Dynamic modelling of interactions between building heating events

Abstract

With high energy prices, more households in fuel poverty and space heating accounting for significant amounts of global CO2 emissions, every effort is required to improve the efficacy and efficiency of building heating systems. There is an opportunity to reduce global CO2 emissions and energy demand within domestic and commercial applications by better utilising heating events. During periods of inactivity, setpoints are often reduced to conserve energy. This decreases building fabric temperature, which must be restored during working hours. This paper quantifies how heating events interact, specifically considering their contribution to subsequent heating events to inform decisions on heating schedules. Using a validated dynamic room model representing a typical UK domestic property, the relationship between room temperature, room temperature history, building fabric and surrounding conditions on the coupling of adjacent heating events was explored. The amount of energy that is usefully retained for the subsequent heating event depends significantly on the duration of the previous heating and cooling periods. For example, a day-long heating event with four heating periods of 1.5 hours (duty cycle of 0.25), consumes 9.4% more energy than a single 6.0 hour heating period. A small energy pulse was used in the model to track the interactions between specific heating events. It showed that the useful contribution of a heating event to future heating events depended on the time temperature history of the room, due to the dynamic thermal behaviour of the building fabric.