Plant Utilities worked example

Boiler Blowdown Loss at 110% unrecovered heat share: a worked example

What does the result look like when unrecovered heat share reaches 110%? The full calculation is worked below with real intermediate numbers. Use it when reviewing boiler blowdown loss for a utility budget, maintenance priority, capacity check, energy project, or production support plan.

The inputs for this scenario

  • Boiler blowdown volume: 420 klb (unchanged)
  • Fuel and water value per klb: 5.6 $ / klb (unchanged)
  • Unrecovered heat share: 110 % (raised for this scenario; the documented default is 100)
  • Testing and treatment adder: 150 $ (unchanged)

Working through the calculation

  • Applying the documented formula (Total boiler blowdown loss cost = boiler blowdown volume × fuel and water value lost × unrecovered heat share + testing and treatment adder) to the inputs above produces each figure below.
  • At this operating point the engine returns 2,737 $ for total boiler blowdown loss cost, the number this scenario is built around.
  • At this operating point the engine returns 6.52 $ / item for cost per item or period.
  • At this operating point the engine returns 2,587 $ for variable boiler blowdown loss cost.
  • At this operating point the engine returns 150 $ for fixed utility adder.

How this compares with the baseline

  • Against the tool's baseline example, where unrecovered heat share sits at 100% and the headline result is 2,502 $, this scenario comes in 9.4% above the baseline at 2,737 $.
  • A figure at this level is achievable when unrecovered heat share is genuinely sustained, not just peaked for a shift. It uses a single blended value per klb; actual fuel and makeup-water costs vary with load and season, so recompute when energy prices or cycles of concentration change.

Results at a glance

  • Total boiler blowdown loss cost: 2,737 $ (headline result)
  • Cost per item or period: 6.52 $ / item
  • Variable boiler blowdown loss cost: 2,587 $
  • Fixed utility adder: 150 $

Run it with your numbers

  • Every input above is editable in the live Boiler Blowdown Loss calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.