Evaluating Energy-Efficiency using Thermal Imaging

Energy-efficiency remains a critical design consideration for mobile and wearable systems, particularly those operating continuous sensing. Energy footprint of these systems has traditionally been measured using hardware power monitors (such as Monsoon power meter) which tend to provide the most accurate and holistic view of instantaneous power use. Unfortunately applicability of this approach is diminishing due to lack of detachable batteries in modern devices. In this paper, we propose an innovative and novel approach for assessing energy footprint of mobile and wearable systems using thermal imaging. In our approach, an off-the-shelf thermal camera is used to monitor thermal radiation of a device while it is operating an application. We develop the general theory of thermal energy-efficiency, and demonstrate its feasibility through experimental benchmarks where we compare energy estimates obtained through thermal imaging against a hardware power monitor.