Energy is a precious resource and as electronic devices (e.g., tablets, smart phones, Internet-connected appliances) and electric cars become ubiquitous, the demand for energy will continue to increase. To meet this demand and enable the integration of renewable resources, electrical distribution networks are beginning to adopt smart-grid technologies by providing bidirectional communication between the distribution grid and the electric meter. The question of how appliances within the home will interface with the smart-grid is still an open question. We propose to use wireless sensor networks as a platform to enable detailed household monitoring, demand response, load scheduling, occupancy-based control, intelligent lighting, and other general-purpose control strategies. In this vision, the smart-grid interface is a single input to the building control system which consists of a wide variety of other sensors and supports many applications that greatly extend the capabilities of the smart-grid. To explore this concept we have: developed efficient and accurate energy disaggregation algorithms, developed reliable multicast and broadcast network protocols, evaluated 10 strategies for energy savings, designed a WSN-based building monitoring and control platform, and evaluated this approach in both offices and a residential home.