The country is being hit by a heatwave, but the cost of using a fan to keep cool tonight can seriously add up

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A heat alert has been issued for central, southern and eastern England, the Met Office said, amid a heatwave that will leave some parts of the country hotter than Jamaica, the Maldives and the Bahamas.

While the North East is not expected to reach such blisteringly high temperatures, temperatures in the high 20s Celsius are expected over the weekend.

Many are looking at ways to keep cool and reach for a fan to do the trick, and energy switching service Migrate estimates almost half the population use electric fans to help them stay cool during the hot, summer nights. But you might be in for a nasty shock when you get your electricity bill.

Read more: Met Office updates Amber warning for extreme heat for parts of North East

The typical 120w pedestal fan using costs around 3.4p an hour to run on average, according to Uswitch. That doesn't sound too bad if you just use if for an hour or two at a time. But leave it on all night and the costs soon start to rack up.

Switching your fan on at 10pm when you turn in for the night and leaving it on until 8am will cost you around 34p in energy costs. Multiply that by seven days if you do it every night and the cost is around £2.38, which is a massive 75p more than last summer, thanks to rising energy bills. One tip to get the maximum benefit from your fan is to put a bowl of ice in front of it and create your own DIY air conditioner.

But if you're watching the pennies, be grateful that most UK homes don't have air conditioning - for even a portable unit costs around 28p an hour to run - of nearly £20 if you run it for the same time every night for a week.

Of course, if you don't want to use a fan there are other ways to stay cool. The obvious ones are opening a bedroom window, sleeping without bedcovers and switching to a lower tog rated duvet. You can block out the sun by keeping your bedroom blinds or curtains closed during the day if you remember, then open them when it starts to get cooler.

If you have the option, sleeping in separate beds can be cooler than sharing, and taking a cool shower before bed can mean you start the night off cool at least. More imaginative ways to keep cool include freezing or filling a hot water bottle with ice water, using a spray bottle filled with cold water for a cooling mist if you wake up in the night and chilling a pair of socks in the fridge and putting them on before bed

Becky Mitchell, a forecaster for the Met Office told The Mirror : "It is quite unprecedented. The most likely outcome is we'll see temperatures in the mid 30s. There's a 30% probability we will get heat in the high 30s, which would break the UK's hottest temperature on record. Temperatures are likely to peak towards end of next week. There's lots different model outputs one or two are showing extreme temperatures like 43C. However, we are very unlikely to see 43C."