The cost of switching off wind turbines jumped to a record last year as the UK’s cable network and storage capacity struggled to keep up with the amount of electricity generated.
Bill-payers were forced to shell out £507m last year alone to cover the costs of switching off turbines when it is too windy for the grid to handle and bringing on gas supplies instead.
It is a 70pc jump on a year ago, according to the consultancy LCP, which calculated the figures.
Turbines are asked to turn off if they are generating more electricity than is needed locally at the time or the electricity grid can carry to other areas of demand.
The total figure is mostly made up of the cost of procuring gas-fired and other supplies instead of using wind, with gas prices soaring since last August as a result of global shortages.
However, the figures highlight the complications of managing the electricity grid at a time of more varied sources of energy including more intermittent sources such as wind and solar power.
It comes as soaring household energy bills mainly due to high gas costs have helped trigger the deepest cost of living squeeze in a generation.
The Government has introduced a windfall tax on oil and gas producers to help ease the pressure on households, and is considering extending this to electricity generators.
Chris Matson, of LCP, said growing wind power was essential for climate targets and energy security.
But he added: “And yet because investment in the infrastructure needed to support this expansion has not kept pace, wind curtailment is costing the consumer and the environment. Every pound spent on curtailing wind power is a pound wasted.”
LCP calculated the figures in a report commissioned by FTSE 250 power company Drax, which is looking for Government support to extend its hydropower station in Scotland that can act as a giant battery to store electricity.
LCP said long duration storage such as Drax’s hydropower project was a “particularly attractive” way of dealing with the current problems, but stressed that such measures “would not necessarily mean that all of the cost of curtailment can be avoided”.
Britain’s wind power industry has grown rapidly over the last decade, with 25.7GW installed capacity now compared to about 5.4GW in 2010, enough to provide power for about twenty million homes.
Much of this is located in Scotland owing to its weather as well as available space both on land and around the coast. However, the cables that transport electricity around the country can only handle so much at a time, meaning that wind farms are paid to cut output when needed.
These costs, in addition to those that ensure electricity supply and demand is matched every day, are met by National Grid but ultimately recouped via a levy on consumer bills.
LCP said that wind farms were paid a net £78m to turn down 2021, while £429m was paid to gas-fired and other generators to provide power at times when wind turbines have been asked to switch off due to local constraints.
“In many instances [..] wind generation must be turned down in certain locations and high-carbon gas must be turned up in other locations,” it said.
LCP estimates that Scottish wind power accounted for 94pc of the total amount of wind generation curtailed in 2020 and 80pc in 2021.
Many more wind turbines are set to be built in Scottish waters following a recent leasing round. The Government wants to increase offshore wind capacity five-fold to 50GW by 2030.