Worst year ever for wind farm energy due to drop in wind speeds 

Wind farms produced less power than ever last year despite an increase in the number of turbines, new annual energy statistics show.

The disappointing figures come after the South West failed to meet its renewable electricity target last year and have sparked renewed criticism of controversial onshore plants.

Despite being designated the first Low Carbon Economic Area in England, the region fell short of the 611MW output target.

Average output from Britain’s 275 onshore wind farms fell to the lowest level on record, according to figures from the Department of Energy and Climate Change (DECC). The amount of electricity generated from 3,000 land-based turbines, including about 100 in Devon and Cornwall, fell by 7.7 per cent in 2010. However, the decline per turbine was much greater because the overall capacity of onshore wind farms grew by 14 per cent last year.

Huhne visited a north Cornwall site which has doubled its output capacity by replacing ten turbines with four larger units.

During the reopening at Delabole, Mr Huhne described wind farms as “a key part” of the nation’s energy future.

Critics have questioned the Government’s decision to rely heavily on the sector for future needs.

Campaigns advisor and co-ordinator Alan Nunn, of the Realistic Energy Forum South West, said poor performance after a drop in wind speeds highlighted the unreliability of turbines.

Mr Nunn insists that, despite concerns after of the Japanese reactor “meltdown”, the “only real way forward is nuclear” and says onshore wind generation is “a total con” and “a farce”.

“To achieve maximum power you need a wind speed of 33 miles per hour and that only happens for one per cent of the year,” he added.

“The average is more like 15 to 18 miles per hour, which only gives half the output power, and it is unreliable because of the rise and fall of wind speeds. Out in the ocean we get more out of them but land-based turbines are inefficient and operate at the expense of residents’ health and property prices.” Onshore wind farms tend to produce less energy in winter when the demand is highest because freezing conditions mean low wind.

The DECC’s annual Energy Statistics, published on Friday, showed that despite onshore wind capacity increasing by 14 per cent (476 MW) in 2010, wind farms operated at only 21.4 per cent of their maximum potential capacity, compared with 27.4 per cent in 2009.

The report said: “Ten months of 2010 saw lower wind speeds than the ten-year average.”

The Government is offering generous subsidies to wind energy firms as part of a strategy to produce a quarter of Britain’s electricity by 2020. Opponents of wind farms say this could lead to power cuts during prolonged periods of low wind.

On December 7 last year, when the demand for electricity was at its fourth highest level recorded, wind farms produced only 0.4 per cent of the power needed by the country.

The Renewable Energy Foundation (REF), which lobbies against overreliance on wind energy, thinks the decline in output could partly be because the industry has already developed the windiest sites and had begun expanding in less reliable areas.

John Constable, director of policy at the REF, said: “The Government seems to think it can walk up to the shelf and buy green energy, but we are still learning how variable it is.”

RenewableUK, the wind industry trade body, said that it was important to look at long-term averages for wind speed and it would be wrong to alter policy on the basis of one poor year.

It said an alternative analysis of the energy statistics showed a “particularly significant” 24 per cent increase in electricity when comparing the fourth quarter of 2010 with 2009.

Alex Murley, RenewableUK’s head of technical affairs, said: “In terms of Quarter 4 2010 all indicators point to the fact wind delivered a record contribution of electricity to the grid, both 20 per cent higher than Q3 2010 and 24 per cent higher than the comparable Quarter of 2009.

“The message from the statistics is clear: wind is becoming the dominant renewable technology in terms of consistent growth and units delivered to consumers.”