the vagaries of wind power were highlighted once again, when it was confirmed that last month the National Grid paid six Scottish windfarms to stop producing electricity.
Windy weather for a short time in early April meant that the wind farms were producing so much electricity the National Grid could not absorb it.
During the very cold spell in November/December last year the reverse happened and despite demands on the National Grid going up as people tried to keep warm in temperatures that rarely rose above freezing for several weeks wind farms produced very little electricity because the high pressure responsible for the cold spell was combined with hardly any wind.
The National Grid spend £280 million balancing electricity supply and demand annually and Stewart Larque, a Grid spokesman, said: “One of our key roles is to balance supply and demand for energy.
“On the evening of April 5 and 6, the wind in Scotland was high; it was raining heavily, which also created more hydro energy than normal.”
A spokesman for the Department of Energy and Climate Change said that the incident was ‘unusual’ and that they need greater power storage facilities.
“In future we need greater electrical energy storage facilities and greater interconnection with our EU neighbours so that excess energy supplies can be sold or bought where required,” he said.
The National Grid is reported to have made payments of up to £300,000 to the six Scottish wind farms - and research by the Renewable Energy Foundation (REF) estimates that the National Grid payments are 20 times the value of the electricity that would have been generated if the farms had kept running. The National Grid made payments of over £900,000 during that period to stop wind farms across the UK producing electricity for a short period.
The Scottish wind farms paid to stop work were: Whitelee windfarm, East Renfrewshire; Farr windfarm, south of Inverness; Hadyardhill in South Ayrshire; Blacklaw windfarm in Lanarkshire; The Millennium windfarm in the Highlands; and Beinn Tharsuin, north of Alness.
According to Ray Noble of the Renewable Energy Association (REA) this incident highlights the problems inherent in the Government’s present policy concerning renewable energies.
“It is vital that Government policy harnesses all the renewable technologies to cover all the various weather effects we encounter in Britain,” he said.
“2010 was a poor year for wind turbines (because of lack of wind) and a poor year for hydro (because of the lack of rain) and now, after one night of wind and rain, we have too much electricity. The Government has turned its back on a structured solar industry but solar is predictable and more reliable than either wind or hydro. Photovoltaic (PV) generation works on light and annual light levels vary by less than 5% therefore the annual generation is predictable,” he said.
Last month, the Department of Energy and Climate Change announced a proposal that would cut the support (through feed-in-tariffs) for medium sized solar developments by 72% this summer. According to both the REA this cut would effectively end the development of solar in Britain as a major player in the country’s future low-carbon generation plans.
“Wind turbines, because of planning issues, are now being built further and further away from urban conurbations with much having to go offshore; this results in having to use the inefficient main grid to transfer the electricity to the point of use and in doing so you can lose up to 8% in transmission losses,” explained Mr Noble.
“Solar can be onnected to the local distribution system and avoiding transmission losses,” he said.