Thousands of customers with smart meters will be able to cook their Christmas dinner for free as the price of energy is dropped to 0p per kilowatt-hour.
Challenger supplier Octopus is cutting prices to zero between 11am and 3pm on Christmas Day for those on its Agile Tariff.
The deal uses smart meters to deliver real-time prices which are linked to publicly available wholesale prices of gas and electricity, which Octopus says means bills are more transparent.
The Big Six energy suppliers have been heavily criticised for being quick to pass on price rises but slow to give consumers the benefit when prices fall.
Octopus says its Agile tariff has also helped customers shift 28 per cent of their energy consumption to times when it is cheaper, and often greener.
The tariff allows customers to access dynamic pricing and use it to schedule smart devices, electric vehicles and chargers, to use energy while prices are lowest.
For Christmas Day, the algorithm that works out the price is being tweaked to give customers the free four-hour window to roast their dinner.
Earlier this month wholesale priced dropped below 0p and as a result, customers on the flexible tariff were paid to use energy.
Negative prices are becoming increasingly common as the renewable generation, which fluctuates in line with weather conditions, accounts for a rising proportion of the UK’s energy supply.
Renewables accounted for a record 33.1 per cent of the UK’s electricity supply between July and September.
The trend looks set to continue after a record amount of offshore wind infrastructure installed in 2018, with more than two gigawatts of capacity becoming operational, enough to power more than 2.3 million homes.
Greg Jackson, chief executive of Octopus Energy, said: “Smart tariffs will bring energy costs down by enabling customers to get cheap energy when there’s plenty of capacity in the system, and reduce demand at peak times.
“Redistribution of energy load on the grid is essential for our sustainable future.”
