Wind Turbine Power Calculator
Power output from wind speed and rotor size.
Enter your values
Enter the rotor diameter in m.
Enter the wind speed in m/s.
Enter the power coefficient you are working with.
Enter the air density in kg/m³.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Power output
- 12.41 kW
- Swept area
- 113.1 m²
- Annual energy at 30% CF
- 32,623 kWh
- Wind power density
- 314 W/m²
Quick answer
Wind power scales with the cube of wind speed and the square of rotor diameter.
P = ½ρAv³ × Cp
At a glance
| What it does | Power output from wind speed and rotor size. |
|---|---|
| Category | Science |
| Inputs needed | Rotor diameter, Wind speed, Power coefficient, Air density |
| Main output | Power output |
| Formula | P = ½ρAv³ × Cp |
| Cost | Free — no sign-up, no download |
How to use the Wind Turbine Power Calculator
- 1Enter rotor diameter and average wind speed.
- 2Set the power coefficient (Betz limit is 0.59).
- 3Adjust air density for altitude.
Inputs explained
- Rotor diameter(m)
- Enter the rotor diameter in m.
- Wind speed(m/s)
- Enter the wind speed in m/s.
- Power coefficient
- Enter the power coefficient you are working with.
- Air density(kg/m³)
- Enter the air density in kg/m³.
Worked example
Using the values the calculator loads with:
Inputs
- Rotor diameter12 m
- Wind speed8 m/s
- Power coefficient0.35
- Air density1.225 kg/m³
Results
- Power output12.41 kW
- Swept area113.1 m²
- Annual energy at 30% CF32,623 kWh
- Wind power density314 W/m²
Frequently asked questions
Why does wind speed matter so much?
Power scales with the cube — doubling wind speed gives eight times the power.
What capacity factor is realistic?
25–35% onshore, higher offshore.
What do I need to enter into the Wind Turbine Power Calculator?
Just 4 values: rotor diameter, wind speed, power coefficient, air density. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Wind Turbine Power Calculator work out the answer?
Wind power scales with the cube of wind speed and the square of rotor diameter. It applies the formula P = ½ρAv³ × Cp and shows the working so you can check each step by hand.
Is the Wind Turbine Power Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.