A passive house with seasonal solar energy store: in situ data and numerical modelling

This paper presents parametric analysis of solar collector area and solar energy storage volume for a passive house in Galway, Ireland. Using the simulation tool Transient System Simulation Tool (TRNSYS), a model was developed to represent a 215 m2 home built to Passivhaus standards and incorporating a 10.6 m2 solar thermal collector and a 23 m3 solar thermal storage tank. This model was validated through comparison with data collected in situ from the operation of the home over the period of 1 year. Once validated, the model was used to investigate the effect of varying solar collector area and solar energy storage volume on the fraction of heat demand met by solar energy. Results indicate that increasing collector area from 10.6 to 20 m2 could increase total solar fraction from 0.47 to 0.63, decreasing fossil-fuel-derived energy demand at the home under study by a further 30%.