Waste-to-Energy Equipment worked example

Feedstock Moisture Impact at 63% excess moisture fraction: a worked example

This scenario runs the feedstock moisture impact calculation on the strong side: 63% excess moisture fraction, with every other input held at its documented default. Use it when evaluating a feedstock contract or pre-drying upgrade to quantify the generation and fuel hit that high-moisture refuse imposes.

The inputs for this scenario

  • Wet Feedstock Throughput: 60,000 tonnes (unchanged)
  • Drying Penalty per Tonne: 6.5 $/tonne (unchanged)
  • Excess Moisture Fraction: 63 % (raised for this scenario; the documented default is 55)
  • Grate Derate Allowance: 35,000 $ (unchanged)

Working through the calculation

  • Applying the documented formula (Total = wet tonnes x drying penalty x (excess moisture รท 100) + grate derate allowance) to the inputs above produces each figure below.
  • At this operating point the engine returns 280,700 $ for total feedstock moisture impact cost, the number this scenario is built around.
  • At this operating point the engine returns 4.68 $ / piece for feedstock moisture impact cost per unit.
  • At this operating point the engine returns 245,700 $ for variable feedstock moisture impact cost.
  • At this operating point the engine returns 35,000 $ for fixed feedstock moisture impact adder.

How this compares with the baseline

  • Against the tool's baseline example, where excess moisture fraction sits at 55% and the headline result is 249,500 $, this scenario comes in 12.51% above the baseline at 280,700 $.
  • Use it when negotiating fuel supply contracts, sizing a pre-drying investment, or explaining why steam output fell during a wet-weather delivery run. 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 feedstock moisture impact cost: 280,700 $ (headline result)
  • Feedstock moisture impact cost per unit: 4.68 $ / piece
  • Variable feedstock moisture impact cost: 245,700 $
  • Fixed feedstock moisture impact adder: 35,000 $

Run it with your numbers

  • Every input above is editable in the live Feedstock Moisture Impact calculator, which recalculates instantly and can be shared with the inputs intact.

Last reviewed 2026-05-12.