How Much Electricity Space Heaters Use?

It might seem like a space heater is a great temporary solution to making certain areas in your house nice and toasty. But unfortunately, this thing might drastically affect your electricity bills.

Most space heaters use 1.5 kilowatts of power – that’s a lot of electricity. To find out how much you would have to pay, multiply the number of watts by the number of hours and by the rates of the electric company – 8 hours of coziness will cost you over $1.5.

Do all space heaters use the same amount of electricity? Is it more cost-effective to have your AC on or an electric heater and is there anything that you can do to prevent your energy bill from running up?

Here is the whole truth about space heaters. 

Do Electric Heaters Use More Electricity Than Air Conditioners?

A reverse cycle air con is actually 3 times more efficient than a space heater.

This is because the devices use drastically different heating methods.

How does a reverse cycle air conditioner work?

A reverse cycle AC will take heat from the air and then make it travel through a coil evaporator that has a liquid refrigerant. When the warm air passes through this liquid, it warms it up and essentially forces the liquid to turn into gas.

The temperature of this gas is going to become even higher while it circulates in the system, until, finally, the hot air is transferred to your room.

How does an electric heater work?

A space heater has a special heating element inside (an electrical resistor). When a current passes through this part of the device, the electricity turns into heat.

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So, basically, for every 1.5 kilowatts of heat, a space heater is going to need 1.5 kilowatts of electricity.

A reverse cycle air conditioner needs approximately three times fewer kilowatts to generate the same amount of heat as a space heater.

Of course, the exact numbers are going to depend on the model, the tonnage, and plenty of other factors. But unfortunately, a space heater is not an energy-efficient device, in any case.

Also, do bear in mind, that in order to heat up your house (or a few rooms, for example), you are going to need more than one electric heater. That would certainly add quite a sum to your energy bills.

How Much Electricity Does a Space Heater Use Per Month?

To figure out the exact numbers, follow our simple step-by-step instructions.

In our example, let’s find out how much does it cost to run a 500-watt heater for 8 hours per day in the course of a month.

  • Find the wattage of the space heater. Usually, the number is printed on the actual device or you can always consult the manufacturer’s manual that came with the heater.
  • 1.500-watt space heaters are, perhaps, the most common type, but some heaters can be smaller and others – bigger. In our case, we have a 500-watt heater.
  • To find out how many kilowatts of power the heater uses, you should divide the watts by 1000. So, our small heater needs 0.5 kilowatts of electricity.
  • In your electricity bill, the amount that you have used is measured in kilowatt-hours. Let’s say that you would like to keep the room warm for about 8 hours per day – multiply the kilowatts by the hours and you’ll find out how much power the heater is going to need every day (4 kilowatts, in our example).
  • If it has been a cold month, then you might have been switching on your space heater every single day. As a result, the device ‘ate’ 4 x 30 = 120 kilowatts of electricity in a month.
  • The average electricity rate in the United States is 13.19 cents. Our heater is going to cost us nearly $16 a month.

So, how much power does a small space heater use?

A small, 0.5-kilowatt heater will use around 120 kilowatts of power if you decide to have it on for 8 hours every day for a month.

Bear in mind that such a tiny device will be able to heat up only a small area in a single room.

How Much Does It Cost to Run a 500 Watt Heater for 24 hours?

Now you know how to solve this task.

500 watts are 0.5 kilowatts

Multiply the kilowatts by the hours (0.5 x 24 = 12)

Multiply the number by your electricity rate (on average, 12 x 13.19 = $1.6)

It will cost you around $1.6 to run a small, 500-watt heater for a whole day.

Different Space Heaters ; Their Electricity Use

How Much Electricity Does a Fan Heater Use?

A fan heater is, basically, an electric hot air fan. The majority of models are portable devices that operate thanks to ‘forced convection’. 

Even though fan heaters are relatively convenient and are able to heat up a small space quite fast, they are not the best option for those who suffer from allergies (the devices distribute plenty of dust throughout the room) and the little guys are extremely power-intensive.

In general, fan heaters can use anywhere between 1 and 2 kilowatts of energy.

Do Ceramic Heaters Use a Lot of Electricity?

These heaters work by making an electric current pass through a ceramic plate that absorbs the heat and then releases it into the room.

Ceramic heaters are considered to be very safe and they heat up incredibly fast which means that no energy gets wasted.

However, the majority of devices use 1.5 kilowatts per hour, if you are using them to their full potential. Some models come with built-in fans, so that would contribute to the electricity usage as well.

Do Oil Filled Space Heaters Use a Lot of Electricity?

The closed coil system of such a space heater is filled with oil. The device also has a thermostat that reads the temperature of the oil (not the air – and that’s the main difference between this space heater and all the other options).

Once the oil reaches its target temperature, the device gets switched off. That’s exactly why these heaters are considered to be more energy-efficient – you wouldn’t need to keep the device on all the time, in order for it to radiate heat.

However, when the heater is on, it will be ‘eating’ just as much energy as any other space heater from our list. The maximum power rating is usually 1.5 kilowatts, but you can choose to go for the low energy setting (0.7 or 0.8 kilowatts).

HeaterTypical Power RatingTotal Heating PowerFeatures
Air conditioner2 kilowattsAround 6 kilowattsInverter air conditioners are more energy-efficient than regular models
Fan heater1.5 kilowatts1.5 kilowattsThe device heats up the space very fast
Ceramic heater1.5 kilowatts1.5 kilowattsOne of the safest heaters
Oil-filled heater1.5 kilowatts1.5 kilowattsThe most cost-effective space heater, it gets switched off as soon as the oil reaches the desired temperature

Can Space Heaters Help You Save Money?

Space heaters are considered to be 100% efficient, as all the power that they consume is generated into heat. But it’s definitely not the best way to save some cash.

Only in case you’ll have your HVAC system turned off, while using a space heater to make a small area in your house warm, you won’t be driving up your energy bills.

According to the Department of Energy, space heaters might be less expensive to use than a traditional heating and cooling system, only if you are planning on using them in one room.

Here are a few simple rules that you should follow when trying to choose the most cost-effective space heater:

  • Go for a model with a thermostat. It is going to help avoid overheating and unnecessary electricity consumption.
  • Buy the newest models on the market. They are, in general, much safer than the older devices, and the last thing you want is to pay for different kinds of damage that the heater can cause to your house.
  • Find a heater of the perfect size for the room where you are planning to put it. Buying the biggest option available is totally unnecessary, while a heater that is too small won’t be able to properly heat up the space. 

To Sum Up

Do space heaters use a lot of electricity?

Unfortunately, these small, portable devices really do consume quite a lot of energy. In fact, the majority of models have a power rating of 1.5 kilowatts.

Keeping your space heater on all day long will definitely make your energy bills skyrocket. If your house has an installed HVAC system, using it to heat the space up will be about 3 times more efficient.

However, a space heater might come in handy on an extra cold evening, when you would need to quickly heat up a single room. So, having one in your house just in case might be a good decision.