Experimental Results of a Gas Fired Adsorption Heat Pump and Simulative Prediction of Annual Performance in a Multi-Family House

Abstract

• Development of a functional prototype of a SAPO-34-water gas adsorption heat pump. • Analysis of low-temperature heat sources ‘borehole heat exchanger’ and ‘exhaust air’. • Measurement includes sensors to calculate the energy balance of each component. • Calibration and validation of component models and of the functional prototype. • Transient annual simulation of GAHP within heating system with Modelica/Dymola. Gas driven sorption heat pumps can be an efficient alternative to conventional gas condensing boilers for heating buildings. Measurement results of a functional prototype of a gas adsorption heat pump with 40 kW nominal capacity and the SAPO-34-water working pair are presented. The innovative adsorption heat exchanger is directly crystallized applying the partial support transformation technique. A transient lumped-parameter model of the gas adsorption heat pump is developed. For the first time, it is possible to perform an annual simulation of the GAHP within the heating system of a multi-family house with full adsorption dynamics based on calibrated and validated component models. This annual performance calculation is carried out for the two different low-temperature heat sources geothermal heat (bore hole heat exchanger) and exhaust air. Using exhaust air as low-temperature heat source for a GAHP is an entirely new approach that is evaluated in this study. Compared to a gas condensing boiler, the annual gas consumption is reduced by 22 % for the case of bore hole heat exchanger and by 27 % for the case of exhaust air as low-temperature heat source for a building with heating circuit design temperatures of 45 °C/35 °C.