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Engineering calculator · Updated 17 September 2026

Cooling Tower Fan Specific Power Calculator — kW per Flow & Heat Rejection

Benchmark cooling-tower fan demand against circulating-water flow and rejected heat. Returns kW per 1,000 gpm, W per m³/h, fan kW per rejected MW and annual energy.

Inputs

Live results

  • Fan specific power 15 kW/1,000 gpm
  • Flow-normalized power 66.043015 W/(m³/h)
  • Heat-normalized power 4.2857143 kW/MW rejected
  • Annual fan energy 60 MWh

Formula

SP=P/Q; thermal-normalized SP=P/Qheat.

Worked example

A 15 kW fan serving 1,000 gpm uses 15 kW/1,000 gpm.

Assumptions and limits

  • Use simultaneous fan input power and operating flow.
  • Variable-speed towers should be compared at similar load and wet-bulb conditions.

FAQs

What does this Cooling Tower Fan Specific Power Calculator calculate?

Benchmark cooling-tower fan demand against circulating-water flow and rejected heat. Returns kW per 1,000 gpm, W per m³/h, fan kW per rejected MW and annual energy.

Is this suitable for final equipment selection?

Use the result for engineering screening and operating diagnostics. Confirm final selections against measured data, OEM curves and applicable codes.

Why are the assumptions explicit?

Plant results depend on reference conditions, pressure basis, efficiencies and measurement locations. Showing assumptions keeps the calculation auditable.

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