Industrial Heat Pumps & Electrified Thermal Systems worked example

Defrost Energy Cost at 72% defrost operating scope: a worked example

This worked example runs the defrost energy cost numbers for a tougher week than the baseline: 72% defrost operating scope instead of the typical 100%. Estimate seasonal defrost operating cost for an air-source industrial heat pump from defrost kWh, electric tariff, scope share, and fixed service cost.

The inputs for this scenario

  • Defrost electricity use: 18,000 kWh (held at the documented default)
  • Electricity cost: 0.11 $ / kWh (held at the documented default)
  • Defrost operating scope: 72 % (the input this scenario stresses; the baseline uses 100)
  • Fixed defrost service cost: 1,200 $ (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Variable defrost energy cost = defrost electricity use × electricity cost × defrost operating scope.
  • Total defrost energy cost works out to 2,626 $ at these inputs, and this is the headline figure for the scenario.
  • Electricity cost works out to 0.15 $ / kWh at these inputs.
  • Variable defrost energy cost works out to 1,426 $ at these inputs.
  • Fixed defrost service cost works out to 1,200 $ at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where defrost operating scope sits at 100% and the headline result is 3,180 $, this scenario comes in 17.43% below the baseline at 2,626 $.
  • Use it when evaluating demand-defrost controls, sizing the parasitic load in a seasonal efficiency model, or budgeting the running cost of an air-source industrial heat pump. A result at this level usually justifies acting on the stressed input before touching anything else, because every other figure in the table is downstream of it.

Results at a glance

  • Total defrost energy cost: 2,626 $ (headline result)
  • Electricity cost: 0.15 $ / kWh
  • Variable defrost energy cost: 1,426 $
  • Fixed defrost service cost: 1,200 $

Run it with your numbers

  • To rerun this with your own numbers, open the live Defrost Energy Cost calculator, set defrost operating scope to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.