Design Implications for the Presentation of Eco-feedback Data

Background : Four decades of eco-feedback studies have produced promising energy conservation results. Up-to-date smart electricity meters allow eco-feedback strategies such as real-time monitoring with appliance-specific data, social comparison, multiple metrics (e.g., cost, CO₂, trees), and personalized feedback. Unfortunately, eco-feedback presentation methods for such strategies have been under-studied. Methods : We have investigated the design of energy chart components (i.e., chart type, time range, time intervals), and supportive eco-feedback information (i.e., metrics, personalized advice). Each component was evaluated by measuring the performance of thirty-five participants (e.g., response time and correctness) and their preferences (e.g., understandability and attractiveness). Result : Whereas most of the energy-monitoring applications show the current day’s energy usage information, it is found that users preferred to see the current week’s energy usage with hourly intervals because this better reveals opportunities for saving energy. Users also preferred a stacked area chart over a stacked bar chart to view the disaggregated individual’s data, and a line chart over a bar chart for social comparison data. The environmental metrics (i.e., CO₂ and tree) confused the users, but cost ($) and KWh were preferred. Conclusions : This study investigates the eco-feedback presentation methods based on survey measures. The next step in this research is to quantify the amount of energy saved using these methods.