Farrokh Jazizadeh, Laura Klein, Geoffrey Kavulya, Burcin Becerik-Gerber

Department of Civil and Environmental Engineering

University of Southern California

US Building Energy Consumption

83% of energy comes from fossil fuel sources

Buildings account for 40% of national energy consumption

Heating/cooling accounts for 29% and lighting accounts for 27% of

building energy consumption

Continuous efforts have been made to reduce building energy

consumption and CO2 emissions.

Building systems performance should optimize both energy consumption

and occupant satisfaction.

ICampus IWatch CT

Energy Consumption vs. Occupant Satisfaction

Occupant satisfaction is influenced by indoor ambient factors such as

temperature, lighting and air quality, and measured by:

• Thermal comfort

• Visual comfort

• Indoor airflow and air quality

Predicted Mean Vote (PMV) index for thermal comfort depends on:

• Temperature of the room

• Relative humidity

• Air velocity

• Mean radiant temperature

• Users activity level

• Clothing level

• Metabolic rate

Current regulation of acceptable ranges of ambient factors includes:

Previous and current research motivations to improve industry standards:

Could be obtained by sensors

Difficult to be obtained by sensors;

usually based on predefined values

for particular situation

One time or periodic occupant surveys or complaints

Industry standard set points

Weak and context-dependent correlations between code-

defined and occupant reported comfort ranges

Potential for reduced building energy consumption by adaptive

systems control

Need for improved methods for continuous data collection of

occupant satisfaction

Unvverified assumptions about building occupancy and

occupant behaviors

Current research approach: Participatory Sensing and

Occupant Energy Literacy

System Architecture

Building

Management

System (BMS)

Controlling

modules

Building Systems

Standards

Improvement

Statistical

Analysis

Energy Literacy

and Occupants

Contribution to

Green

Environment

iCampus

Platform

Visualization

Application Design

Real-time occupant perceptions of the indoor

environment

Questions designed to encourage fast and frequent

input

Spatiotemporal perceived factors:

• Temperature

• Lighting level

• Airflow

Questions designed based on industry standard

sensation scale (ASHRAE).

GPS based locating algorithm provides the participant

with three nearest buildings to their current location Application for Android

Different versions developed

for Android and iPhone

Visualization

Participatory data is mapped on building

floor plans in 3D visualization environment

Participants view mean values of ambient

factor perceptions and changes over time

Electricity consumption data is mapped on

buildings and historical trends are

visualized around the campus

Visualization features increase participation

and improve participant energy literacy

Energy consumption visualization

Application Verification &

Implementation

8 rooms on 3 floors of a university building

Perceived temperatures were compared to

actual temperature data

65% of the data points for perceived

temperatures differed from neutral condition

Future verification in a test bed building,

equipped with various sensors for ambient

factors

Eventual implementation in the entire USC

campus

Commercial Energy Use, Source: Energy Data Book (2007); EERE, U.S. Department of Energy

Participatory Input Building Design Occupant Feedback Building Operations

Ambient factors mapped on building floor plan

Participatory sensing: using mobile devices, especially smart

phones, to utilize human intelligence for sensing and provide the

optimal context-aware and large-scale data collection approach.