Heating the person instead of the room

On cold evenings some people switch on an electric heater and others wrap up in an electric blanket or heated throw. The two work differently: the heater warms the air of the whole room, the blanket warms only the person using it. That is why the blanket usually uses a small fraction of the energy. This calculator compares the cost of the two for the same hours, shows what an hour of each costs and how many seasons the blanket takes to pay for itself.

It works in any currency: enter the power shown on your appliances' rating plates.

How the calculation works

• Energy: average power in watts × hours a day × days, divided by 1000 to get kWh.
• Cost: kWh × energy price, for the blanket and the heater.
• Saving: the difference between the two season costs.
• Payback: blanket price divided by one season's saving.

The verdict is based on the ratio between the two powers, that is the blanket's cost as a percentage of the heater's, which does not depend on the currency.

What power to enter

Single blankets usually draw a few tens of watts, double blankets and larger throws around 100-150 W. Many models have several settings: they heat on high for a few minutes and then stay on low, so average power is below the rated value. Electric heaters usually draw 500 to 2000 W, and a thermostat makes them cycle once the room is warm. Enter the average power you expect, not just the maximum.

Blanket and heaters compared

With 4 hours a day for 120 days and energy at 0.30 per kWh:

The cost ratio stays the same whatever the number of hours: with a 60 W blanket and a 1500 W heater, the blanket always costs 4% of the heater, whether you use it one hour or eight hours a day.

How much the hours of use matter

With a 60 W blanket and a 1500 W heater for 120 days:

The bands of the verdict

• Below 5%: the blanket costs a tiny fraction of the heater.
• 5% to 15%: the blanket costs much less.
• 15% to 35%: the blanket costs less.
• Above 35%: the blanket costs less, but the advantage narrows.
• Blanket equal to or above the heater: an unusual case worth rechecking.

Not the same service

The blanket warms only the person using it, and only while on the sofa or in bed; the heater warms the room for everyone and lets you move around. Often the best option is to combine the two: keep the heating a little lower and use the blanket when resting. In a home with central heating, the real saving depends on how much you can actually turn the thermostat down.

Safety

Follow the manufacturer's instructions, check cables and fabric regularly and replace the blanket if it is damaged or very old. Safety guidance generally advises against use with babies and young children or with people who cannot adjust it or sense heat properly. Do not leave heaters on unattended and keep them away from curtains and fabrics.

Limits of the calculator

The calculation uses the average power you enter and does not consider thermostats, on-off cycles or different settings. It only compares electric appliances: for gas boilers or heat pumps the cost per hour of heat is different and should be worked out separately.

Frequently asked questions

How much does an electric blanket use?

A single blanket usually draws a few tens of watts: at 60 W for 4 hours a day over 120 days it uses about 29 kWh, around 8.64 with energy at 0.30.

Is an electric blanket cheaper than a heater?

Almost always: with 60 W against 1500 W it costs 4% of the heater for the same hours.

What does an hour of electric blanket cost?

With 60 W and energy at 0.30 per kWh, about 0.018 an hour; a 1500 W heater costs about 0.45 an hour.

Why does a blanket use so little?

Because it warms only the person, by contact, instead of heating all the air in the room, which escapes through walls and windows.

Can a blanket replace heating?

No: it only warms the person using it while sitting or lying still. It works best combined with slightly lower heating.

What power should I enter?

The average power: many blankets heat on high for a few minutes and then stay on low, so they use less than their rated power.

How quickly does an electric blanket pay for itself?

If it really replaces hours of heater use, often within the first season: in the example it saves over 200 a season.

Are electric blankets safe?

If used as directed and checked regularly. Guidance generally advises against use with babies, young children or people who cannot adjust them.

Can I leave it on all night?

It depends on the model: follow the manufacturer's instructions. Many models have auto shut-off and low settings designed for overnight use.

Does it work for heated throws?

Yes, the calculation is the same: enter the throw's power instead of the blanket's.

What if my heating is gas?

The calculator compares electric appliances. With gas or a heat pump the cost of an hour of heat is different and should be estimated separately.

Does it work in any currency?

Yes. Enter the energy price in your currency; the verdict is based on the ratio between powers, which does not depend on the currency.