Wind farms are producing less than a fifth of the electricity predicted, a study has found.
By Rebecca SmithPublished: 7:25AM GMT 22 Mar 2010
Some wind farms operating at just ten per cent of their maximum capacity, it is found. Photo: PA
The first detailed study of onshore wind farms has found that 20 of the sites produce less than 20 per cent of their maximum output with some producing less than 10 per cent.
Blyth Harbour in Northumberland is thought to be the least efficient wind farm producing just 7.9 per cent of its maximum capacity while Chelker reservoir in North Yorkshire operates at 8.7 per cent of its capacity.
The figures were compiled by lobby group Clowd using data collected by energy regulators Ofgem.
The best wind farms operate at about 50 per cent of their predicted maximum capacity while the majority produce around 25 per cent to 30 per cent.
Experts warned that subsidies for green energy are encouraging wind farms to be built in unsuitable areas.
Prof Michael Jefferson, of the London Metropolitan Business School, said developers 'grossly exaggerate' the energy producing potential of their sites.
He said: "The subsidies make it viable for developers to put turbines on sites they would not touch if the money was available."
Nick Medic, of Renewable UK, said Britain needed every bit of green energy it could generate.
Dustin Benton, senior policy officer at the Campaign for the Protection of Rural England, said although the organisation is in favour of renewable energy development such as wind power, it is vital that such schemes get 'maximum wind gain for our landscape buck'.
He added: "We should be putting wind farms in windy places but those are often the most beautiful landscapes and while we need to maximise the energy generated from wind farms we need to be realistic that there are limits.
"Renewable energy is important but carbon is not the only thing going on."
Mr Benton said the subsidy system for renewable energy projects was 'blind to the impact on the landcape and the importance of beauty and tranquility'.
The Government has announced plans to increase the number of wind turbines onshore and offshore over the next ten years.
The Conservatives have said they create tax exemptions for wind and nuclear power and launch a 'green bank' to invest in renewable energy.