LOW-TECH MAGAZINE

Reinventing the Small Wind Turbine

Many commercially available small wind turbines with plastic blades and steel towers are infamous for their low reliability, high embodied energy, and limited power output.

Building them out of wood can address these issues. Because of their aesthetic appeal, and thanks to the ability to produce them locally, small wooden wind turbines can also improve the public acceptance of wind power.

Furthermore, innovation in tower design facilitates the installation of small wind turbines, reducing the need for concrete foundations and heavy machinery. 

Image: A wind turbine with wooden blades. Source: EAZ Wind.

Small windmills put to the test

A real-world test performed by the Dutch province of Zeeland (a very windy place) confirms our earlier analysis that small windmills are a fundamentally flawed technology (test results here, pdf in Dutch). Twelve of these much hyped machines were placed in a row on an open plain (picture above). Their energy yield was measured over a period of one year (April 1, 2008 - March 31, 2009), the average wind velocity during these 12 months was 3.8 meters per second (note: update on the wind speed ). Three windmills broke. Find the disappointing results of the others below.

Urban windmills harm the environment

A small windmill on your roof or in the garden is an attractive idea. Unfortunately, commercially available micro wind turbines deliver hardly enough energy to power a light bulb.

Their financial payback time is much longer than their life expectancy and in urban areas they will not even deliver as much energy as was needed to produce them. Sad, but true.

***

Build your own windmill

Traditional micro-wind turbines are plagued by problems. The "Windbelt", which you can easily build yourself, does not have them.