What this calculator does
Wind turbine power output works out electrical power generated by a wind turbine from rotor size, wind speed and efficiency. Enter your own figures above and the answer updates as you type: nothing is fixed in the code, so the result reflects exactly the numbers you supply.
The formula this calculator evaluates is printed under the tool and explained below, so you can check the working by hand or reuse it in a spreadsheet.
The formula
FormulaPwind = ½ρAv³, A = π(D/2)²; Poutput = Cp·Pwind, Cp bounded by the Betz limit (59.3%)
The inputs explained
| Field | What to enter |
|---|---|
| Rotor diameter (m) | A number, measured in m. Starts at 80. |
| Wind speed (m/s) | A number, measured in m/s. Starts at 8. |
| Air density (kg/m³) | A number, measured in kg/m³. Starts at 1.225. |
| Turbine efficiency coefficient Cp | A number. Starts at 0.35. |
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How the answer changes with rotor diameter
Every other input is held at the calculator’s starting values while rotor diameter varies. Select any row to load that scenario into the calculator.