AC-02-12-4 -- Monitoring HVAC Equipment Electrical Loads from a Centralized Location—Methods and Field Test Results

This paper reports recent work to determine useful information about component-level HVAC electrical loads—not from submeters, which are accurate, rarely installed, and relatively expensive, but instead from one or more centralized locations in a building's electrical distribution system. The work includes laboratory tests with real-building data and field tests made with low-cost hardware capable of the rapid sampling needed for load disaggregation. Results indicate that building electrical signals are often quite complex, that individual loads can indeed be detected with reasonable reliability, that more work is required to automate the process of tuning the detection algorithm, and that there are benefits to analyzing turn-on/turn-off events at multiple sampling rates to minimize trade-offs between detection sensitivity and false alarms.