The National Grid has announced it will pay customers to use less electricity on Wednesday evening as part of its blackout-prevention scheme, as the UK faces more cold weather.
It is the first time it has activated a Live Demand Flexibility Service event this winter, after a test event earlier in November.
The move comes as the Met Office issued a number of yellow weather warnings for snow and ice along the East coast of England and Scotland for the rest of the week.
The National Grid reassured customers electricity supplies are not at risk and they should not be worried.
A spokesperson for the National Grid ESO (electricity system operator) said: "These are precautionary measures to maintain the buffer of spare capacity we need."
Who is eligible for the payments?
Households with a smart meter and business sites with half-hourly metering can take part in the Demand Flexibility Service.
Customers don't have to go without electricity at all during the event to be eligible for payments, they just have to use less than they usually would.
Which energy companies are taking part in the scheme?
A lot more energy companies are taking part in the scheme this winter than last year when the scheme was launched, when only three providers were participating.
This year's list for households include companies like British Gas, EDF, Equiwatt, Octopus Energy and Utilita.
A full list of registered providers, including those for businesses, can be found on the National Grid ESO website.
When does the scheme run?
Customers are being asked to reduce their electricity usage during peak time on the evening of Wednesday November 29, between 5pm and 6.30pm.
How much could you be paid?
The payments will depend on how much electricity customers usually use during the time period, how much less they use during the event, and how much their provider offers for the service.
The National Grid passes the funds for this scheme on to participating energy companies and it is up to them to decide how it is passed on to customers.
How do I sign up?
Customers can register for the scheme through their energy supplier.
The National Grid ESO says companies should contact customers if they are taking part in the scheme this year.
Participation in the scheme is completely voluntary and there is no penalty if you sign up and don't reduce your usage.
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