Performance and Emissions Evaluation of Absorption Refrigeration Cooling from Biomass Waste Heat

This paper presents an investigation into the utilisation of biomass waste heat. A biomass boiler is used to generate hot water of which the excess heat is used to drive an absorption cooling unit. The emissions and performance are measured and compared for single generation of heating and cooling and a combined mode of heating and cooling. The tests are conducted for various Reynolds numbers to represent different pump regulating settings. The tests showed a coefficient of performance for cooling (COP) of 0.30-0.60 depending on Re which is similar for the absorption unit when driven on solar energy. The utilisation factor for heating only compared to combined heating and cooling increased on average from 0.40 to 0.85 depending on operating parameters. The tests showed that absorption cooling is a viable option to increase the energy utilisation factor for biomass boilers and the use of biomass as a top up for solar cooling when there is a lack of solar energy.