Wireless Sensors and Controls for Building Applications

Wireless Sensors and Controls Wireless Sensors and Controls for Building Applicationsfor Building Applications

Improving the Actual Operating Efficiency of Commercial Buildings

Michael Kintner-Meyer, Ph.D.

June 17, 2004

Sponsored by U.S. DOE, Office of Energy Efficiency and Renewable Energy (EERE), Building Technologies Program, David Hansen, Program Manager

Email: Michael.Kintner-Meyer@pnl.gov, Phone: 509.375.4306

210/29/2004

OutlineOutlineOutline

Why wirelessWhat is the opportunity for building operationOverview of wireless sensorsDemonstration projects at PNNLTrends

310/29/2004

Why Wireless?Why Wireless?Why Wireless?You can’t control and maintain what you don’t measure and monitorSensing is the foundation for good operation, control and maintenance—it’s an enabling technology—but it’s too expensive ($200 to >$1000 per point)Wiring represents 20% to 80% of a sensor point in commercial buildingsCost savings: substitute technology for labor for installation and servicingMore sensors will enable performance monitoring, automated diagnostics, automated real-time commissioning higher performance systems

410/29/2004

Time versus CostTime versus CostTime versus Cost

Proportions of time devoted to facility management tasks

Fractions of annual purchases by facilities globally

Maintenance and Operations

Project Management & AdministrationMeetings

Training

Utilities

Electrical

Asset Management

Space Planning

Purchases

Outsourcing

Engineering

Reliability

Reporting

Policies and proceduresPlanning and

forecasting Staffing

Safety

Maintenance and Operations

Project Management & AdministrationMeetings

Training

Utilities

Electrical

Asset Management

Space Planning

Purchases

Outsourcing

Engineering

Reliability

Reporting

Policies and proceduresPlanning and

forecasting Staffing

Safety

5-6%

Repair & Maintance20%

Cleaning19%

Utilities34%

Security3%

Roads/Grounds8%

Administrative16%

Source: NorthWrite Inc. unpublished survey, 2002 Source: 1998 BOMA Experience Exchange Report 2002

510/29/2004

Opportunities of Wireless Sensors and Controls for Building Applications

Opportunities of Wireless Sensors and Opportunities of Wireless Sensors and Controls for Building ApplicationsControls for Building Applications

Key driver: low-cost will enable ubiquitous sensingOperational benefits

Thermal comfort improvement (high-spatial resolution sensing)Extended life-time (conditioned-based maintenance)Energy efficiency (trouble-shooting)Demand responsiveness, load managementInventory control by RFID tagsSafety and security improvement

610/29/2004

Components of a Wireless SensorOne-directional

Components of a Wireless SensorComponents of a Wireless SensorOneOne--directionaldirectional

710/29/2004

Components of a Wireless SensorTwo-directional

Components of a Wireless SensorComponents of a Wireless SensorTwoTwo--directionaldirectional

Reader

810/29/2004

Overview of Wireless SensorsOverview of Wireless SensorsOverview of Wireless SensorsDifferentiation of wireless sensor technology

One-way vs. two-wayCommunication frequency (ISM)Spread spectrum vs. single frequencyCommunication protocolNetwork topologyBattery operated versus line poweredIntegration

Stand-aloneWeb-enabledIntegration to existing wired controls networks

910/29/2004

Wireless Devices and Communication Protocols

Wireless Devices and Communication Wireless Devices and Communication ProtocolsProtocols

Short Range

Mobile network

100 1k 10k 100k 1M 10M 100M

10mW

0.1W

1W

10W

100W

1mW

[bits/s]

Pow

er c

onsu

mpt

ion

ISMZigbee

GSMGPRS

3G

Bluetooth

802.11b802.15.3

802.11a

LAN

Line

pow

ered

Bat

terie

s re

gula

rly c

harg

edLo

ng-te

rm b

atte

rypo

wer

ed

1010/29/2004

Network TopologyNetwork TopologyNetwork Topology

Mesh networkStar with Repeater

networkStar networkPoint to Point

Sensor node

Repeater node

Gateway node

PC or LAN

1110/29/2004

PNNL Demonstration ProjectsPNNL Demonstration ProjectsPNNL Demonstration Projects

Started in 20023 buildings

2 applications inside office buildings1 application with rooftop HVAC equipment

Analyze cost-effectiveness of wireless sensors in large office buildings

Analyze installation effortsTest robustness of communicationsAnalyze maintenance requirementsCompare cost (wireless vs. wired systems)Lessons learned

What are the issues in set-up and maintenance of wirelessOther considerations

1210/29/2004

Building 1Building 1Building 1

• about 70,000 sq. ft. office space• steel-concrete construction• 3 floors• Built-up HVAC system

•Federally owned•Operated by Battelle

1310/29/2004

Wireless Network TopologyBuilding 1

Wireless Network TopologyWireless Network TopologyBuilding 1Building 1

N2 bus Receiver/Translator

TTT

T T

T

T T

TT

Repeater

Mechanical Room

Wireless Network• 32 temperature transmitters• 3 repeaters• 1 receiver/translator

