The most efficient farms are in parts of Scotland and Wales
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The government is paying hundreds of millions of pounds to subsidise wind farms that are not economically viable, it has been claimed.
Environmental consultant Michael Jefferson says farms are being built in areas of England, Wales and Scotland without enough wind.
But the British Wind Energy Association (BWEA) says the claims are "nonsense".
It says subsidies are not paid for the building of plants, only per unit of electricity to the National Grid.
Chief executive of the BWEA Maria McCaffery said: "Nobody in their right mind, not a developer and not the government, would support the building of a wind farm where the wind speeds are not high enough to generate a viable amount of electricity.
"It's absolute nonsense."
'Development pressure'
The government is trying to reach an EU target of 20% of all energy from renewable sources by 2020.
But Mr Jefferson told BBC Radio 4's Costing the Earth programme that financial incentives - part of the Renewables Obligation Certificate Scheme - were encouraging firms to site wind farms badly.
He said some companies were exaggerating the amount of wind energy a development would supply, particularly in areas of England with relatively little wind like the Midlands and Home Counties.
He claimed that in these areas the load factor - the average amount of wind a particular spot gets in a year - was not high enough to be viable.
"We should be putting our money where the wind is and that is quite often not where the development pressure is," Mr Jefferson added.
But Ms McCaffery refuted the idea, saying subsidies were not paid just for building a plant and load factor was "irrelevant".
"The only pertinent figure is the amount of electricity actually supplied and there is a fixed amount of subsidy per unit of energy. You are only subsidised for what you produce."
Mr Jefferson has links to the World Renewable Energy Network, but the organisation stressed that he was expressing his own views and not speaking on their behalf.
Volatility
Engineering consultant Jim Oswald told BBC Radio 4 that many turbines were underperforming because wind speeds in Britain were too variable.
"The volatility thing is a bit like driving your car and I say to you, 'OK, here's a green car, it uses absolutely no fossil fuel but you can only use it when it's windy," Mr Oswald said.
But Ms McCaffery said Britain was windier than any other country in Western Europe and most farms would be generating some electricity for 85% of the time.
She admitted that not every wind farm could be located in areas of highest wind speed, but instead the industry had to identify areas where wind speeds were "good enough" to be economically viable.
Both Mr Jefferson and Mr Oswald criticised the fact that some wind farms in remote areas like northern Scotland were sitting idle because they were not connected to the National Grid.
But Ms McCaffery said the connection backlog was being tackled and in the meantime these plants were not receiving subsidy.
'Power swings'
Mr Oswald said variability in wind speed could lead to major power failures in future if the system was not redesigned.
"It's the power swings that worry us. Over a 20-hour period you can go from almost 100% wind output to 20%."
Energy Minister Malcolm Wicks insisted that wind energy was an important part of Britain's energy mix for the future.
He said the government was encouraging more offshore wind farms combined with tidal and marine power plants.
Wind power is Britain's fastest growing source of renewable energy, but still meets less than 0.5% of our electricity needs.
Costing the Earth is broadcast on BBC Radio 4 on Thursday 30 August at 2100BST.
HOW WIND FARMS WORK
1. Blades turn shaft inside nacelle - a box at top of turbine. Generator inside nacelle uses magnetic fields to convert rotational energy into electric energy
2. Transformer (in this case, offshore) converts the 700V generated into about 33,000V for distribution and sends it to substation
3. National grid distributes power around the country
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