Homeowners Professionals
Renewables

A guide to electric radiators

The most popular way to heat a home in the UK is with a gas boiler. In fact, gas boilers account for over 90 per cent of the heating market. This method involves the pumping of hot water around a system to warm up the radiators that are located around your home. These in turn transfer the heat into the rooms of your home.

However, not every home can be connected to a gas supply and there are alternative ways to heat your home. You may consider using a heat pump, an appliance powered with electricity instead of gas, or you might look into electric radiators. The latter are commonly found in bathrooms, such as electric towel rails, however if you want to find out more about how you can use them in the rest of your home, read on.

How do electric radiators work?

Electric radiators and heating work in a similar way to the typical ones you find in a gas heating system.

The most common types are:

  • Oil filled electric radiators
  • Electric convector heaters
  • Infrared heating bar (visibly glowing)
  • Infrared panel heaters

When switched on the surface of the radiator will get hot enough to warm up the room it’s located in. This means that it works using convection as a standard radiator does (the heat moves to cooler air, carrying it into the room you want to heat). Once the electricity supply is turned off, the fluid inside the radiator will begin to cool. For infrared based electric radiators both the heating and cooling down will be more instantaneous as there is no fluid to heat or retain. This means you have much more control over when and how long you want the radiator on for and some can even be controlled with a smartphone or smart thermostat. 

Are electric radiators good?

There are a number of benefits to having electric radiators.

The first is that they’re low maintenance. Traditional water-filled radiators may occasionally need bleeding to remove air that can build up inside them and they can become clogged with dirt and debris. This must be kept on top of, otherwise their efficiency can decrease rapidly. However, electric radiators contain no internal moving parts, so there’s less chance of a fault occurring, and they don’t need to be bled. The fluid that is stored within (oil filled) them doesn’t move and won’t need refilling or pressurising. Instead, the radiator can simply be turned on. This could result in lower maintenance costs over the longer term.

These devices heat up much faster than water-filled radiators too. If you’re feeling a little chilly in a home with a gas heating system, you’d need to turn the heating on and wait a while for the boiler to warm up the water and deliver it around the system. This may also be a waste of energy, as the boiler is heating the whole house and not just one room, unless the home has been zoned. With an electric radiator, you can flick it on and it will heat up very quickly.

In a smart system that contains multiple electric radiators, you could set a different temperature for each room in the house, meaning you can keep your bedroom at a cool 18 degrees while your living space is a slightly warmer 20 degrees, for example. You could also programme these to come on as and when you wanted them, just like in a gas boiler system.

So this all sounds very promising - what’s the drawback? The issue is the current cost of electricity per kWh compared to gas, approximately 15.00 pence per kWh* for electricity and 4.00 pence per kWh for gas ), however this can be offset by the cost of buying the product in the first instance.

*Prices per kWh indicative at 06/2021

Are electric radiators cheap to run?

It’s stated that electric radiators are 100 per cent efficient. This is because they use 100 per cent of the electricity provided to heat a room and so they are an energy-efficient way to heat your home. However, electricity is more expensive per kilowatt hour (kWh) than gas, and so the costs of running an electric radiator can add up very quickly. As stated above gas currently costs around four pence per kWh in the UK, whereas electricity costs around 15p per kWh. Obviously exact figures will depend on the time of year, the fluctuation of international fuel markets and your energy supplier, however in the short term we are still likely to see big difference in the costs between these two fuels.

It is for this reason that electric radiators are not cheap to run. In fact, it may be cheaper to turn a gas boiler on and heat your whole home than it is to heat a few rooms with electric radiators.

But how much it costs to run an electric radiator depends purely on how much electricity it uses. The more energy it requires, the more it will cost.

How much electricity does an electric radiator use?

Electricity usage is measured in kWh. You can work out the kWh of an appliance by knowing its wattage (W) and multiplying this figure by how long you want to use it for. For example, a 100 W bulb that’s on for 10 hours would use 1 kWh of electricity (0.1 kW x 10 hours = 1 kWh).

In using this calculation and multiplying the number of kWh by the cost of electricity, you can work out how much it costs to run almost any appliance.

Electric radiators are generally sized in watts. They can go from very small (around 300 W) to very large (around 2,500 W). The most popular sizes are:

  • 330 W
  • 500 W,
  • 750 W
  • 1,000 W
  • 1,210 W
  • 1,500 W
  • 2,000 W.

Remember that you should always size a radiator correctly, otherwise it may use too much energy or fail to heat the room sufficiently.

To work out how much electricity an electric radiator uses, take the size of your radiator and consider the number of hours it will be on for. In our example, we’ll say that you want a 1,000 W radiator on for three hours in the morning and three hours in the evening, a total of six hours per day.

First, you must change the wattage into kilowatts. We’ll do this by dividing the watts by 1,000. In this example, 1,000 W is equivalent to one kW.

Then we’ll multiply one kW by six hours, which gives us six kWh. This is how much electricity your 1,000 W radiator will use per day. At a cost of around 15p per kWh of electricity, an electric radiator could cost around 90 pence per day.

Let’s compare this to the running costs of a gas boiler. A 24 kW boiler that’s on for six hours a day would use around 144 kWh of gas in a day. At a cost of four pence per kWh, that’s a daily running cost of £5.76. This may seem like a substantial amount more than the £0.90 to run an electric radiator, but don’t forget that a gas boiler is heating your entire home, whereas our calculation shows the cost of just one radiator. The average home has around 10 radiators, and so it would cost £9 to heat your home with electric radiators every day, almost double that of a gas boiler.

If your home cannot be connected to a gas supply, there are alternative ways to keep your home warm while also keeping costs down. You may consider having solar panels installed. These would be able to partially power your electric radiators or a heat pump and are certainly a more eco-friendly option when combined with a renewable energy source.