy-saving light bulbs for more information on brightness levels, lumens, light bulb shapes and fittings.