Present boiler details

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Fill out this form with the details of your present boiler (assumed to be running on either natural gas, fuel oil or coal) and it's annual fuel consumption. This calculator uses the calculated energy content of the biomass (for more details see the Biomass calorific value calculator) and the standard efficiency of a biomass boiler to determine the heat that can be produced by the biomass. This is compared with the heat produced in the current system to determine the percentage that can be replaced by the biomass. A number of assumptions are made in this calculation including the calorific value of the biomass and natural gas, fuel oil or coal and the system efficiencies.

The equation to determine amount of heat from burning the biomass and the heat from burning the current fuel is given by:

The boiler efficiencies used in this calculation are given here

Last modified: Thu Dec 14 17:19:39 New Zealand Daylight Time 2006