Even relatively recent growth forecasts are being updated. The Global Wind Energy Council now says 172 GW will be reached by 2010 and 240 GW by 2014. Since capacity has been doubling every three years or so for some time now, the expectations are realistic. An installed capacity of 240 GW of wind delivers around 450 TWh of electricity, roughly the volume consumed in France and just under 3% of current global electricity use.
Key wind turbine component suppliers are expanding production capacity a fast as they can. Lack of gearboxes is a serious bottleneck, but one leading supplier, Hansen, says it will be making enough for 14 GW of wind turbines a year by 2012. In the expectation that at least five other gearbox makers have similar expansion plans, gearboxes for 70 GW of wind turbines a year will be on the market. If they all go to new machines, the indication is that the global market's current 25% growth rate will continue -- and global installed wind power capacity by 2012 could even approach 300 GW.