Just in case anyone was in any doubt of the importance of windspeed to a windfarm's power output, here is exhibit A.

Babcock & Brown Wind Partners (as listed on the Australian Stock Exchange) said it had generated 100 gigawatt hours less than forecast and generated $10 million less revenue mainly because of the delays in three Spanish wind farm acquisitions, but also because the wind did not blow in May and June.

Low windspeed years can always happen, which is why global diversification of wind assets is so vital to consistent returns.

The wind is always blowing somewhere in the world.