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Wind Kinetic Power and Ideal Betz Bound

Calculate available wind-stream power and the ideal actuator-disc Betz shaft-power bound from rotor diameter, air density and actual wind speed.

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Inputs that matter
Circular rotor diameter (m), Wind speed (m/s), Air density (kg/m³), Sources and assumptions
Output to expect
Ideal actuator-disc power bound
  • Check the units and required inputs before comparing results.
  • Keep the assumptions with a copied result so you can reproduce the calculation later.
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Reference & details

How it works

Ideal actuator-disc power bound

Calculate kinetic stream power and the ideal Betz shaft-power bound for a circular unshrouded rotor at the stated air density and wind speed. Zero wind gives zero power.

Stream W = 0.5ρ(πD²/4)v³; ideal extracted shaft W ≤ stream W ×16/27.

Updated: September 2026

Example Scenarios

Try this example to see the calculation, then enter actual documented values and preserve the measurement conditions. A failed or unresolved comparison is part of the record.

→ 20.781635 kW ideal shaft bound

FAQ

Calculate kinetic stream power and the ideal Betz shaft-power bound for a circular unshrouded rotor at the stated air density and wind speed. Zero wind gives zero power.

Use the exact equipment data, measurement point, operating conditions and units described in the selected mode. Record source documents, dates and unresolved conditions in Sources and assumptions. Built-in examples illustrate arithmetic; they are not manufacturer ratings or approved designs.

Use Save planning case for an explicit local history entry. Copy MD keeps current inputs and notes; Download CSV exports the result breakdown. Export portable copies before clearing storage and save a separate case after changing equipment, conditions or measurements.

About Wind Kinetic Power and Ideal Betz Bound

Calculate kinetic stream power and the ideal Betz shaft-power bound for a circular unshrouded rotor at the stated air density and wind speed. Zero wind gives zero power.