Wind technologies have come a long way over the last 30 years, starting as custom-made amalgamations of farm machinery in Denmark and lab experiments in the U.S., and evolving to become the giant sentries of today's energy transition.
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According to the Department of Energy's 2009 Wind Technology Report, the average size wind turbine installed in the United States in 2008 was 1.67 megawatts (MW) and the average project size was 83 MW. While the average size of projects was down from 120 MW in 2007 due to the financial crisis, the figures were still larger than any other year. And in Europe, machines of 2 MW and above have accounted for more than half of total installations since 2005, according to Emerging Energy Research.
Any side-by-side comparison between “large” turbines of the past and present is astonishing. Take the Vestas 33-kW turbine released in 1979: With a rotor diameter of 10 meters, the machine looks like a toy compared with the company's new 3-MW, 112-meter rotor diameter turbine. And these newer 2 and 3-MW turbines are now being outdone by offshore machines in the 5-10 MW range produced by companies like Clipper, Enercon and REpower.
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As turbines reach 10 MW of capacity – and there are plans to go as high as 20 MW – he questions whether the industry needs to keep focusing on larger-size turbines. “The wind turbines don't really need to get any larger. They're big enough,” says Gipe. “There's sometimes this obsession with going bigger and bigger and it's not necessarily the size turbine that matters as much.”
Gipe says the most important innovations in modern wind turbines are features like variable speed generation and sophisticated power electronics that allow wind farm operators to regulate voltage. Without such systems, wind farms couldn't get as large as they are today.
http://www.renewableenergyworld.com/rea/news/podcast/2010/04/wind-size-matters-but-only-so-much20 MW offshore turbines? Wow now that would be something to see.
The larger turbines also have the hard to quantify advantage of producing less clutter.
Compare this:
To this:
Energy produced from the single 7MW turbine in the bottom picture is about double that of the cluttered mess of turbines in the top picture.
The 7MW E-126 is so large the image doesn't really show the true size very well. Look at the base of the tower for the door to get better understanding of the size. That turbine is 7MW peak power. 10MW peak power turbines are being designed now and according to the article they may eventually top out at 20MW.
Anyways check out the link lots of good stuff in there more than I could post in excerpt.