Six wind farms were given six-figure payments to switch off their turbines because the Scottish grid network could not absorb all the energy being produced, it emerged today.
Research by the Renewable Energy Foundation (REF) found energy companies were paid a total of £900,000 for stopping the turbines for several hours between April 5 and 6 this year.
The REF said some of the payments were as high as 20 times the value of the electricity which would have been generated if the turbines kept running.
The National Grid makes constraint payments to power stations that agree to stop generating in order to stabilise the network.
It happens when the grid system or a section of the system is unable to absorb all the electricity being generated.
The largest payments were made to Whitelee wind farm in East Renfrewshire, which was given over £300,000 in April 2011, and Farr wind farm, south of Inverness, which received over £260,000 in the same month.
Dr Lee Moroney, Planning Director for the REF, said: “The variability of wind power poses grid management problems for which there are no cheap solutions.
“However, throwing the energy away, and paying wind farms handsomely for doing so, is not only costly but obviously very wasteful.
“Government must rethink the scale and pace of wind power development before the costs of managing it become intolerable and the scale of the waste scandalous.”
The National Grid said the grid had overloaded because high winds and heavy rain in Scotland on April 4 and 6 produced more wind energy than it could use.
A spokesman said it had happened on one other occasion, adding that making the payments were “the most cost-effective way to balance supply and demand”.