It may often seem that wind power is still in its infancy, or at least its childhood, adolescence (or some other metaphor implying there's still lots of growth and development but not nearly doing all that it could and should), but commercial wind farms have been around a good long while. An example: As BBC News reports a 20 year old wind farm off the coast of Cornwall, UK has just gotten a refurbishment and relaunch.
The Delabole wind farm, originally launched in 1991 with ten 50' tall turbines, was the UK's first. It now consists of of those original ten plus four more 325' turbines, bringing Delabole's installed capacity to 9.2 MW.More on Wind Power:
China Beat US in Offshore Wind, Europe Still Trounces Everyone Else in Solar Power
Why China and Europe Invest More in US Wind Power Than the US Does