Bing Dong1, Yifei Duan1, Rui Liu2, Taeg Nishimoto2 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, USA 2 College of Architecture, the University of Texas, San Antonio, TX, USA

Introduction Large gaps between measured performance and simulated results Source: NBI report 2008 Energy Performance of LEED For New Construction Buildings

Introduction Occupancy behavior (OB) has significant influence on building energy use

Introduction People spend most of time at homes Based on American time user survey data (ATUS)

Introduction Building Occupancy Behavior Occupancy behavior is a key factor influencing building energy consumption and indoor environment Climate Condition Building Energy Consumption Building Envelope Occupancy Behavior Building Systems Occupancy Presence Occupancy Activities Occupancy Operation

UTSA Occupancy Test-beds “Three+1” project for Westside low income houses A collaborative project of UTSA the San Antonio Alternative Housing Corporation, and the Texas Department of Housing and Community Affairs Honorable Mention for Research and Education in Residential Construction, presented by City of San Antonio Green Building Awards, 2013

Introduction AAC House Container House . SIPs House Stick House 1,019sf Container House 1,106sf . SIPs House 1,073sf Stick House 1,000sf

Instrumentation Nonintrusive Sensor Network Temperature Sensor Powerhouse Dynamics e-Monitor

Energy Consumption Total Monthly Energy Consumption # of Occupants Even 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 Stick # of Occupants at homes 2 4 4 2 3

Behavior 1: Thermostat Schedule DOE Benchmark August 12 to August 19, 2013 All four houses thermostat schedule

Behavior 1: Thermostat Schedule HVAC working status for 1 week SIP house AAC house On Off

Behavior 1: Thermostat Schedule Energy Consumption of HVAC for 1 week(12/8-19/8) Energy Consumption (kWh)

Behavior 2: Usage of Major Appliances Cooling and Heating 45% Energy Consumption of Stick House for 5 months Building Energy Data Book (2009)

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) SIP Stick ATUS

Behavior 3: Occupancy Movement Occupancy movement in SIP house Living Room Temperature Profiles of living room and master bedroom of SIP house

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

Behavior 3: Occupancy Movement Kitchen in SIP house (aggregated one week data)

Integrate with Energy Models Appliances Energy Saving: 15% Comfort time Increase: 25% New Thermostat Schedule Occupancy Movement Patterns Building Controls Virtual Test bed (LBNL) Measured Energy and Temperature Data

Conclusion and Future Work In this study, we present occupancy behavior and energy usage patterns in four low income houses We 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 patterns

IEA Annex 66 IEA Annex 66 “Definition and Simulation of Occupant Behavior in Buildings”. UTSA BPD group is task leader of subtask 1. 23 countries and regions

Acknowledgement