Video on Small Wind
Will the wind turbine here generate electricity? Yes. Will it do so cost-effectively? Not in a million years.
• Vertical axis machines are intrinsically left efficient than their horizontal axis counterparts.
• This device invokes drag rather than lift mechanics.
• Small wind is never a good deal, because power is a function of swept area, which itself is a function of the square of the radius, meaning that bigger is always better.
• It’s at ground level, where wind conditions are poor.
The turbine in the video looks like it could be 1 meter wide and 3 meters high, which is the equivalent to a rotating blade whose radius is 0.95 meters. Plugging this to our wind power formula:
P = π/2 * r² * v³ * ρ * η, one watt is calculated as 1 W = 1 kg * m² / s³
and assuming a a constant “moderate breeze” (15 mph), we get 205 Watts. You’d need four of them to power your refrigerator.