Turby is a revolutionary vertical axis wind turbine designed for use in an urban or built-up environments. It is a 2.5 kilowatt wind generator designed for high rooftops and can generate enough electricity to reduce the electric bill of a typical home by two thirds. The Turby has 3 helically shaped composite blades located at a fixed distance from the shaft. It has very low vibrations, very low noise level and an excellent efficiency.
Modern horizontal axis wind turbines (HAWT) usually have a rather high efficiency but their construction is expensive. They have to be directed in the direction of the wind, either manually or by the use of an on-board sensor control mechanism. Vertical-axis turbines do not need such a control system; it is completely irrelevant from which side the wind blows; the position of the rotor is always right. Because of their relative simplicity, their construction cost is much less than a HAWT.
The wind pulls the blades around on both the windward and leeward sides of the turbine which spreads the torque evenly over the entire revolution and the blades have an angle of attack less than 20 degrees. These two features combine to prevent the destructive pulsations and the noise of other turbines. Another advantage of the helical twist is that the blades generate torque well from upward-angled airflow which is frequently found in urban areas.
The only correct placement of the Turby is close to the middle of the roof on a mast with a height of 5 meters or higher. If placed near the prevailing wind roof edge the power will be reduced to about 1/3 of that of a centrally placed turbine because the turbine is most efficient when the wind is perpendicular to the turbine and when the turbine is exposed to winds from all directions.
Height 2890 mm (9.5 ft)
Diameter 1999 mm (6.6 ft)
Weight including blades 136 kg (299 pounds)
Rated power 2.5 kW @ 14 m/s (46 ft/s) wind speed
Peak power 3.0 kW
Output 220-240 V, 50 HZ (60HZ model under development)
Survival wind speed 55 m/s (180 ft/sec)
More detailed specifications can be found in the referenced brochure.
The price of the basic Turby is 11,466 euros (US$13,881) plus the cost of a mast, foundation and installation expenses. A detailed price list is referenced on the company website.
Thanks to the tip by the Extreme Technology blog
Turby: The wind turbine for the built-up environment, Turby B.V. Brochure
Turby B.V. , Lochem, The Netherlands