Climate Impact by 2050 of Residential Air-Source Heat Pumps in UK Urban Areas

The UK government promotes residential air-source heat pumps (ASHPs) as a cornerstone to achieving Net Zero emissions by 2050. As climate shifts, ASHP could serve both heating and cooling needs, potentially influencing outdoor temperatures in UK residential neighbourhoods in the future. Here, we use a novel multi-scale modelling framework combining an urban land surface model (SUEWS) and a building energy model (EnergyPlus) to assess the implications of ASHP adoption in idealised low-rise UK residential neighbourhoods under mid-century climate scenarios. Results indicate that ASHP cooling could increase median anthropogenic heat emissions by up to 15 W m^-2 and elevate median local air temperatures by up to 0.12 °C during summer in London. Conversely, in winter, ASHP adoption could reduce anthropogenic heat emissions by up to 19 W m^-2 and lower temperatures by up to 0.23 °C in Aberdeen. While the magnitude of temperature changes may vary across UK cities, the relationship between anthropogenic heat changes and air temperature remains consistent. The findings highlight the importance of balancing indoor and outdoor thermal comfort in the transition to sustainable urban energy systems. This work offers useful insights into the thermal impacts of ASHPs in urban contexts, aiding policymakers and planners in developing climate-resilient strategies.