Implications for energy perceptions research

The cues identified in Theme 1 include some that have been found in previous studies (e.g. size, duration of use). Other cues, not previously identified in other studies, were also identified in Theme 1 (e.g. heat produced, perceived energy intensity, age, noise produced, movement produced). A similar qualitative study (using focus groups instead of interviews) that was independently conducted at around the same time also identified the heat produced and perceived energy intensity cues (van den Broek, 2016). Even though no other studies in the litera-ture had previously reported use of the heat cue, in a qualitative study of energy monitor use, Kidd and Williams (2008) reported that participants learnt that ap-pliances that produced heat required the greatest energy intensity to operate. It is possible that previous studies had not reported the heat cue because awareness of the relevance of heat to energy consumption might have changed in recent years. The consistency of the findings with the literature provides support for the findings of the present study and for the approach of taking a more qualitative, exploratory approach to identifying cues. Some of the cues identified in Theme 1 are explored further in quantitative tests in Chapter 4.

Participants’ continued selection of cues in some judgements corresponded with models of heuristic judgements in the literature. Participants considered

additional cues, one at a time, if they could not distinguish between the energy consumption of two appliances based on the first cue (e.g. both appliances pro-duce heat so consider their frequency of use as well). This corresponds with the elimination models of judgements which predict that people use as few cues as possible and consider them one at a time until they can make a judgement, at which point they stop (even if further consideration of other cues might change the judgement) (Berretty et al., 1999; Tversky, 1972). This also corresponds with the conclusions of Schuitema and Steg (2005) who found that only one of their six tested cues was used by their participants in judgements. A rational model of energy judgements would predict that participants consider all the relevant cues at once and weigh them up before making a judgement (Shah & Oppenheimer, 2008). However, most of the time this did not appear to be the case; in some examples, participants were clearly ignoring potentially relevant cues.

Sometimes, participants had to consider more than one cue at once in a judge-ment. When this happened, they had to weigh up which of the cues was most indicative of energy consumption before they could complete their judgement.

Each additional cue considered at the same time in a judgement added complex-ity (and sometimes confusion) to the judgement, suggesting that less information might lead to better judgements, or at least easier judgements, most of the time (Gigerenzer & Gaissmaier, 2011). Newell (2005) and Payne et al. (1993) suggested that people spend more or less effort on judgements according to the context, the task, the individual. It is possible that participants in the present study were encouraged to spend more effort on the judgements than they would otherwise in their daily lives because of the context of the interview. While the interviews were useful for identifying the cues used, further research would need to sys-tematically explore when and how many of the cues are used in specific contexts, including understanding in what situations certain cues are perceived to be more influential than others.

It was not clear whether participants were only using the cues they mentioned and ignoring others, even if relevant, or whether they were implicitly using ad-ditional cues that they did not mention or they might not even have been aware of. For example, in Section 3.3.3.1 in the first judgement by PC05, she mentions size and duration of use, while in the second judgement she mentions heating up and duration of use. Yet, in the second judgement it seems possible that she is actually considering size as well but that the size of the appliance is much the

same for the three appliances she is considering. She could be inferring that large kitchen appliances that produce heat and are used for longer durations of time consume more energy. This question of whether participants are actually consid-ering additional cues that they are not aware of or just do not mention is relevant throughout the whole of this analysis and is acknowledged as a limitation of the method.

Previous quantitative research had emphasised the importance of size as a cue in participants’ judgements (Baird & Brier, 1981; Schuitema & Steg, 2005). In the present interviews, while most participants mentioned or implied that they used size to some extent, they often seemed to use it in conjunction with other cues, rather than by itself. For example, although PC06 emphasised the size of her car when first writing it down on a card, when she was actually inferring the consumption of the car, she talked about its usage as well. It is, of course, possible that in making a snap decision about the car’s consumption, she would have based her inference solely on its size but when given time to think and discuss it in the interview context she considered other cues.

Some cues seemed to be combined with other cues that were then used to infer energy consumption. For example, two participants also explained that they used size to infer the amount of water, air, or food that needs heating up and, therefore, the amount of energy needed to produce that heat. Although Schuitema and Steg (2005) concluded that size was very clearly used on its own to infer energy consumption of appliances, it actually seems that making inferences about energy consumption is more complicated than that. Multiple cues can be involved, as Baird and Brier (1981) speculated might be the case, perhaps even to infer other cues that are then used to infer energy consumption.

The findings presented in Theme 2 correspond with findings by van den Broek (2016) whose participants claimed to be aware of using nearly three cues in each judgement. Although she concluded that this was unlikely to be the case (for rea-sons of complexity), the findings from the present study suggest it might be the case, at least sometimes. Some participants in Kidd and Williams (2008)’s quali-tative study on use of energy monitors were surprised by spikes in consumption by appliances such as kettles, electric showers, and hair dryers, yet some (maybe the same people; they did not say) recognised that the amount of time that the appliance is on or in use is also important. It seems that householders recognise the complexity of making judgements about energy consumption. It makes sense

then that they try to save effort by simplifying their judgements with heuristic strategies, but it seems they are sometimes torn between wanting to make more

“rational” judgements (including as much relevant information as possible) and making more heuristic, simpler judgements (ignoring as much information as possible).

3.4.2.1 Representative sampling

The participants in the present study were householders (mainly home-owners) who lived in a large village near to the researcher. This ensured that it was pos-sible to schedule and conduct the interviews around part-time employment over a period of three months. As householders rather than university students, the study was fairly representative of UK householders because they were mainly home-owners or longer-term renters than students typically are, and they were fully responsible for paying energy bills, which students in university accommo-dation tend not to be. There are obviously limitations on its representativeness, however, in that the participants were all white, living in a semi-rural village, and appeared reasonably well educated and engaged in thinking about energy con-sumption. The sample was not nationally representative and further interview studies would need to be conducted with different demographics to establish whether the findings are generalisable to the UK population.