The new AeroVironment turbine design is shown here with the optional canopy.
Calling for a change from “turbine on a stick” wind generation equipment, which is unsuitable for most urban environments, AeroVironment, Inc., is introducing a new approach to small-scale wind generation that might best be described as turbines on the parapet. Founded by Paul MacCready, Ph.D., AeroVironment, based in Monrovia, California, has a rich history of applying appropriate technology to the field of aeronautics—MacCready and his company have been pioneers in human-powered and solar-powered flight since the 1970s. AeroVironment also has a long track record with utility-scale wind farms, so it had a lot of experience to draw from when it set out to tackle the problem of wind power in urban settings.
The new AVX400 turbine, which will be released publicly in the fall of 2006, embodies a number of breakthroughs that greatly improve the viability of wind on some urban and suburban buildings. Among the technical improvements, the blades of the turbines were designed to operate at relatively low speeds, which dramatically reduces noise and vibration from the turbines—a major deterrent to placing turbines on buildings. More significant, however, is AeroVironment’s discovery that on wide buildings, even if they are not especially tall, the wind intensifies as it crests the building’s façade and moves over the roof. “If you go to the edge and look over, you get this rush of wind,” notes Paul Glenney, AeroVironment’s director of energy initiatives. In the field, AeroVironment has measured a 40% boost in wind speed, which translates into about 2.7 times as much energy in the wind.