SDB Demand-Controlled Ventilation: Preliminary Experiments Demand-Controlled Ventilation: Preliminary Experiments Jay Taneja Software Defined Buildings Kickoff January 11 th , 2013
Feb 23, 2016
SDB
Demand-Controlled Ventilation: Preliminary
Experiments
Demand-Controlled Ventilation: Preliminary
ExperimentsJay Taneja
Software Defined Buildings KickoffJanuary 11th, 2013
SDB 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
SDB DCV: Standards and Sensors
• ASHRAE 62.1 and CA Title 24
• CO2 sensors
• Works best in enclosed spaces
• Target max of 800 ppm CO2
SDB Baseline Ventilation
SDB 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
SDB Extreme Efficiency Ventilation
SDB 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
SDB Demand-Controlled Ventilation
SDB Results
Ventilation Strategy Avg. Airflow Avg. Ventilation Power
Time > 800 ppm
Baseline 222.2 cfm 0.1765 kW 6h 3m (3.6%)
Extreme Efficiency 79.8 cfm 0.0616 kW 10h 57m (6.5%)
DCV 40.2 cfm 0.0272 kW 17m (0.2%)
• 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.
SDB 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
SDB Questions?
Jay Taneja<[email protected]>