Abstract: A system and process for control of energy use in a rented room based on direct occupancy observation. The system is designed to control up to 100% of the power usage. The system includes: a power supply; occupancy sensors; a thermostat responsive to a predetermined signal; electrical outlet receptacles and/or switches that are responsive to a predetermined signal transmitted over the powerline; and a central interface unit for receiving signals from the occupancy sensors and, based on the signals received from the occupancy sensors, controlling power consumption by the thermostat and electrical outlet receptacle and/or switches. The system can be used in a process for improving energy efficiency by direct observation of occupancy of an area in multitennant facilities, such as hotels, that has a plurality of discrete living quarters.