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Fraunhofer USA Center for Sustainable Energy Systems
Energy Consumption of Consumer Electronics
in. U.S. Homes in 2017
Final Report to the Consumer Technology Association
by Bryan Urban, Kurt Roth, Mahendra Singh, and Duncan Howes
December 2017
Bryan Urban, Senior Technical Staff
burban@cse.fraunhofer.org +1 (617) 714-6514
Dr. Kurt Roth, Director of Building Energy Systems
kroth@cse.fraunhofer.org +1 (617) 575-7256
Fraunhofer USA Center for Sustainable Energy Systems 2
Disclaimer
This report was commissioned by the Consumer Technology Association (CTA) on terms specifically
limiting Fraunhofer USA’s liability. Our conclusions are the results of the exercise of our best professional
judgment, based in part upon materials and information provided to us by the Consumer Technology
Association and others. Use of this report by any third party for whatever purposes should not, and does
not, absolve such third party from using due diligence in verifying the report’s contents.
Any use which a third party makes of this document, or any reliance on it, or decisions to be made based
on it, are the responsibility of such third party. Fraunhofer USA accepts no duty of care or liability of any
kind whatsoever to any such third party, and no responsibility for damages, if any, suffered by any third
party as a result of decisions made, or not made, or actions taken, or not taken, based on this document.
This report may be reproduced only in its entirety, and may be distributed to third parties only with the
prior written consent of the Consumer Technology Association.
Fraunhofer USA Center for Sustainable Energy Systems 3
Table of Contents
List of Acronyms and Abbreviations ......................................................................................................................................... 7
ACKNOWLEDGEMENTS ............................................................................................................................................................. 8
EXECUTIVE SUMMARY.............................................................................................................................................................. 9
1 INTRODUCTION .......................................................................................................................................................... 10
1.1 Approach ............................................................................................................................................................................ 10
1.2 Organization ....................................................................................................................................................................... 10
2 METHODS................................................................................................................................................................... 11
2.1 Device Category Selection .................................................................................................................................................. 11
2.2 Energy Consumption Analysis ............................................................................................................................................ 11
2.2.1 Installed Base ............................................................................................................................................................... 11
2.2.2 Power Draw by Mode .................................................................................................................................................. 11
2.2.3 Annual Usage by Mode ................................................................................................................................................ 12
2.3 Uncertainty Analysis ........................................................................................................................................................... 12
3 RESULTS AND CONCLUSIONS ...................................................................................................................................... 13
3.1 Results ................................................................................................................................................................................ 13
3.2 Trends ................................................................................................................................................................................ 16
3.2.1 Televisions ................................................................................................................................................................... 16
3.2.2 Set-Top Boxes .............................................................................................................................................................. 16
3.2.3 Video Game Consoles .................................................................................................................................................. 17
3.2.4 Computers ................................................................................................................................................................... 17
3.2.5 Monitors ...................................................................................................................................................................... 18
3.2.6 Network Devices .......................................................................................................................................................... 18
3.3 Uncertainty Analysis ........................................................................................................................................................... 19
3.4 Future Research ................................................................................................................................................................. 19
3.5 References ......................................................................................................................................................................... 20
4 COMPUTERS ............................................................................................................................................................... 21
4.1 Installed Base ..................................................................................................................................................................... 21
4.2 Unit Energy Consumption .................................................................................................................................................. 22
4.2.1 Power Draw ................................................................................................................................................................. 22
4.2.2 Usage ........................................................................................................................................................................... 25
4.2.3 Unit Energy Consumption ............................................................................................................................................ 30
4.3 Annual Energy Consumption .............................................................................................................................................. 30
4.3.1 Uncertainty Analysis .................................................................................................................................................... 30
4.3.2 Comparison with Prior Estimates ................................................................................................................................. 33
4.4 References ......................................................................................................................................................................... 33
5 MONITORS ................................................................................................................................................................. 35
5.1 Installed Base ..................................................................................................................................................................... 35
5.2 Unit Energy Consumption .................................................................................................................................................. 36
5.2.1 Power Draw ................................................................................................................................................................. 36
5.2.2 Usage ........................................................................................................................................................................... 37
5.2.3 Unit Energy Consumption ............................................................................................................................................ 38
5.3 Annual Energy Consumption .............................................................................................................................................. 38
5.3.1 Uncertainty Analysis .................................................................................................................................................... 38
5.3.2 Comparison with Prior Estimates ................................................................................................................................. 39
5.4 References ......................................................................................................................................................................... 39
6 NETWORK EQUIPMENT .............................................................................................................................................. 40
6.1 Installed Base ..................................................................................................................................................................... 40
6.2 Unit Energy Consumption .................................................................................................................................................. 41
6.2.1 Power Draw ................................................................................................................................................................. 41
6.2.2 Usage ........................................................................................................................................................................... 42
6.2.3 Unit Energy Consumption ............................................................................................................................................ 43
6.3 Annual Energy Consumption .............................................................................................................................................. 43
6.3.1 Uncertainty Analysis .................................................................................................................................................... 43
6.3.2 Comparison with Prior Estimates ................................................................................................................................. 44
6.4 References ......................................................................................................................................................................... 44
7 TELEVISIONS ............................................................................................................................................................... 46
7.1 Installed Base ..................................................................................................................................................................... 46
Fraunhofer USA Center for Sustainable Energy Systems 4
7.1.1 Display Type ................................................................................................................................................................. 47
7.1.2 Screen Size and Age ..................................................................................................................................................... 48
7.2 Unit Energy Consumption .................................................................................................................................................. 49
7.2.1 Power Draw ................................................................................................................................................................. 49
7.2.2 Usage ........................................................................................................................................................................... 51
7.2.3 Unit Energy Consumption ............................................................................................................................................ 51
7.3 Annual Energy Consumption .............................................................................................................................................. 52
7.3.1 Uncertainty Analysis .................................................................................................................................................... 52
7.3.2 Comparison with Prior Estimates ................................................................................................................................. 55
7.4 References ......................................................................................................................................................................... 55
8 SOUNDBARS ............................................................................................................................................................... 57
8.1 Installed Base ..................................................................................................................................................................... 57
8.2 Unit Energy Consumption .................................................................................................................................................. 57
8.2.1 Power Draw ................................................................................................................................................................. 57
8.2.2 Usage ........................................................................................................................................................................... 60
8.2.3 Unit Energy Consumption ............................................................................................................................................ 61
