Is it cheaper to use an electric blanket or put on my central heating?

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I want to know how much cheaper it is to use an electric blanket than it is to turn my central heating on, please.

I have an electric throw, which is like a blanket with a heating element. When I switch it on and wrap it around me it's so cosy I don't need to put the central heating on.

Out of interest, how much cheaper will my energy bills be if I just use my blanket and not switch on my heating? I will supply details of both my throw and boiler.

Sam Barker of This Is Money replies: As the mercury drops, so too do reader queries about heating.

Energy bills are high, and are only going to get higher in the short term.

The Ofgem energy price cap, which is now £1,717 a year for average energy use, will rise by 1.2 per cent to £1,738 on 1 January 2025.

Blanket rule?: Most electric blankets are designed to be lain on, but some wrap around the body

However, as I said in an answer to a similar question I had recently, it is very tricky to give a straight answer to heating questions like 'what is cheaper, X or Y'.

This is because every house and person is different, and factors such as boiler efficiency, thermostat level and insulation all play a part in complicating the answer.

That said, on paper it is much cheaper to use an electric throw to keep warm than put your central heating on.

Your 160 watt (0.16kw) electric throw costs 4p to run for one hour, assuming you are on the typical price-capped energy deal where electricity unit rates are capped at 24.5p per kilowatt-hour (kWh).

Your 25kw combi boiler, by comparison, should cost £1.56 to run your central heating for one hour, assuming you are paying 6.24p per/kWh for gas at price-capped rates and your boiler is 90 per cent efficient.

That £1.56 cost could end up being lower, as once the temperature in your house reaches that of your thermostat then your boiler will switch off, and that could take less than one hour.

But whichever way you slice it, the electric throw clearly costs a tiny fraction of the cost of turning your central heating on.

However, the easy comparisons end there.

You may feel very warm - and frugal - using your electric throw, and they are undeniably great gadgets, with dedicated fans.

But the throw is only heating you, so as soon as you take it off you'll feel the full force of the chill.

You cannot keep it on forever, so I suspect you may need to rely on a combination of the throw and your heating. 

Having a cold house is also bad - for the house.

Not heating your home can mean mould and damp builds up, which can come with a repair bill that dwarfs the cost of simply running the central heating.

There is also the initial outlay of the electric blanket. They typically range between £50-£70, depending on the make and retailer.