Heat Supply Temperature Impact on the Seasonal Cost of Low Carbon Domestic Heat Pump Technology

In this study the economic analysis of a 9kW variable speed compressor-based air source heat pump (ASHP) has been carried out. The HP system, developed with an aim to meet typical UK household heating demand for retrofitting application, was tested in the lab as per BSEN14511 standards at various constant definite heat load under steady state conditions. The thermodynamic performance of the HP is presented at nominal value of 9kW. The test house seasonal heating load demand was fulfilled at three constant water supply temperature (WST) of 35^o C, 45^o C, and 55^oC and the HP seasonal electric power consumption, cost, and carbon emissions were calculated. The HP average efficiency at supply temperatures of 35^o C, 45^o C, and 55^o C over the same ambient temperature conditions was found to be 363%, 291%, and 212% for meeting the house load demand completely by varying operating compressor speed. A comparative study of cost, carbon emission, and energy savings with other heating technologies, i.e. gas/oil boiler, electric heater is also conducted and presented.