Is electricity cheaper at night in the UK? Economy 7 explained

You can get cheaper electricity at night with an Economy 7 meter - but it can come with financial and safety risks if not use correctly

Night scene of houses in Cambridge
(Image credit: Getty images)

Cheaper electricity at night is made possible by Economy 7 meters which – if used correctly - can help you cut your bills. But be warned, it can be dangerous to run appliances without supervision overnight and if you get your timings wrong it could cost you money too. 

Setting your alarm and getting up in the middle of the night to run your dishwasher, washing machine or tumble dryer might sound drastic but cash strapped households need ways to save on energy bills right now - from ditching ovens for air fryers and microwaves to working out if it’s cheaper to leave the heating on low all day and finding the best time to put your central heating on.

Here we explain how you can unlock cheaper energy at night - and the risks.

Is electricity cheaper at night? - Economy 7 explained

With standard electric meters - you pay the same price for each unit of energy (kWh) you use regardless of the time of day or night.    

But if you have an Economy 7 meter - typically installed in houses reliant on electricity for both heating and hot water instead of gas -  can help you save on your electricity bill because it unlocks cheaper overnight rates.

Under the energy price guarantee – which kicked in on 1 October – you pay 34p per unit (kWh) of electricity based payment by direct debit. But in some cases Economy 7 could be around 10p per unit cheaper with night time rates.

Kevin Mountford, co-founder of savings platform Raisin UK (opens in new tab), says: “If you work night shifts or find yourself sleeping during the day and then doing chores at night, this tariff will save you money.  It’s also ideal for electric car owners who will charge their electric cars in the evening”.

How Economy 7 energy works

With Economy 7 - you pay two different rates for the electricity you use – one during the day and a cheaper one for an overnight period of seven hours.

“Some Economy 7 plans charge a significant amount over the standard night rate for any electricity used in the day, which can cancel out the benefits of the cheap electricity you get at night”, says Ben Gallizzi, energy expert with Uswitch (opens in new tab)

“As a general rule of thumb you would need to use more than 40% of your electricity at night to make Economy 7 cost-effective”.

There’s no universal fixed time when the cheaper overnight rates kick in according to Uswitch, and it can depend on your supplier along with where you live.  

Generally the cheaper ‘night’ rate can run from 11pm – 6am or midnight to 7am or 1am to 8am.

“It’s important to check with your energy supplier to work out what the Economy 7 hours are, as if you use electricity out of the 7-hour window, you will be paying more”, warns Kevin Mountford.

It is also worth knowing Economy 7 meters won’t adjust automatically when the clocks go forwards or back. So check what you need to do with your supplier as the clocks go back one hour on 30 October at the end of British Summer Time.

But be warned - it can be dangerous to run some appliances overnight

It might be cheaper to run appliances overnight if you’ve got Economy 7 – but experts warn that you need to consider the safety element of doing this while you’re tucked up in bed.

Emily Seymour, Which? (opens in new tab) Energy and Sustainability Editor, said: "Major appliances such as washing machines and dishwashers should not be used when you're asleep, or out of the house. Anything with a high wattage or a motor runs a fire risk and should not be left unattended”.

And Ben Gallizzi says, “Leaving appliances running overnight means you are less likely to know when something goes wrong like if they catch fire. This is why firefighters advise people to turn off what they can overnight”.

Can you always save money with Economy 7?

There’s no guarantee you’ll automatically save money as reduced energy bills will depend on your habits and on the flipside – the cost per unit can be more expensive during daytime.

“Based on a Bulb economy 7 tariff, the day rate for electricity is 34.7876p per kWh, whilst the night rate is 24.234p per kWh. The average washing machine is 2,100 watts, which is equal to 2.1 kWh, meaning it would cost 73p per cycle to wash during the day, whilst washing during the night would only cost you 50p”, says Kevin Mountford.     

Based on these calculations – running your washing three times a week at night instead of during the day could save you over £35 a year.

If you want to benefit from cheaper overnight rates with Economy 7 -  but don’t want to wait up to start your washing at 11pm or later – the easy option is to buy a plug in timer.  

This means you can pre-set appliances to come on at fixed times and you can pick these up from around £6.99 at Screwfix (opens in new tab) or buy a set of three at Argos for £12.99.

Can you save money using appliances ‘off peak’ if you’re not on Economy 7?

Octopus Energy (opens in new tab) is running a flexible energy service for domestic customers on smart meters along with 5,000 businesses who can get paid if they reduce their energy usage at certain peak times.

Saving Sessions means for each unit of energy saved, compared to normal usage - Octopus will pay an average of £4 per kilowatt hour.

This could save customers around £100 over the course of the Winter from November to next March.

Related articles

Sue Hayward

Sue Hayward is a personal finance and consumer journalist, broadcaster and author who regularly chats on TV and Radio on ways to get more power for your pound.  Sue’s written for a wide range of publications including the Guardian, i Paper, Good Housekeeping, Lovemoney and My Weekly. Cats, cheese and travel are Sue’s passions away from her desk!