Energy-saving devices

energy saving devices

This guide is intended to provide general guidance only. It is not intended to give you advice on your personal financial circumstances. You should seek independent professional advice if you’re unsure about anything mentioned in this guide or what choices to make

Using less energy not only reduces your fuel bills, it also cuts down your carbon emissions, which is better for our planet and future generations.

Clearly, the best way to use less energy is to make sure your home and all your electrical appliances are working as efficiently as possible.

However, there are also all kinds of gadgets and energy-saving devices for homes that can help you reduce the amount of energy, heat or water you use – some more useful than others.

Should I be using energy-saving light bulbs?

In most houses, lighting makes up roughly 20% of the electricity bill. Altogether, UK homes spend around £2.3 billion every year on electricity to power their lighting.

Energy-saving light bulbs are one of the best energy-saving devices around. They use up to 80% less electricity than standard bulbs and last around ten times as long.

Depending on how long you keep your lights on every day, an energy-saving light bulb could save you around £2.50 per year – or around £6 for brighter bulbs or any you use for more than a few hours a day. So by replacing all the old-style bulbs in your home with energy-saving bulbs, you could cut around £37 a year off your energy bill and save 135kg of carbon dioxide. Over the lifetime of all the bulbs, this could save you £590 on your energy bills and bulb costs – and save the planet from three tonnes of CO2.

If every UK home installed three energy-saving light bulbs, it would save enough energy to power all the UK's street lights.

How else could I save electricity?

Although energy-saving light bulbs are the clear winners when it comes to saving energy, there are other electricity-saving devices for homes include energy-saving plugs and rechargeable batteries.

To stop your computer using excess energy, you can buy an Ecobutton that plugs into a USB port. It flashes to tell you to press it when you’re taking a break, and then puts your computer into its most efficient energy-saving mode. When you start using your computer again, a screen shows you how much money and carbon you’ve saved.

Rechargeable batteries are also a good investment – as long as you buy good-quality ones that will last and hold their charge. You can also buy smart chargers which make sure your batteries don’t get damaged by overcharging.

How can I reduce the cost of heating my home?

If you insulate your roof and walls, improve your heating system and generally be a bit more careful, you can save around £300 a year. Not to mention cutting your home’s carbon dioxide (CO2) emissions by around 1.5 tonnes.

Which parts of my home can I insulate?

You can insulate walls, roofs, windows, doors, hot water tanks and pipes – and of all the things you can do to save energy, this will have the greatest impact.

In fact, if your home isn’t insulated:

  • 33% of heat is lost through the walls
  • 26% through the roof
  • 18% through the windows
  • 12% is inevitably lost because of draughts and essential ventilation
  • 11% through the door and the floor

What’s the best way to insulate my home?

Starting from the top of the list above:

  1. Walls: cavity wall insulation is one of the best ways to keep heat in and save money – it can cut around £115 off your heating bill each year
  2. Roof: loft insulation is effective for at least 42 years and should pay for itself many times over
  3. Windows: double-glazing keeps the heat in, and also reduces noise and condensation – if you replaced all your old single glazing with Energy Saving Recommended double glazing, you could save around £135 each year
  4. Draughts, doors and floors: get draught excluders for doors and windows, and an eco flap for your letterbox – and fill in any gaps between skirting boards and floorboards.

You can also insulate – or ‘lag’ – your hot water tank with a cylinder jacket. You’ll find your water stays hot longer, and you’ll waste less energy heating it. And you could save around £35 a year.

Hot water pipes lose heat if they’re out in the open between the boiler and hot water tank – so if you can see them, insulate them. This could save you around £10 a year on your fuel bills.

You can even insulate yourself. Putting on extra layers of jumpers, vests and socks, wrapping up in a rug when you’re watching television, or adding an extra blanket on the bed will keep you snug without needing to ramp up your heating bills.

If you’re thinking of installing loft or wall insulation, you might even be able to get a grant towards all or part of it. Visit to find out.

Are there other ways to improve the energy efficiency of my heating and hot water?

Yes. Heating and hot water make up around 60% of the average fuel bill and, unless your home is newly built, your heating system’s unlikely to be as efficient as it could be.

If your boiler’s been around for 15 years or longer, you should definitely think about changing it for a younger, greener version. You could chop up to a quarter off your heating bills by replacing an old G-rated boiler with a new A-rated condensing boiler and a full set of heating controls.

Turning your heating thermostat down by 1°C can also cut up to 10% off your heating costs. For a gas-heated, three-bed semi-detached property, this could save you around £55 a year. In fact, there’s no need to set the thermostat on your hot water tank any higher than 60°C or 140°F.

You can also buy smart heating controls that let you access your heating and electricity controls remotely, so you can switch off the heating if you know you’ll be home later than expected.

How can I make my radiators work harder?

You could improve the performance of your radiators with energy-saving devices for homes such as radiator boosters, automatic bleeders and radiator foil.

Radiator boosters are white telescopic tubes that you place on top of your radiators. They draw the heat from behind the radiator and fan it around the room. This warms the room effectively, so you might be able to lower your thermostat setting. However, they do make a gentle humming noise, so might not be suitable for bedrooms.

Radiator foil does much the same job: it sits between your radiators and the wall and reflects the heat back into the room.

Automatic radiator bleeders release the build-up of air in your radiators, making them more efficient and saving you a messy and time-consuming DIY job.

How can I reduce the amount of water I use?

Once you’ve taken the obvious step of taking a (non-power) shower instead of a bath, there are gadgets to help with this too.

If you’ve got an oldish power shower, fit a water-efficient eco shower head. They can help you use less water by reducing water pressure, mixing air with the water or making the water ‘pulse’ rather than come out in a steady flow. However, they can be noisy and don’t always work well if you’ve got a low-pressure system. Most modern electric showers already include a low-flow shower head, so you don’t need to reduce the flow any further.

Your water company may be able to give you some of the most useful and best energy- saving devices free. For example, you could apply for a flow reducer to slow down the flow from your shower, or a ‘hippo’ for your cistern, so you use less water when you flush.

How can I tell whether I’m really saving any energy?

For the most accurate record of your energy use, try an energy monitor. It could show you how much energy you’re using, how much it costs, and the level of your greenhouse gas emissions.

The best energy monitors let you walk round your house switching items on and off, to see how much energy each electrical device or appliance uses. It can also show you how much you’re saving once you start using your energy more efficiently.

You can also get plug-in monitors, also known as energy-monitoring sockets, which plug in between the wall socket and the device you’re measuring. They show you much energy individual devices are using – and they’re a great way to check whether the electricity-saving devices for homes we’ve recommended are working.

What other energy-saving products for homes are available?

You’ll also find gadgets called voltage optimisers, eco kettles, disposable battery chargers, standby savers and solar phone chargers, but Which? doesn’t include any of them in its list of the best energy-saving devices. See products/guides/eco-products-which-recommends/eco-products-you-dont-need/ for more details.


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