Tangible Energy: Providing Insight into Energy Consumption through Repeated Deliberate Gestures First Author Name (Blank if Blind Review) Affiliation (Blank if Blind Review) Address (Blank if Blind Review) e-mail address (Blank if Blind Review) Optional phone number (Blank if Blind Review) Third Author Name (Blank if Blind Review) Affiliation (Blank if Blind Review) Address (Blank if Blind Review) e-mail address (Blank if Blind Review) Optional phone number (Blank if Blind Review) ABSTRACT
In this paper we discuss the role of tangible interaction as a means of understanding one’s personal energy consumption and the consumption of different electronic devices in relation to each other. We present a tool that uses the metaphor of a traditional charcoal briquet, called “EBriquet”. It is used as an energy unit with a certain capacity that has to be refed into the system when its capacity is exhausted. We argue that, by means of this repeated gesture, awareness of energy consumption is created. In qualitative interviews we tested and discussed our prototype with a group of 10 respondents. Author Keywords
Tangible, energy awareness, gesture, electronic device, household ACM Classification Keywords
H5.2. User Interfaces: Interaction Styles
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brought with it a better management of energy consumption in households. However, these Smart Meters have some noteworthy deficiencies connected with them [3]. Among them is the abstract form in which energy consumption is communicated. Usually only numbers indicate how much energy is used in a household. We argue that it is especially important to provide a physical experience of the consumption of devices in one's home. This way energy consumption could come to the user's notice in a much more deliberate way. Prompting the user to conduct a certain bodily gesture over and over again to be able to use energy could help moving the whole consumption into focus and prevent thoughtless usage of devices, like, for example, a running TV while nobody is in the room. Also, for one thing it is important to provide the user with a direct comparison of consumption between devices he's interested in to identify major energy consumers, for another thing the user should have a
INTRODUCTION
Global warming continues to get more and more attention in international media and with it the need for sustainable behavior and a reduction of the carbon footprint has increased over the last couple of years. Additionally the costs for energy are growing constantly. Due to that fact, people’s concern with a reduction of their energy consumption continues to gain weight [1][2]. The introduction of so-called Smart Meters some years ago Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. TEI ‘11, January 23–26, 2011, Funchal, Madeira, Portugal. Copyright 2010 ACM 978-1-60558-246-7/09/04...$5.00.
Figure 1: The whole system with E-Briquet and box with slot
realtime display of the energy a given device consumes, while it's running. Therefore our approach was to provide users with a tool that incorporates these three points. PROTOTYPE
Goal of our working prototype was to be able to discuss our design in a user study. When developing our concept, we especially put emphasis on the use of a metaphor that is connected with a known tangible action. We considered the charcoal briquet to be a promising metaphor since most people can relate to it and see it as an energy unit that holds a given amount of energy and has to be replaced when it’s burned down. Additionally we thought it was important to convey an impression of depletion of the E-Briquet when it is in use. The prototype consists of the aforementioned EBriquet, a small cuboid with a small digital number display on top that informs about the number of times it has been used and a small box. We defined a capacity of one kilowatt hour for the briquet. With that amount of energy you would use 1/8 of a briquet in one hour, while you would need 1.5 E-Briquets for the washing machine in the same time. It is important to note that the briquet doesn’t actually “hold” energy, it merely allows the flow of energy, when it is active. It is used together with a box with a slot in it on both sides. To use energy for running a device you have to stick it into the slot. By doing this, energy becomes available for the connected device and the E-Briquet is drawn into the device, obscuring more and more of it. The part that can still be seen represents the energy left. The speed with which it is moved into the box depends on the energy consumption of the device it is used with. When the briquet’s capacity is depleted, it falls out of the other side of the box and has to be reinserted into the box by the user to continue using the device.
consumption and the request to detect and avoid power guzzlers. We saw a clear indication here that there is indeed a need for solutions that allow users to display and compare the specific energy consumption of different electronic devices. All but one respondents recognized that these methods amplify the energy consumption awareness. Discussing the proposed system made it clear in all but one case that the respondents felt that the repeated deliberate gesture with the E-Briquet to run the electronic device and create awareness of energy consumption is an understandable method. Important to note here is that all but two of the respondents reconstructed and understood the charcoal briquet as the physical model. Two respondents further mentioned that due to the charcoal briquet metaphor, charcoal as still predominant and environmentally unfriendly power source becomes even more aware. Almost all respondents liked the interaction with the system especially the handling with the E-Briquet. Compared to usual energy meters with just a number display they mentioned the concrete energy experience and the very tangible handling as decided advantages. It was also positively commented that the repeated deliberate gesture in combination with the dynamic and visualized consume activate awareness that energy is not abundantly available.
