Home > > Wind generators news > > Small wind turbines
Small wind turbines may be as small as a four hundred watt generators for residential use. The small ones often have direct drive generators, direct current output, aeroelastic blades, lifetime bearings and use a vane to point into the wind. Larger, more costly turbines generally have geared power trains, alternating current output, flaps and are actively pointed into the wind. Direct drive generators and aeroelastic blades for large wind turbines are being researched.
A small wind turbine can be installed on a roof. Installation issues then include the strength of the roof, vibration, and the turbulence caused by the roof ledge.
Small-scale wind power in rural Indiana.
Small-scale wind power in rural Indiana.
Small scale turbines for residential-scale use are available that are approximately 7 feet (2 m) to 25 feet (8 m) in diameter and produce electricity at a rate of 900 watts to 10,000 watts at their tested wind speed. Some units are designed to be very lightweight, e.g. 16 kilograms (35 lb), allowing rapid response to wind gusts typical of urban settings and easy mounting much like a television antenna. It is claimed that they are inaudible even a few feet under the turbine.[citation needed] Dynamic braking regulates the speed by dumping excess energy, so that the turbine continues to produce electricity even in high winds. The dynamic braking resistor may be installed inside the building to provide heat (during high winds when more heat is lost by the building, while more heat is also produced by the braking resistor). The location makes low voltage (around 12 volt) distribution practical.
Residential wind turbines typically cost between $12,000 and $55,000, but there are incentives and rebates available in 19 states in the U.S. that can cut the purchase price by up to 50 percent.
The American Wind Energy Association has released several studies on the small wind turbine market in the U.S. and abroad, showing that the U.S. continues to dominate the Small Wind industry. According to another organization, the World Wind Energy Association, it is difficult to assess the total number or capacity of small-scaled wind turbines, but in China alone, there are roughly 300,000 small-scale wind turbines generating electricity.
The dominant models on the market, especially in the United States, are horizontal-axis wind turbines (HAWT).
There have been a number of recent developments of mini-turbines which could be adapted to home use, including:
* The AeroTecture vertical-axis turbine
* The AeroVironment Architectural Wind Project
* The piezoelectric windmill project
* The Swift home wind turbine.The Swift project peaked in 2004 and has had some implementation difficulties while promising to be a low-noise/safe roof-mount/low-cost alternative
* The Motorwave micro-wind turbine
Consumer guides are available to help potential customers learn about residential-scale wind systems, three of which are:
* "Small Wind Electric Systems: A U.S. Consumer¡¯s Guide" by the Dept. of Energy¡¯s Wind Powering America program [4]
* "Wind Turbine Buyer¡¯s Guide" From Home Power Magazine
* "Apples & Oranges 2002: Choosing a Home-Sized Wind Generator"
Much more information is also available at the American Wind Energy Association¡¯s web site at:
* www.awea.org/smallwind
* FAQ: http://www.awea.org/smallwind/faq.html
* www.awea.org/smallwind/toolbox2/index.html
Related Questions:
1. Forest fires a real concern for areas hit hard by hurricanes
2. China Places Order for Hundreds of Vestas Wind Turbines
