Download - 5 Building Sensors Healy
-
7/31/2019 5 Building Sensors Healy
1/33
William HealyNational Institute of Standards and Technology
Gaithersburg, MD USA
Building America Meeting on Diagnostic Measurement and Performance Feedback for Residential Space
Conditioning Equipment
April 26, 2010
-
7/31/2019 5 Building Sensors Healy
2/33
Sensors for Building ApplicationsCurrent StatusKey Challenges
Energy Monitoring Systems in Homes
-
7/31/2019 5 Building Sensors Healy
3/33
TYPICAL NEW CARS 40-50 sensors per car Wide range of types
Temperatures Pressure sensorsAccelerometers Oxygen Fluid level Proximity
TYPICAL BUILDINGS
Residential Thermostat Electric meter Gas meter
Water meter
Smoke sensors CO sensors Others embedded in equipment
Commercial (in addition tothose seen in residential apps)
RH Occupancy Light CO2
-
7/31/2019 5 Building Sensors Healy
4/33
Buildings do contain a large number of sensorsMany sensors in buildings are contained withinequipment and inaccessible outside that
equipmentPace of change much slower in types and
number of sensors included in buildingscompared to automobiles 30 years ago, typical automobile had 5 sensors Were the amount and types of sensors used 30 years ago
in buildings drastically different?
Bottom Line There are still many places where
improved sensing could be valuable in buildings
-
7/31/2019 5 Building Sensors Healy
5/33
From Wikipedia:Smart Systems typically consist of diversecomponents, such as:1. sensors for signal acquisition
2. elements transmitting the information to thecommand and control unit3. command and control units that makedecisions and give instructions based on theavailable information
4. components transmitting decisions and instructions 5. actuators that perform or trigger the required actions
-
7/31/2019 5 Building Sensors Healy
6/33
-
7/31/2019 5 Building Sensors Healy
7/33
A prerequisite to a smart buildingUbiquitous sensing could enhance smart
building operations by:
Sensing newphysical quantities
to improve
occupant comfort
and reduce energy
consumption
Providing finer
spatial resolution of
measurements
Enabling
monitoring of more
building equipment
-
7/31/2019 5 Building Sensors Healy
8/33
-
7/31/2019 5 Building Sensors Healy
9/33
Examples of types of sensors either neededor in need of improvements for buildingapplicationsLow-cost electric power meters
Low-cost and easy-to-install gas flow meters
Low-cost and easy-to-install water flow metersVentilation sensors (e.g., air flow rates)Indoor Air Quality sensors (e.g.,VOCs, particulates)Reliable occupancy sensorsLight sensors (e.g., intensity & color)Thermal comfort
-
7/31/2019 5 Building Sensors Healy
10/33
-
7/31/2019 5 Building Sensors Healy
11/33
Sensors must be easily installed in abuilding and must easily integrate into a
building monitoring and/or control
system
Easy, low-cost, and fast physical installationLittle expert knowledge required to activate
sensor
Little expert knowledge required to include andmake use of data in monitoring system
-
7/31/2019 5 Building Sensors Healy
12/33
WirelessEliminates wiring costsEliminates intrusion of wiringIncreases initial cost of equipment
On-board radio, antennaSoftware to manage wireless data transmissions on
board sensor node
Many commercial products have emerged overthe last 5 years.
-
7/31/2019 5 Building Sensors Healy
13/33
-
7/31/2019 5 Building Sensors Healy
14/33
MESH NETWORKS
Internet Model Multiple paths from sensor to
data collector
ExpandableAd-hoc networks can be self-
healing Disadvantages:
More complex software More data transmissions by
intermediate nodes leads toshorter battery life
STAR NETWORKS
Point-to-point communications Simpler system More predictable power
requirements Disadvantages:
Prone to disruption fromsingle points of failure
Limited range
-
7/31/2019 5 Building Sensors Healy
15/33
Application Key Design Issues Protocols
Telephones Quality of Service, Latency CDMA2000
Internet Bandwidth IEEE 802.11 (WiFi)
IEEE 802.16 (WiMAX)
Peripherals Bandwidth IEEE 802.15.1 (Bluetooth)
Wireless USB
Sensors Power IEEE 802.15.4 (ZigBee)
EnOcean
-
7/31/2019 5 Building Sensors Healy
16/33
Still need cost reductionsReliability concerns
Buildings present challenging environmentInterferenceMost hardware uses same open spectrum used by wireless
internet, cordless phones, and other consumer products
Power management
InteroperabilityEase-of-use and maintenanceSecurity
-
7/31/2019 5 Building Sensors Healy
17/33
-
7/31/2019 5 Building Sensors Healy
18/33
-
7/31/2019 5 Building Sensors Healy
19/33
IEEE 802.15.4 uses 2.4 GHz Industrial,Scientific, and Medical Band same as manyother protocols.
