EV Charging Infrastructure Manufacturing worked example

Thermal Derating with derated charger or test load of 75 kW: a worked example in ev charging infrastructure manufacturing

Here is what the math looks like when conditions slip. We hold every other input steady and drop derated charger or test load to 75 kW, then walk the calculation through step by step. Estimate usable charger output after thermal derating from rated output, derating runtime, energy rate, and units produced or tested.

The inputs for this scenario

  • Derated charger or test load: 75 kW (the input this scenario stresses; the baseline uses 150)
  • Thermal derating runtime: 6 hr (held at the documented default)
  • Blended electricity rate: 0.14 $ / kWh (held at the documented default)
  • Chargers or modules processed: 4 units (held at the documented default)

Working through the calculation

  • The calculation starts from the formula this tool documents: Thermal derating energy cost = derated load × runtime × blended electricity rate.
  • Thermal derating energy cost works out to 63 $ at these inputs, and this is the headline figure for the scenario.
  • Thermal derating energy used works out to 450 kWh at these inputs.
  • Energy cost per charger/module works out to 15.75 $ / unit at these inputs.
  • Hourly thermal derating energy cost works out to 10.5 $ / hr at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where derated charger or test load sits at 150 kW and the headline result is 126 $, this scenario comes in 50% below the baseline at 63 $.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to derated charger or test load, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. It models steady-state energy draw only — it ignores the dynamic ramp during a real derating event, cooling-fan and chiller parasitic loads, and any regenerative recovery if the test bench feeds power back to the grid.

Results at a glance

  • Thermal derating energy cost: 63 $ (headline result)
  • Thermal derating energy used: 450 kWh
  • Energy cost per charger/module: 15.75 $ / unit
  • Hourly thermal derating energy cost: 10.5 $ / hr

Run it with your numbers

  • To rerun this with your own numbers, open the live Thermal Derating calculator, set derated charger or test load to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.