Experimental study and feasibility analysis of gas absorption heat pump applications in Canada

The feasibility of a Natural Gas Absorption Heat Pump (GAHP) was assessed using an Excel-based technology screening tool that incorporated performance curves evaluated experimentally. The GAHP unit was installed at the Toronto and Region Conservation Authority's Archetype Sustainable Houses (ASH), and its heating and cooling capacities, Gas Utilization Efficiency (GUE), Coefficient of Performance (COP), and economic-environmental performances were analyzed. The GAHP's performance during the cooling season aligned with expectations. However, in the heating season, its effectiveness significantly declined at outdoor air temperatures below - 1.5 °C, rendering it less efficient than other natural gas-based technologies. This significant decrease in heating efficiency during extreme cold raises concerns about its practicality for use in Canadian houses. An Excel-based screen tool was created with a validated performance curve to assess the feasibility of the GAHP in five major Canadian cities (Toronto, Montreal, Halifax, Edmonton, and Vancouver). Vancouver achieved the highest GUE at 108%, while Edmonton had the lowest at 90%. Only Vancouver exceeded a GUE of 100% using a 50% Propylene Glycol (PG)/water mixture. During the cooling season, the GUE was about 58% for all chosen cities. Compared to an Air Source Heat Pump (ASHP), the GAHP offers lower operational costs, particularly with fluids with better heat transfer capabilities. Although GAHP is a promising technology, more experimental data is needed to assess its relevance fully in the context of the Canadian climate.