Shwetak Patel is a computer scientist who has invented a series of sensor technology systems for home environments with the goal of saving energy and improving daily life through a broad range of applications. Much of his work to date has focused on the development of low-cost and easy-to-deploy devices that can detect and measure household energy consumption without an elaborate network of expensive instruments. To allow residents to track their energy usage down to the level of individual appliances and fixtures, Patel’s distinctive approach leverages existing infrastructure — such as gas lines, electrical wiring, plumbing, and ventilation ducts — and requires only a minimal number of small, wirelessly connected sensors attached to the central hookup of each of these utility sources. When coupled with a machine learning algorithm that analyzes patterns of activity and the signature noise produced by each appliance, the sensors enable users to measure and disaggregate their energy and water consumption and to detect inefficiencies more effectively. In addition to the resource conservation applications of his sensor systems, Patel is also exploring their potential for home security or elder care, as they serve the related function of sensing human activity and monitoring movement throughout a building’s rooms. While envisioning cutting-edge new tools to address pressing social challenges and to make the buildings we live in more responsive to our needs, Patel devises elegant, simple solutions that dramatically reduce the cost of implementation.