8.3 Annual Energy Consumption .............................................................................................................................................. 61
8.3.1 Comparison with Prior Estimates ................................................................................................................................. 61
8.4 References ......................................................................................................................................................................... 62
9 SET-TOP BOXES .......................................................................................................................................................... 63
9.1 Installed Base ..................................................................................................................................................................... 63
9.2 Unit Energy Consumption .................................................................................................................................................. 64
9.2.1 Power Draw ................................................................................................................................................................. 64
9.2.2 Usage ........................................................................................................................................................................... 64
9.2.3 Unit Energy Consumption ............................................................................................................................................ 65
9.3 Annual Energy Consumption .............................................................................................................................................. 65
9.3.1 Uncertainty Analysis .................................................................................................................................................... 65
9.3.2 Comparison with Prior Estimates ................................................................................................................................. 66
9.4 References ......................................................................................................................................................................... 67
10 VIDEO GAME CONSOLES ............................................................................................................................................. 68
10.1 Installed Base ..................................................................................................................................................................... 68
10.2 Unit Energy Consumption .................................................................................................................................................. 68
10.2.1 Power Draw ................................................................................................................................................................. 69
10.2.2 Usage ........................................................................................................................................................................... 71
10.2.3 Unit Energy Consumption ............................................................................................................................................ 72
10.3 Annual Energy Consumption .............................................................................................................................................. 73
10.3.1 Uncertainty Analysis .................................................................................................................................................... 74
10.3.2 Comparison with Prior Estimates ................................................................................................................................. 75
10.4 References ......................................................................................................................................................................... 76
11 OTHER DEVICES .......................................................................................................................................................... 77
11.1 References ......................................................................................................................................................................... 80
APPENDIX A: CE USAGE SURVEYS ........................................................................................................................................... 82
A.1 Televisions and Soundbars ................................................................................................................................................. 83
A.2 Video Game Consoles ........................................................................................................................................................ 86
A3. Computers ................................................................................................................................................................................ 90
List of Figures
Figure ES-1. Trends in consumer electronics energy use. ................................................................................................................. 9
Figure ES-2. Unit energy consumption and annual energy consumption by mode for devices studied in depth............................. 9
Figure 2-1. Example of device energy use calculation methodology. ............................................................................................. 11
Figure 3-1. Installed base and unit and annual energy consumption of devices studied in depth. ................................................ 13
Figure 3-2. Unit and annual energy consumption by mode for devices studied in depth. ............................................................. 15
Figure 3-3. Unit and annual energy consumption (all devices, by category). ................................................................................. 15
Figure 3-4. Annual energy consumption breakdown by mode for devices studied in depth. ........................................................ 15
Figure 3-5. Trends in consumer electronics energy use. Source: Current Study, FhCSE (2014, 2011), TIAX (2007) ....................... 16
Figure 3-6. Trends in television energy use. ................................................................................................................................... 16
Figure 3-7. Trends in set-top box energy use. ................................................................................................................................. 17
Fraunhofer USA Center for Sustainable Energy Systems 5
Figure 3-8. Trends in video game console energy use. ................................................................................................................... 17
Figure 3-9. Trends in energy use estimates for computers............................................................................................................. 18
Figure 3-10. Trends in energy use estimates for monitors. ............................................................................................................ 18
Figure 3-11. Trends in energy use estimates for network devices. ................................................................................................. 18
Figure 4-1. Power draw of ENERGY STAR qualified desktop and portable computers available from 2013-2017. ........................ 23
Figure 4-2. Manual power management behaviors of computers. ................................................................................................ 26
Figure 4-3. Likelihood of manual power management behaviors after a usage session. ............................................................... 27
Figure 4-4. Power state of all computers just prior to the first session of the day. ........................................................................ 28
Figure 4-5. Automatic power management setting prevalence of computers. .............................................................................. 28
Figure 5-1. Monitors per computer. ............................................................................................................................................... 35
Figure 5-2. Size of LCD monitors sold by year. ................................................................................................................................ 35
Figure 6-1. Home network and internet penetration. .................................................................................................................... 40
Figure 6-2. Idle mode power draw of network equipment, models shipped in 2015. .................................................................... 42
Figure 7-1. TV ownership distribution. ........................................................................................................................................... 46
Figure 7-2. Televisions by display type. .......................................................................................................................................... 47
Figure 7-3. Televisions by display type and usage priority. ............................................................................................................. 48
Figure 7-4. Televisions by diagonal screen size and age. ................................................................................................................ 48
Figure 7-5. On-mode power regressions for LCD and Plasma TVs. ................................................................................................. 49
Figure 7-6. Market share of ENERGY STAR qualified televisions by year. ....................................................................................... 50
Figure 7-7. Unit energy consumption by usage priority and display type for televisions. .............................................................. 51
Figure 7-8. Annual energy consumption by TV priority and display type. ...................................................................................... 52
Figure 7-9. Television usage per day per person (age 2+) for several activities. ............................................................................. 54
Figure 8-1. Power draw of ENERGY STAR qualified soundbars by number of channels. ................................................................ 58
Figure 8-2. Power draw levels measured for a multi-channel soundbar. ....................................................................................... 60
Figure 9-1. Power draw of subscription set-top boxes by type. ..................................................................................................... 64
Figure 9-2. Installed base, UEC, and AEC of subscription set-top boxes by type. ........................................................................... 66
Figure 10-1. Installed base of video game consoles........................................................................................................................ 68
Figure 10-2. Active mode power draw trends of video game consoles over time. ......................................................................... 70
Figure 10-3. Daily time spent in active and navigation modes by console type. ............................................................................ 71
Figure 10-4. Unit energy consumption of video game consoles. .................................................................................................... 73
Figure 10-5. Annual energy consumption of video game consoles. ............................................................................................... 74
Figure 11-1. AEC, installed base, and UEC of other devices evaluated in less detail. ..................................................................... 78
List of Tables
Table 3-1. Energy used by consumer electronics in U.S. homes in 2017, devices studied in depth. .............................................. 13
Table 3-2. Energy used by consumer electronics in homes in 2017, all devices. ............................................................................ 14
Table 4-1. Installed base estimates for computers. ........................................................................................................................ 21
Table 4-2. Installed base (millions) for computers. ......................................................................................................................... 21
Table 4-3. Average power draw by mode (W) by ENERGY STAR status and year for computers. .................................................. 22
Table 4-4. ENERGY STAR market share for desktop computers. ..................................................................................................... 22
Table 4-5. Real-world power draw adjustment factors (F) for computers. .................................................................................... 23
Table 4-6. Power draw by mode (W) for the installed base of desktop and portable computers. ................................................. 24
Table 4-7. Usage by mode (h/day) for computers. ......................................................................................................................... 25
Table 4-8. Daily time spent actively using computers (h/day) by priority. ..................................................................................... 25
Table 4-9. Survey questions used to infer overnight power state. ................................................................................................ 28
Table 4-10. Average number and duration of typical usage sessions by time of day. .................................................................... 29
Table 4-11. Time spent by mode for computers. ............................................................................................................................ 29
Table 4-12. Unit and annual energy consumption for computers. ................................................................................................ 30
Table 4-13. Uncertainty estimates for computers. ......................................................................................................................... 31
Table 4-14. Active and gaming time (h/day) and dedicated graphics for computers. .................................................................... 32
Table 4-15. Current and prior energy consumption estimates for desktop computers. ................................................................ 33
Table 4-16. Current and prior energy consumption estimates for portable computers. ................................................................ 33
