Why hasn't some organisation offered payment for a contest to make the most effecient vertical wind turbine?

Question

If vertical wind turbines could be made thin enough and effecient enough, they could be placed on house rooftops and be very discrete (maybe only about 12 inch tall and 12 feet diameter). A top plate could conceal the spinnig blades. The contest could require that the turbines have a max area, max height, and must work for a certain amount of time (months?). On the start date, entrants would build their turbines on a specific site. The organisation(s) sponsoring the contest would get the rights to the generated electricity. The group with the most effecient turbine after the time frame would win the prize money. Entrants would also pay to enter. I think this would be a great opportunity for many engineering universities and for the organisation(s) sponsoring it. It could also lead to MANY new "rooftop" turbine concepts that could help power individual homes, without having the large "windmill tower". Maybe a similar concept could be used for the most effecient solar panel?

I am talking about a "Savonius Wind Turbine" type.... Google for pictures. It has a vertical axis and the wind turns the blades from the side. But apparently, there is not a "perfect" design for the blades, hence the contest.

Answer 1

Vertical axis wind turbines have a natural appeal because of the design simplicity and because you don't have to point them into wind. The problem is that they are not as efficient as the wind axis turbines. The Savonius rotor windmill is very inefficient extracting only about 15% of the wind's energy (similar to the multi-blade American farm windmill. A windmill only 12 inches tall and 12 feet across and only a few feet above your rooftop would not produce any significant amount of energy. Part of the reason wind turbines are up so high is because that's where most of the wind energy is. I spent several years dreaming about a vertical axis wind turbine design usually called a Giromill or cycloturbine or cyclogyro. I had a huge Excel spreadsheet calculating the lift and drag on each blade at each position around the circle, all based upon the (faulty) assumption that the wind speed and direction were essentially not affected by my turbine. WRONG. When you extract power from the wind, it slows down and the wind behind it starts to "pile up" and go around the windmill instead of through it. Ever wonder why the big wind axis turbines have so few blades. This is why. Adding more blades would decrease the power because it would slow the wind down too much and most of the wind would just go around and avoid the windmill entirely. The term is solidity and both the Savonius Rotor and American farm windmill have way to much of it. The only vertical axis windmill that came close to competing with the wind axis turbines is the Darrieus rotor, which looks sort of like an egg beater. I've given up on windmills, but I'm still working on a home solar energy system.

Answer 2

Presumably because they are happy with the current designs

"maybe only about 12 inch tall and 12 feet diameter"

Since when does wind fall vertically from the skies like rain does?

and even if it did, this next bit kills that

"A top plate could conceal the spinnig blades"

12 ft spinning blades ...... too much energy to put on houses
LETHAL