The Karman vortex generated by the "brim" of the diffuser with a brim creates a low-pressure area behind the diffuser, and this low-pressure area attracts wind. The accelerated wind increases 1.5 times at the blade tips and turns the wind turbine. Since wind energy is proportional to the cube of the wind speed, a wind turbine with the same rotor diameter can generate about 2 to 3 times as much power. The "lens wind turbine," which was optimized through a series of joint research efforts, is patented by Kyushu University, and we have obtained an exclusive license.

The blade tip vortices generated at the blade tips and the opposite-direction vortices induced by the diffuser's inner wall cancel each other out as they move downstream, suppressing the blade tip vortices that are the source of aerodynamic noise and significantly reducing the noise level. Noise measurements of a 3kW turbine showed a sound pressure level of less than 55dB near the wind turbine at wind speeds of 5 to 14m/s. The noise level is not noticeable even in residential areas. Noise is not a concern even in the vicinity of residential areas.

Diffusers (rings) are clearly visible to birds. "Bird strike", a collision between a bird and a blade, which is considered one of the major problems of wind power generation, has been confirmed to be less likely to occur. We have never experienced one until now.

It is expected that the wind turbine weight, introduction cost, and power generation cost will decrease in proportion to 1/√n. The wind collection effect of the lens and the fluid interference effect of the multi are combined, and the power generation amount is further increased by 10 to 20%. It has high potential as a wind turbine system, and we are conducting research toward its use as a 7-wheel multi-lens wind turbine and an offshore wind power system.

Actual annual power generation depends on installation conditions (surrounding topography, weather conditions, etc.). Based on our wind turbine power generation output curve and the annual average wind speed, we assumed the appearance of general wind (Weibull distribution or Rayleigh distribution), and calculated the power generation amount when connected to the grid in the table below. Considering the operation rate of the wind turbine system and the self-consumption of the controller, etc., the estimated power generation amount is shown as a reference annual power generation amount. (Note: The capacity factor is based on our field test data. The two-year demonstration test from April 2016 to January 2018 in Hibikinada, Kitakyushu City)