Equipment and products that enable us to use renewable energy instead of fossil fuels and conventional electricity are highly beneficial. Examples include solar thermal systems, solar electric (photovoltaic) systems, and wind turbines. Other power generation equipment, such as fuel cells and some energy storage systems (like batteries) are included here because they help us accommodate varied energy sources so that we may eventually move beyond fossil-fuel dependence.
The Skystream 3.7, manufactured by Southwest Windpower, is a small wind turbine with a nameplate (rated) capacity of 2.1 kW, an annual power output of 3.4 MWh, and a rated sound level of 41.2 dB(A). It is certified to AWEA Standard 9.1-2009 by the SWCC. The Skystream 3.7 has a diameter of 12 ft and is available installed on poles ranging in height from 34–110 feet. It is designed for grid-tied applications. The average Skystream 3.7 costs between $15,000–$18,000 with installation, and the five-year warranty covers every part. The Skystream contains only two moving parts (the rotor shaft and the yaw assembly) and Southwest recommends maintenance every five years, as opposed to the standard industry of every year.
Most large wind-power systems are installed in centralized wind farms, with the power fed into electric utility grids. Included here are smaller wind turbines that are more appropriate for individual homes or commercial buildings. Like solar power systems, these generators may be designed for use in grid-tied or off-grid applications. Note that most building-integrated wind installations do not perform well, often not achieving even modest expectations. You can read more on that in The Folly of Building-Integrated Wind in EBN.
The small wind industry is plagued by exaggerated power output claims and products that require frequent maintenance. Growing adoption of AWEA Standard 9.1-2009, a standard designed to regularize testing procedures and performance numbers for small wind turbines is strengthening the small wind market and improving the experience for consumers.
GreenSpec lists products that have been earned certification or conditional certification to AWEA Standard 9.1-2009 from the Small Wind Certification Council (SWCC) or Intertek. We recommend avoiding any small wind turbines not certified to AWEA standards (and thus not listed in GreenSpec).
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