Hot or stuffy rooms call for a continuous cooling breeze. But how much does it cost to run a fan? And will leaving one on overnight, or all day in a home office, result in big energy bills?
Fans can be indispensable in warm weather – many of us leave one on low all night to ensure a good night’s sleep, pop one on a desk to combat hot and humid days, or keep it on hand for home workouts.
So how much electricity does your fan use? We’ve worked out how much you can expect to spend per hour to run a fan – as well as how you can prevent your bills from spiralling and save energy at home.
How much does it cost to run a fan?
The good news is that fans are surprisingly energy-efficient, especially when compared to an electric air-conditioning unit.
If you want to work out exactly how much your fan of choice costs to run you’ll first need to work out how much electricity it is using. You can do this by checking the wattage. This should be shown on the fan or the instructions leaflet. Once you know the wattage of your fan, convert this into kilowatt-hours. It might sound complicated, but all you need to do is divide the wattage by 1,000 to give the amount of energy it uses per hour.
Mini models can use as little as 5 watts, while large bladed fans can be more than 100 watts. For example, if you have a 50-watt fan, you would divide 50 by 1,000 to get 0.05. If you are using it for ten hours a day, you’ll then multiply 0.05 by 10 giving you 0.5kW. This is how much energy the fan uses in a day.
To work out the cost, you will need to know how much you pay for one unit of energy (1kw). This should be listed on your energy bill. According to the Energy Saving Trust the national average price (as of November 2021) per pence/kWh of electricity is 20.33p. We have rounded it to 20p for illustration purposes.
Multiply the cost of a unit of energy by the kW output of your fan and that will be how much it is costing to run your fan.
- An example 18-inch bladed floor fan uses up to 110 watts at full speed, which is 0.1 kWh. So if you’re paying 20p for energy,, it’d cost 2p an hour to run. Over 10 hours, it would cost 20p.
- Compared to an example bladeless fan, which uses 56 watts or 0.056 kWh, its cost per hour is just over 1p. Over 10 hours, it’d cost 11.2p.
- An example tower fan that uses 35 watts or 0.035 kWh is even cheaper to run at less than 1p an hour and over 10 hours, just 7p.
Are some fans cheaper to run than others?
While an electric fan might be offering you some relief, for example, helping you if you’re too hot to sleep, the last thing you want is to be hit with a nasty surprise when your electricity bill comes through. So it’s worth knowing that different types of fans will be more affordable to run over long periods than others.
- Bladed fans tend to use the most energy. Typically, the larger the blades, the more energy it needs to turn them.
- Tower fans often have lower power consumption compared to bladed fans but tend to be less effective at moving air, so you may need to have them on a higher setting.
- Bladeless fans, sometimes called air multipliers, draw air in before passing it over small asymmetric blades that increase the pressure and airflow, before pushing it out into the room. This means running them can be more energy efficient than fans with more moving parts.
What energy saving features should I look for when buying a fan?
If you’re shopping for the best fans to save energy, look out for these useful features that make a model as energy efficient as possible.
1. DC motor
Fans that have a DC motor rather than AC will be more energy efficient. For example, the Bionaire ISF004 Desk Fan has a DC motor that uses 63% less energy than a traditional fan. Copper motors can also help reduce energy loss by generating less heat.
Setting the amount of time your fan will run instead of having it on constantly can save energy. Some models, such as the Dyson Cool AM07, have a sleep timer that can be programmed to turn off after preset intervals so it doesn’t have to run through the night.
3. Variable speeds
A choice of more than one speed will help to reduce your fan’s energy usage. Once the temperature is comfortable, turn it down to a lower setting. Look for models with remote controls to make this even easier, so you won’t have to get out of bed, or be distracted from what you’re doing.
How can I cut the cost of running a fan?
1. Turn it off as you go
Fans don’t make a room cooler by themselves, they can only make you feel cooler by moving the air over your skin. If you’re leaving the room, switch the fan off. Once the temperature outside drops, opening a window allows cool air to be drawn into the room, so it could be worth running a fan an hour or so before you get into bed.
2. Close the curtains
‘Letting in the sunlight on a bright day might seem the natural thing to do but this can create a greenhouse effect with up to 30% of unwanted heat gain from windows,’ says Evan Stevens, Head of Environmental Care at Dyson. ‘Keep the windows, curtains or shutters closed during the day to minimise the amount of sunlight entering the home.’
3. Stay frosty
Rather than turn your fan up, use it to cool down the air in the room. Pop a bowl of ice and cold water in front of it. This causes small droplets of cold water to circulate, cooling your skin down faster.
4. Keep it clean
As fans circulate air, they’re prone to picking up dust and other particles. Make sure they’re working as efficiently as possible by wiping down blades, cages and vents while they’re unplugged.