For energy saving advice and support
in the Bristol and Somerset area:
0800 082 2234

Lighting

Energy-saving light bulbs use up to 90% less electricity than the old bulbs but produce the same amount of light. And they last over 10 times longer.

Since 2011, all light bulbs in the EU have been required to meet new energy efficiency standards. Because of the phasing out of inefficient old-style bulbs and replacing them with energy efficient alternatives, a typical UK home now uses nearly a third less electricity to light their home than it did in the late 1990s.

After 2016, only light bulbs with an energy rating of B or better will be available to purchase. A typical old-style (incandescent) bulb would have an energy rating of E.

Like the old-style bulbs, energy saving ones come in a range of shapes, sizes and brightness. You can buy them for bayonet or screw fittings. Even dimmable low-energy bulbs have been developed. What’s more, the most recent models have a warmer light that’s very similar to old-style bulbs.

There are now three main types of low-energy light bulb: halogen bulbs, compact fluorescent light bulbs (CFLs) and light emitting diodes (LEDs). All of these bulbs are more efficient and last longer than their old-fashioned equivalents. They produce more light for each unit of electricity and they need to be replaced far less frequently.

Halogen bulbs

These bulbs work in a similar way to old-style incandescent bulbs, have a similar light quality, but use up to 40% less electricity. They work well with dimmer switches and reach full brightness almost instantly. However, rooms lit by halogens usually have lots of fittings which increases the overall cost of lighting. Unfortunately, halogens still use considerably more energy than LEDs or CFLs and do not meet the B rating standard for energy efficiency, so the EU has set a target date of 2016 for phasing them out. You can replace your halogen bulbs with LEDs.

CFLs

Compact fluorescent light bulbs or CFLs are the most common type of light bulb sold in the UK. They use the same technology as fluorescent tube lamps found in offices and commercial buildings. They often look like tubes shaped into a helix or a series of loops, though it is now possible to get CFLs in a range of traditional bulb shapes. There are also bulbs available which mimic the light quality of incandescents. CFLs are often criticised for taking a long time to reach full brightness, but most now reach 70% of full brightness within a minute of being turned on.

LEDs

Light emitting diodes, usually referred to as LEDs, are the most efficient bulbs available. They’ve been around for years as little lights on TVs and as bicycle lights. They achieve full brightness instantly, can be dimmed and come in a wide range of colours, including hues close to traditional incandescent bulbs.

LEDs are more expensive but their extremely low energy consumption means that this cost is more than repaid over their very long lifetime. They use a tenth of the electricity of the equivalent halogen bulbs. LEDs are a low energy option for modern fittings like G4 and MR16 as well as being available for more traditional fittings like bayonet, screw and strip lights.

How do they compare?

 Halogen bulbsCFL bulbsLED bulbs
Rough cost per bulb£2£4£10
Typical energy saved*25%75%80%
Average lifespan (hours)2,00010,00025,000+
Time to reach full brightnessInstant30-120 secsInstant
Typical running cost per year£12.32£4.11£3.29

*compared to an equivalent old-style incandescent bulb

Watts and lumens

Light bulbs have traditionally been rated in watts. The wattage tells you how much electricity a light bulb will use and enables you to work out how much it will cost to run. The amount of light given off is measured in lumens. These days, when you buy a light bulb you will see a figure for lumens as well as the wattage rating on the packaging.

The table below shows the wattage you’d need to produce the same brightness with different types of bulbs. You can use it as a guide to converting your old bulbs to more energy efficient equivalents. For instance, you could replace a 100 watt old-style bulb with a 20 watt LED bulb and get the same amount of light (using much less electricity).

Lumens (brightness)Old-style bulbHalogen bulbCFL bulbLED bulb
1300100W75W25W20W
70060W45W15W12W
40040W30W10W8W
20025W19W6W5W

Turn them off!

Finally, if you’re worried about your electricity bill, one of the best things you can do is keep an eye on your household’s use of lighting. Are lights switched off when they’re not needed or are they being left on in unoccupied rooms? What about passageways and landings? Do you really need those lights on all the time? It is particularly important to use low-energy bulbs in places where you really do need to have the light on for long periods of time.

Image: LED bulb, Tom Raftery | reproduced under a Creative Commons license

Frequently asked questions

Don't energy saving light bulbs take a long time to light up to full brightness?

Many years ago this would have been the case. However modern low energy light bulbs get up to full brightness very quickly. LED light bulbs are also becoming more popular. These are extremely efficient and light up instantly.


Need more help?

We can advise you about saving energy, or help you understand what grants and support you're eligible for:

Contact us Or freephone: 0800 082 2234


Next question

View all frequently asked questions

Are low energy light bulbs as bright as the equivalent tungsten light bulbs?

Low energy bulbs come in a range of wattages. It will tell you on the box what the equivalent old-fashioned bulb would be for low energy bulb you are buying.


Need more help?

We can advise you about saving energy, or help you understand what grants and support you're eligible for:

Contact us Or freephone: 0800 082 2234


Next question

View all frequently asked questions

Are there low energy light bulbs for all types of fitting?

Gone are the days when an energy saving light bulb had to stick out of the top of your lampshade. Low energy light bulbs are now available to fit the majority of fittings and come in a variety of shapes and sizes.


Need more help?

We can advise you about saving energy, or help you understand what grants and support you're eligible for:

Contact us Or freephone: 0800 082 2234


Next question

View all frequently asked questions

Need more help?

We can advise you about saving energy, or help you understand what grants and support you're eligible for:

Contact us

Need advice about saving energy? Want help with grants and support?

Send us a message and one of the team will get back to you as soon as we can*:

Data Protection: I understand the information supplied on this form will be stored by the Centre for Sustainable Energy. I understand that I may be contacted by the Centre for Sustainable Energy for the purpose of giving impartial energy advice. I understand that the Centre for Sustainable Energy will not pass my details on to any third parties.

* We aim to respond to your enquiry within two working days.

Translate this page

 

Download the PDF

Download this PDF document

This information is available as a freely downloadable PDF from this page.

For more domestic energy advice, view all our advice pages.