Rendering of mid-size 100 kW wind lens turbines/Kyushu University, RIAM

Wind Lens:

A group led by Professor Yuji Ohya at Japan’s Kyushu University has created an innovative new turbine that builds upon the existing three-blade horizontal axis design but adds a wind concentration system to accelerate power generation. By surrounding the blades with a cylinder, engineers have created a vortex that increases the speed at which they turn. Though it seems intuitive that a lens would obstruct the flow of air, Ohya and his collaborators did so in an effort to lower the pressure and create the vortices that allow for faster rotation. According to claims, this technique can produce power at two to five times the standard rate.

Tests have been encouraging so far. An experimental installation was shown to produce 104 kW of power with wind speeds of 12 miles per second, confirming the findings of earlier wind tunnel tests. It has yet to be seen how larger turbines might hold up, given the added wind load that the lens would require them to carry. The next step, as of Fall 2011, was for the research team at Kyushu University to begin construction of an offshore wind farm in Japan’s Hakata Bay that incorporates two 5 kW wind lens turbines attached to a float measuring 60 feet across. Beyond that is a more elaborate plan to install 50-foot-tall 100 kW turbines on larger honeycomb-shaped floats in the Genkai Sea, north of Fukuoka. If these initial applications prove successful, it’s likely that things will speed up for the wind lens from there forward.

Airborne Wind Turbines:

Ever since the Ancient Greek engineer Heron of Alexandria harnessed the wind to operate an organ, and possibly earlier, wind has been