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 A typical spacing between turbines in a wind farm in terms of their rotor diameters D is approximately?
The wind velocity of an airstream is 10 m/s.
a.) If the density of the air is 1 kg/m3, then what is the Wind Energy Density?
b.) If the effective area of the rotor is 15 square meter and if the coefficient of performance (Cp) equals the Betz Limit (16/27 = 0.59), then what is the maximum power that can be extracted from the airstream with this rotor?
The wind speed at 10 meters height is 9 meters/second. What will be the estimated wind speed at 70 meters, using the power rule, with an exponent of 1/7 ?
Determine the number of wind turbines needed to generate 30 Megawatthours of electricity per day if each turbine is 40% efficient, has an effective area of 10 square meter, and is powered by a wind stream with a constant velocity of 12 kph. Assume that the wind blows for only 16 hours per day.

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