Abstract
This work is motivated by the accelerated pathways to decarbonize our cities. New York City (NYC) is a key example with local law 97 which calls to decarbonize the city by 2050. One of the major sources of carbon emissions is the usage of natural gas and oil for space heating. Air source heat pump (ASHP) systems can replace the natural gas-based heating systems due in large to their deployable in existing buildings. However, a major drawback of ASHP systems is that the performance decreases significantly when outdoor temperature becomes extremely low. It is therefore imperative for comprehensive studies on the performance of ASHP systems in cold climates to determine deployability. In this study, the performance of variable capacity ASHP using R410A refrigerant was investigated in the Northeastern US winter climate, specifically for NYC. A complete laboratory setup was built to simulate the extreme outdoor winter conditions similar to NYC temperatures in January 2022. First law and second law analyses were conducted including a comprehensive exergy analysis. The study reveals that the coefficient of performance (COP) increases from 2.53 to 3.81 when the outdoor temperature increases from 16 °F to 50 °F. The compressor has the highest exergy losses followed by the condenser, expansion valve, and evaporator. The power consumption of the system decreases significantly with the increase in outdoor temperature. This study provides insights into the feasibility and challenges of deploying air source heat pump systems in the NYC winter climates.
