The cost of balancing Great Britain’s power grid has soared to near-record highs of almost £50m a day after windfarms were turned off due to bottlenecks in transmitting power around the country.
The grid operator paid £47.9m on Wednesday to turn windfarms off in areas with an oversupply of electricity and turn gas plants on in areas where supplies were tight.
The costs, which are levied on to household energy bills, included a £1.6m payment for one half-hour period, and were some of the highest recorded since the early months of the Ukraine crisis in 2022.
They add to the growing costs of balancing the grid, which reached a total of £505m in September alone, the highest monthly cost ever recorded, and are expected to reach £3.2bn over the next year.
The costs underline the growing concerns over the pace of Great Britain’s £150bn power networks upgrade, which is failing to keep up with new renewable energy projects being connecting to the grid.
Overall, windfarms and hydro power plants with about 9 gigawatts of capacity were paid to not generate on Wednesday, according to consultancy LCP Delta, enough to power more than 8m typical households.
Instead, the grid operator was forced to pay for a string of gas and biomass plants to fire up and bought more electricity imports from Europe via high voltage subsea power cables.
The record costs have come to light days after the National Energy System Operator was forced to call for “last resort” emergency assistance from its counterpart in France, which agreed to send last-minute power supplies to the UK on Monday and Friday last week.
“The system overall wasn’t tight in terms of power supplies,” said Shivam Malhotra, the head of power trading at LCP Delta. “It’s the age-old story of a lack of infrastructure to transport power to where it’s needed, leading to lots of windfarms being turned off.”
Typically, windfarms in Scotland are paid to turn off because there is not enough high voltage cabling connecting the region to areas of growing electricity demand in the south of the country.
“To resolve the energy needs in the south of the country Neso had to use one of their last resorts. It’s quite surprising for this time of year,” Malhotra said.
Neso was approached for comment.
During the summer Neso faced severe grid challenges when a high pressure heat dome led to a drop in renewable energy output and surging electricity demand to power air conditioning and refrigerators.
Neso was forced to bring in independent investigators to look into whistleblower claims that its staff were involved in a cover-up of a near-blackout during record high temperatures in late June.
The accusations, which were raised in parliament last week by the Conservative shadow minister Claire Coutinho, include claims that senior bosses at Neso were “risking blackouts to protect Neso’s reputation”.
Fintan Slye, Neso’s chief executive, told an industry conference on Wednesday that there will be “lessons to be learned” coming out of a review into that period by the industry regulator Ofgem.
Asked how he thought Neso handled the situation, Slye said: “Through that period, no customers were disconnected [and] frequencies stayed within statutory limits. But undoubtedly, it was a really challenging period for the system and right across Europe we saw power systems … under strain.
“I think the control room and teams that were in it did an absolutely superb job managing what was a really difficult situation through the week.”
