Plant Utilities worked example

Steam Demand at 63% boiler delivery efficiency: a worked example

Here is what the math looks like when conditions slip. We hold every other input steady and drop boiler delivery efficiency to 63%, then walk the calculation through step by step. Estimate effective steam demand in pounds per hour from process steam use, runtime, and boiler delivery efficiency.

The inputs for this scenario

  • Steam used by process: 48,000 lb (held at the documented default)
  • Operating time: 8 hr (held at the documented default)
  • Boiler delivery efficiency: 63 % (the input this scenario stresses; the baseline uses 88)

Working through the calculation

  • The calculation starts from the formula this tool documents: Raw steam demand = steam used by process ÷ operating time.
  • Effective steam demand works out to 3,780 lb / hr at these inputs, and this is the headline figure for the scenario.
  • Raw steam demand works out to 6,000 lb / hr at these inputs.
  • Efficiency works out to 63 % at these inputs.
  • Operating time works out to 8 hr at these inputs.

How this compares with the baseline

  • Against the tool's baseline example, where boiler delivery efficiency sits at 88% and the headline result is 5,280 lb / hr, this scenario comes in 28.41% below the baseline at 3,780 lb / hr.
  • The practical read: the gap between this scenario and the baseline is entirely attributable to boiler delivery efficiency, so recovering it is worth quantifying in dollars before considering equipment or staffing changes. A single average over the shift hides peaks — batch loads, startup, and simultaneous demands can spike well above the average, so size headers and boilers to the peak, not this mean.

Results at a glance

  • Effective steam demand: 3,780 lb / hr (headline result)
  • Raw steam demand: 6,000 lb / hr
  • Efficiency: 63 %
  • Operating time: 8 hr

Run it with your numbers

  • To rerun this with your own numbers, open the live Steam Demand calculator, set boiler delivery efficiency to your actual value, and adjust the remaining inputs to match your operation.

Last reviewed 2026-05-12.