Plant Utilities worked example

Cooling Load Variation at 29% weather and production allowance: a worked example

This scenario runs the cooling load variation calculation on the strong side: 29% weather and production allowance, with every other input held at its documented default. Use it when reviewing cooling load variation for a utility budget, maintenance priority, capacity check, energy project, or production support plan.

The inputs for this scenario

  • Extra cooling load to remove: 240 cooling-min (unchanged)
  • Chiller recovery rate: 1 cooling-min / min (unchanged)
  • Weather and production allowance: 29 % (raised for this scenario; the documented default is 25)

Working through the calculation

  • Applying the documented formula (Base cooling load variation time = extra cooling load minutes รท recovery rate) to the inputs above produces each figure below.
  • At this operating point the engine returns 310 min for required cooling load variation time, the number this scenario is built around.
  • At this operating point the engine returns 240 min for base cooling load variation time.
  • At this operating point the engine returns 29 % for allowance applied.
  • At this operating point the engine returns 1 cooling-min / min for utility coverage rate.

How this compares with the baseline

  • Against the tool's baseline example, where weather and production allowance sits at 25% and the headline result is 300 min, this scenario comes in 3.2% above the baseline at 310 min.
  • Use it when sizing recovery windows for a cooling demand surge, checking whether a chiller can absorb a new load before setpoints drift, or scheduling load-shed timing on hot days. Treat this as a target state: the delta against the baseline quantifies what the improvement is worth before you commit to chasing it.

Results at a glance

  • Required cooling load variation time: 310 min (headline result)
  • Base cooling load variation time: 240 min
  • Allowance applied: 29 %
  • Utility coverage rate: 1 cooling-min / min

Run it with your numbers

  • Every input above is editable in the live Cooling Load Variation calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.