Table 5-1. Installed base for monitors. ........................................................................................................................................... 35
Fraunhofer USA Center for Sustainable Energy Systems 6
Table 5-2. Computer monitor sales (millions) in North America by year and size bin. ................................................................... 37
Table 5-3. Power draw for monitors by screen size bin for 2014-2016. ......................................................................................... 37
Table 5-4. Power draw for the installed base of monitors. ............................................................................................................ 37
Table 5-5. Daily usage of monitors by mode and prior estimates.................................................................................................. 37
Table 5-6. Unit and annual energy consumption estimates for monitors. ..................................................................................... 38
Table 5-7. Prior energy consumption estimates for monitors. ....................................................................................................... 39
Table 6-1. Installed base (millions) for network devices. ................................................................................................................ 40
Table 6-2. Unit shipments (millions) for network devices. ............................................................................................................. 41
Table 6-3. Installed base (millions) for network devices. ................................................................................................................ 41
Table 6-4. Power draw (W) by mode for network equipment. ....................................................................................................... 42
Table 6-5. UEC and AEC calculations for network equipment. ....................................................................................................... 43
Table 6-6. Uncertainty estimates for network devices. .................................................................................................................. 43
Table 6-7. Prior energy consumption estimates for broadband gateways (modems and IADs). .................................................... 44
Table 6-8. Prior energy consumption estimates for local network equipment. ............................................................................. 44
Table 7-1. Installed base estimates for televisions. ........................................................................................................................ 46
Table 7-2. TV ownership distribution. ............................................................................................................................................. 46
Table 7-3. Distribution of televisions by display type. .................................................................................................................... 47
Table 7-4. Installed base by usage priority and display type. ......................................................................................................... 47
Table 7-5. Screen size and age by display type and usage priority. ................................................................................................ 48
Table 7-6. Power draw estimates for TVs by usage priority and display type. ............................................................................... 49
Table 7-7. Television power regressions by screen area, display type, and year. ........................................................................... 49
Table 7-8. Time spent in on-mode by usage priority and display type. .......................................................................................... 51
Table 7-9. Unit energy consumption estimates for TVs by usage priority and display type. .......................................................... 51
Table 7-10. Annual energy consumption breakdown for televisions.............................................................................................. 52
Table 7-11. Uncertainty estimates for televisions. ......................................................................................................................... 53
Table 7-12. Prior energy consumption estimates for TVs. .............................................................................................................. 55
Table 8-1. Installed base estimates for soundbars. ........................................................................................................................ 57
Table 8-2. Installed base of soundbars (millions) by TV priority and number of speaker channels. ............................................... 57
Table 8-3. Power (W) measurements for nine soundbars. ............................................................................................................. 59
Table 8-4. Power draw (W) by mode estimates for measured soundbars. .................................................................................... 59
Table 8-5. Power draw (W) estimates used to calculate UEC for soundbars. ................................................................................. 60
Table 8-6. Usage estimates for soundbars. ..................................................................................................................................... 60
Table 8-7. UEC and AEC calculation for soundbars. ........................................................................................................................ 61
Table 8-8. Prior energy consumption estimates for audio categories. ........................................................................................... 62
Table 9-1. Installed base (millions) estimates by year for subscription set top boxes. ................................................................... 63
Table 9-2. Average power draw across models by year shipped for set top boxes. ....................................................................... 64
Table 9-3. Unit energy consumption by year for subscription set top boxes. ................................................................................ 65
Table 9-4. Annual energy consumption (TWh) by year for subscription set top boxes. ................................................................. 65
Table 9-5. Prior energy consumption estimates for subscription STBs. .......................................................................................... 66
Table 10-1. Installed base of video game consoles. ........................................................................................................................ 68
Table 10-2. Installed base and power draw by mode of video game systems. ............................................................................... 70
Table 10-3. Annual usage by mode (hours/year) for video game consoles. ................................................................................... 71
Table 10-4. Power management for video game consoles. ............................................................................................................ 72
Table 10-5. Unit and annual energy consumption for video game systems. .................................................................................. 73
Table 10-6. Uncertainty estimates for video game consoles. ......................................................................................................... 74
Table 10-7. Prior energy consumption estimates for video game consoles. .................................................................................. 75
Table 11-1. Installed base, unit and annual energy consumption (AEC) for other devices. ............................................................ 77
Table 11-2. Average power draw by mode (W) for other devices. ................................................................................................. 79
Table 11-3. Annual usage by mode (hours) for other devices. ....................................................................................................... 80
Fraunhofer USA Center for Sustainable Energy Systems 7
List of Acronyms and Abbreviations
AEC Annual Electricity Consumption
CE Consumer Electronics
CEA Consumer Electronics Association
CT Consumer Technology
CTA Consumer Technology Association
CRT Cathode Ray Tube
DOE U.S. Department of Energy
DTA Digital Terminal/Transport/Television Adapter
DVR Digital Video Recorder
EPA U.S. Environmental Protection Agency
FhCSE Fraunhofer Center for Sustainable Energy Systems
GPU Graphics Processing Unit
IAD Integrated Access Device
STB Set-top Box
TEC Total/Typical Energy Consumption
TV Television
TWh Terawatt-hour
UEC Unit Electricity Consumption
UHD Ultra High Definition
Fraunhofer USA Center for Sustainable Energy Systems 8
ACKNOWLEDGEMENTS
The authors would like to express our gratitude to the following people and organizations for their support
in making this report possible.
We thank the project sponsors at the Consumer Technology Association, and especially Douglas Johnson,
Vice President, Technology Policy, for leading the project at CTA. In addition, we thank Steve Koenig,
Senior Director, Market Research, for providing market data and consultations on installed base,
estimates and Meenakshi Ramasubramanian, Senior Research Analyst, for her input and collaboration on
the CE Usage Survey.
We would also like to thank Paul Gagnon with IHS Markit for providing computer monitor data and
Ian Olgeirson of SNL Kagan for providing set-top box data.
Finally, we thank our reviewers for providing thoughtful feedback on the draft final report:
Robert Turner Arris
Steve Dulac AT&T
Steve Belitech Beletich Associates
Debbie Fitzgerald Cable Labs
Robert White Dell
Sylvie Feindt DIGITALEUROPE
Paolo Tosoratti European Commission
Mugurel-George Paunescu European Commission
Robert Nuij European Commission
Antoine Durand Fraunhofer Institute for Systems and Innovation Research
Louis-Benoit Desroches Lawrence Berkeley National Laboratory
Bruce Nordman Lawrence Berkeley National Laboratory
Evan Mills Lawrence Berkeley National Laboratory
Samuel Thomas International Energy Agency
John Dulac International Energy Agency
Mark Ellis Mark Ellis & Associates
Paul Glist National Cable and Telecommunications Association
Augustine Orumwense Natural Resources Canada
Pierre Delforge Natural Resources Defense Council
Eden Brandeis Nintendo of America
Hans-Paul Siderius SenterNovem
Jonathan Koomey Stanford University
Fraunhofer USA Center for Sustainable Energy Systems 9
EXECUTIVE SUMMARY
The Consumer Technology Association (CTA) commissioned this study to quantify the electricity used by
consumer electronics in U.S. households in 2017. Consumer electronics include devices, such as
televisions and computers, intended for everyday use in homes. Relative to other energy end uses,
electronics tend to have shorter product cycles, varied usage patterns, and rapid adoption. As a result,
their characteristics can change dramatically in just a few years, providing a need for up-to-date energy
consumption assessments, especially for informing energy policy decisions. This study represents the
fourth of its kind, enabling a trend analysis.
We estimate that 3.4 billion consumer electronic devices consumed about 143±9 TWh in 2017. This
represents about 10% of residential sector and 4% of total U.S. electricity consumption. Powering these
devices costs about $18 billion annually. Per-household, this is about 1,205 kWh or $155 per year. Relative
to prior year estimates, the 2017 energy total was less by about 11% (2006), 26% (2010), and 14% (2013).
The decreases since 2010 are driven largely by the diminishing installed base of CRT televisions.
Results for individual device categories were based on a bottom-up approach used to estimate the
installed base, typical annual usage, and power draw by mode. Thirteen categories studied in-depth
account for one third of all installed devices and nearly 80% of the total energy consumption (Figure ES-
2). The other devices, studied in less depth, are covered in Section 11 (also Table 3-2). Three U.S. phone
surveys were fielded to identify the installed base and usage patterns of computers, televisions and
soundbars, and video game consoles. Survey responses served as inputs into more detailed energy use
models. Uncertainty estimates, developed for priority categories, were typically within about ±15%.
Figure ES-1. Trends in consumer electronics energy use.
Figure ES-2. Unit energy consumption and annual energy consumption by mode for devices studied in depth.
2.1
2.9
3.8
3.4
2006 '10 '13 '17
UNITS
(billions)
plugged in during past month
78
67
44 42
2006 '10 '13 '17
UEC
(kWh/yr)
161
193
167
143
2006 '10 '13 '17
AEC
(TWh)
42
46
50
52
54
65
79
80
107
110
123
188
246
0 50 100 150 200 250
Portable Computer
Cable DTA (STB)
Thin Client (STB)
Local Network Equipment
Broadband Modem
Soundbar
Video Game Console
Monitor
Integrated Access Device
Non-DVR (STB)
Television
DVR (STB)
Desktop Computer
ACTIVE IDLE SLEEP OFF
UEC (kWh/yr) 0.4
1
1
2
2
5
8
8
9
10
11
18
35
0 10 20 30
Broadband Modem
Soundbar
Cable DTA (STB)
Local Network Equipment
Thin Client (STB)
Portable Computer
Monitor
Video Game Console
Integrated Access Device
DVR (STB)
Non-DVR (STB)
Desktop Computer
Television
ACTIVE IDLE SLEEP OFF
AEC (TWh)
Fraunhofer USA Center for Sustainable Energy Systems 10
1 INTRODUCTION
The Consumer Technology Association (CTA) commissioned this study to quantify the electricity
consumption of consumer electronics in U.S. households in 2017. This study is the fourth of its kind,
characterizing consumer electronics energy use for the years 2006, 2010, and 2013 (TIAX 2007; FhCSE
2011, 2014).
Consumer electronics include a wide array of devices, like computers and televisions, intended for
everyday use in homes. They do not include appliances or hardware related to heating, cooling, or lighting
end uses. Relative to other end uses, the characteristics of consumer electronics typically change very
quickly due to innovation, short product cycles and lifetimes, evolving usage patterns, and rapid
technology adoption. As a result, the installed base of many product categories can change dramatically
in just a few years and new categories emerge that did not exist in prior studies.
New smart home technologies are blurring the lines between consumer electronics and other end-uses.
Devices like digital personal assistants (Amazon Echo and Google Home), smart thermostats, and
connected lighting are changing how people use energy in the home. While we did not include these
devices in this study, they are growing in importance, and may be included in future editions of this report.
