How much electricity do fans use and how expensive is it to leave them on overnight

WITH temperatures soaring across the country this long weekend, many of us are turning to electric fans to help us sleep during the heat.

Brits are actually basking in the hottest August Bank Holiday Monday EVER today as thousands flock to beaches and swimming pools to keep cool.

 Brits are turning to electric fans to help them sleep during the heat


Brits are turning to electric fans to help them sleep during the heatCredit: Getty – Contributor

Others will use fans to cool down, but leaving it on for a long time will increase your energy bills.

Below we round-up everything you need to know.

How much energy does a fan use?

To find out how much electricity it uses, you’ll need to check the “wattage” of your fan as this tells you the amount of power that a fan needs to operate.

To then find the output you need to turn the wattage into kilowatt hours.

You do this by dividing it by 1000, which will give you how much output is used in one hour.

So if your fan is 70 watts output on its high setting and you always use this, divide 70 by 1000 = 0.07.

You then times this number by the amount of hours you’re using the fan.

For example, if you’re using it for 12 hours per night – 0.07kW x 12 hours = 0.84kW output.

How expensive is it to leave them on overnight?

Once you have your kilowatt output, you need to times it by the amount you pay for 1 kW of electricity – check your bill to find out.

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For example, if a kW costs 15p on your bill the sum will be: 0.84kW x 15  = 12.6p.

The equation is: Cost = power (kilowatt) × time (hour) × cost of 1 kWh (pence).

The Sun also asked energy experts from Energyhelpline to estimate the cost of running a fan for 12 hours a night, and they found that it’d cost you from 7.76p to 15.59p on average.

These figures are calculated based on the cheapest tariff available on the market in mid-July (13.87p per kW) as well as the UK’s standard variable tariff (18.56p per kW), using the output of a typical fan at 70Kw.

This means that by keeping your fan on for 12 hours every night during a month of 30.5 days, you’d see your energy bills rise by £3.55-£4.75.

What’s the difference between kWh and kW?

IF you’re trying to calculate energy usage the terms can be confusing, according to OVO Energy.

kW stands for kilowatt. A kilowatt is simply 1,000 watts, which is a measure of power.

A kilowatt hour (kWh) is a measure of energy.

So a 1,000 watt drill needs 1,000 watts (1 kW) of power to make it work, and uses 1 kWh of energy in an hour.

That’s why, if you leave a TV or computer on standby, it is still using power and creating a kWh cost on your energy bill.

Of course, costs will vary depending on the type of fan you have, how long you’re using it for and how much your energy costs.

Some tariffs also let you pay less at night, meaning the cost will be lower.

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If you don’t want to calculate the cost yourself, you can use this energy usage calculator by Sust-it.

It’s far cheaper to use a fan rather than an air conditioner, but on some occasions fans aren’t enough.

Just carefully calculate the cost in advance if you’re thinking of splashing out.

Do fans make a room cooler?

Although fans can’t make a room cooler they can make you feel cooler.

The air moving over your skin can lower your body temperature but won’t do much about the heat inside a room.

So if you don’t plan on being in the room there’s no point of leaving the fan on.

Fans just move air around the room, and could in fact make you hotter.

If your fan is failing to keep you cool, then try adding a bowl of iced water in front of it.

Just be aware that those with allergies and asthma have been warned that fans could be making their symptoms worse.

People have shared their tips on surviving a heatwave without air conditioning that won’t cost a penny – including the frozen jug trick.

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Plus, here’s how to keep your pets cool in the heatwave as well a warning signs to look out for.

Public Health England advises Brits not to use fans as they could lead to high temperatures and dehydration

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