Professor Prof. Yuji Ohya of the Kyushu University research institute for applied mechanics (RIAM) has been working with a team to improve the efficiency of wind turbines. Combining an inlet shroud, a diffuser, and a brim into a wind lens, power output has been improved by a factor of 2 to 5 times in several experiments. Turbine noise is also decreased.
The Wind Lens works by creating an area of low pressure behind the turbine that essentially sucks the wind through the turbine, increasing effective wind speed. As wind power is proportional to the wind speed cubed, the wind lens changes the fluid dynamics around the turbine to increase its power.
Karl Burkart of Mother Nature Network walks us through the implications. The US is ranked 3rd in the World for potential wind resources. Using just 20% of that potential and turbines with a wind lens modification, sufficient power could be generated to satisfy 100% of present US electrical production.
The RIAM researchers anticipate the best use of wind turbines is offshore, where winds tend to be more constant and speeds higher. In an effort to promote the Wind Lens applications offshore, they have also designed a hexagon floating platform that could be used in conjunction with the wind lens turbine technology.