Such rapid changes make it essential to regularly develop up-to-date and accurate energy assessments.
For instance, if obsolete data are used to inform energy policymaking, the resulting programs could be
less likely to achieve their end goals. Consequently, the Consumer Technology Association commissioned
Fraunhofer to perform this study to provide current, high-quality data to inform energy policy decisions.
1.1 Approach
This study followed a similar approach as the three prior studies:
1. Develop preliminary Annual Energy Consumption (AEC) estimates for a long list of devices
2. Select priority device categories to study in depth with a more refined analysis
3. Develop refined AEC estimates for the selected priority categories
4. Compare current energy consumption characteristics with prior estimates
5. Compose a Draft Final Report and undergo peer review
6. Publish a Final Report to the CTA suitable for widespread distribution
1.2 Organization
The report is organized into the following sections:
Section 2 Methodology used to characterize energy consumed by each device category.
Section 3 Results and conclusions.
Sections 4-10 Detailed supporting analysis for the priority device categories studied in depth.
Section 11 Supporting analysis for all remaining “other” device categories studied in less depth.
Appendix A Consumer Electronics Usage Survey Questions
Fraunhofer USA Center for Sustainable Energy Systems 11
2 METHODS
2.1 Device Category Selection
While it would be preferable to evaluate the annual energy consumption of all device categories in depth,
time and scope constraints led us to focus on a subset of categories where a more refined analysis would
yield the greatest value. Consequently, in conjunction with CTA, we selected thirteen categories for in-
depth analysis based on the magnitude and uncertainty of preliminary AEC estimates (higher more likely
to be selected, see Table 3-1 and Table 3-2). The remaining other categories were studied in less depth in
Section 11. Since few categories account for the vast majority of the total energy consumption, this
approach has a minor impact on the collective energy estimate accuracy.
2.2 Energy Consumption Analysis
To evaluate device energy consumption, we used a bottom-up approach (Figure 2-1). For each device
category, we developed estimates for the average power draw (W) and usage (hours/year) by mode.
Multiplying power and usage yields the unit electricity consumption (UEC in kWh/year) by mode. The sum
over all modes equals the total UEC. Finally, the product of the UEC and installed base (millions of units)
equals the annual energy consumption (AEC in TWh). Prior studies followed similar methods (LBNL 2001;
ADL 2002, TIAX 2006). The modes in Figure 2-1 are illustrative and were tailored for each specific category
based on their actual power modes. A succinct overview of the model components follows.
Figure 2-1. Example of device energy use calculation methodology.
2.2.1 Installed Base
The installed base represents the total number of devices in U.S. homes that were plugged in at least once
during the past month. Devices that were owned but not plugged in were not counted. Most installed
base estimates came from market research studies (most notably ownership and sales reports from CTA),
the CE Usage Survey (see Appendix A), and, to a lesser extent, ownership and sales data from other
sources. Typically, the installed base estimates have the least uncertainty of any AEC component.
2.2.2 Power Draw by Mode
All consumer electronics have at least two basic operating modes – on and off – and most have others
such as idle, standby, sleep, hibernate, or charging. Within a specific power mode, device power draw can
vary appreciably due to changes in operation such as variable processor utilization, display brightness, or
audio signal. For each device category, we identified the most relevant power modes and developed
estimates for the average power draw of its installed base in each mode, attempting to reflect real-world
usage scenarios as well as possible.
Ideally, power draw estimates would be identified by taking measurements of actual devices deployed in
a large sample (several hundreds) of demographically representative U.S. households. As the cost and
x
ACTIVE
SLEEP
OFF
=
x
x
UEC
x
IB AEC
=
ANNUAL
USAGE
(hours/yr)
Tactive
Tsleep
Toff
MODE
Pactive
Psleep
Poff
POWER
DRAW
(W)
UECsleep
UECoff
UNIT ELECTRICITY
CONSUMPTION
(kWh/yr)
UECactive
Σ
TOTAL DEVICE
UEC (kWh/yr)
ANNUAL ELECTRICITY
CONSUMPTION
(TWh)
=
=
=
INSTALLED BASE
(millions)
Fraunhofer USA Center for Sustainable Energy Systems 12
effort required was well beyond the scope of this project, we instead relied on several other sources to
estimate power draw by mode, including:
• Energy consumption characterization studies
• Field measurement campaigns
• Public product power draw databases (ENERGY STAR, California Energy Commission)
• Measurements by CTA member companies
• Targeted measurements by Fraunhofer
2.2.3 Annual Usage by Mode
For most device categories, identifying the average time spent in different power modes is the most
challenging element to estimate accurately.
Ideally, usage estimates would be based on sustained field measurement campaigns that record the time
devices spent in different modes. To provide accurate results, such studies would need a sample of at
least several hundred demographically representative U.S. households, over the course of weeks or
months. Instead, we used other sources to estimate annual usage by mode, including:
• The CE Usage Survey (see Appendix A)
• Data from prior field measurement campaigns1
• Data from prior energy consumption characterization studies
The CE Usage Survey responses served as inputs into more refined models used to assess computer,
monitor, and video game console usage. We posed more questions for computers and video game
consoles because they have substantial AEC values that depend strongly on usage behaviors and power
management settings. We also fielded surveys on televisions and soundbars, the latter having not been
studied in detail before.
2.3 Uncertainty Analysis
For the first time in this series of studies, we characterized the uncertainty of the AEC estimates for four
categories that collectively account for the majority of consumption: Televisions; Desktop Computers;
Video Game Consoles; and Set-Top-Boxes. For each of these categories, we identified the major
component sources of uncertainty, and estimated their potential impact on the calculated AEC estimates.
While it is often desirable to identify precise confidence intervals for uncertainty, this is not always
possible given the many “known unknowns.” Instead, we used a combination of statistical methods,
scenario analysis, and professional judgment to assess the likely range of AEC values by varying the most
influential modeling assumptions under plausible scenarios.
For the portions of the analysis that relied on survey data, we calculated standard errors to identify
approximate 90% confidence intervals of key parameter estimates. Other sources of error may be even
more important, including bias in self-reporting and other modeling assumptions. As a result, for each
category, we performed a basic sensitivity analysis, calculating AEC in several different ways by varying
key assumptions and using different combinations or sources for the input parameters. For inputs that
have a range of possible values, we calculated realistic bounding scenarios.
This allowed us to identify key gaps in understanding, set future research priorities, and assess which
specific trends are likely to be significant.
1 Although useful, prior field measurement campaigns usually fall short of the ideal described due to a limited and biased (i.e., non-random and
unrepresentative) sample of households used and devices measured.
Fraunhofer USA Center for Sustainable Energy Systems 13
3 RESULTS AND CONCLUSIONS
3.1 Results
We estimate that 3.4 billion consumer electronic devices consumed about 143 TWh in 2017. This equals
about 10% of residential sector and 4% of total electricity consumption in the U.S. (DOE/EIA 2017).
Powering these devices costs about $18 billion annually. Per-household, this is about 1,205 kWh or $155
per year. The 2017 energy estimate is about 14% less than in 2013 (FhCSE 2014).
The thirteen device categories studied in depth account for one third of all devices installed and represent
nearly 80% of the total energy consumption (Table 3-1 and Table 3-2). Televisions, set-top boxes, and
computers remain the highest consuming categories, collectively representing just over half (56%) of the
total. About one quarter of all devices are portable, yet these use less than 5% of the total energy.
Table 3-1. Energy used by consumer electronics in U.S. homes in 2017, devices studied in depth.
CATEGORY DEVICE
UNITS
(millions)
POWER (W)
USAGE (h/yr)
UEC
AEC
ON
IDLE
OFF
ON
IDLE
OFF
(kWh/yr)
TWh
%
MULTIMEDIA
Television
284
77
-
1.0
1,410
-
7,350
123
35
24%
Video Game Console
105
63
52
3.2
560
200
8,000
79
8.3
6%
Soundbar
20
14
9.0
5.0
1,345
2,025
5,390
65
1.3
1%
SET-TOP BOX
DVR
53
22
19
-
-
-
-
188
10
7%
(subscriber)
Non-DVR
103
13
12
-
-
-
-
110
11
8%
Thin Client
41
7
6
-
-
-
-
50
2.1
1%
Cable DTA
31
6
6
-
-
-
-
46
1.4
1%
COMPUTER
Desktop Computer
72
65
2.7
1.2
3,635
2,110
3,015
246
18
12%
Portable Computer
122
14
0.7
0.3
2,585
2,330
3,845
42
5.1
4%
Monitor
101
31
0.8
0.5
2,455
3,255
3,050
80
8.1
6%
NETWORK
Integrated Access Dev.
