Combining energy efficiency measure approaches and occupancy patterns in building modelling in the UK residential context

The UK faces a significant retrofit challenge, especially with its housing stock of old, hard-to-treat solid walled dwellings. In this work, we investigate the delivery of heated thermal comfort with a lower energy demand through four types of energy efficiency interventions: passive system, conversion device, method of service control, and level of service demanded. These are compared for three distinct household occupancy patterns, corresponding to a working family, a working couple and a daytime-present couple. Energy efficiency measures are considered singly and in combination, to study whether multiple lower cost measures can achieve comparable savings to higher cost individual measures. Scenarios are simulated using engineering building modelling software TRNSYS with data taken from literature. Upgraded insulation of wall and roof resulted in highest savings in all occupancy scenarios, but comparable savings were calculated for reduced internal temperature and partial spatial heating in scenarios in which the house is not at maximum capacity. Zonal heating control is expected to achieve greatest savings for the working couple who had a flexible occupancy pattern. The results from this modelling work show the extent to which energy consumption depends on the appropriate matching between energy efficiency measures and occupant type.