A probabilistic approach to include the overall efficiency of gas-fired heating systems in urban building energy modelling

Abstract

Abstract Urban building energy modelling has an essential role in the estimation of energy demand at urban or neighbourhood scales. However, current modelling methods have limitations in reproducing realistic gross energy usage. Although it is theoretically possible to simulate all components of the heating system in detail, such an extensive approach significantly increases the computational effort, prohibiting a large scale probabilistic analysis. As an alternative, this paper presents a simplified data-driven approach to estimate the overall efficiency for the six most occurring gas-fired heating system configurations in Flemish single-family dwellings. For all configurations, efficiencies of emission, distribution, production, control and storage components are taken into account, of which the efficiency of the production unit is modelled most in detail as it includes the load-dependency. The approach is applied to a sample of 20 dwellings reflecting realistic variation in size, insulation quality and occupancy schedules. For all dwellings and the different heating systems the resulting annual production efficiency, and monthly heating systems’ efficiency as a function of gross energy demand are shown based on the 25th, 50th and 75th percentile.