A WARNING has been given that blaming calm weather for reduced power generation from wind farms could hamper investment in renewable energy.

A summer of low wind has led to opponents of wind farms to claim they are ineffective and expensive but experts believe poor performance may be due to other reasons such as faulty equipment.

If not addressed, a trend for over-attributing low production solely to wind resource could be damaging to clean electricity output across European wind farms, according to Clir, the leading provider of digital asset performance technology for the wind industry.

Calm weather all over Europe last summer has helped drive peak hour power prices to their second highest level since 2018.

Energy companies, including SSE in the UK and Orsted in Denmark, reported their lowest wind speeds for two decades, while the pressure to deliver on production targets was at an all-time high.

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Energy consumption data for July to September showed renewable generation in the UK was down 17 percent on the same quarter last year. It is a sharper drop than in April to June when it fell 9.6%.

It has been driven by a huge 30% drop in wind generation which was substantially below the 10-year averages. It too is a sharper drop than in April to June when there was a 14% decline.

However, Clir claims that if low wind power generation is attributed solely to wind resource, there could be a significant impact on supplies of clean power to the grid as a focus on how many turbines are turning rather than how much energy they are producing may be preventing the detection of faults in the equipment.

“In the instance of lower power generation, it’s easy to apportion sole blame to wind resource,” said Andrew Brunskill, director of data science at Clir. “But there could be a myriad of other factors affecting project underperformance – ranging from incorrect yaw or pitch settings, or unanticipated environmental factors.

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Although modern software can identify low wind periods, Brunskill said its true value was in its ability to delve into the root causes behind wind farm underperformance irrespective of wind levels.

“We know that significant marginal gains can be made by immediate reporting and acting on equipment issues to optimise wind assets,” he said.

“However if we continue to place blame for lower performance solely on wind resource we’re collectively missing a huge opportunity to increase wind energy contributions to the European power mix and the underlying value of projects and portfolios.

“We are working with site operators to identify and resolve issues which in many cases are attributed to ‘low wind’ rather than wider inefficiencies.”