Portable electric heaters don't keep the whole house warm like central heating systems do, but they do provide you with a heating boost exactly when and where you need it. They're a helpful companion during frosty days and freezing nights.
But are they eco friendly? And will you run up needlessly high bills? This comes down to whether you've bought a good model that suits your needs and how you use it. Read on to find out more.
The conversion of electricity into heat doesn't produce harmful by-products such as carbon emissions at the point of use. This is why you sometimes hear electricity being described as 'clean'.
But while the electricity you draw from a power outlet can be generated using renewable energy sources, electricity generation can still put a lot of CO2 into the atmosphere.
It depends where you live, but the electricity you use in your home is generated from a variety of sources, including renewables (around 41%, on average), gas (38%) and nuclear (21%). You can't guarantee that you're using renewable power when you switch on your heater because electricity from all sources is mixed-up in the grid.
Most electric heaters have a maximum rated output – usually 2,000 watts (2kW) or 3,000 watts (3kW). Good heaters also have settings where you can adjust heat output – the more choices, the more control you have to get the right temperature without wasting energy.
To work out your costs, multiply the hours you're using the heater with the energy output you're using in kilowatts to get the kilowatt hours used (kWh). This is what utilities companies use to calculate your costs.
Find out what your tariff charges you per kWh and multiply this and you'll arrive at the figure your heater will cost you to run.
For example, if you use a 2kW fan heater for an hour every morning and you pay 21p per kWh, then you'll be spending £2.94 every week on electricity for your heater.
It hasn't always been mandatory for electric heaters to have temperature sensors, but now it is. This is because of EcoDesign Lot 20, legislation that affected the design of electric heaters in order to create a minimum standard for energy efficiency. Because of this, every heater you buy can detect the temperature of the room and adjust its output to ensure a stable room temperature.
Although this legislation created minimum standards, we go beyond this in our test lab to differentiate heaters with good thermostatic control from the ones with low quality thermostatic control.
It's not easy to manufacture a heater that can detect the temperature easily because heaters' thermostats are so close to the heat source. Thermostats have to account for this when they sense the ambient temperature of the room. There's a lot of room for failure.
A poor thermostat can lead to a range of bad consequences which increase wastefulness.
Effective thermostatic control gives you heat when you need it, in the correct proportions. This reduces waste and maximises energy efficiency.
We test four types of heater: fans, convectors, oil radiators and oil-free radiators. They each have different strengths and weaknesses.
The truth is that no type is automatically more sustainable than another and they're all capable of converting electricity into heat efficiently.
But different heaters suit different users and you can avoid waste by using the heater that best suits your needs.
Be careful if you're thinking about buying a second-hand heater. This requires trust in the seller and checking on your rights, because faulty or broken heaters can be wasteful at best and dangerous at worst. We've seen heaters being recalled because they're a fire risk when their components fail.
Don't buy a heater that was designed before 2018 which doesn't have a built-in thermostat. A heater like this couldn't be sold new now because it's so inefficient.
Insulating your space is crucial because most heaters work by convection most of the time and you don't want your hot air floating off into the horizon. The better your home holds on to warmth, the less electricity your heater needs to draw from the mains to try and keep up.
Finally, think about your tariff. Although heaters are clean because they don't create emissions at the point of energy conversion, they still rely on energy from the National Grid. Whether your electric heater relies on fossil fuels or renewables is beyond the control of the heater manufacturer.
There's a market for spare parts for some electric heaters. Components such as bezels, heating elements, thermostats, castor wheels and more may be available. For example, when we checked in October 2021, spare parts for some DeLonghi heaters could be bought online.
Right to repair laws don't cover electric heaters at the moment, so spare parts and access to components aren't guaranteed by law.
According to Recycle Now, around one million tonnes of electrical and electronic waste are generated every year. Every item that has either a plug, a charger, batteries or carries a crossed-out wheelie bin logo can be recycled - this includes electric heaters.
You can take your old heater to your local recycling centre or see if your local council offers a household collection service for small electrical items. Double check the weight and dimensions of your electric heater to see if it qualifies. Some heaters are small desk-sized gadgets, while others are large units.
It's especially important to dispose of an oil radiator carefully because oil pollution is ecologically destructive and oil that leaks on to the ground will have a suffocating effect on plants and creatures.
Oil is treated as a hazardous waste and needs to be disposed of locally at your nearest recycling centre that accepts it. Your council should offer advice online about where you can drop it off.