Research on interventions aimed to promote energy savings has shown support for direct feedback using in-home displays (IHDs) to reduce energy consumption. These displays are electronic devices that provide real-time energy information and are emerging as an effective tool to communicate with people about their energy consumption. How feedback is presented to people and how they understand the meaning of such feedback largely depends on the design of the display, yet there are relatively few studies that investigate the way in which the display can best be designed to present energy information and motivate energy-saving behaviour. Further, even though there is a wide range of variations in the visual presentation of feedback, there is a lack of focus on the process of optimising the IHD design. This thesis aims to address the need for designing IHDs at the display component level, by examining three types of display design (numerical displays, analogue displays using speedometer dials, and ambient displays using emotional faces) in both laboratory-based computer-simulated experiments and field-based experiments: participants’ abilities to detect changes in energy information shown on the computer-simulated displays were measured by means of accuracy rate and response time, and their subjective preferences for display types were assessed against experimental data; live energy data were displayed using the three design types in a student residence at the University of Bath to see how they would influence energy-use behaviour.Results from the laboratory experiments demonstrated that both accuracy rate and response time for seeing changes in the information displayed were strongly associated with the type of display design. Participants preferred numerical display and were better at detecting changes in information with this display than with the other two. Conversely, the student residence experiments showed that when participants’ attention was divided in a household setting, there was no difference in energy consumption among experimental groups who received information from any of the three display types. However, these experimental groups used significantly less energy compared with control groups, who had no displays installed. It was concluded that 1) the mere presence of a display device could influence people’s behaviour, regardless of the type of display design, people’s preferences or the level of user engagement with the display, although there was a strong indication that the ambient design worked better than the other two designs at an arbitrary statistical significance level of 0.95, and 2) subjective preferences and computer-simulated studies are poor guides to the actual performance of IHDs in real-world settings.This work helps establish how IHDs can be designed and the influence that they may have on people’s energy-consumption behaviour. It also contributes to the literature of exploring people’s perceptibility of energy information. The method used is replicable and can be applied in similar studies on energy display design. Lastly, the improved understanding gained through this work will facilitate the development of effective smart meter display technology that may help people adopt conscious energy behaviour in the long term.
|Date of Award||24 May 2015|
|Sponsors||University of Bath|
|Supervisor||Sukumar Natarajan (Supervisor) & Ian Walker (Supervisor)|
- energy use
- in-home display
- interface design optimisation
- behavioural change