This paper investigates the use of actual monitored household energy as an indicator of the thermal efficiency of a dwelling and subsequently rating of the building thermal performance. The paper reviews evaluation methods used internationally for both building thermal efficiency and building energy labelling and presents results from two discrete studies in South Australia on monitoring actual household energy consumption.
In order to investigate the occupancy effect on household energy, monitored energy data collected from two different housing developments in South Australia were examined. The energy ratings for these homes are compliant with the national agreed protocols for thermal performance modelling of dwellings, where one set of homes is a group occupied by higher socio-economic groups and the other is low income public housing in a colder climate region with much poorer home energy ratings. The wide variation of actual household energy for the homes that have relatively similar thermal envelopes indicates a lack of meaningful use for actual household energy in disclosure of house energy performance. Therefore, it is argued that thermal modelling software used to rate homes appears a more useful application of a system of disclosure of energy performance than the use of energy bills.
Keywords: Monitored energy use; Home energy rating; Housing energy disclosure