Building Energy Data Visualizations for Experts: A Usability Evaluation

The increasing volume and complexity of building energy performance data require effective visualization tools to support expert analysis and decision-making. This study evaluates the usability and cognitive effectiveness of a prototype tool designed for building energy professionals, integrating visualizations such as stacked bar charts, heatmaps, line charts, radar charts, and scatter plots. The tool’s design was informed by collaboration between energy and programming experts to enhance functionality and user engagement. A structured usability study was conducted with building physics and energy efficiency professionals, who completed task-based evaluations reflecting real-world interactions with energy data. Usability was assessed through both objective and subjective measures, including task efficiency, user satisfaction, and cognitive load, collected via questionnaires, interviews, and task analysis. Results indicate that line charts and heatmaps enable rapid, accurate interpretation, whereas radar charts present usability challenges due to their complexity. Beyond identifying visualization preferences, this study establishes a detailed usability testing methodology for expert-user evaluation, proposes design improvements, and suggests interactive features to enhance decision-making processes. These insights inform the development of more intuitive, expert-centered visualization tools and offer guidelines for future usability research in energy data analysis.