Buying energy efficient products

Lighting

The evolution of light bulbs
Phasing out inefficient light bulbs
Potential savings when switching halogen bulbs for LEDs
How do I choose the right light bulb for my needs?
What else can I do to reduce my lighting bill?

Benefits

Lower your carbon footprint
Reduce your lighting bills
Make your home light and bright

Energy efficient lighting helps lower electricity bills and carbon dioxide emissions, all without reducing the quality of light in our homes.

If you replace all the bulbs in your home with LED lights, you could reduce your annual carbon dioxide emissions by up to 35kg in Great Britain (GB) and 35kg in Northern Ireland (NI).

Lighting makes up 11% of the average UK household electricity consumption, so making the switch could help you save money too.

This guide explores what lighting solution is right for you.

The evolution of light bulbs

Traditional or incandescent light bulbs were invented more than 100 years ago and are extremely inefficient. Only about 5% of the electricity they use converts into visible light. What’s more, the bulbs don’t last long because the filament that creates the light evaporates as heat passes through it.

Halogen light bulbs use the same filament technology as traditional bulbs but run at a higher temperature, making them slightly more efficient. They are mainly used in spotlight fittings. Traditional incandescent and the least efficient halogen light bulbs are being taken off the market in favour of energy efficient alternatives. Instead of these energy inefficient designs, we can use modern replacements to provide the same amount of light, but for less electricity.

Compact fluorescent lamps (CFLs) were the first energy efficient bulbs on the market and use around 70-80% less electricity than the equivalent traditional bulbs, as well as lasting almost 10 times longer. CFL bulbs have a gas inside a glass tube that is charged with electricity until it glows.

Light emitting diodes (LEDs) have largely replaced CFLs, which are more efficient still, turn on instantly at full brightness, and are available to fit pretty much any light fitting in the home. LEDs produce light from the electricity flowing through them. Within a bulb, you will find a large number of LEDs to create sufficient brightness.

Strip lights or linear fluorescent lamps (LFLs) are more often found in offices or industrial settings. Modern strip lights are more efficient, faster to light up and emit a better quality of light than traditional strip lights.

Phasing out inefficient light bulbs

Companies are not allowed to manufacture new inefficient halogen lights, but shops are allowed to sell their old stock, and specialist halogen bulbs are still found in ovens, cooker hoods and security lights.

This means when shopping for new products and replacement lights, you should check the labels carefully and try to buy energy-efficient alternatives to halogen lights.

Potential savings when switching halogen bulbs for LEDs

How do I choose the right light bulb for my needs?

Select the right bulb

There are two main types of energy-efficient light bulbs available: compact fluorescent lamps (CFLs) and light emitting diodes (LEDs).

LEDs are the most common and adaptable light fitting, and are suitable for replacing dimmable lights and spotlights. LEDs are also more energy-efficient than CFLs.

If you replace all the bulbs in your home with LED lights, you could save £40 a year in GB and £50 in NI on your electricity bills.

This table shows the best type of bulb to use in different environments.

General lighting	LED or CFL
Outdoor	LED or CFL
Spotlighting	LED spots
Dimmable lighting	LED or B-rated halogen
Crystal chandelier	LED

Select the right lumen value

If you have ever bought a low energy light bulb and been disappointed by the level of brightness it gives out; you may have picked a bulb with too small a lumen value.

With traditional bulbs, we used watts to determine the brightness of a bulb, but watts measure power consumption rather than brightness. Energy-efficient bulbs use fewer watts, so it is best to look at lumen output.

This table compares the wattage of traditional bulbs and approximate equivalent lumen values of LEDs / CFLs.

Traditional bulb	LED / CFL bulb
15 watt	140 lumen
25 watt	250 lumen
40 watt	470 lumen
60 watt	800 lumen
75 watt	1,050 lumen
100 watt	1,520 lumen

Select the right colour

Low energy light bulbs imitate traditional light bulbs, so if you prefer a particular colour, there should be a close match with the new energy-efficient lighting.

‘Soft white’ or ‘warm white’ bulbs provide a cosy glow that is best for general household lighting, while ‘cool white’ or ‘pure white’ are ideal for office spaces or any area that requires clear vision.

The colour rendering index (CRI) of a bulb shows you how well a bulb will illuminate a chosen colour. Two bulbs can have the same colour, but the bulb with a higher CRI will show colours more accurately than the other.

The bulb’s packaging will indicate the CRI alongside the lumen value. A CRI of 80 or more is appropriate for most household tasks.

What else can I do to reduce my lighting bill?

Always turn lights off when leaving a room. The quickest way to start saving is just remembering to turn lights off when you don’t need them. The typical household could save almost £7 a year in GB and £9 in NI just by switching off the lights as you leave the room.
Be aware of how many lights you have on in a room. If you have the main light on, do you need the lamp on too?
Arrange light switches so it is easy to turn them off, for example, place switches for rooms at the door.
Use sensors or timers on external lights, so they are only on when they need to be.
Consider using transparent shades or fittings, as a dark lampshade can absorb some of the light a bulb emits.
Ensure that you regularly clean any lamp shades or fittings to increase the impact of the light.