Maker Label Studio

Wind Turbine Power Calculator

Estimate instantaneous turbine output, annual energy, and annual revenue from rotor size, wind speed, Cp, air density, and capacity factor.

Inputs

Use site-average wind speed and a realistic capacity factor for the project stage.

Environmental, EHS & Energy
Choose whether the rotor size is entered as blade radius or full diameter.
Default example: 40 m blade radius.
Power changes with the cube of wind speed.
Default 0.35. Cp must be at or below the 0.59 Betz limit.
Default 1.225 kg/m3 at sea-level standard atmosphere.
Enter percent, for example 35 for a 0.35 capacity factor.
Used only to estimate annual revenue.

Results

The calculation uses P = 0.5 x rho x A x v^3 x Cp and annual kWh = kW x 8760 x capacity factor.

Wind Turbine Power Report

Generated by Maker Label Studio. Formula: P = 0.5 x rho x A x v^3 x Cp.

Instantaneous Power
0.00 kW
0.00 W
Annual Energy
0.00 kWh
0.00 MWh per year
Annual Revenue
$0.00
$0.0000 per kWh
Effective blade radius
0.00 m
Swept area
0.00 m2
Wind speed
0.00 m/s
Power coefficient
0.350
Air density
1.225 kg/m3
Capacity factor
35.0%

Cited category: Environmental, EHS & Energy. This tool applies the standard wind power relationship P = 0.5 x rho x A x v^3 x Cp, with swept area A = pi x r^2 and Cp capped by the 0.59 Betz limit.

Self-tests

Runs golden tests against the pure swept-area, power, and annual-energy functions.

Self-tests: not run

About the Wind Turbine Power Calculator

Wind turbine power estimates the mechanical power available from wind speed, rotor swept area, air density, and power coefficient. Developers, farmers, educators, and energy analysts can test turbine size, annual energy assumptions, and revenue scenarios while remembering that real output depends on the site wind distribution, controls, losses, and rated-power limits.

How it works

  1. Enter rotor diameter or swept area.
  2. Add wind speed, air density, and an appropriate power coefficient.
  3. Set operating hours, capacity assumptions, and electricity value if estimating revenue.
  4. Compare theoretical power with annual energy and practical loss notes.

Frequently asked questions

Why does wind speed have such a large effect on power?

Available wind power is proportional to wind speed cubed. A modest increase in wind speed can greatly increase theoretical power, which is why site wind data is more useful than a single average guess.

What is a realistic power coefficient?

The power coefficient depends on turbine design and operating point and must be below the Betz limit. Use manufacturer performance data when available instead of assuming the maximum theoretical value.

Can average wind speed predict annual kWh accurately?

Not by itself. Annual energy depends on the full wind-speed distribution, cut-in speed, rated speed, cut-out speed, turbine availability, wake losses, and electrical losses.

Why include air density in the calculation?

Denser air contains more mass flow through the rotor and therefore more available power. Temperature, elevation, and pressure all affect air density.

Does calculated power exceed the turbine rating?

It can if the formula is used outside the machine's operating envelope. Real turbines limit output at rated power and shut down above cut-out wind speed.

References