Moisture Content, Calorific Value, and Fuel Blending
In industrial biomass combustion, moisture is often the hidden driver of poor performance. The same truck weight can carry very different usable energy depending on how much of that load is water.
Why Moisture Matters
Water does not burn, but it still occupies payload. As moisture rises, net usable heat per tonne falls quickly.
Why Basis Matters
Wet basis and dry basis are not interchangeable. If teams mix them up, fuel specs can look better than real plant performance.
Why Blending Matters
Most plants blend streams. A small fraction of wet chip can pull down the final blend quality and truck energy content.
Wet Basis vs Dry Basis
Wet basis moisture means water as a percentage of total wet mass. Dry basis moisture means water as a percentage of dry solids. The dry-basis number accelerates sharply at high wet moisture.
Example: 50% wet-basis moisture equals roughly 100% dry-basis moisture.
Moisture Conversion Tool
Energy in Wood vs Moisture Content
Forestry baseline curve with operating zones from dry process fuel through to very wet green fuel.
Two-Stream Fuel Blending Tool
Fuel A
Fuel B
Water Penalty Visual
For each 1 tonne of blended fuel, this shows how much is water, how much is dry matter, and the educational evaporation burden estimate.
Water in load
400 kg
Dry fuel in load
600 kg
Evaporation burden
0.25 MWh/t
Per Tonne and Per Truck Output
Blended wet-basis moisture
31.0%
Blended dry-basis moisture
44.9%
Blended NCV
3.33 MWh/t
Energy in 1 tonne sample
3.33 MWh
Truck size assumption
26 tonnes
Energy per truck
86.6 MWh
Delivered Fuel Cost Estimator (p/kWh)
Many biomass offers are quoted as £/tonne at a stated moisture. This block converts that into p/kWh and separates fuel cost from logistics cost.
Single Fuel Scenario
Assumption: 1 delivery per day.
Estimated NCV at selected moisture
2.30 MWh/t
Tonnes per delivery
25.0 t/delivery
Fuel component
0.00 p/kWh
Logistics component
0.00 p/kWh
Total delivered cost
0.00 p/kWh
Energy delivered per day
0 kWh/day
The chart is intentionally simple: one stacked column showing fuel p/kWh plus logistics p/kWh for your current single-fuel assumptions (with one 100 m3-class delivery per day).
Want Help Optimizing Fuel Blend and Cost?
Ranheat engineers can support moisture control, blending strategy, and fuel cost optimization for your plant.