Presentation on theme: "RoomZoner: Occupancy-based Room-Level Zoning of a Centralized HVAC System Tamim Sookoor and Kamin Whitehouse April 11, 2013 4 th International Conference."— Presentation transcript:
Zoning With a Central HVAC System 8 Central HVAC One sensor One heater/cooler Zoned HVAC N sensors N heaters/coolers RoomZoner N sensors One heater/cooler N + 1 control signals Can a central HVAC system safely be used for zoning? Can it be implemented with COTS components?
Conservative Temperature Averaging 20 65 °F 69 °F 70 °F 72 °F 77 °F 74 °F 78 °F Heating: Max Cooling: Min Trade-off comfort for stability
Occupancy Characterization Analyze Historical Occupancy Data – Find sensor firing frequencies that identify Stable occupancy – Start of long-term usage – End of long-term usage Transitional occupancy – Start of temporary usage – End of temporary usage 21
Occupancy Characterization Exhaustive search over frequencies – Minimize total occupancy time 22 Maximum False Negatives Maximum State Transitions Maximum 25 th Percentile Duration (mins) Stable304 Transitional4303 Sensor frequencies
Limitations and Future Work Current system built using an ad-hoc approach – Use a control-theoretic approach such as MPC Current evaluation limited in scope – Evaluate system in multiple houses – Extend evaluation period 27
Conclusions Centralized HVACs can be retrofitted for zoning – Low-cost DIY installation – Saves energy Requires incorporation of prediction – Predict room-level occupancy (POEM?) – Predict room temperature changes (Matchstick?) One step towards residential room-level zoning of centralized HVAC systems 28