Unusually low wind conditions encompassing wide swaths of land have led to severe generation shortfalls at many U.S. wind farms.
During the first three months of the year, output at many U.S. wind farms – particularly those in the western U.S – are off nearly 50% from forecasted estimates.
A January 2015 wind resource map from Vaisala confirms the lack of wind at the beginning of the year. The map confirms that that wind speeds were off 20% from their normal January averages. And within some western U.S. locations, Vaisala confirms that wind resources may be off as much as 45% from their long-term January averages. To view the map, click here.
‘Below-average wind speeds observed at wind projects across the U.S. in early 2015 match what we are seeing in global datasets,’ confirms Pascal Storck, global manager of energy services at Vaisala. ‘In our view, these anomalies are nothing unusual or outside the range of what we would expect when looking at the long-term data.
‘From our long-term database of multiple global models, we have observed periods of over – or underperformance that can last for several years and, in some cases, as long as a decade.’
Meteorologist Ron Nierenberg has a more obvious reason for the wind shortfall: a warmer than expected winter.
‘The past winter [in the Western U.S.] was extremely abnormal, with temperatures way above normal and snowfall way below normal,’ explains Nierenberg, who is based out of Camas, Wash. ‘While Boston got slammed, we have not really had any winter out here. No winter, no wind. It's that simple.’
Nonetheless, not every North American region suffered from a lack of wind.
For example, while wind output was at a premium in the West, the Vaisala map shows central Canadian winds clocking in at 20% above the normal average for January. Further, Montana, North Dakota and South Dakota – and much of Minnesota and Nebraska – experienced wind speeds 5% to 10% above normal and patches of 20% above normal.
While output is logically a concern among owners and operators, the lack of generation is also beginning to become an issue for wind farm investors that depend on output to generate bottom-line performance. As such, some investors could begin to question the rationale behind the shortfall.
Vaisala's Storck says wind conditions are variable and, therefore, subject to change. As such, Storck encourages anxious investors to take the long view when assessing the relative merits of wind farm performance – or underperformance.
‘For wind investors, these anomalies underscore the importance of having a long-term view of weather and climate when drawing conclusions about future performance based on past observations.’Â
