Per-appliance energy feedback as a moving target Omar Shafqat Dept. of Energy Technology Royal Institute of Technology KTH Stockholm, Sweden omars@kth.se Erik Rosberg, Cristian Bogdan, Anders Lundström Dept. of Media Technology and Interaction Design Royal Institute of Technology KTH Stockholm, Sweden cristi@kth.se Abstract— Energy feedback through interactive technologies is often proposed as a major approach to reduce household energy consumption and carbon footprint. However, this vision is chal- lenged by critics. This paper seeks to inform this debate through a case study of an advanced energy feedback device providing runtime and de-aggregated per-appliance feedback through a smartphone app. This study, based on 15 contextual interviews, aims to investigate how users understand and act on the various levels of feedback received from the device and the resulting im- pact on user behaviour. We found that appliance detection can be a “moving target” that hampers the intended aims of energy feedback, as it reduces user understanding of the technology. The lack of understanding was further deepened by unrelated sup- plementary functionality added in the package, in the form of smart plugs. Despite gaining a better understanding of their en- ergy consumption, the users felt limited in terms of their ability to change their behaviour considerably. Author Keywords: Energy feedback; Home energy management; user behaviour; de-aggregated feedback. I. INTRODUCTION In Europe, households account for 25% of the energy- related greenhouse gas emission [6]. Household energy con- sumption and energy efficiency thus have high saving poten- tial, making it an important target area for policy makers [13]. Currently, IoT based Home Energy Management Systems (HEMS) are gaining popularity by providing high resolution information, control, and automation possibilities to end-users [2]. According to Burgess [3], energy is so-called ‘double invis- ible’ to households. Firstly, it is an abstract and invisible force and, secondly, it is a part of inconspicuous routines and habits. This also means that it is difficult for people to connect activi- ties to energy consumption [11]. Before smart meters, house- holds consumed energy within an information void [4], una- ware of how much and when different appliances used energy. Energy feedback brought by (e.g.) smart meters is a key component for achieving behavioural change [9] and reducing carbon footprint [4]. Hence it is also a means to overcome en- ergy’s ‘double invisibility’. However, the effect of real-time energy feedback is not as simple as cause and effect as energy feedback may be complex to understand and use in practice. In this paper we look at energy feedback from the perspec- tive of per appliance, or de-aggregated, feedback. The paper addresses the per-appliance feedback based on issues found in previous research on energy feedback [7], [8]. The study is a result of a deployment of the state-of-art smart energy monitor Smappee in two different areas in a Scandinavian city. In total, 25 units were installed and 15 users were interviewed for the purpose of this study. The aim of this paper is to explore how users of the de- aggregated feedback device called Smappee act upon its ser- vice. The goal is to address the following research questions: • [RQ1] Does Smappee de-aggregated feedback contrib- ute to a better understanding of users’ energy con- sumption? • [RQ2] Does Smappee de-aggregated feedback contrib- ute to an energy behaviour shift? And if not, what are the main causes preventing it? The study found that despite improving the users’ under- standing of their energy consumption, the impact on savings was limited due by the effort required from the users. The “moving target” aspect of appliance labelling led to users los- ing interest. Additionally, a majority of users quoted a lack of time in order to fully utilize the device. II. RELATED WORK Various studies have been conducted within the area of smart meters and their influence on user behaviour [22]. Cur- rently, there is little research on de-aggregated feedback, yet according to Hargreaves [1] users wonder about energy con- sumption of each appliance. In Hargreaves study, household- ers turned appliance on and off, checked the total (aggregated) consumption change, and made estimations of how much vari- ous appliances consumed. This is pressing as de-aggregated feedback is the only way of providing a direct link between actions and results [2], hence brings awareness of peoples ac- tions. A determining factor for the success of feedback on behav- ioural change is the initial motivation of the users [3], [4]. With low motivation, the system will typically remain unused. Kel- sey [5] concluded that the major motivation is financial and that the users that are most motivated are the users who are in charge of the household’s electric bill. One result that is quite common is that it is usually the man in the household that is motivated and takes charge of the energy feedback system [1], [4], [6]. Users tend to lose interest in the feedback after a while [1], [5], [7], [8]. However, according to Kelsey [5] that could be avoided if the feedback constantly changes in a way that makes the user experience always new. Hargreaves [8] found that the