85
13.4
-
1.5
7,825
-
935
107
9.1
6%
Broadband Modem
8
6.8
-
0.1
7,825
-
935
54
0.4
0%
Local Network Equip.
39
6.6
-
1.0
7,825
-
935
52
2.0
1%
OTHER
Other Devices
2,321
-
-
-
-
-
-
14
32
22%
TOTAL/Wt.Avg.
3,385
-
-
-
-
-
-
42
143
100%
Note: Power modes identified in this summary table are approximate. See individual device sections for more detail.
Figure 3-1. Installed base and unit and annual energy consumption of devices studied in depth.
0 100 200 300
OTHER
Broadband Modem
Local Network Equip.
Integrated Access…
NETWORK
Portable
Monitor
Desktop
COMPUTER
Soundbar
Video Game
Cable DTA (STB)
Thin Client (STB)
DVR (STB)
Non-DVR (STB)
Television
MULTIMEDIA
UNITS (millions)
2,321
0 100 200 300
OTH
Mod
Wi-Fi
IAD
P
M
D
SB
VG
C-DTA
TC
DVR
N-DVR
TV
UEC (kWh/yr)
0 10 20 30
OTH
Mod
Wi-Fi
IAD
P
M
D
SB
VG
C-DTA
TC
DVR
N-DVR
TV
AEC (TWh)
Fraunhofer USA Center for Sustainable Energy Systems 14
Table 3-2. Energy used by consumer electronics in homes in 2017, all devices.
CATEGORY DEVICE
UNITS
(millions)
UEC
(kWh/yr)
AEC
(TWh)
AEC
(%)
MULTIMEDIA
1,356
67
91
64%
VIDEO
Television
284
123
35
24%
Digital Picture Frame
50
6.5
0.3
0%
Video Projector
4
55
0.2
0%
SET-TOP
Subscriber DVR
53
188
10
7%
Subscriber Non-DVR
103
110
11
8%
Subscriber Thin Client
41
50
2.1
1%
Subscriber Cable DTA
31
46
1.4
1%
Standalone DVR
2
275
0.6
0%
Over-the-air DTA
7
30
0.2
0%
Digital Media Streaming
77
39
3.0
2%
Video Cassette Recorder
39
34
1.3
1%
AUDIO
AV Receiver w/ Surround
43
65
2.8
2%
Computer Speakers
80
44
3.5
2%
Home Theater In-a-box
20
89
1.8
1%
Radio + Clock Radio
113
9
1.0
1%
Shelf Stereo + Compact
30
75
2.2
1%
Speaker Dock
70
19
1.3
1%
Sound Bar
20
65
1.3
1%
VG/DISC PLAYER
Video Game Console
105
79
8.3
6%
Blu-ray Player
48
14
0.7
0%
CD Player, standalone
42
18
0.7
0%
DVD Player
94
24
2.2
1%
IT + COMMUNICATIONS
1,110
45
50
35%
COMPUTER
Desktop Computer
72
246
18
12%
Portable Computer
122
42
5.1
4%
PERIPHERAL
Monitor
101
80
8.1
6%
External Storage Drive
89
17
1.5
1%
Web Camera
66
22
1.4
1%
Printer + Multi-function
97
12
1.2
1%
NETWORK
Integrated Access Device
85
107
9.1
6%
Broadband Modem
8
54
0.4
0%
Local Network Equipment
39
52
2.0
1%
PHONE
Cordless Phone
104
12
1.3
1%
Internet-based Phone
12
36
0.4
0%
Telephone Answering Device
11
14
0.2
0%
Mobile Non-Smart Phone
66
2.2
0.1
0%
Mobile Smart Phone
238
4.5
1.1
1%
PORTABLE DEVICES
920
3
3
2%
AUDIO
Bluetooth Headset
71
5.9
0.4
0%
Wireless Speaker
140
1
0.1
0%
VG/DISC PLAYER
Video Game
52
4.3
0.2
0%
DVD or Blu-ray Player
80
2.7
0.2
0%
Media Player, MP3 + CD
90
5.6
0.5
0%
INFO TECH
eReader
54
1.8
0.1
0%
GPS, handheld
68
1.3
0.1
0%
Smart watch + Wearable
64
0.6
0.04
0%
Tablet Computer
140
6.1
0.9
1%
VIDEO
Camcorder
54
2.3
0.1
0%
Digital Camera
107
0.3
0.0
0%
TOTAL/Wt. Avg.
3,385
42
143
100%
Notes: Highlighted categories were studied in depth in the current study.
Categories with borders were studied in depth in FhCSE (2014).
Fraunhofer USA Center for Sustainable Energy Systems 15
The unit electricity consumption varies across categories by a factor of five (Figure 3-2). Desktop
computers use the most energy per device, while televisions use the most energy overall. As in prior
studies, active modes accounted for a large majority of the overall annual energy consumption (70%,
Figure 3-4).
Figure 3-2. Unit and annual energy consumption by mode for devices studied in depth.
Figure 3-3. Unit and annual energy consumption (all devices, by category).
Figure 3-4. Annual energy consumption breakdown by mode for devices studied in depth.
42
46
50
52
54
65
79
80
107
110
123
188
246
0 50 100 150 200 250
Portable Computer
Cable DTA (STB)
Thin Client (STB)
Local Network Equipment
Broadband Modem
Soundbar
Video Game Console
Monitor
Integrated Access Device
Non-DVR (STB)
Television
DVR (STB)
Desktop Computer
ACTIVE IDLE SLEEP OFF
UEC (kWh/yr) 0.4
1
1
2
2
5
8
8
9
10
11
18
35
0 10 20 30
Broadband Modem
Soundbar
Cable DTA (STB)
Local Network Equipment
Thin Client (STB)
Portable Computer
Monitor
Video Game Console
Integrated Access Device
DVR (STB)
Non-DVR (STB)
Desktop Computer
Television
ACTIVE IDLE SLEEP OFF
AEC (TWh)
105
85
118
37
35
41
87
7
3
0 50 100 150
VIDEO
SET-TOP
COMPUTER
AUDIO
PERIPHERAL
VG/DISC PLAYER
NETWORK
PHONE
PORTABLE
UEC (kWh/yr)
35
30
23
14
12
12
12
3
3
0 10 20 30 40
VIDEO
SET-TOP
COMPUTER
AUDIO
PERIPHERAL
VG/DISC PLAYER
NETWORK
PHONE
PORTABLE
AEC (TWh)
0% 50% 100%
Soundbar
Desktop Computer
Portable Computer
Video Game Console
Cable DTA (STB)
Non-DVR (STB)
DVR (STB)
Thin Client (STB)
Television
Monitor
Local Network Equipment
Integrated Access Device
Broadband Modem
ACTIVE IDLE SLEEP OFF
ACTIVE
70%
IDLE
14%
SLEEP
13%
OFF
3%
Fraunhofer USA Center for Sustainable Energy Systems 16
3.2 Trends
The energy consumed by consumer electronics declined about 14% since 2013, continuing the trend that
started in 2010. On average, while devices consumed about the same per unit as in 2013, unit energy
consumption is nearly half (45%) that of 2006 values.
Meanwhile, the estimated number of devices installed2 has declined slightly (11%) for the first time since
2006. To a large extent, changes in total AEC are driven primarily by shifts in televisions and computers.
These top-level average values, however, mask significant changes within device categories that are
addressed below.
Figure 3-5. Trends in consumer electronics energy use.
Source: Current Study, FhCSE (2014, 2011), TIAX (2007)
3.2.1 Televisions
Televisions still account for the largest share of the total energy consumption. The number of installed
televisions had been increasing until about 2010, before starting to decline. More importantly, this decline
coincided with a shift from CRT to LCD displays that have far lower power densities. LCDs comprise about
84% of the installed base and CRTs only 7%. With most CRTs out of service, the sharply declining UEC
trend may be reaching an end. Usage patterns have remained relatively unchanged. Although screens
have gotten larger and resolution continues to improve, the power density and average power draw of
LCDs has continued to decline.
