Abstract
With increasing adoption of photovoltaic solar panels (PV) for electricity generation by households, resulting new patterns of generation and consumption may affect the operation of local and national grids. Existing research on the impacts of PV adoption on consumption patterns shows a high degree of variability, which may be partially due to the methods used, including a reliance on small samples and self-reports. This thesis brings a multi-method methodological approach to exploring differences in consumption patterns before and after PV adoption across two sets of households in New Zealand with different PV configurations. It examines changes in consumption at the meter, as well as changes to households’ energy cultures – i.e., their norms, practices, and material assets.
The dissertation seeks to answer three questions: “What changes in measured net electricity consumption can be observed after the adoption of solar PV?” (RQ1), “What changes in electricity consumption behaviour of household occupants occur after the adoption of solar PV?” (RQ2) and “What are the implications of changing energy cultures for patterns of net electricity consumption?” (RQ3). To do so, it draws on both qualitative and quantitative data. At least one year of half-hourly residential net electricity consumption data was obtained for 222 households, of which, 119 owned their PV and 103 had a lease arrangement. Statistical analysis using R software was used to address the first research question. Semi-structured interviews were undertaken with 17 PV owners and 23 PV leasers to inform the second research question. The interview design and analyses were guided by the energy cultures framework. This then enabled a discussion addressing the third research question.
Net electricity consumption, measured at the meter, changed both as a direct influence of the new PV electricity generation, and also in indirect ways (e.g., through temporal load shifting) (RQ1). Results showed that the new patterns of electricity import from the grid were not solely driven by the feed-in of electricity generated by the PV during the day but were also affected by a changing energy culture. Householders’ norms, practices and choices of new technologies altered after the adoption of PV, including increased environmental awareness, load matching and shifting, and increased energy efficiency in both materiality and practices (RQ2). This led to altered patterns of electricity import from the grid that could be identified in the half-hourly consumption data. Adjustments in both time of use and net consumption were identified at different timescales, from daily patterns to seasonal and annual consumption. This change in energy culture has implications on grid stability and reliability, thus impacting stakeholders in the electricity sector (RQ3).
This dissertation extends the knowledge on the effects of PV adoption on residential net electricity demand by drawing on both qualitative and quantitative analyses and using an energy cultures framing. It contributes to international literature investigating changes after the adoption of PV, providing new knowledge on what drives the changes in net demand at the meter. With the increasing ubiquity of PV, this work can assist in grid management, policy development and system planning to ensure that future electricity systems take account of the subtle but important changes to energy cultures within households that adopt PV.