Can even be installed on small buildings - Lightweight, compact ring-turbine
In 2011, Peace Frontier built a prototype wind-powered generator using a ring turbine. This contains a rotating outer-rotor generator, with a coil on the inside and magnets on the outside. Propeller and gyro mill generators have been widely used to date. But the propeller generator has a large surface which receives the force of the wind, which raises concerns about material strength. The gyro mill generator, on the other hand, has the problem of low-frequency noise when the rotation speed is low. But with ring turbines, various issues have been eliminated, making it possible to generate electricity even in gentle winds.
"In a ring turbine, the path of the wind currents are made narrow, thereby increasing the wind speed and causing eddies. This increases the force in the direction of rotation, so the generation efficiency is higher. One advantage of this type of wind turbine is that it can generate sufficient electricity with a wind speed of only 3-5 m/s in urban areas. Another advantage is that it doesn't make a noise. And I personally like the fact that, because the vanes don't stick out, the turbine doesn't injure birds or people. I think these three things are big advantages."
A lightweight, compact ring-turbine generator can be easily taken to the roof of a small building on a lift. Also, a prototype with a die-cast rotor can deliver 878 W, as actually measured output. That's nearly four times the output of a propeller or gyro mill generator.
"The first thing we considered was that erecting poles is difficult and costly. One advantage of this system is that it can be easily installed on roofs, like a cellphone antenna. Another advantage of this design is that it doesn't cause problems of large turbines, such as low-frequency noise. Compared with solar energy, wind turbines have the advantage of generating power even at night. We think this will be greatly beneficial if the system is used as an emergency power supply."
Looking ahead, Peace Frontier is thinking about installing ring turbines as emergency power supplies in schools and other buildings that become community shelters in emergencies, and overseas, on cellphone antenna towers in deserts or jungles.
Source by: Peace Frontier