Figure 3-6. Trends in television energy use.
3.2.2 Set-Top Boxes
While the number of set-top boxes (STBs) has remained fairly flat in recent years, we estimate that their
AEC has declined by about 22% since 2012 (Figure 3-7). This change is mainly due to a slight decline in
2 We focused on devices that are installed (plugged in during the past month), and not simply owned. While the number of devices owned may
be increasing, many are not in regular use and do not consume energy.
2.1
2.9
3.8
3.4
2006 '10 '13 '17
UNITS
(billions)
plugged in during past month
78
67
44 42
2006 '10 '13 '17
UEC
(kWh/yr)
161
193
167
143
2006 '10 '13 '17
AEC
(TWh)
191
353
284
1995 '00 '05 '10 '13 '17
UNITS
(millions)
141
244
123
1995 '00 '05 '10 '13 '17
UEC
(kWh/yr)
26
67
35
1995 '00 '05 '10 '13 '17
AEC
(TWh)
Fraunhofer USA Center for Sustainable Energy Systems 17
fully-featured DVR and non-DVR boxes and a slight increase in thin-client boxes. A shift in technology
architecture that enables homes to rely on a single DVR unit to serve multiple thin clients in the home.
Unit energy consumption estimates in this category are based primarily on the industry’s voluntary
agreement, which includes third-party reporting of device energy consumption. Since the available
reports extend only through 2015, we made projections until the end of 2016. We expect results for 2017
to be similar.
Figure 3-7. Trends in set-top box energy use.
3.2.3 Video Game Consoles
Energy used by video game consoles has continued a steady decline that started around 2008, driven by
a recent drop in installed consoles and by shifts in the power draw characteristics. Power draw varies
strongly by console type and among different versions of the same console, as hardware and processing
capabilities can vary substantially. As consoles evolve rapidly, so do their energy usage patterns. Though
consoles are now serving more purposes (e.g., acting as media devices for watching video), the overall
usage time per console was similar to that estimated in prior studies. Standby modes account for about
one third of video game energy consumption, driven mainly by network-connected standby modes.
Figure 3-8. Trends in video game console energy use.
3.2.4 Computers
The AEC of portable computers has remained fairly unchanged since 2013, as increases to the installed
base have been offset by reductions in unit energy consumption (Figure 3-9). Meanwhile, estimates for
desktop AEC have increased, even as their numbers have declined, mainly due to revised usage by mode
estimates and refinements to the modeling procedure. Portable computers now significantly outnumber
desktops, which have continued to decline. Power draw by mode estimates remained largely unchanged
for desktops, while the active-mode power draw for portables has fallen by nearly a factor of two.
147
227
2006 '08 '10 '12 '14 '16
UNITS
(millions)
132
189
112
2006 '08 '10 '12 '14 '16
UEC
(kWh/yr)
19
32
25
2006 '08 '10 '12 '14 '16
AEC
(TWh)
64
128
105
1995 '99 '06 '10 '13 '17
UNITS
(millions)
24
135
79
1995 '99 '06 '10 '13 '17
UEC
(kWh/yr)
1.5
16
8.3
1995 '99 '06 '10 '13 '17
AEC
(TWh)
Fraunhofer USA Center for Sustainable Energy Systems 18
Figure 3-9. Trends in energy use estimates for computers.
3.2.5 Monitors
Even as the number of desktops declined, the number of monitors remained about the same as in 2013.
This is mainly because the number of portables increased, while the portion of portables with external
monitors remained constant. Overall, the power draw characteristics of the installed base have not
changed significantly from 2013, with power draw decreasing slightly in all modes. Most monitors are now
LCDs (over 80%). Energy use and UEC remained flat, even as the average screen size continues to increase.
Figure 3-10. Trends in energy use estimates for monitors.
3.2.6 Network Devices
Estimates for network device energy use have changed since 2013, mainly due to the shift towards
integrated access devices and away from broadband modems and local network equipment. Reports from
the industry’s voluntary agreement provided sales-weighted unit energy consumption data, whereas prior
studies were based on unweighted power draw averages. Consequently, it possible that the prior UEC
estimates were too low. Similarly, prior estimates likely overestimated the number of gateways.
Figure 3-11. Trends in energy use estimates for network devices.
5
72
16
122
2000 '05 '10 '13 '17
UNITS
(millions)
49
246
9
41
2000 '05 '10 '13 '17
UEC
(kWh/yr)
3
18
0.1
5
2000 '05 '10 '13 '17
AEC
(TWh)
Desktops
Portables
89
101
2005 '10 '13 '17
UNITS
(millions) 101
80
2005 '10 '13 '17
UEC
(kWh/yr)
98
2005 '10 '13 '17
AEC
(TWh)
32
93
15
39
2005 '08 '10 '13 '17
UNITS
(millions)
102
53 52
2005 '08 '10 '13 '17
UEC
(kWh/yr)
3
10
0.8
2
2005 '08 '10 '13 '17
AEC (TWh)
Broadband Modem +
Integrated Access
Device
Local Network Equip.
Fraunhofer USA Center for Sustainable Energy Systems 19
3.3 Uncertainty Analysis
Uncertainty in the AEC estimates for individual categories studied in depth was typically about ±15%.
Conservatively assuming that all category estimates were actually within ±20% (±50% for those studied in
less depth), we find a 90% confidence interval on the total AEC of about ±6%. This assumes all the
estimates are unbiased and that errors are independent and uniformly distributed. We recognize this is a
bold assumption that could be refined supported by additional data from future research. Thus, we
estimate that in 2017, the consumer electronic devices studied consumed 143±9 TWh.
3.4 Future Research
Based on the uncertainty analyses for specific categories, we identified several key areas that could
benefit from additional study or refinements in future work.
Connected standby modes are becoming more common among devices, notably for televisions,
soundbars, and video game consoles, and their enable-rates are not well understood. These modes can
contribute strongly to energy consumption as they draw power all the time, potentially negating some of
the reductions in passive standby power over the years. Since it can be hard to tell if these modes are
enabled or not, survey questions about connected standby modes carry greater uncertainty. Field studies
or guided surveys could help to better characterize these modes.
Real-world power draw can differ appreciably from values obtained through standardized testing
procedures. This is especially important for devices like computers, video game consoles, and televisions,
whose power can fluctuate depending on how the device is being used and what content is being
displayed. Several studies have developed multipliers to translate as-tested values to more-representative
real-world values (Xergy 2016, FhCSE 2013), however, these were based on small samples of devices and
limited real-world conditions. Further field research that studied more devices under a wider range of
conditions could better quantify these factors and may yield insights for updating the relevant test
procedures.
Devices that can be modified after purchase, such as computers, could add uncertainty to the estimates.
Gaming computers, and in particular those built or modified by enthusiasts, represent a potential area of
additional energy use. Both their usage patterns and components could lead to increased power draw
across all modes relative to typical computers (Mills and Mills 2015, Mills et al. 2017). Additional field
measurements and surveys could provide further insights.
User settings also play a strong role in some categories. Notably, television and monitor power draw could
be strongly influenced by users’ brightness settings. Power measurements for this study were typically
based on default- or as-tested values, which may not reflect the typical user settings. Similarly, automatic
power down (APD) features for devices like computers and video game consoles have a strong influence
on the time spent in different modes. Since users may be unaware of these settings, identifying APD
enable-rates with surveys carries significant uncertainty. Future studies could use alternative approaches
to improve these estimates, for instance using software or guided surveys to explicitly identify specific
power management settings.
In all categories that relied on survey data, the installed base and usage estimates carried moderate
uncertainty (±5-10%) due to sampling error. This led to higher uncertainty for categories with lower
ownership or less frequent usage (e.g., video game consoles). Increasing sample size could improve these
estimates. Additional refinements to the surveys could also address potential bias introduced by seasonal
or time-of-day effects that could influence usage. Targeted efforts to validate or calibrate sources of self-
report bias could further improve estimates, especially those pertaining to usage and behavior.
