This research study investigates the effects of the large-scale installation of domestic heat pumps on the UK electricity supply over the short to medium term. A BREDEM-based dwelling energy model, incorporating a model of heat pump performance, is enhanced for the effects of varying monthly temperatures. Data from the English Housing Survey (2007) are analysed using this model to estimate electricity consumption to 2020 and 2050, and simulate scenarios for replacing existing heating systems by ground or air source heat pumps. The type of heat pump (ground or air source) is determined by dwelling plot dimensions data from the EHS. Modelling results for 2020 showed that a policy of replacing the heating systems with the highest emissions could reduce or at least minimise the increase in electricity consumption and carbon emissions. Results for 2050 showed that replacement of some 80% of current gas-fired systems would enable the UK to meet its target of 80% carbon emissions reduction in this sector when accompanied by simultaneous decarbonisation of the electricity supply. These results provide some support for the UK government's policy of subsidizing heat pump installations through the Renewable Heat Incentive payments while indicating that meeting emission targets requires far greater adoption of these systems than current ambitions. (C) 2014 Elsevier B.V. All rights reserved.