In support of DOE’s sensors and controls research, the goal of this project is to move toward integrated building to grid systems by building on previous work to develop and demonstrate a set of load characterization measurement and evaluation tools that are envisioned to be part of a suite of applications for transactive efficient buildings, built upon data-driven load characterization and prediction models. This will include the ability to include occupancy data in the models, plus data collection and archival methods to include different types of occupancy data with existing networks and a taxonomy for naming these data within a Volttron agent platform. This research was conducted to: • determine desired characteristics of, and technical feasibility of, new sensors that can inexpensively monitor the number of building occupants; • explore how existing systems in buildings can be used to estimate the number of occupants as a function of time; and • use energy savings Measurement and Verification (M&V) methods to quantify changes in building energy performance, both with and without the use of occupancy data.