What are the best energy-efficient heaters for your home?

02 December 2020 | Aimee Tweedale

Boiler broken down? Need some extra warmth in your conservatory or garage? Or just trying to save a bit of money on your central heating bills?

If so, you might be looking for a standalone heater. In that case, you’ve got a lot of decisions ahead! Do you want a fixed heater that will heat one room, or a portable heater you can dig out on cold days? Do you want a gas or electric heater? And that’s before we even get into the difference between an oil-filled radiator and a convector heater!

A dog lying down next to a radiator

Don’t worry: we’re here to help. In this guide we’ll talk through the different types of types of space heater you can get, and the pros and cons of each.

Whether you’re looking to cut down on your running costs, or improve your home’s energy efficiency, the right heater is out there for you.

Do I need a standalone heater?

There’s more than one way to heat a room. Whichever one you choose, a standalone heater can help you cut down your running costs and make your home more efficient – but only if you’re being smart. 

Powering individual heaters alongside your central heating system is a surefire way to end up paying big bills. It can also massively increase your carbon footprint.

But if you’re in one of the following situations, an energy-efficient heater could well be a bright idea:

  • You want to heat a space that doesn’t have central heating (like your garage, or an outhouse)
  • You want to heat one room at a time, with the central heating system turned off
  • You need fast, extra warmth for someone who’s elderly or has limited mobility
  • You need a back-up heater for when your main heating system isn’t working

What type of standalone heater is right for me?

When it comes to choosing a standalone heater, you’re spoilt for choice. 

First, there’s gas vs electric. Gas tends to be cheaper to run, but electric heaters are much more efficient, and more environmentally-friendly.

Then there’s the choice of fixed vs portable: do you want the heater to stay in one room, or move around?

Your heat source options can be a bit baffling. So here’s a breakdown of the main types of heat source for your home.

Guide to energy-efficient heaters for your home

Portable gas heaters

As the name suggests, portable heaters can be picked up and carried around, so you can use them anywhere in your house. These are the main types of gas-fired portable heater:

  • Radiant gas heater: ideal for spot heating a specific area.
  • Portable gas stove: like a mini traditional fireplace, these heaters are cosy and pleasing to the eye, but more difficult to move around.

How efficient are they? 

Overall, gas heaters are less efficient than electric. This is because they tend to leak heat and fumes. They’re also powered by a non-renewable fossil fuel, which automatically makes them less green than an electric heater (which you could run with renewable electricity).


Portable gas heaters are cheaper to run than electric heaters – because gas generally costs less than mains electricity.


There are a few drawbacks, in spite of the lower running costs. Firstly, gas heaters tend to be quite heavy and unwieldy to move around. They can also be unstable, so need to be watched if you have small children or pets around. And you’ll need to keep the windows open or ventilate the room, to let out the water vapour they create. Oh, and don’t forget about keeping stocked up on gas cylinders, too!

Fixed gas heaters

A fixed heater is usually mounted to your wall, which means it’s not going anywhere. Broadly, there are two main types of fixed heater powered by gas:

  • Gas fire: these can look really appealing, and create a focal point for a room, just like a real fire (without any need for a chimney). You could get one with or without a flue – but definitely go for a flue if you want the most bang for your buck, as they waste less heat.
  • Gas convector heater: these aren’t as attractive – they look more like a typical radiator – but they’re cheaper to run.

How efficient are they?

If you’re worried about leaking heat and fumes, you need to make sure you get a gas heater with a balanced flue. These are the most cost-effective, as they’ll keep the heat in – but they’re still not as efficient as electric heaters.


Fixed gas heaters are more efficient than portable gas heaters, and they cost less to run than electric heaters.


Again, they’re not as efficient as electric heaters – and definitely not as cost-effective as your central heating system  – so they should be used less. There are also some safety risks with gas heaters that you don’t get with electricity. You’ll need to get it installed by a Gas Safe-registered engineer.

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Portable electric heaters

This is the option most people go for. 

Electric space heaters are easy – you simply plug them in, and they heat up quickly. They also cool down fast when you need to put them away again. Plus, they’re cheap, which is what attracts most people! (But that doesn’t mean the running costs are low.)

Here’s a breakdown of the different types of portable electric heater, and the advantages and disadvantages of each. 

  • Fan heaters: the lightest, most portable option of all the portable heaters, these fast-heating devices are great for targeting a specific area. The downside? You’ll have to put up with the fan noise!
  • Convector or convection heaters: these work by warming the air immediately next to them, then creating a cycle of hot and cold air, until the whole room is heated evenly. They take a little longer to get the job done, but the result is worth it.
  • Halogen heaters: another quick-heating option, halogen heaters are favoured by the thrifty, being among the cheapest to run.
  • Oil-filled radiators: oil is great at holding on to heat, which makes oil-filled radiators among the most efficient. They’re also one of the cheapest.

How efficient are they? 

Very! All electric heaters have a 100% efficiency-rating, because they turn all the energy they use into heat.

Portable electric heaters are even more efficient if they have thermostat controls, so you can set them to switch off once the room is the temperature you want. If your heater doesn’t have a thermostat, you could create the same effect with a separate plug-in thermostat, or even a simple plug-in timer.


As well as being the most efficient option, electric heaters are very easy to install and use. They’re cheaper and safer than gas heaters, too.