As consumer behaviors and technology continue to change rapidly, the importance of well-executed
sensor-based field monitoring campaigns cannot be understated. Using sensors in the home to non-
Fraunhofer USA Center for Sustainable Energy Systems 20
intrusively monitor device-level power draw and occupant behavior in a statistically significant and
demographically representative sample of homes remains a powerful tool for understanding how devices
are used and how they consume energy. Studies may eventually be able to leverage the data collection
and sensing capabilities of some consumer electronics themselves to provide aggregated insights about
user behaviors and time spent in various power modes. Findings from these studies could be used to
validate, complement, or improve upon the survey based tools employed in this effort, and to ensure that
product test procedures accurately reflect real-world energy performance.
3.5 References
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Equipment in Commercial Buildings - Volume I: Energy Consumption Baseline. Arthur D. Little, Inc. Report to
DOE/Office of Building Equipment. Jan.
CTA. (2016a). 18th Annual CT Ownership and Market Potential Study. Consumer Technology Association. Mar.
CTA. (2016b). U.S. CT Sales & Forecasts 2012-2017. Consumer Technology Association. Jul.
CTA. (2107a). 19th Annual CT Ownership and Market Potential Study. Consumer Technology Association. Apr.
CTA. (2107b). U.S. CT Sales & Forecasts 2013-2018. Consumer Technology Association. Jul.
DOE/EIA. (2017). Electric Power Monthly: Table 5.1. Retail Sales of Electricity to Ultimate Customers. U.S.
Department of Energy, Energy Information Administration.
Ecos. Meister, B.C., C. Scruton, V. Lew, L. ten Hope and M. Jones. (2011). Office Plug Load Field Monitoring Report.
Ecos Consulting Report to the California Energy Commission. Apr. http://www.energy.ca.gov/
2011publications/CEC-500-2011-010/CEC-500-2011-010.pdf.
FhCSE. (2013). Roth, K., S. Patel, and J. Perkinson. The Impact of Internet Browsers on Computer Energy
Consumption. Jun.
FhCSE. Urban, B., V. Shmakova, B. Lim, and K. Roth. (2014). Energy Consumption of Consumer Electronics in U.S.
Homes in 2013. Fraunhofer Center for Sustainable Energy Systems Report to the Consumer Electronics
Association. (Revised Mar. 2015). https://www.cta.tech/cta/media/News/Energy-Consumption-of-CE-in-U-S-
Homes-in-2013-(Fraunhofer,-commissioned-by-CEA,-Revised-March-2015).pdf.
FhCSE. Urban, B., V. Tiefenbeck, and K. Roth. (2011). Energy Consumption of Consumer Electronics in U.S. Homes
in 2010. Fraunhofer Center for Sustainable Energy Systems Report to the Consumer Electronics Association. Dec.
FhCSE. Urban, B., V. Tiefenbeck, and K. Roth. (2011). Energy Consumption of Consumer Electronics in U.S. Homes
in 2010. Fraunhofer Center for Sustainable Energy Systems Report to the Consumer Electronics Association. Dec.
LBNL. Kawamoto, K., J. Koomey, B. Nordman, R. Brown, M.A. Piette, M. Ting, and A. Meier. (2001). “Electricity used
by office equipment and network equipment in the U.S.: Detailed report and appendices.” Report LBNL-45917.
Lawrence Berkeley National Laboratory. Feb.
Mills, E., N. Bourassa, L. Rainer, J. Mai, L-B. Desroches, A. Shehabi, T. Pollack, and N. Mills. (2017). “An energy-
focused profile of the video game marketplace.” Gaming Systems Market Utilization and Characterization
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Mills, N. and E. Mills. (2015). Taming the energy use of gaming computers. Energy Efficiency. 8 (3) 2015.
TIAX. Roth, K. and K. McKenney. (2007). Energy Consumption by Consumer Electronics (CE) in U.S. Residences.
TIAX, LLC Report to the Consumer Electronics Association. Dec.
TIAX. Roth, K., K. McKenney, R. Ponoum, and C. Paetsch. (2008). Residential Miscellaneous Electric Loads: Energy
Consumption Characterization and Savings Potential in 2006 and Scenario-based Projections for 2020. TIAX, LLC
Report to the U.S. Department of Energy.
TIAX. Roth, K., R. Ponoum, F. Goldstein. (2006). U.S. residential information technology energy consumption in
2005 and 2010. TIAX, LLC Report to the U.S. Department of Energy, Building Technology Program. Mar.
Xergy. Dayem, K., P. May-Ostendorp, and C. Mercier. (2016). Computers – Determining a Real-World Adjustment
Factor for Computer Energy Use: Laboratory Testing the Impact of Real-World Idle, Active Mode and
Peripherals. Xergy Consulting Report Submitted by the California Investor Owned Utilities to the California
Energy Commission. Jun. http://docketpublic.energy.ca.gov/PublicDocuments/14-AAER-02/TN211731
_20160606T163325_California_Investor_Owned_Utilities_Comments_California_Investo.pdf
Fraunhofer USA Center for Sustainable Energy Systems 21
4 COMPUTERS
Personal computers include both desktops and portables. Desktops include those housed in a box or
tower with an external monitor (henceforth called Towers), and those with built-in monitors called
integrated desktops or All-in-Ones (AIO). Portables include laptops, notebooks, and netbooks, but exclude
mini and yoga notebooks (displays smaller than 10 inches) and mobile devices such as smart phones and
tablets. Those smaller devices typically draw less power and are counted separately in Section 11.
4.1 Installed Base
Installed desktops have declined to 72 million units, down 18% from 2013 (FhCSE 2014). Although the
portion of homes with at least one desktop in service remains essentially unchanged from 2013, the
number per owner-household has decreased (Table 4-1). Installed portables, meanwhile, have increased
to about 122 million units, up 31% from 2013 (FhCSE 2014). This quantity is equal to almost all portable
units sold through consumer sales channels from 2012-2016 (CTA 2016). The increase in portables was
driven mainly by increased household penetration estimates (60% vs 45% since 2013, FhCSE 2014).
Ownership estimates were higher than the installed estimates by about 18% for desktops and 40% for
portables, meaning a considerable portion of devices are not in regular use (Table 4-1, CTA 2017).
Table 4-1. Installed base estimates for computers.
COMPUTER YEAR BASE
HOUSEHOLD
PENETRATION
OWNER-HH
(millions)
UNITS per
OWNER-HH
UNITS
(millions)
SOURCE
DESKTOP
2017
Plugged In
45%
53
1.3
72
Current
2017
Owned
51%
61
1.4
85
CTA O&M (2017)
2015
In Use
42%
49
1.2
58
DOE/EIA (2017)
2013
Plugged In
44%
53
1.7
88
FhCSE (2014)
PORTABLE
2017
Plugged In
60%
72
1.7
122
Current
2017
Owned
69%
82
2.1
172
CTA O&M (2017)
2015
In Use
64%
75
1.5
116
DOE/EIA (2017)
2013
Plugged In
45%
53
1.7
93
FhCSE (2014)
To model usage by computer type, computers in the CE Usage Survey were designated by their usage
priority, with respondents answering questions about their most used (primary) and second most used
(secondary) desktop and portable computers (Table 4-2). We classified desktops without an external
monitor as All-in-One units, and assumed that the AIO portion of tertiary (and higher) desktops equaled
the portion of primary and secondary desktops that were AIOs (34%). We validated the AIO installed base
estimate against unit sales data from the previous seven years.3 Assuming most AIOs were sold to
consumers and that the U.S. accounts for 90% of North America sales, we summed unit sales data (IHA
Markit 2017, DisplaySearch 2011-2013) to obtain an All-in-One installed base of 22 million, about the
same as the CE Usage Survey estimate.
Table 4-2. Installed base (millions) for computers.
COMPUTER
FIRST
SECOND
THIRD+
TOTAL
SE
Tower
39
7
5
50
-
All-in-One
15
4
2
22
-
DESKTOP
54
11
7
72
7
PORTABLE
71
29
22
122
10
TOTAL
125
40
29
194
13
Source: CE Usage Survey. SE = standard error of the total.
3 The average lifetime of a desktop computer is likely about seven years, based on consumer channel desktop sales including AIOs that totaled
66 million units from 2010-2016 (CEA 2103b, CTA 2017) and the current installed base estimate of 72 million desktop PCs.