T

T

1410/29/2004

Wireless Sensor Network Technology

Battery-powered Temperature sensor and

transmitters

Receiver Repeater TranslatorFrom wireless to

N2 bus

BAS

- Line powered- Range: 4 miles

- Up to 100 transmitters

- 900 MHz - FHSS- Range: 2500 ft. - Battery life: 3 y- Sensor: RTD

1510/29/2004

Building 2 Building 2 Building 2

45,000 sq.ft.2 FloorsCentral open space170 offices on two corridorsWalls

Metal studsGypsum wall board

Ceiling:Metal sheetingConcrete floor

1610/29/2004

Wireless Sensor NetworkBuilding 2

Wireless Sensor NetworkWireless Sensor NetworkBuilding 2Building 2

Labo

rato

ry

Off

ice

89’

80’

N2

Bus

integrator

receiver

office

Labo

rato

ry

Off

ice

Labo

rato

ry

Off

ice

89’

80’

N2

Bus

integrator

receiver

89’

80’

N2

Bus

integrator

receiver

office

40 wireless temperature sensors distributed in one wing

Total of 120 wireless temperaturesensors in building

1710/29/2004

Cost of Wireless InstallationCost of Wireless InstallationCost of Wireless Installation

WIRELESS: wireless system for 32 nodes

About $134/sensor for wirelessInstalled cost: $4300Recurring cost of replacement of batteries (3-5 years) not included

WIRED:$220/sensor, including temperature sensors

WIRELESS: wireless system for 120 nodes

About $78/sensor for wirelessInstalled cost: $9400Recurring cost of replacement of batteries (3-5 years) not included

WIRED:?

Building 1 Building 2

1810/29/2004

Lessons Learned, Building 1Lessons Learned, Building 1Lessons Learned, Building 1Implementation

32 wireless temperature sensors3 repeaters1 receiver, 1 translatorIntegrated into JCI Metasys

BenefitsControl:

Chilled water reset strategy based on averaged zone temperatures$6000 cost savings per year payback <1 year.

TroubleshootingIdentification of cold spots in zones led to reset of the entire building temperature, thus avoiding overcooling and use of space heatersSignificantly improved thermal comfort (hot/cold calls down)Heat buildup in kitchen

ObservationsWireless networks work very reliably, since Spring 2002Facility staff fully embraced wireless technology as enabling technology

Suggested additional applications- Monitoring emergency lighting ballasts- Occupancy sensing

Communication to occupants was necessary to explain new technology

1910/29/2004

Lessons Learned Building 2Lessons Learned Building 2Lessons Learned Building 2Implementation

120 wireless temperature sensors in individual officesno repeaters3 receiver, 3 translatorIntegrated into JCI Metasys

BenefitsControl:

Shut off ventilation system after 6p.m. as long as ALL offices maintain 55F<T<78FObservations

Wireless networks work very reliably, since Summer 2003Facility staff fully embraced wireless technology as enabling technologySuggested additional applications

Monitoring critical laboratory experimentsOccupancy sensing

ConsiderationsVulnerability clearance for wireless systemTheft

2010/29/2004

HVAC#6

HVAC#5

HVAC#4

HVAC#3

HVAC#1

HVAC#2

Concentratorfor wireless -

HVAC

ABCIndustries

Rooftop ApplicationRooftop ApplicationRooftop Application

2110/29/2004

System Types TestedSystem Types TestedSystem Types TestedSystem configured from generic components – applied to one unit

2210/29/2004

System Types TestedSystem Types TestedSystem Types TestedSystem specifically manufactured for package unit monitoring – applied to 4 units

2310/29/2004

Converting Data Into InformationFault Detection and DiagnosticsConverting Data Into InformationConverting Data Into InformationFault Detection and DiagnosticsFault Detection and Diagnostics

Test BuildingTest Building

2410/29/2004

Cost CompetitivenessCost CompetitivenessCost Competitiveness

Cost

Sensors

Wiring

Communication and signal-conditioning hardware

Labor

Total cost

Average cost per sensor

Cost Component

Monitoring System for Three Packaged HVAC Units

WiredDesign

Wireless Design

$636 $636

$68[1] ---

$1903 $1500

$1179[2] $450

$3786 $1950

$316 $163

[1] Including conduit.[2] Including installation of conduit.

2510/29/2004

Interim Findings and Conclusions For Rooftop Application

Interim Findings and Conclusions For Interim Findings and Conclusions For Rooftop ApplicationRooftop Application

Initial problems with reliability of hardware (most have been overcome)Technical challenge:

Right combination of components that provides adequate accuracy, reliability, persistence, and cost

Several units can be monitored using one wireless RF receiverWireless costs per sensed point decrease as the number of units monitored by a receiver increases

2610/29/2004

Summary of Demonstration ProjectsSummary of Demonstration ProjectsSummary of Demonstration Projects

In 2001, there was no commercial wireless product for building application availableFor in-building application, products worked wellFor rooftop application, the right product yet to be producedWireless sensors are cost competitive today in retrofit applicationsWireless technology particularly attractive

FlexibilityExpandability with incremental cost for adding one sensor

2710/29/2004

TrendsTrendsTrendsIndustry is in early stages of technology/product developmentIndustry is dynamic and fluid dominated, by small companiesKey market driver: Huge market size of wireless sensors (several orders of magnitude larger than expected IP nodes) Building automation is one of many target markets. Others are

Home automationAMRIndustrial process controlAutomotiveMedical monitoringAsset tracking

“OnWorld” projects sales of wireless sensors (all sectors)6 million (2004)465 million (2010)Significant cost reduction ( no one knows how low prices for end-user will go)

Self-powered devicesExpected to be a glut of data coming from thousands of sensors. This will drive new applicationsOpportunities for building application

End-use power monitoringComfort (thermal, IAQ, lighting) monitoringEquipment monitoring