Waste-to-Energy Equipment worked example

Boiler Heat Recovery at 83% economizer recovery efficiency: a worked example

This scenario runs the boiler heat recovery calculation on the strong side: 83% economizer recovery efficiency, with every other input held at its documented default. Use it when justifying an economizer or heat-recovery boiler upgrade to weigh recovered energy value against the annualized capital it carries.

The inputs for this scenario

  • Recovered steam output: 22,000 MWh (unchanged)
  • Steam heat value: 45 $/MWh (unchanged)
  • Economizer recovery efficiency: 83 % (raised for this scenario; the documented default is 72)
  • Economizer capital charge: 180,000 $ (unchanged)

Working through the calculation

  • Applying the documented formula (Total = recovered MWh x heat value x (recovery efficiency รท 100) + capital charge) to the inputs above produces each figure below.
  • At this operating point the engine returns 1,001,700 $ for total boiler heat recovery cost, the number this scenario is built around.
  • At this operating point the engine returns 45.53 $ / piece for boiler heat recovery cost per unit.
  • At this operating point the engine returns 821,700 $ for variable boiler heat recovery cost.
  • At this operating point the engine returns 180,000 $ for fixed boiler heat recovery adder.

How this compares with the baseline

  • Against the tool's baseline example, where economizer recovery efficiency sits at 72% and the headline result is 892,800 $, this scenario comes in 12.2% above the baseline at 1,001,700 $.
  • Use it when appraising an economizer or flue-gas heat-recovery retrofit, or when setting an internal transfer price for the steam the boiler exports. 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

  • Total boiler heat recovery cost: 1,001,700 $ (headline result)
  • Boiler heat recovery cost per unit: 45.53 $ / piece
  • Variable boiler heat recovery cost: 821,700 $
  • Fixed boiler heat recovery adder: 180,000 $

Run it with your numbers

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

Last reviewed 2026-05-12.