Biomass calorific value calculator

Use the following calculator to help you determine the energy content, or calorific value, of your woody biomass fuel. For more details about the effects of moisture content on the calorific value of biomass, see below. A more advanced calculator allows for the specification of the moisture / water content.

(dry basis)
(wet basis)
(dry basis)

(wet basis)

Oven-dry woody biomass typically has a calorific value of 18-21 MJ per kg on a dry basis (this is the gross calorific value).

Chart - Net Calorific value for Water Content
Chart - Net Calorific value for Moisture Content

Most fuels are not oven dry when burnt and the water in the wood must be evaporated, detracting from the extractable energy* (or net calorific value). Moisture or water content is the single biggest factor in the variability in combustion behaviour of woody biomass. The following figure shows the dependence of net calorific value on moisture content (dry basis) and water content (wet basis).

(dry basis), typically 18-21 MJ/Kg
(wet basis), typically 10% - 60%
(dry basis), typically 6%

(wet basis)

The theory behind this calculator is described here.


This calculator was developed by, and remains the property of, the New Zealand Forest Research Institute Limited and is licensed to EECA for use on this website. Neither EECA nor New Zealand Forest Research Institute Limited accepts liability for any damages or losses arising from the use of this calculator. Use of the calculator, and application of information gained from the calculator, is done entirely at the users own risk.