Do Microwaves Use A Lot Of Electricity?

Do microwaves use a lot of electricity?
Do microwaves use a lot of electricity?

Microwaves have become so common place in our kitchens that we don’t ever question their usefulness and efficiency. But as you try to find savings around the home or perhaps look for a new microwave you may wonder – do microwaves use a lot of electricity?

The short answer is not really. Unless you have an industrial sized microwave in your kitchen that is constantly in use then your energy usage will amount to a few pounds every year.

There are a number of factors that will determine how much electricity is used by a microwave.

Power Rating: The first factor is the power rating of the microwave. Most microwaves will range between 600 to 1200 watts in power.

Length of Time In Use: The longer you use your microwave, the more electricity it will use. Microwaves also use some energy when they are in standby mode i.e. plugged into the wall but not actually in use.

Power Level You Use: The power level you set when using your microwave will also play a part in the amount of energy used. Most microwaves however, will have options to vary the power level (e.g. 30%, 50% power etc).

The majority of microwave users only ever use them to heat up power and we can imagine a significant number will use the quick setting which heats items up at full power.

When you use your microwave at full power you’ll consume the rated power of the machine. The rated power of your microwave will typically be displayed in a diagram on the front door.

If you’re shopping around for a new microwave you should be able to find the power rating in the product description.

How Much Does It Cost To Use A Microwave?


To see how these 3 factors come into play lets take imagine you opt to buy an 800 watt microwave, that you’ll use for 10 minutes every day for reheating at full power:-

Power Rating: 800 Watts

Length of Time In Use: 10 minutes every day

Power Level You Use: Full power, 800 Watts

Electricity cost is measured in kilowatt hours (kWh). The average rate for kWh in the UK is 14.37p

10 minutes of usage every day equates to roughly 0.17 hours of use each day.

With the parameters above the microwave will cost you less than 2p to run per day (1.92p to be exact), around 58p per month and about £7 per year. So do microwaves use a lot of electricity? In the grand scheme of things – not a whole lot.

Table 1 – Do microwaves use a lot of electricity? Cost of running a microwave for 10 minutes every day at 14.37p per kWh

Power RatingCost Per MonthCost Per Year
1200 Watts88p per month£10.51 per year
1000 Watts73p per month£8.67 per year
900 Watts66p per month£7.88 per year
800 Watts58p per month£7.01 per year
700 Watts51p per month£6.13 per year
600 Watts44p per month£5.26 per year

Do Microwaves Use Electricity When They’re Not In Use?

As well as using power whilst it is cooking, your microwave will also consume power when its plugged into the wall which may surprise some.

Remember also that some microwaves have a digital clock display whenever they are not in use.

The amount of power that’s used by microwaves can often vary but 5 watts is a useful guide. Most people will leave their microwave plugged into the wall 24 hours a day.

At 14.3p per kWh this equates to roughly 52p per month and £6.29 per year. Whilst this is not a huge amount if you have a 900 watt machine or lower, it comes pretty close or exceeds the amount of power you might typically use when it’s actually cooking.

So it’s worth considering whether it makes sense to unplug the microwave after use. If you would rather not do that, you could also look for microwaves with an eco mode which use less power during standby. These typically work by switching off the digital display when they are not in use.

Is A Microwave More Energy Efficient Than An Oven?

As we’ve seen microwaves don’t use too much power relatively speaking which makes them quite an efficient choice for cooking. Let’s take a look at some of the other benefits of microwaves that makes them more energy efficienct than conventional ovens.

They Don’t Heat Up Your Dishes

One of the reasons why microwaves can heat up your food so quickly is that they do only heat up your food and not the dish its on. This is because in actual fact the microwaves heat up water molecules inside your food. This heat is then transferred within your food resulting in food that’s heated quickly from the inside out. This contrasts with traditional ovens that need to heat up first before they can start to cook your food from the outside in. This is why recipes call for pre-heating your oven well before you actually place your food inside.

They Operate Faster

As alluded above, because conventional ovens have to be pre-heated to get them to the temperature you need for your recipes it can take ages to go from start to finish. With a microwave, you don’t have this problem as you go from 0% to 100% power straight away. This means you spend far less time heating and cooking your food. As we’ve already seen the less time you spend cooking, the less electricity you are going to use.

Do Microwaves Use A Lot Of Electricity?: Let us know your thoughts.