NRDC TV Energy Efficiency Research
TV International Stakeholder Meeting San Francisco, California
June 28, 2005
Peter Ostendorp
Research Analyst
Ecos Consulting
(970)259-6801 ext. 307
Little information on TV power use
What test methods are available?
Measures black and white CRTs
Measures color CRTs
Measures new display types
Reflects real world power consumption
DOE method �
JEITA method � �
IEC 62087 � � �
Our Field Test Method
• Measured TV power use in retail setting with WattsUp? Pro power meter
• Used showroom screen settings
• Measured average power over 2 minutes using standard test clip
• Digital Video Essentials video clip used as reference material
Power Consumption in Direct View and Projection TVs (NRDC/Ecos)
0
50
100
150
200
250
300
350
400
450
500
0 500 1000 1500 2000
Act
ive
Mo
de
Po
wer
(w
atts
)
Plasma Projection LCD CRT
Screen Area (square inches)
0
50
100
150
200
250
300
350
400
450
500
0 500 1000 1500 2000
Act
ive
Mo
de
Po
wer
(w
atts
)
LCD CRT
Power Consumption in Direct View and Projection TVs (NRDC/Ecos and AGO)
Screen Area (square inches)
Plasma Projection
How do we fairly gauge efficiency in TVs?
Lumens/watt kWh/year
watts ? in2
Different Trends for Different Technologies
Power Consumption Trends in Direct View and Projection TVs
0
50
100
150
200
250
300
350
400
450
500
0 500 1000 1500 2000
Act
ive
Mo
de
Po
wer
(w
atts
)
Screen Area (square inches)
Direct View
Projection
0.35 watts per square inch
0.15 watts per square inch
Room for efficiency improvements in all technologies
0.0
0.1
0.2
0.3
0.4
0.5
0.6
CRT LCD PDP
Eff
icie
ncy
(w
atts
/sq
uar
e in
ch)
Australia results (n=104)
Projection
NRDC/Ecos results (n=25)
Future technologies provide hope of increased efficiency
Screen size (inches) 0 10 20 30 40
Ave
rage
Pow
er C
onsu
mpt
ion
(wat
ts)
1
10
100
1000
CRT
LCD
Color FED
Itoh S and Tanaka M. “Current Status of Field Emission Displays.” Proceedings of the IEEE. Vol. 90, No. 4. April 2002.
Energy Use of TVs and Home Appliances
TVs Appliances 700
600
500
400
300
200
100
0
Active Mode
Standby Mode
An
nu
al E
ner
gy
Use
(kW
h)
< 30" Direct 30 - 40" > 40" Direct Projection Washing Dishw asher Refrigerator, View TV Direct View View TV TV machine 22.5 cu ft.
TV
What have we learned?
• TV models of given size can vary widely in power consumption while providing similar resolution picture even for models of the same screen technology
• Direct view display technologies follow a similar efficiency trend; no one technology today stands out as efficient or inefficient
• Projection display technologies follow a separate efficiency trend due to fixed power consumption of projection bulbs
• Wide spread in efficiency means opportunity to encourage most efficient models
• Demand for an active mode test method
Power use can vary significantly based on image displayed
0
10
20 30
40
50
60 70
80
90
0 20 40 60 80 100 120
Power Consumption in 24" CRT TV
Elapsed Time (seconds)
Act
ive
Mo
de
Po
wer
(wat
ts)
Bright image
Dark image
Bright showroom settings affect power consumption in many TVs
Effect of Screen Settings on TV Power Consumption
0 100 200 300 400
32" LCD
50" PDP
Average Power Consumption (watts)
Factory default screen settings
DVE calibrated screen settings
32" CRT
27" CRT
32" CRT
Screen settings can even affect new LCD TVs with backlight controls
0 25 50 75 100 125 150 175
100% backlight brightness
brightness
0% backlight brightness
LCD Backlight Settings and Power Consumption
23" LCD TV
32" LCD TV
Average Active Mode Power (watts)
50% backlight
~ 14% range in power use observed
How to feed the signal?
Resolution of test signal can matter
0 10 20 30 40 50 60 70 80 90 100
S-video
RCA connectors
broadcast
Resolution of Test Signal and Average Power Consumption
DTV over-air
Component 480i
Component 480p
Component 720p
Active Mode Power Consumption (watts)
5% - 10% increase in power consumption using digital signals
What is a good TV test method?
• Easy to Conduct
– A trained technician should be able to quickly and easily perform the test
• Reproducible
– Test setup should be clear enough that results do not vary with lab or technician
• Robust
– Can measure all types of TVs, regardless of display technology (CRT, LCD, PDP, etc.)
– No significant changes in test procedure would be required for future technologies
• Representative
– Should indicate real world power consumption of TV
Questions?
Peter Ostendorp
Research Analyst
Ecos Consulting
(970)259-6801 ext. 307