The Design and Evaluation of an End-user-deployable, Whole House, Contactless Power Consumption Sensor

Shwetak Patel, Sidhant Gupta, Matthew S. Reynolds


We present the design, development, and evaluation of an end-user installable, whole house power consumption sensing system capable of gathering accurate real-time power use that does not require installing a current transformer around the electrical feeds in a home. Rather, our sensor system offers contactless operation by simply placing it on the outside of the breaker panel in a home. Although there are a number of existing commercial systems for gathering energy use in a home, almost none can easily and safely be installed by a homeowner (especially for homes in the U.S.). Our approach leverages advances in magnetoresistive materials and circuit design to allow contactless operation by reliably sensing the magnetic field induced by the 60 Hz current and a closed loop circuit allows us to precisely infer the power consumption in real-time. The contribution of this work is an enabling technology for researchers in the fields of Ubiquitous Computing and Human-Computer Interaction wanting to conduct practical large-scale deployments of end-user-deployable energy monitoring applications. We discuss the technical details, the iterative design, and end-user evaluations of our sensing approach.