On average 17% of your electricity bill is lighting. By switching your ten most used light bulbs to LED lighting equivalents, you can save up to 90% of the energy they use. If every household switched their existing light bulbs to LEDs we could save the equivalent electrical output of several power stations and reduce the national carbon footprint! Plus they last up to 25,000 hours! Have you made the switch to LED lighting?
Simply put - they use less energy and save you money
LED lighting has already transformed commercial lighting and is coming to transform our homes, saving vast amounts of energy and resulting in substantially lower household bills. LEDs illuminate instantly, use around 90% less energy than traditional bulbs and have a long life of typically 25,000 hours.
Around 15% of electricity expenditure is on lighting. Changing just one traditional incandescent (standard) 60 watt light bulb, in use for 4 hours a day will save you upwards of £50 on your bill over five years; 10 bulbs = £500. After accounting for bulb and fitting costs it's still over £40 per bulb. A household changing ten bulbs should save at least £350 over five years. And this assumes electricity prices don't increase.
Savings are nearly as much when replacing halogen bulbs, which offer only around 10% improved efficiency compared with a standard bulb; they also use the old fashioned technology of heating up a wire to give off light. For many people convenience is also a factor. LED bulbs last for typically 25,000 hours of use, far exceeding old technology. It makes changing bulbs an infrequent occurrence. This all makes so much sense that the Government is doing its bit by phasing out the sale of incandescent bulbs (nearly complete) with a broad range of halogens due to be phased out shortly.
NB - technical people call light bulbs 'lamps' and light fittings 'luminaires'. We'll stick with the term 'bulb' in this article.
More about LED Bulb Bases
Light bulbs have a range of 'bases', which need to match the light fitting. Most are familiar to us as initials including BC (bayonet cap), ES (Edison screw), GU50 (mains halogen) and MR16 (low voltage halogen). The picture shows the most common types found. LED bulbs use the same bases.
Brightness: Lumens not Watts
We are all familiar with the concept of thinking of light bulb brightness in terms of their wattage. In reality the wattage refers to the power the light bulb consumes rather than the light given off. LEDs use only a fraction of the power to produce the same amount of lights as the old bulbs so it's better to start thinking in terms of lumens, which are a measure of the amount of visible light.
The table below shows the approximate comparison for differing bulb types.
Colour temperature explained
We are used to the light from our household bulbs being a yellowish colour as shown below. This is typically a 'colour temperature' of around 2700 to 3000 degrees Kelvin (K). LEDs are available in a range of colour temperatures but we generally recommend sticking with a colour temperature of around 3000K. A higher figure of 4000K provides a whitish moonlight type colour. 6000K is more like daylight but can seem glaring in the home.
Other things to consider
On the whole the change is easy and is just a question of selecting a suitable LED bulb to replace a standard, candle or globe bulb or GU50 down light. As well as understanding the points above there are few pitfalls to watch out for.
Check what you are buying: Some stores have been selling low cost low wattage LEDs which whilst decorative don't provide enough light to replace bulbs used to illuminate rooms or read by. Use the table above as a guide.
Dimming LEDs: Whilst LEDs can be dimmed most LEDs sold are not dimmable. If you require dimmable LEDs you'll need to purchase LEDs designed to be dimmed AND change the dimmer control for one designed to work with LEDs - most dimmers used with standard bulbs won't work with LEDs. We've also found that the LED bulbs and dimmers have to be matched to ensure successful dimming.
Low Voltage Bulbs: Low voltage halogen bulbs (MR16 fittings) often found in downlighters, can only be switched to LED if a wound transformer is in use. If the fitting is powered by an electronic power supply (typically a small box) then the chances are LED bulbs won't work properly. The best bet is to move away from low voltage downlighters to 230-volt bulbs using GU50 fittings, which don't need a power supply.
Bulbs Sizes: Most standard bulbs can be replaced with an LED. Some LEDs including standard, downlighter and candle bulbs can be larger (usually longer) so if available space for example in a flush light fitting is critical then check the LED size before buying or specify a smaller bulb type.
Sources: 1. DEFRA. 2. 50plus calculations available on request. Assumed cost of electricity is a conservative 13p/kWh - you may be paying more. 3. Lumens/Watts data source European Commission, picture source www.ovoenergy.com.