Are Electric Space Heaters Energy Efficient?

Learn What Makes a Space Heater Energy Efficient


Space heaters are very popular, and the most common types of electric space heaters range from electric convector heaters, fan heaters, and oil filled radiators.

For those that don’t know, space heaters heat the space around you, the air in the rooms. Whereas infrared or halogen heaters, heat you and objects directly, but have very little effect on heating the space/air in the room.

Now on to The Question, Are Space Heaters Energy Efficient?

The answer is, it depends, you see, it is not a simple yes or no answer. Energy efficient space heaters have numerous features, and there is one main feature that makes them energy efficient. Let’s have a look at them.

Make Space Heaters Energy Efficient With a Thermostat Function

A thermostat is the main feature that will make space heaters’ energy efferent. A space heater that can be set to a certain temperature, and cut on and off when the temperature is above or below, will use less energy, and be more energy efficient, compared to a space heater that can only be switched on and off.

For example, let’s say you have two 1000 watt electric oil filled radiators, one has a thermostat set to 22 degrees and the other doesn’t. You have them both on for 1 hour, the electric oil filled heater that does not have a thermoset will cost roughly 0.28p for the hour, if you are charged 0.28p per kilowatt-hour.

The oil filled heater that has a thermostat set to 22 degrees may only need to be on for a total of 30 minutes in an hour to provide nice comfortable warm heat, and this will cost you around 14p, making it more energy efficient.

In the first scenario, the heater may make the room a lot warmer than you need it to be, and you end up getting used to it the extra heat, hence you have it on full blast for 1 hour, and this ends up costing you more money than it needs to.

In the second scenario, you know 22 degrees is an enjoyable comfortable heat for the room, you set the thermostat, the heater regulates the heat output according to the set thermostat temperature, you don’t need to think about it, you have a nice warm room, and it cost you less to heat thanks to the thermostat. This can save you a lot of money on your monthly bill.

As you can see, space heaters are only energy efficient if they have a thermostat, all space heaters require a certain number of watts to heat rooms. A 2000 watt heater will heat a room around 20 square meters, it will struggle to heat a room around 30 square metres, for 30 square meters you will need a 3000 watt heater.

A space heater that can regulate its temperature output according to your desired room temperature will be the most energy efficient. As it will not need to constantly use full power, and will draw on power when the temperature drops below your desired set temperature.

Different Types of Space Heaters for Energy Efficiency

Different types of electric space heaters are efficient in different environments. For example, a fan heater will be more energy efficient in a poorly insulated room, when compared with a convector or oil filled radiator.

Why is a fan heater more energy efficient in this scenario? Because it can throw out hot air fast due to its built-in fan, it forces hot air into a space/air. A fan heater can warm a room quicker than the heat is being lost.

With a convector or oil filled radiator, it relies on a process of warming the cold air at the bottom of the room, and this can take a while to get going in a poorly insulated space. This means you are losing the hot air in the space quicker than it can retain it and warm the space/air. You may need to run these heaters twice a long in a poorly insulated space to get the same effect as a fan heater, meaning you will use more energy to get the same result.

In fairly good insulated spaces, convectors and oil filled radiators are good, but when it comes to poorly insulated spaces, a fan heater will be more energy efficient to heat the space. As you can see, different types of electric heaters work differently to heat space.

What is An Electric Convector Heater?

An electric convector heater is a type of heating device that uses convection to warm the air in a room.

The heater works by drawing in cold air from the bottom, heating it internally using an electric heating element, and then expelling the warmed air from the top. As the warm air rises, it circulates throughout the room, displacing the cooler air which then moves towards the heater to be warmed. This continuous cycle of warming and circulating air helps to maintain a consistent temperature in the room.

Convector heaters are typically compact and lightweight, making them portable and suitable for use in various rooms. Many models come with built-in thermostats for temperature control and may feature different heat settings. Some advanced models also include timers or remote controls for easy operation.

What is a Fan Heater?

A fan heater is a type of heating device that uses a fan to distribute warm air throughout a room. It works by passing air over a heating element, such as an electric coil or a ceramic plate, and then propelling the heated air into the room using a fan.

Fan heaters are known for their ability to quickly raise the temperature in a room, making them an ideal choice when instant heat is required. They are usually compact and portable, making them convenient for use in different settings such as offices, bedrooms, or garages.

Many fan heaters come with multiple heat settings, allowing you to control the level of warmth produced. Some models also feature a cool air setting, effectively turning the heater into a cooling fan during warmer months. For safety, many fan heaters are equipped with features such as tip-over switches, which automatically turn off the heater if it is knocked over, and overheat protection, which shuts off the heater if it gets too hot.

However, fan heaters do have some drawbacks. They can be a bit noisy due to the fan operation, and they may not be the most energy-efficient option for long-term heating, as they tend to lose heat quickly when turned off.

What is an Electric Oil Filled Radiator?

An electric oil filled radiator is a type of heater that uses electricity to heat oil within the radiator. Despite the name, the oil in the radiator is not burned to produce heat. Instead, it serves as a heat reservoir that absorbs and retains heat generated by the electric element.

The way it works is simple: when the heater is switched on, electricity heats the thermal element inside the radiator. The heat then gets transferred to the oil, causing it to warm up. The heated oil circulates around the radiator, releasing its warmth into the room through the process of radiation and convection.

One of the main advantages of oil-filled radiators is their efficiency. Once the oil is heated, it stays warm for a considerable time even after the heater is turned off, providing a steady and consistent source of heat. This makes oil-filled radiators ideal for maintaining a constant temperature over longer periods, such as overnight.

However, oil-filled radiators take longer to heat up compared to other types of heaters, such as fan heaters or convector heaters. They are also typically larger and heavier.

Most oil-filled radiators come with a thermostat for temperature control and multiple heat settings. Some models may also feature timers or eco modes to help save energy.

Can You Heat a Room for Pennies an Hour?

No, you cannot heat a room for pennies an hour, an average size room with double glazed windows will most likely require a 1000 watt electric heater minium. If you run a 1000 watt heater for one hour, this will cost you around 0.28p per hour with the current price cap, or whatever your electricity provider charges for 1 kilowatt-hour.