This research presents the design and evaluation of an intervention that introduces modification of time perceptions as one of the solutions to promote sustainable behaviours. It is demonstrated in this thesis that unnecessary energy use is often caused by temporal tensions, defined as the relation between actions to be performed and available time. This research proposes that it is possible to deliberately reduce temporal tensions, and this can motivate people to behave more sustainably. Persuasive technology and human-computer interaction provided the tools needed to manipulate time perceptions and therefore bring about changes in the specific behaviours that result in unnecessary energy usage.
Previous studies indicate that behaviours play an important role in energy consumption. From the different domains of energy use that could be examined, cooking was chosen to be the platform where the studies on behaviour change and energy use would take place. How behaviours influence energy use motivated the design of empirical studies to understand behaviours related to domestic energy use and identify what are the determinants of these behaviours. Each determinant was related to a strategy to be included on a behaviour change intervention. A wider survey was developed to understand students acceptance of a set of proposed energy saving techniques, and resulted in a vast volume of information about user preferences and intentions to perform the suggested energy saving behaviours for cooking. It emerged that participants rushed into the cooking tasks without much deliberation, consequently not following preparation procedures and thus using more energy. Information gathered during the first studies also showed that participants behaviours were partially motivated by the need to speed up the cooking process in order to reduce boredom when they were waiting for the food to cook, consequently resulting in extra energy usage.
The knowledge gathered from the preceding steps and a literature review informed the design of strategies to modify the non-sustainable behaviours and promote energy saving. A user-centred design process involving an idea generation session and scenario analysis was used to provide a set of strategies to be embedded in an intervention, containing the specific methods to tackle the correspondent determinants of behaviours. The specific needs of the cooking activity indicated that an electronic intervention was an adequate platform to be implemented and tested. Two high resolution working prototypes of the electronic interventions were developed as mobile phone applications. The final study comprised the evaluation of the proposed interventions in improving aspects of the cooking activity, the acceptance of the interventions and effectiveness in promoting energy saving.
A Doctoral Thesis. Submitted in partial fulfilment of the requirements for the award of Doctor of Philosophy of Loughborough University.