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Electrical Usage Tool Guide

What this tool does – [Tool]

This tool allows you to easily calculate the annual electrical cost of operating a ventilation fan or any other electrical appliance that is set up for continuous or intermittent use. If the fan is set up for intermittent use, you will need to know the operating schedule in order to calculate the annual motor operating cost.

Calculated values

  • Annual electrical cost.
  • Annual electrical usage.
  • Annual usage time.


  • Clicking the label for any input or result will cause a popup help box to appear. This help box includes the allowed and normal values (for inputs).
  • Keep in mind the CFM/W (m3/min/W) when you are selecting a fan; the higher this value, the better. This is called the efficacy level.
  • If the homeowner turns the fan off when the dwelling windows are open, do your best to estimate this fan-off time and include it in your input values for the Ventilation Electrical Usage tool.


When installing a ventilation fan, especially one that will operate most of the time, it is important to consider the cost of running the motor. If the fan you are using meets EnergyStar standards, the energy used and the cost of operating the fan will be as low as possible.