Wind Energy Calculator
Estimate annual energy production from a wind turbine based on rotor diameter, wind speed, and capacity factor.
meters
m/s
kg/m3
%
Annual Energy Production
1,295 MWh
Theoretical Power422 kW
Homes Powered123 homes
CO2 Avoided540 metric tons
Annual Energy Production vs Rotor Diameter
How to Calculate Wind Energy Production
Wind turbine energy output depends on wind speed, rotor size, and efficiency.
Formula
Power (W) = 0.5 * Air Density * Swept Area * Wind Speed^3 * Efficiency
Swept Area = pi * (Diameter/2)^2
Annual Energy = Power * 8,760 hours * Capacity Factor
The Betz limit caps theoretical efficiency at 59.3%. Modern turbines achieve about 40% (Cp = 0.4). Capacity factor accounts for variable wind conditions.
Example Calculation
An 80m rotor wind turbine in 7 m/s average wind with 35% capacity factor.
- 01Swept area: pi * (80/2)^2 = 5,027 m2
- 02Theoretical power: 0.5 * 1.225 * 5,027 * 7^3 * 0.4 = 423,096 W = 423 kW
- 03Annual energy: 423 * 8,760 * 0.35 = 1,296 MWh
- 04Homes powered: 1,296 / 10.5 = 123 homes