Though they’re usually cheaper to buy, electric heaters are more expensive to run than gas heaters (the higher their wattage, the more they cost). And being portable, you’ll also need to be careful if you’ve got small children or pets around.

Fixed electric heaters

Looking for an energy-efficient, wall-mounted electric heater? Most of the portable electric heaters listed above (fan, convector, etc) can also be fixed to your wall. 

There’s also another option:

  • Storage heaters: these smart heaters charge up during off-peak hours, when demand for electricity is low, and then use that energy to heat your room when you need it. They’re great for the planet, and for your wallet.

How efficient are they?

Electric heating is generally always more efficient than gas. There’s no wasted energy, and – if you’re using renewable electricity – no fossil fuels. 


Fixed electric heaters are far easier to install than gas – you just need wall fixings and a power source. They also usually have a lot more features to help you control your heating. Some are even Wifi-enabled!


As with any standalone heater, these are still less efficient and cost-effective than your central heating system. Our advice is to use them sparingly (with thermostat controls if possible).

For more, read our ultimate guide to storage heaters.

Guide to energy-efficient heaters for your home

What’s cheaper: gas or electric heaters?

Even though gas heating is generally less efficient, it’s around 3 times cheaper than electricity – so if you’re worried about costs, it might be right for you!

Electric heaters are cheaper to buy upfront. The cheapest portable electric heaters are oil-filled radiators (around 21p an hour) or halogen heaters (17p an hour).

The cheapest fixed electric heater to run is a storage heater – which will only set you back around 13p an hour1. Be prepared to shell out a bit more for the installation, though!

So, what is the most energy-efficient heater?

Let’s take it back to basics: what is energy-efficiency? If something is energy-efficient, it lasts longer and works better, without wasting any energy. This is not only good for your bank balance, but also for the planet. Having an energy-efficient home means you’ll be warmer, richer, and have a lighter carbon footprint

When it comes to heaters, gas heaters leak heat and fumes, but any type of electric heater is 100% efficient. If you don’t want any heat being wasted, go electric. 

Of course, gas heaters also run on natural gas, which is a fossil fuel. This means that electric heaters are the greener choice. And if you’re using renewable electricity to power your heater, it will always be cleaner and better for the planet than a gas-guzzler. 

But remember: space heaters are only efficient if you use them to top up your central heating system when needed. Don’t use them as your main heat source! That would take far more energy than your usual central heating. 

For more tips on how to maximise the energy efficiency of your heating, read our guide to 120 ways to save energy at home. Plus learn how to stay warm over winter without using so much heating.

How can I make my central heating system more efficient?

Want to go one step further, and replace your central heating system? It can be expensive – but the savings are worth it when you remember that heating accounts for 64% of the average household’s energy bills2!

If you’re looking for heat sources that could save you money and help save the planet, consider one of these more long-term options:

For even more inspiration, check out our blogs on low carbon heating options for your home, and working out how much energy you use for heating.

Being more energy-efficient with your home heating can help you save on your bills – but why stop there? Discover even more ways to be energy-efficient at home.

The UK Government’s Renewable Heat Incentive (RHI) scheme currently offers quarterly cash payments, just for installing a carbon-kicking green heating system at home. Find out more on our blog.

Get zero-carbon heating with OVO

Did you know that heating our homes accounts for a whopping 15% of the UK’s carbon emissions4? If you live in the South East and you want to be part of the fightback against climate change, sign up to OVO’s Zero Carbon Heating Trial, to fit your home with energy-efficient smart tech. Find out more about the offer here.

Keep the heat in this winter: 8 quick tips for a more energy-efficient home

Remember, standalone heaters are just one way of making your home more energy-efficient. If you can keep warm without using any extra energy at all – by wrapping up warm, for example – even better. 

Here are 8 quick and affordable ideas for keeping your home cosy this winter:

  • Move furniture away from radiators. You'll notice how much warmer the room is almost immediately.
  • Draught-proof your windows and doors, using some handy DIY rubber seals, or an old-fashioned draught excluder. This makes sure the warmth stays inside, where it should be!
  • Keep furniture and clothes away from radiators, so they don’t stop heat from circulating.
  • Keep your heaters and radiators clean. And make sure you bleed your radiators at least once every year, so they’re not guzzling more energy than they need to stay hot.
  • Use timers and thermostats wherever you can.
  • Wrap up warm in your favourite jumpers and blankets.
  • Getting a smart meter will help you watch the energy you’re using, so you can see exactly where you’re wasting it, and make changes to save money.
  • Also think about getting a smart thermostat installed, which will give you complete control over your heating!

Learn even more ways to save energy and money. Check out our guide to reducing your gas and electric bills.

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Sources and references

3  Estimated figures based on installing a new A-rated condensing boiler with a programmer, room thermostat and thermostatic radiator controls (TRVs) in a gas heated home from an older boiler with a programmer and room thermostat. Savings will vary depending on the size and thermal performance of your home. Source - Energy Saving Trust: March 2019.

4  This figure comes from this report by the Committee on Climate Change and its Adaptation Committee.

5  The renewable electricity we sell is backed by renewable certificates (Renewable Energy Guarantee of Origin certificates (REGOs)). See here for details on REGO certificates and how these work.

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