A unified model for the simulation of oil, gas and biomass space heating boilers for energy estimating purposes. Part I: Model development

A unified model for the simulation of oil, gas, pellet and wood chip space heating boilers for energy estimating purposes has been developed based on a literature review and laboratory measurements on four different boilers. The model includes the influence of space heating return temperature, power modulation and condensation gains on the flue gas losses of the boiler, the simulation of a thermal boiler capacitance including its heat losses during standby and operation, and the ability to calculate carbon monoxide emissions and electricity use dependent on power modulation and number of burner starts. Some of the new features of the presented boiler model are the unification of models for oil, gas and biomass boilers into one model, and the combination of steady state calculation for the flue gas to water heat transfer with an explicit solution for the time dependent temperature change of the boiler's thermal capacitance.