ME 4343 HVAC Design Lecture 1 -- Introduction

The Impact of Occupancy Behavior Patterns On the Energy Consumption in Low-income Residential Buildings

Bing Dong1, Yifei Duan1, Rui Liu2, Taeg Nishimoto2

1 Building Performance and Diagnostics Group, Mechanical Engineering, the University of Texas, San Antonio, TX, USA2 College of Architecture, the University of Texas, San Antonio, TX, USA

ME 4343 HVAC Design1IntroductionLarge gaps between measured performance and simulated results

Source: NBI report 2008 Energy Performance of LEED For New Construction Buildings

2IntroductionOccupancy behavior (OB) has significant influence on building energy use

3IntroductionPeople spend most of time at homes

Based on American time user survey data (ATUS) 4IntroductionOccupancy behavior is a key factor influencing building energy consumption and indoor environmentClimateConditionBuilding EnvelopeBuilding SystemsBuildingOccupancyBehaviorOccupancyPresenceOccupancyActivitiesOccupancyOperationEnergyConsumption5UTSA Occupancy Test-bedsThree+1 project for Westside low income housesA collaborative project of UTSA the San Antonio Alternative Housing Corporation, and the Texas Department of Housing and Community AffairsHonorable Mention for Research and Education in Residential Construction, presented by City of San Antonio Green Building Awards, 2013

6Introduction

SIPs House 1,073sf

AAC House 1,019sf

Container House1,106sf

Stick House 1,000sf

. 7Instrumentation

Powerhouse Dynamics e-Monitor

Temperature Sensor Nonintrusive Sensor Network8Energy ConsumptionTotal Monthly Energy Consumption# of Occupants at homes2244

3 StickEven with best material as SIP house, the energy consumption rises high.

How many people in different houses?Does number of people matters ? No. In this case, the number of people did not impact on the energy consumption 9Behavior 1: Thermostat Schedule

All four houses thermostat scheduleAugust 12 to August 19, 2013

DOE BenchmarkBehavior 1: Thermostat Schedule HVAC working status for 1 week

OnSIP houseAAC house OffBehavior 1: Thermostat Schedule

Energy Consumption of HVAC for 1 week(12/8-19/8)Energy Consumption (kWh)Behavior 2: Usage of Major AppliancesEnergy Consumption of Stick House for 5 months

Building Energy Data Book (2009)

Cooling and Heating45%Behavior 2: Usage of Major Appliances (Water Heater)

Energy Consumption of Water Heater for 1 week(12/8-19/8)Energy Consumption (kWh)Behavior 2: Usage of Major Appliances (Water Heater)SIPStickATUSBehavior 3: Occupancy Movement

Occupancy movement in SIP houseTemperature Profiles of living room and master bedroom of SIP house

Living Room16Behavior 3: Occupancy Movement

Living Room in SIP house(aggregated one week data)High ProbabilityFor example, between 7pm to 9pm 17Behavior 3: Occupancy Movement

Kitchen in SIP house(aggregated one week data)

Integrate with Energy Models

Occupancy Movement PatternsNew Thermostat ScheduleBuilding Controls Virtual Test bed (LBNL)

Measured Energy and Temperature DataEnergy Saving: 15%Comfort time Increase: 25%

Appliances Conclusion and Future Work In this study, we present occupancy behavior and energy usage patterns in four low income housesWe also demonstrate possible energy savings based on occupancy movement

In future studies, we will: Develop statistical models to describe occupancy behavior in buildings. Integrate with energy consumption patternsIEA Annex 66IEA Annex 66 Definition and Simulation of Occupant Behavior in Buildings.

23 countries and regionsUTSA BPD group is task leader of subtask 1.

21Acknowledgement