Half-price electricity with PeakSave Sundays

What are peak hours for using electricity?

Peak electricity hours tend to be in the morning when people are getting ready to head out to work and school and, in the evening, when they’re returning and making evening meals. Therefore, electricity use peaks at around 7am to 11am and then again from 5pm to 9pm.

Some energy tariffs allow consumers to save money by using electricity at off-peak hours. However, consumers on standard flat-rate or fixed energy tariffs pay the same for their electricity regardless of the time of day they use it.

Learn more about peak and off-peak electricity.

I signed up for PeakSave but haven't heard anything yet. What’s going on?

Thank you for signing up. It takes us a while to complete all our checks to make sure you're eligible and everything is ready. We'll let you know when we've completed these. It could take up to 10 days, so please bear with us.

How will you know how much electricity I use during PeakSave events and how will you calculate my credit?

Your smart meter will tell us. When you signed up to PeakSave, you agreed to let us take a smart meter reading every 30 minutes during PeakSave events so we can see exactly how much electricity you’re using.

During PeakSave events, any electricity you use is half price. You’ll pay for the electricity you use as normal, then we’ll credit your account or meter back with half of what you spent. You’ll pay your daily standing charge at your normal rate. This will not be discounted.

The amount you earn will depend on your energy tariff, unit rate and how much electricity you use during the events.

For every event, we multiply the number of units of electricity you use during the event (kWh) by 50% of your tariff unit rate after VAT (p/kWh).

For example:

• You’re a customer on our Standard Variable Tariff with an electricity unit rate of 24.50p/kWh (after VAT)
• 50% of your unit rate is 12.25p/kWh (after VAT)
• You use 5 kWh of electricity during the event
• 5 kWh x 12,25/kWh = 61.25p
• Your credit for taking part is 61p.

We round payments to the nearest penny. So if you earn a 55.5p credit, we’ll round this up to 56p. If you earn 55.4p, we’ll round this down to 55p.

I’m on a PeakSave tariff, can I still take part in regular PeakSave Sunday events?

If you’ve chosen our PeakSave Super Sunday tariff, you can't also take part in our regular PeakSave Sundays. But the good news is, you're automatically included in any special PeakSave bonus events, and you can still opt in to PeakSave Green Flex events to make the most of half-price electricity.

Do I need to be on a special tariff to take part in PeakSave Sundays?

No. Once you sign up for PeakSave, you can start saving money, no matter which tariff you're on.

Can I take part in PeakSave if I’m on your EV tariff?

Yes. If you’re registered for PeakSave already or have received an email from us inviting you to take part, you can get involved. But please be sure to check your tariff unit rates here if you plan to charge your electric vehicle during any of the events.

If you normally charge up overnight on a discounted rate and don’t top up again during the day, you may end up paying more to charge during a PeakSave event, even with electricity being half price.

Can I join PeakSave if I’ve got a prepayment meter?

Yes – we can now offer PeakSave to customers who prepay for their electricity. Sign up to find out about the PeakSave events and how you can make the most of them. We’ll let you know how to get involved in each event and how we’ll credit your meter afterwards.

What is the Demand Flexibility Service (DFS)?

Demand Flexibility Service is part of a national effort by suppliers and National Grid ESO to help create a better balance between supply and demand on the electricity grid. Relieving pressure on the grid at peak times will make sure everyone gets the electricity they need to power their lives. And as increased demand at busy times is often met by burning fossil fuels, it'll help the grid be greener, too.

PeakSave Winter was our first flexible energy trial. Nearly 200,000 PeakSavers took part between December 2022 and March 2023, and by making small changes to when they used energy, they collectively helped save 147 MWh of electricity at peak times. That’s enough to power 750,000 homes for an hour!

And last winter, we paid more than £2 million to our customers, with each customer on average saving more than £9 on their electricity bill.

Following the success of PeakSave Winter, we were excited to explore new ways our customers could save money through flexible energy use.

So, in June last year, we launched PeakSave Sundays – where customers enjoy half-price electricity for five hours every Sunday. Demand is low on Sundays, so we encourage our customers to use as much as they need between 11am and 4pm. Not only are they saving money, but also helping to make greater use of cleaner, greener energy by moving their electricity use to off-peak times.

And more recently we’ve introduced PeakSave Green Flex events. These reward customers for moving electricity use to times when there is likely to be lots of renewable electricity available in the UK’s energy system. This could be because of lower demand, large amounts of renewable energy being produced with windier or sunnier weather conditions, or both.

What if there are problems with my smart meter?

If there’s a problem with your smart meter that means we can’t see how much electricity you used during a PeakSave Sunday, we don’t want you to lose out and you’ll still earn a credit.

We’ll use average consumption during the five hours, based on available smart meter data from other PeakSavers, multiplied by your tariff unit rate to calculate your credit.

However, you’ll only be invited to take part in PeakSave Green Flex events if your smart meter is working properly and sending us regular readings.

What is flexible energy?

Energy systems need to continuously match supply to demand. This is called energy balancing. Flexible energy, or flexible demand, helps energy systems maintain this balance during periods of uncertainty.

In the past, this used to mean firing a generator up or down to meet the changing levels in energy usage. We used to hear how at half-time during the FA Cup Final, there was a huge spike in demand, as the nation reached for the kettle. Behind the scenes it meant power stations burning more coal (and sometimes even oil) to allow the country to have a simultaneous cup of tea. Now we can achieve grid flexibility through new methods, including energy storage, demand-side response (or flexible demand), and distributed generation (generating low carbon electricity at home or work, through solar panels or wind turbines, often paired with battery storage).

We’re exploring new ways we can supply cleaner, greener energy and help customers save money through flexible energy use, and PeakSave rewards customers for changing how and when they use electricity helping to reduce demand at its busiest. This helps to balance the grid and means we’re less reliant on fossil fuels to meet that demand, making our electricity more sustainable.

If you’d like to know more, see Centrica’s The Power of a flexible energy system.

Can I take part in PeakSave if I own roof-top solar panels and battery storage?

Yes. If you’re registered for PeakSave already or have received an email from us inviting you to take part, you can get involved.

Just bear in mind that your credits will depend on your electricity usage and generation, and how your battery is configured.

What if I move home or change supplier?

If you move home, you’ll need to re-register for PeakSave at your new address – even if you take your British Gas account and tariff with you.

If you have a gas account with us and switch it to a new supplier, you’ll still be eligible for PeakSave. However, if you switch your electricity account with us to a new supplier, you’ll no longer be able to take part.

If you switch your electricity account to a new supplier and we owe you a reward payment for a PeakSave event, this will go towards your final bill. Whatever’s left over, we’ll send to you by bank transfer or cheque, depending on how you pay your bills.

If you prepay for your electricity and we owe you a reward payment, we'll credit the amount directly to your smart meter. If, for any reason, we can't add it to your meter remotely, we’ll send a cheque or top-up code for the amount instead.