Fraunhofer USA Center for Sustainable Energy Systems 22
4.2 Unit Energy Consumption
4.2.1 Power Draw
We analyzed power modes similar to those defined in the ENERGY STAR requirements for computers
(v6.0, EPA 2013):
HIGH-ACTIVE In use (or idle for a short while and awaiting user input); not in a low power mode.
SHORT IDLE Idle for at least 5 min. and in a low-power mode with the screen still on.
LONG IDLE Idle for at least 15 min. and in a low-power mode with the screen off.
SLEEP Sleep mode (entered manually, or automatically after about 30 min.) from which
the computer can quickly wake.
OFF/HIBERNATE Powered down but still plugged in. Hibernate is able to resume the prior session.
Using ENERGY STAR datasets, we developed separate power draw estimates for computers that met or
did not meet the standards (Table 4-3). In all cases, we excluded computers identified as mini and business
workstations from the analysis. Market penetration of ENERGY STAR computers, ranged from 25-44% for
desktops and 74-98% for portables (Table 4-4). Power draw data for about 2,000 ENERGY STAR qualified
models from 2013-2017 shows that long- and short-idle mode power did not vary much by year among
qualified models (Figure 4-1). Non-qualified models drew about twice as much power in these modes. All-
in-One and portable computers had more pronounced differences between short- and long-idle modes,
presumably due to their integrated displays.
Table 4-3. Average power draw by mode (W) by ENERGY STAR status and year for computers.
ENERGY
ENERGY STAR MEASUREMENTS
ADJ. VALUES (REAL-WORLD)
COMPUTER
STAR
QUALIFIED?
YEAR OFF SLEEP
LONG
IDLE
SHORT
IDLE
LONG
IDLE
SHORT
IDLE
HIGH-
ACTIVE
DESKTOP
YES
2016
0.6
1.5
27
29
28
30
44
Tower
YES
2015
0.6
1.7
25
26
26
28
40
YES
2014
0.7
1.5
26
27
26
29
42
YES
2013
0.5
1.5
29
31
30
33
47
NO
2013-2016
1.2
2.5
68
71
70
75
108
DESKTOP
YES
2016
0.7
1.9
17
33
23
39
44
All-in-One
YES
2015
0.6
1.9
18
34
24
40
45
YES
2014
0.7
1.8
18
33
25
39
44
YES
2013
0.7
2.0
19
34
26
40
45
NO
2013-2016
0.9
2.1
38
68
51
79
90
PORTABLE
YES
2016
0.3
0.7
5.4
8.6
8.1
9.5
18
YES
2015
0.3
0.8
5.3
8.3
7.9
9.2
17
YES
2014
0.3
0.7
5.6
8.8
8.4
9.8
19
YES
2013
0.2
0.6
6.2
9.6
9.3
11
20
NO
2013-2016
0.5
1.1
13
19
19
21
40
Table 4-4. ENERGY STAR market share for desktop computers.
YEAR
DESKTOP
PORTABLE
2016p
44%
98%
2015
39%
95%
2014
34%
93%
2013
25%
74%
Source: EPA (2012-2015)
Note: Projection for 2016p assumes absolute pct. growth in
ENERGY STAR market share from 2015-2016 was the
same as 2014-2015.
Fraunhofer USA Center for Sustainable Energy Systems 23
Figure 4-1. Power draw of ENERGY STAR qualified desktop and portable computers available from 2013-2017.
Source: EPA (2017)
Real-world computer power draw can differ from as-tested values. Increased processing, driven by
frequently-run programs, such as web browsers, email applications, word processing, and media players,
could increase power draw levels relative to the ENERGY STAR test conditions (Xergy 2016). To account
for these differences we developed adjustment factors for the idle and active modes (Table 4-5). Given
the small number of units tested and the range of potential conditions, the real-world adjustment factors
and, hence, power draw values in the active and long-idle modes have large uncertainties.
Table 4-5. Real-world power draw adjustment factors (F) for computers.
REAL-WORLD POWER (W) by MODE
DESKTOP
PORTABLE
TOWER
AIO
High Active
= F · Short Idle ENERGY STAR
1.5
1.3
2.1
Short Idle
= F · Short Idle ENERGY STAR
1.07
1.2
1.1
Long Idle
= F · Long Idle ENERGY STAR
1.03
1.3
1.5
Source: Based on Xergy (2016) and FhCSE (2013)
Note: Very small samples (n<5), factors should be considered preliminary.
Measurements on three tower desktops, two All-in-Ones, and three notebooks (Xergy 2016) showed that
more processing-intensive activities including streaming video (see also FhCSE 2013), on-line gaming, virus
scans, video chat, and, to a lesser extent, streaming audio, could increase active-mode power draw
beyond as-tested short-idle power draw values. Desktop factors ranged from 1.2-1.6 for active mode, and
1.0-1.3 for short and long-idle modes. Another study of four desktops that measured web browser
influence on power draw found similar average factors (FhCSE 2013). In that study, the average power
draw for the most computationally intensive baseline was 1.5 times higher than the short-idle baseline,
and the real-world to short-idle ratio was 1.04 with a single browser open to a single web page at a time.4
Similarly, test results for three notebooks (Xergy 2016) found real-world adjustment factors that varied
by more than a factor of two for active (1.5 to 3.5) and long idle (1.0 to 2.2). Earlier testing of six notebooks
(FhCSE 2013) yielded a similar 1.1 ratio for real-world-short-idle to short idle, and a 1.9 factor for active-
to-short-idle testing under a more limited range of conditions than Xergy (2016) that were generally
similar to high-active mode.5 Consequently, we used the average values from these two studies, 2.1 and
1.1, for real-world high-active and real-world-short-idle ratios to the ENERGY STAR short-idle values.
4 Power draw was measured after loading the default home page for ten popular websites individually on three different browsers.
5 FhCSE (2013) measured the power draw of six notebook PCs while separately running the Fishbowl benchmark and a computer animated film
in Flash and then HTML5, in three different browsers. The 1.9 real-world factors equal the average ratio of testing under all those conditions
relative to the short idle baseline testing without a browser or other windows open, and anti-virus disabled.
0
20
40
60
80
SHORT IDLE
LONG IDLE
SLEEP
OFF
W
PORTABLE
ALL-IN-ONE
DESKTOP
Fraunhofer USA Center for Sustainable Energy Systems 24
To calculate power draw for ENERGY STAR qualified computers, we took the straight average (by mode,
computer type, and year of release) of all models listed in the ENERGY STAR database as of February 2017
(EPA 2017) and multiplied them by the real-world adjustment factors summarized above. To calculate
power draw for non-ENERGY STAR qualified computers, we used the dataset that was used to develop
the ENERGY STAR v6.0 specification (EPA 2012). Specifically, we identified all models in the dataset that
did not meet the v6.0 specification for any mode, and we assumed that those computers were
representative of non-ENERGY STAR tower desktops sold from 2013-2016.
Next, we weighted the power draw for all computers by type and year sold according the ENERGY STAR
qualified market share. Assuming all tower desktops sold from 2013-2016 remained in service, a majority
(26 of 47 million units) would have entered service before 2013 (CTA 2017, CEA 2013). We used the tower
desktop power draw values from the 2013 study to represent pre-2013 computers (FhCSE 2014), again
applying the adjustment factors. Finally, we calculated the sales-weighted average power draw by mode
across the entire installed base (Table 4-6).
Table 4-6. Power draw by mode (W) for the installed base of desktop and portable computers.
REAL-WORLD ADJUSTED
COMPUTER YEAR
UNITS
(millions)
OFF SLEEP
IDLE-
LONG
IDLE-
SHORT
HIGH-
ACTIVE
DESKTOP
2016
3.9
0.9
2.1
52
56
80
Tower
2015
4.8
1.0
2.2
53
57
82
2014
5.9
1.0
2.2
55
60
86
2013
6.5
1.0
2.3
60
65
93
Pre-2013
26.0
1.6
3.5
58
61
87
Wtd. Avg.
1.3
2.9
57
60
87
DESKTOP
2016
2.9
0.8
2.0
38
62
70
All-in-One
2015
3.3
0.8
2.0
40
64
72
2014
3.8
0.8
2.0
42
66
74
2013
3.3
0.9
2.1
45
69
78
Pre-2013
10.7
1.4
2.7
57