Wind farm myth blown away by research

Another myth about wind farms has been busted. Questions have been raised about the efficiency of ageing wind turbines, with some studies suggesting that efficiency decreases by a third after just 10 years of operation - making wind power an unattractive economic option.

But a new study has found that turbines will last a full 25 years before they need to be upgraded. The study, conducted by Imperial College Business School, showed that the UK’s oldest operating wind turbines (built in the 1990s) are still producing three-quarters of their original output after 19 years’ operation - nearly twice the amount previously claimed. This output is comparable to the performance of gas turbines used in power stations.

The study also found that turbines built more recently perform better than earlier models, suggesting that newer designs could have a longer lifespan. The researchers believe their findings make a strong business case for further investment in the wind farm industry.

“Wind farms are an important source of renewable energy. In contrast, our dwindling supply of fossil fuels leaves the UK vulnerable to price fluctuations and with a costly import bill. However, in the past it has been difficult for investors to work out whether wind farms are an attractive investment,” said Dr Iain Staffell, co-author of the paper and a research fellow at Imperial College Business School.

“Our study provides some certainty, helping investors to see that wind farms are an effective long-term investment and a viable way to help the UK tackle future energy challenges.”

“There have been concerns about the costs of maintaining ageing wind farms and whether they are worth investing in. This study gives a ‘thumbs up’ to the technology and shows that renewable energy is an asset for the long term,” added Professor Richard Green, co-author and head of the Department of Management at Imperial College Business School.

The researchers drew on NASA data collected over 20 years in order to measure the wind speed at the exact site of each onshore wind farm in the UK. They compared this with actual recorded output data from each farm and developed a formula to calculate how wear and tear of the machinery affects the turbines’ performance.

Previous studies have only used the average estimates of nationwide wind speeds to determine the effects of wear and tear on wind farm infrastructure.

In the future, the team hopes to study newer wind farms over a longer period to determine if advancements in turbine technology means that they are degrading less. This could help the researchers to determine more accurately how long newer wind farms will last so that they can calculate their potential long-term economic benefits.

The study was funded by the Engineering and Physical Science Research Council and by the Alan Howard Charitable Trust.