Other non-communication sources ofradiation in this band, e.g., microwaves
0.00%
2.00%
4.00%
6.00%
8.00%
10.00%
12.00%
14.00%
16.00%
0 2 4 6 8 10 12
Pa
cketErrorRate
Transmitter to Receiver Distance(m)
Control
WiFi
BlueTooth
Microwave
0.0%
1.0%
2.0%3.0%
4.0%
5.0%
6.0%
7.0%
8.0%
9.0%
10.0%
0 2 4 6 8 10 12
Pa
cketErrorRate
Transmitter to Receiver Distance (m)
Control
WiFi
BlueTooth
Microwave
Interference Source to Receiver Distance = 0.5 m Interference Source to Receiver Distance = 4 m
-
7/31/2019 5 Building Sensors Healy
20/33
Most networking schemes in place enable self-forming networksPlug-and-Play ? IEEE 1451 Standard for smart sensorsEach sensor maintains on-board identification informationStandard provides for multiple physical connections to
network, both wired and wirelessAutomatically announce its existence when connected to
network
Requires more hardware and softwareLingering Needs
Standard data models Holy Grailself-locating sensorsIt is feasible outdoors, but indoor installations present a wide
range of challenges
-
7/31/2019 5 Building Sensors Healy
21/33
-
7/31/2019 5 Building Sensors Healy
22/33
Self-Diagnosing
Self-Healing
Self-Calibrating
Self-Correcting
Low Battery AlertsGross Damage Alerts
Ad-hoc networks can
self-heal
Research phase
Research phase
Redundancy
provided bysensor
networks can
be utilized
-
7/31/2019 5 Building Sensors Healy
23/33
Battery power
Typical energy consumption of wireless sensors:
Typical shelf life of batteries ~ 5 yearsEnergy Harvesting
Photoelectric ThermoelectricVibrations
Radio mode Power consumption (mW)
Transmit 15
Receive 13
Idle 12Sleep 0.016
Lesson: Transmit
and Receive
messages as little as
possible
-
7/31/2019 5 Building Sensors Healy
24/33
-
7/31/2019 5 Building Sensors Healy
25/33
-
7/31/2019 5 Building Sensors Healy
26/33
World Business Council for
Sustainable Development:Technical devices to measure energy
consumption and provide immediate
feedback help to cut energy consumption
by as much as 20 %
U.N. Intergovernmental Panel on
Climate Change:Infrequent meter readings provide
insufficient feedback to consumers on their
energy use and on the potential impact of
their efficiency investments
-
7/31/2019 5 Building Sensors Healy
27/33
Parker et al. (2006) two year study of 22 homes in Florida Average change in energy usage of-7.4 %; significant variation (from -27.9 %
to +9.5 %)
Ontario Hydro One Study (2006) of over 400 homes
Average change in energy usage of-6.4 %
-
7/31/2019 5 Building Sensors Healy
28/33
Whole-house electricity monitoring
17 products identified in 2009
Most provide instantaneous power Some provide logging capabilities Range of installation procedures
Information Technology products for feedback 6 products identified in 2009 (probably undercounted) most were in development
Rely on other sources to provide dataPoint-of-use monitors
Five identified in 2009 Device inserted between outlet and end-use
-
7/31/2019 5 Building Sensors Healy
29/33
Sensor-richMany low-cost sensors monitoring end-usesData collection, analysis, and display at a central
point
Analysis-richFewer sensors (e.g., single sensor at main meter)Signal analysis to dissect end-usesNon-invasive load monitoringMIT work from the 1980s and 1990s
-
7/31/2019 5 Building Sensors Healy
30/33
From Hart (1992)
Reactive power may be needed
to differentiate end-uses
-
7/31/2019 5 Building Sensors Healy
31/33
Proliferation of new electronic devices has added more signatures to track
Variable speed motors do not havedistinct signature
CostCurrent commercial implementation costs ~$8k
But.it may have application for FDD
-
7/31/2019 5 Building Sensors Healy
32/33
Decreasing cost
Creating easy-to-install systemsWill not require professional plumber, electrician, orHVAC technician
Cannot require cutting into pipes
Should not require major electrical workSoftware setup should be straightforward
Improving methods to determine fossil fuelconsumption
Key Questions:How accurate must the measurements be?How can we minimize the number of sensing points
yet still provide adequate information for fault
detection?
-
7/31/2019 5 Building Sensors Healy
33/33
Key challenges related to sensor use inbuildingsDevelopment of new sensorsIntegration of sensors in a more straightforward
manner
Preservation of sensor performance with little humaninvolvement
Home Energy Monitoring SystemsMany systems have recently emerged
Many improvements are still neededEase of installation and useCostPresentation of data to user