Energy Efficient Residential Thermal Control With Wireless Sensor Networks: A Case Study for Air Conditioning in California

Residential thermostats are sensor-limited devices, but low-cost wireless sensor network technology is enabling new spatially distributed sensing capabilities. This paper evaluates the energy and comfort performance of three multi-sensor control strategies that use wireless temperature and humidity sensors in each room and that can be applied to existing on-off residential central systems. The multi-sensor control strategies adjust the temperature set point of a thermostat to control the average of all room temperatures using a temperature threshold logic, minimize aggregate discomfort of all rooms, or maximize the number of rooms within a comfort zone. The strategies were tested using a custom wireless sensor network control system in a seven room, 2,100 square foot single-story house located in Pleasanton, CA during August and September. Performance was benchmarked against an implementation of a single-sensor constant temperature set point control logic using the custom control system and against a constant temperature set point using the original thermostat. Results show multi-sensor strategies may produce simultaneous improvements in energy consumption, room-to-room temperature distributions, and average comfort, compared to the single-sensor constant temperature set point threshold logic.Copyright © 2008 by ASME