Modelling Occupant Behaviour in Passivhaus Buildings: Bridging the Energy Gap

CIBSE Technical Symposium, DeMontfort University, Leicester UK
6th and 7th September 2011

The UK Government’s target of zero-carbon homes from 2016 has generated a wave of ambitious building projects, with low ‘in-use’ energy consumption as a key target. The performances of such projects, however, are all too often poorer than predicted in design. In part, this may be attributable to occupant behaviour and household variation. It is important to attempt to identify the sensitivity of concepts such as Passivhaus if they are to be successfully adopted, both geographically and socially. This paper addresses the possible range of occupant behaviour and the resultant impact on heating energy consumption for domestic buildings of this kind. Stochastic profiles for different occupancy patterns, lighting, and appliance-use were applied to a set of 100 terraced Passivhaus units, and modelled in a dynamic building simulation program. Preliminary comparisons indicate strong correlations between the modelled and measured data. Multiple regression techniques were used to identify the relationship between space heating load and behavioural variables such as thermal preference, door and window opening, appliance-use, and occupancy patterns. This leads to a regression equation which can be used to effectively estimate the likely space-heat requirements of a household given particular behavioural variables.