Although not collected specifically for energy disaggregation, the Smart* (Smart Star) data set provides power data from 3 thoroughly sub-metered real households. The granularity of data collected for circuit level monitors (premises aggregate and individual circuits) is one reading per second, while individual plug loads are measured roughly every few seconds. Each house contains 21-26 circuit meters and almost all appliances are measured using plug meters.
The data is available for download from the UMassTraceRepository. At the moment, aggregate, circuit and appliance data is available for house A, but only aggregate data is available for houses B and C. I've also updated my post on Public Data Sets for NIALM.
