David Whaley

ABSTRACT With policy directions firmly moving towards net zero energy homes, what do we know about the perceptions and experiences of households who already live in homes at or near that standard? The research sets out to determine whether householders believe these buildings are thermally comfortable, and if they feel confident operating the smart technologies that help achieve the net zero energy outcome? Combining interviews from 25 households and monitored energy data from over 50 near zero energy homes, this paper examines the validity of this policy goal from the building user perspective. The evidence shows households attain high levels of thermal comfort, enjoy lower energy bills, and believe their behaviour has been influenced by the building and its energy systems. Yet many remain concerned that the building industry is unable to produce homes that maintain thermal comfort in all spaces and all seasons. The residents have also identified significant issues in the reliability and usability of the energy technologies. Whilst the policy appears valid from the end-user perspective, the case study highlights the substantial task ahead for policy makers to establish suitable commissioning and compliance processes, and develop effective energy rating tools on the path to zero energy homes.

ABSTRACT Building energy policy in many countries is firmly pointed towards a need for net zero energy homes. But given the limited range of operational energy impacts that can be directly influenced by building regulations, and the wide variation in energy use behaviours of building users, what system performance levels will be required to ensure new homes achieve that standard? This paper utilises in-home energy monitoring from a near net zero energy estate to provide the evidence of the system performance needed for all major end-uses, for homes in warm temperate climates to achieve, on average, a net zero operational energy standard. The evidence presented in this paper points to the combination of passive solar design strategies, energy efficient appliances, and active solar systems that will lead to net zero energy performance given contemporary lifestyles and the impact of the digital age.

ABSTRACT Many countries are searching for ways to reduce the energy and carbon impact of housing. The terms net zero-energy home and net zero-carbon home have entered the policy lexicon, without clear definitions and without widespread understanding of the likely policy impact. Is the concept limited to bespoke architect driven buildings for specific green clients, or does it have relevance in the mainstream house building sector and for typical households? When we consider volume house building and contemporary lifestyles, what is the energy end-use reality of so called zero-energy homes? Can government policy instruments deliver housing estates that are thermally comfortable, energy efficient and powered by renewable energy?