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Wind Rotor Swept Area and Geometry Comparison

Calculate circular horizontal-axis or straight vertical-axis rotor area, then compare two geometries on the same wind speed and density basis.

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Inputs that matter
Rotor geometry, Rotor diameter (m), Rotor swept height (m), Sources and assumptions, and 6 more
Output to expect
Rotor swept geometry, Compare rotor swept areas
  • 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

Rotor swept geometry

Calculate the swept area of a horizontal-axis circular rotor or a straight-bladed vertical-axis rectangular rotor. Area alone does not determine Cp, shaft power, electrical output or annual energy.

Circular swept area = πD²/4; straight vertical-axis swept area = D × H.

Compare rotor swept areas

Compare two explicitly chosen rotor geometries. The area ratio also describes the kinetic power ratio only when wind speed and density are identical; it does not establish actual turbine output.

Area ratio = area B / area A at identical resource conditions.

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.

→ 19.634954 m² swept area

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.

→ 1.018592× swept-area ratio B/A

FAQ

Calculate the swept area of a horizontal-axis circular rotor or a straight-bladed vertical-axis rectangular rotor. Area alone does not determine Cp, shaft power, electrical output or annual energy. Compare two explicitly chosen rotor geometries. The area ratio also describes the kinetic power ratio only when wind speed and density are identical; it does not establish actual turbine output.

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 Rotor Swept Area and Geometry Comparison

Calculate the swept area of a horizontal-axis circular rotor or a straight-bladed vertical-axis rectangular rotor. Area alone does not determine Cp, shaft power, electrical output or annual energy. Compare two explicitly chosen rotor geometries. The area ratio also describes the kinetic power ratio only when wind speed and density are identical; it does not establish actual turbine output.