Mechanical to Electrical Power Calculator

Mechanical to Electrical Power Calculator

Convert same-shaft torque and rpm to mechanical power, then apply stated shaft-to-electrical efficiency. This is an operating-point conversion, not a fuel or nameplate-rating estimate.
Electrical Power:
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What this calculator measures

Convert same-shaft torque and rpm to mechanical power, then apply stated shaft-to-electrical efficiency. This is an operating-point conversion, not a fuel or nameplate-rating estimate.

Inputs and units

Use readings and ratings that describe the same equipment, operating interval, and measurement boundary. The sample entries are editable examples; they do not establish the specifications of your generator.

Input Example entry or choice
Measured shaft torque (N·m) 100 — enter a documented value
Rotational Speed (RPM) 1500 — enter a documented value
Shaft-to-electrical conversion efficiency (%) 90 — enter a documented value

Calculation method

Mechanical kW = torque N·m × rpm × 2π ÷ 60,000. Multiply that power by shaft-to-electrical efficiency as a fraction to estimate electrical kW at the stated boundary. Torque and rpm must describe the same shaft and operating point.

Worked example

100 N·m at 1,500 rpm is about 15.708 mechanical kW. At a stated 90% shaft-to-electrical efficiency, the electrical estimate is 14.14 kW. The efficiency factor is not an additional power-factor conversion.

Limitations and checks

A calculated operating-point output does not override generator electrical or mechanical ratings. If torque is measured upstream of a gearbox or belt, account for that boundary and the relevant losses separately. The model does not establish fuel efficiency or transient response.

For a practical decision, keep the original readings, the generator model, the relevant manual or specification, and the assumptions alongside the result. A different load, site condition, rating basis, or unit convention can answer a different question even when the arithmetic is correct.

Sources and methodology

Publisher: CSP Digital Media Ltd. To report a formula, unit, or example error, contact us with the tool name, inputs, displayed result, and expected calculation.

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