USER STUDY
In order to find out whether a necessity exists for such a tangible energy meter we took our prototype to the university mensa. We approached 10 people (3 female, 7 male), including students (with care taken to avoid students from our own department), staff and visitors. Our goal was to assess how such a system could contribute to the conservation of energy. Interviews and question papers were conducted, whilst demonstrating the prototype and allowing the probands to interact freely with the device. Main topics in the discussion were the general power saving behavior, thoughts and comments about the suggested device, the understandability of the charcoal briquet metaphor and the interaction and recurring gesture with the device. RESULTS
Of our probands, all but one are interested to get aware about the specific energy consumption of different electronic devices. The most cited reasons were the desire for a more transparent and comprehensible electricity
Figure 2: The E-Briquet with the LED-display
As far as the appearance (shape, color, material) of the prototype is concerned, the testers were undecided. Some respondents would have preferred a greater similarity to a real briquet to reinforce the metaphor (e.g.: a black briquet with patina or a materiality change between unconsumed
consuming or consuming a lot of power or even both, so that the E-Briquet has to be reused several times for the activity, could provide useful results for further work. RELATED WORK
In the preface of the concept phase, we conducted research in the field of energy-meters with the option to compare the specific energy consumption of electronic devices. Also actions and gestures with energy-meters were looked into. The possibility to create an awareness for energy consumption was investigated.
The results of our user study have shown that there is a desire for gaining more control and knowledge about the energy consumption of their devices and that many considered it especially important to identify major power consumers. Almost all of the respondents understood our underlying concept of using the charcoal briquet metaphor and the deliberate gesture to refeed the E-Briquet into the system. The whole tangible interaction process was seen as promising by the majority of the probands because it leads to a better experience of the fact that energy is limited as they said. That said, we have the feeling that tangible interaction could indeed be a good way to help people grasp energy consumption in their household. Regarding the appearance of the E-Briquet there seems to be room for discussion. The clean white design might not be the most appropriate solution. Also, we have to think of reducing the size of the system especially when you imagine having many systems for several electronic devices. We should also take account of the fact that some respondents proposed such a system only for the devices that you are actually interested in in terms of consumption. Lastly it has to be taken care of that the system itself is no substantial power consumer and uses as little energy as possible.
Related to our idea to display and compare the specific energy consumption of different electronic devices is the Kill-A-Watt (KAW) [4], a commercial product manufactured by P3 International. The Kill-A-Watt allows to measure the power being used by a specific device being plugged into a wall socket. By plugging it in the Kill-AWatt outlet the meter measures how much power it is consuming by the kWh and displays it over a LCD display. Through this the Kill-A-Watt is able to make aware which device drives up the power bill and motivates to use these devices more attentively. Also well known is the PowerAware Cord [5]. It is a power strip that visualizes the amount of electricity that flows through the connected devices. The entire cord acts as an ambient display, where the current use of electricity is represented through the frequency of glowing pulses. Both products use a kind of display to visualize the energy consumption. However apart from plugging the electronic device into the wall socket there are no further gestures or actions needed. In our energy-meter concept we tried to combine a display with a tangible gesture to make energy consumption more conscious. A related project, in which more emphasis is put on tangibility and gestures is the Energy Lock concept of Designer: Young Suk Kim [6]. Energy Lock is a featurerich power socket. It acts as an on/off switch and a timer. To switch on the device, it has to be turned ninety degree clockwise. For the timer, the power socket has to be turned less than ninety degree and it will translate to a certain amount of time, which will countdown. If time is expired, the socket will be back in its original position, and the plugged in electronic device will be turned off.Compared to our concept, the Energy Lock also uses a deliberate gesture, repeated each time the electronic equipment is operated, to make users aware of his/ her energy usage. However, the frequency of the gesture is based on time, not on actual energy consumption. Furthermore the gesture of our concept has little symbolic meaning. We tried to build on an ancient usage of energy and use that image in a modern setting.
FUTURE WORK
ACKNOWLEDGEMENTS
Figure 3: Inside of the box
and the consumed E-Briquet ). Others preferred the current look because of the simple, discreet and clear design. Further suggestions for improvement referred to a technical more optimal execution of the prototype. Three respondents mentioned a smaller and less conspicuous extent of the prototype. Two of the respondents advised as little as possible or no electronic drive for it. CONCLUSION
To be able to fully assess the effect of our system on the energy awareness of users and their ability to conserve energy, an experiment with a control group and a test group should be conducted. Picking an activity for the experiment with a device that is either usually particularly time-
We would like to thank [obfuscated] and [obfuscated] for their help and assistance during this project.
REFERENCES
1.Forsa (Gesellschaft für Sozialforschung und statistische Analysen mbH) Study, Erfolgsfaktoren von Smart Metering aus Verbrauchersicht. http://www.vzbv.de/mediapics/smart_metering_studie_05 _2010.pdf. 2.GreenDex. Consumer Choice and the Environment – A Worldwide Tracking Survey http://environment.nationalgeographic.com/environment/ greendex/ 3.Smart Meters Alone Won’t Reduce Energy Use, Study Says
http://www.greenbiz.com/news/2010/07/01/smart-metersalone-wont-reduce-energy-use-study-says 4.P3 International – Kill-A-Watt. 2010. http://www.p3international.com/products/special/P4400/P 4400-CE.html 5.Gustafsson, A. and Gyllenswärd, M. The power-aware cord: energy awareness through ambient information display. CHI'05 (2005), 1426. 6.Yanko Design: Energy Lock. 2010. http://www.yankodesign.com/2010/03/31/a-morepowerful-lock/