Abstract
Sustainable development is vital for the future wellbeing of our society. In the energy sector, sustainability involves reforming the energy supply and demand patterns, including using more renewable energy, reducing demand, using energy more efficiently, and changing the timing of electricity use. The three latter issues all involve changes in household behaviours. Studies of energy behaviour began in the 70s after the oil shocks, and the primary focus of studies (then and since) has been on developing models of generalised behaviour. It is evident, however, that there is great variability in household energy consumption. This is not explained either by the physical features of house and appliances, nor by generalised assumptions about everyday behaviours. The lack of detailed knowledge of the heterogeneity of energy behaviours across and within households makes it difficult to develop effective energy behaviour change strategies.
Time-Use Diaries (TUD) are one way of gaining insights into this topic, and are starting to be used internationally as a valuable data-collection method.
This research set out to develop and trial a TUD to collect data about energy-related activities in New Zealand households. Its design was inspired by the Time-Geography approach pioneered by Torsten Hägerstrand. Building on this approach, a TUD was designed to collect data on the everyday energy-related activities of individuals within their households, to meet six pre-defined ‘proof of concept’ criteria.
The TUD was designed iteratively using feedback from 5 households. The refined version was piloted with 22 households in New Plymouth over a period of 7 consecutive days. Participants recorded their energy-related activities, use of specific appliances, changes in temperature settings, and suggestions for improvement. There was 100% completion of the diaries by all eligible household members for the days they were at home, which suggests that the diary format and the support given during the TUD period made it easy for participants to engage. Preliminary analysis of the data revealed different patterns of energy behaviour according to age, gender and household composition, and showed that the TUD produced valid and reliable data. Further analysis (outside of the scope of this thesis) can help identify opportunities for energy efficiency, savings and changing time of use that are relevant to specific household types.
The sampled households received above-average incomes compared to the population in their region, and compared to New Zealanders as a whole. Age-distribution within this study was representative of the New Zealand population for categories under 50 years old. Participants over 50 years were not well represented, as 25% of the New Zealand’s population consists of individuals over 64 years old. Despite encompassing a variety of ages and family sizes, the sample size of this study was relatively small with a high socio-economical income, and therefore cannot be generalised to the population as a whole.