From Root River Energy's Fall 2010 Newsletter....
Wind researchers are constantly preoccupied with trying to make wind turbines more efficient and reliable. The more efficient the turbine, the fewer we need to build, the less land they take up, and the more easily they can be integrated into the electrical grid. By building a better turbine, we can make it more practical to use renewable energy. Based on a new report from the US Department of Energy, the 2009 Wind Technologies Market Report (WTMR), we’re making progress on this goal. The report says that by building turbines with higher nameplate capacities (the maximum output a turbine can produce) and larger rotor diameters (the diameter of the circle traced by the turbine blades as they rotate), we’re starting to create turbines that can operate efficiently at low wind speeds.
These turbines have the advantage of being able to deliver power even when the wind isn’t gusting as strongly as usual. Another factor making wind farms more reliable is that the average size of a wind farm is steadily increasing. The WTMR finds that the average U.S. wind farm constructed in 2009 had a capacity of 91 MW, higher than any other year on record except for 2007. Larger wind farms have less variability in electricity production between high-wind and low-wind periods, making them easier to incorporate on the grid. As more wind farms accumulate in an area, the variability in electricity production decreases more and more.