System-level techno-economic comparison of residential low-carbon heating and cooling solutions

Abstract

This paper studies portfolios of electricity- and hydrogen-driven heat pumps, electricity- and hydrogen-driven boilers and thermal energy storage technologies from an energy system perspective. Thermodynamic and component-costing models of heating and cooling technologies are integrated into a whole-energy system cost optimisation model to determine configurations of heating and cooling systems that minimise the overall system cost. Case studies focus on two archetypal systems (North and South) that differ in terms of heating and cooling demand and availability profiles of solar and wind generation. Modelling results suggest that optimal capacities for heating and cooling technologies vary significantly depending on system properties. Between 83 % and 100 % of low-carbon heat is supplied by electric heat pump technologies, with the rest contributed by electric or hydrogen boilers, supplemented by heat storage. Air-to-air electric heat pumps emerge as a significant contributor to both heating and cooling, although their contribution may be constrained by the compatibility with existing heating systems and the inability to provide hot water. Nevertheless, they are found to be a useful supplementary source of space heating that can displace between 20 and 33 GWth of other heating technologies compared to the case where they do not contribute to space heating.