When most people think of wind power they think of large-scale wind farms with fields of huge three-bladed horizontal axis turbines.
With such farms requiring lots of room they are generally unsuitable for placement in or even near large cities. Smaller turbines tailored for urban environments such as AeroVironment’s Architectural Wind System, the Honeywell Windgate and the Windspire represent a growing sector though, and the latest to catch our eye is the IMPLUX – a vertical axis turbine designed to harness the power of the wind blowing from all directions.
The key to the IMPLUX, which was designed by inventor Varan Sureshan, is the omni-directional shroud that forms the outer covering of the turbine and directs the wind from all directions up through the unit to turn an aerofoil propeller rotor like that used on horizontal axis wind turbines. The shroud, which wouldn’t look out of place in The Jetsons, consists of a series of fixed horizontal blades that are shaped to capture the wind and accelerate it up into the central chamber to turn the turbine rotor.
To stop the wind simply blowing straight through the shroud, the horizontal blades are angled to direct the wind upwards. Sureshan says the wind entering the bottom-most opening, which has the highest focusing ability, forms a “fluid dynamic gate” – essentially an air curtain – that blocks the wind entering on one side from escaping out the other, instead forcing it up a past the rotor.
Sureshan says his invention is capable of generating the same amount or more electricity than a standard horizontal wind turbine with the same sized rotor, but with reduced noise, maintenance and the ability to harness the power of wind that is continuously and rapidly changing direction and speed. This makes it suitable for the swirling wind patterns usually found on the tops of high-rise buildings within cities.