Better home energy audit modelling: incorporating inhabitant behaviours

Building energy modelling is often used in US home energy audits to assess a home's energy performance and to determine energy-efficiency retrofit recommendations. These models promise quantitative, engineering-based, defensible information on a home's energy retrofit opportunities. Modelling is based on assumed standard use behaviours, despite highly variable energy use practices. This research reports on tests that incorporate household behaviour in home energy audit modelling, based on a sample of single-family households that received a utility-sponsored home energy audit in Seattle, Washington, a US city with a cool temperate climate. The use of a compact set of self-reported behaviours in place of standardized behavioural assumptions improved the match between actual home energy consumption and model estimates, and shifted retrofit savings predictions. These were modest improvements over the initially poor match, but highlight the opportunity for better customizing home energy audit modelling by using simple information on household behaviours. A comparison of modelled savings of heating-related conservation actions shows that energy savings from moderate behavioural changes are on par with retrofits for many homes. These steps provide a gateway to modelling household behavioural changes alongside retrofits, and a means to bring behaviour into conversations with homeowners and into the technically oriented efficiency paradigm in general.