Microgrid & Distributed Energy Equipment worked example

Factory Acceptance Test Energy with connected test load of 30 kW: a worked example

What does the result look like when connected test load reaches 30 kW? The full calculation is worked below with real intermediate numbers. Use it when factory acceptance testing on microgrid and distributed energy equipment needs a defensible energy number for the budget or quote.

The inputs for this scenario

  • Connected test load: 30 kW (raised for this scenario; the documented default is 12)
  • FAT runtime: 8 hr (unchanged)
  • Blended electricity rate: 0.12 $ / kWh (unchanged)
  • Units tested: 1,000 units (unchanged)

Working through the calculation

  • Applying the documented formula (Total FAT energy cost = connected test load × FAT runtime × blended electricity rate) to the inputs above produces each figure below.
  • At this operating point the engine returns 240 kWh for fat energy used, the number this scenario is built around.
  • At this operating point the engine returns 28.8 $ for total fat energy cost.
  • At this operating point the engine returns 0.03 $ / piece for energy cost per unit tested.
  • At this operating point the engine returns 3.6 $ / hr for hourly fat energy cost.

How this compares with the baseline

  • Against the tool's baseline example, where connected test load sits at 12 kW and the headline result is 96 kWh, this scenario comes in 150% above the baseline at 240 kWh.
  • A figure at this level is achievable when connected test load is genuinely sustained, not just peaked for a shift. It assumes the connected load is roughly constant for the full runtime; pulsed, ramped, or step-load FAT profiles will draw less than load × time, so derate with a duty factor for accuracy.

Results at a glance

  • FAT energy used: 240 kWh (headline result)
  • Total FAT energy cost: 28.8 $
  • Energy cost per unit tested: 0.03 $ / piece
  • Hourly FAT energy cost: 3.6 $ / hr

Run it with your numbers

  • Every input above is editable in the live Factory Acceptance Test Energy calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.