Demand-Controlled Ventilation: Preliminary Experiments

1. Demand-Controlled Ventilation: Preliminary Experiments Demand-Controlled Ventilation: Preliminary Experiments Jay Taneja Software Defined Buildings Kickoff January 11th, 2013

2. Motivation • SDBs can improve comfort • Indoor environmental quality is multifaceted • Buildings are often overventilated • Demand-controlled ventilation (DCV) • DCV benefits from BOSS Architecture • Incorporates non-BMS sensors and data • Transactions ensure safe system state • Communication throughout buildings

3. DCV: Standards and Sensors • ASHRAE 62.1 and CA Title 24 • CO2 sensors • Works best in enclosed spaces • Target max of 800 ppm CO2

4. Baseline Ventilation

5. Extreme Efficiency Description • Preliminary control effort to limit ventilation as much as possible • Combines an occupancy model, outside air damper control sequence, and significant reductions in default airflow levels

6. Extreme Efficiency Ventilation

7. DCV Description • Incorporate Google Calendar data • Proportional control (airflow reflects CO2) • Prior to meetings: Increase airflow • During meetings: Modulate minimum to reflect CO2 concentration • Not during meetings: Only respond if CO2 approaches 800 ppm threshold

8. Demand-Controlled Ventilation

9. Results • Caveats • Not all weeks created equal • Could increase airflow to reduce violations DCV offers a combination of energy savings and increased occupant comfort at minimal cost.

10. Next Steps • Expansion in SDH • 7/12 rooms with calendar data have sensors • DCF in cleanroom using motion sensors • Grid potential as a supply-following load • Minimal ability to shed (positive slack) • Substantial ability to sink (negative slack) • Incorporate MPC for balancing objectives • Integrate with BAS – write once, run anywhere

11. Questions? Jay Taneja <taneja@cs.berkeley.edu>