Energy Conservation Standards Rulemaking Framework for 

Computer and Battery Backup Systems

U.S. Department of Energy

Office of Energy Efficiency and Renewable Energy

Building Technologies Office

July 9, 2014
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TABLE OF CONTENTS

1. Introduction............................................................................................................................ 1

1.1 Authority and Background.................................................................................................. 1

1.2 Energy Savings Opportunity............................................................................................... 3

1.2.1 Energy Consumption of Computers................................................................................. 3

1.2.2 Energy Consumption of Computer Servers..................................................................... 6

1.2.3 Energy Consumption of Uninterruptible Power Supplies ............................................... 6

1.2.4 Technology Options for Improved Efficiency................................................................. 7

2. Overview of the Rulemaking Process.................................................................................... 7

2.1 Test Procedures................................................................................................................... 7

2.2 Energy Conservation Standards.......................................................................................... 7

2.2.1 Preliminary Analysis........................................................................................................ 9

2.2.2 Notice of Proposed Rulemaking .................................................................................... 10

2.2.3 Final Rule ..................................................................................................................... 11

2.2.4 Overview of Analyses for Rulemaking.......................................................................... 12

3. Scope of Coverage ............................................................................................................... 14

3.1 Definition of Computers................................................................................................... 14

3.2 Definition of Computer Servers........................................................................................ 15

3.3 Definition of Uninterruptible Power Supplies.................................................................. 16

3.4 Scope of Computer Systems Test Procedure and Standards Rulemakings ...................... 16

3.4.1 Computers ..................................................................................................................... 17

3.4.2 Computer Servers........................................................................................................... 19

3.4.3 Uninterruptible Power Supplies..................................................................................... 21

4. Test Procedures.................................................................................................................... 23

4.1 Methods of Measurement for Computers......................................................................... 23

4.1.1 Existing Industry and Regulatory Test Procedures........................................................ 23

4.1.2 Proposed DOE Test Method for Computers.................................................................. 24

4.1.3 Annual Energy Consumption Metric ............................................................................. 25

4.1.4 Annual Energy Consumption Metric for Computers with a Network Proxy ................ 26

4.2 Methods of Measurement for Computer Servers.............................................................. 27

4.2.1 Existing Regulatory and Voluntary Test Procedures..................................................... 27

4.2.2 Proposed DOE Test Method for Computer Servers ...................................................... 28

4.3 Methods of Measurement for Uninterruptible Power Supplies........................................ 30

4.3.1 Existing Industry Test Procedures................................................................................. 30

4.3.2 Proposed DOE Test Method for Uninterruptible Power Supplies................................. 31

5. Product Classes.................................................................................................................... 31

5.1 Computer Product Classes................................................................................................ 32

5.1.1 Existing Voluntary and Regulatory Standards............................................................... 32

5.1.2 ENERGY STAR Computers V. 5.2 Product Overview ................................................ 32

5.1.3 ENERGY STAR Computers V. 6.0............................................................................... 35

5.2 Computer Server Product Classes..................................................................................... 37

5.3 Uninterruptible Power Supplies Product Classes ............................................................. 38

6. Market and Technology Assessment ................................................................................... 40

6.1 Market Assessment ........................................................................................................... 40
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6.1.1 Market Assessment for Computers................................................................................ 41

6.1.2 Market Assessment for Computer Servers .................................................................... 41

6.1.3 Market Assessment for Uninterruptible Power Supplies............................................... 42

6.2 Technology Assessment for Computers ........................................................................... 43

6.2.1 Efficient Power Supplies................................................................................................ 44

6.2.2 Efficient Hard Drives..................................................................................................... 44

6.2.3 Energy-Efficient Ethernet .............................................................................................. 45

6.2.4 Passive Cooling.............................................................................................................. 45

6.2.5 ACPI-Compatible Devices............................................................................................. 45

6.2.6 Switchable Graphics ...................................................................................................... 45

6.2.7 Dynamic Voltage and Frequency Scaling...................................................................... 46

6.2.8 Resilient Circuitry.......................................................................................................... 46

6.2.9 Clock Gating .................................................................................................................. 46

6.2.10 CPU Utilization Management........................................................................................ 47

6.2.11 Suspended State to Flash ............................................................................................... 47

6.2.12 Internal Network Proxy.................................................................................................. 47

6.3 Technology Assessment for Computer Servers................................................................ 47

6.3.1 Fan Speed Control Algorithms ...................................................................................... 48

6.3.2 Management Interface Low-Power States..................................................................... 48

6.4 Technology Assessment for Uninterruptible Power Supplies.......................................... 48

6.4.1 Semiconductor Improvements....................................................................................... 48

6.4.2 Digital Signal Processing and Space Vector Modulation.............................................. 49

6.4.3 Transformer-less UPS Topologies................................................................................. 49

7. Screening Analysis............................................................................................................... 49

8. Engineering Analysis........................................................................................................... 50

8.1 Engineering Analysis Overview ....................................................................................... 51

8.2 Engineering Analysis Methodology ................................................................................. 52

8.2.1 Representative Units and Baseline Models.................................................................... 52

8.3 Proprietary Designs........................................................................................................... 53

8.4 Efficiency Levels.............................................................................................................. 53

8.5 Outside Regulatory Changes Affecting the Engineering Analysis................................... 54

9. Markups Analysis ................................................................................................................ 54

10. Energy Use Analysis............................................................................................................ 55

11. Life-Cycle Cost and Payback Period Analyses ................................................................... 56

11.1 Approach........................................................................................................................... 56

11.2 Electricity Prices............................................................................................................... 58

11.3 Maintenance, Repair, and Installation Costs..................................................................... 59

11.4 Product Lifetimes.............................................................................................................. 59

11.5 Discount Rates.................................................................................................................. 59

11.6 Energy Efficiency in the Base Case.................................................................................. 60

12. Shipments Analysis.............................................................................................................. 61

12.1 Base-Case Forecast ........................................................................................................... 61

12.2 Impact of Standards on Product Shipments...................................................................... 61

13. National Impact Analysis..................................................................................................... 62

13.1 Energy Efficiency Trends................................................................................................. 62

13.2 National Energy Savings................................................................................................... 63
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13.3 Net Present Value ............................................................................................................. 63

14. Consumer Subgroup Analysis.............................................................................................. 64

15. Manufacturer Impact Analysis............................................................................................. 64

15.1 Sources of Information for the Manufacturer Impact Analysis........................................ 65

15.2 Industry Cash Flow Analysis............................................................................................ 65

15.3 Manufacturer Subgroup Analysis..................................................................................... 66

15.4 Competitive Impacts Assessment ..................................................................................... 66

15.5 Cumulative Regulatory Burden ........................................................................................ 67

16. Emissions Analysis.............................................................................................................. 67

17. Monetizing Reduced Carbon Dioxide and other Emissions................................................ 69

18. Utlity Impact Analysis......................................................................................................... 70

19. Employment Impact Analysis.............................................................................................. 71

20. Regulatory Impact Analysis................................................................................................. 72

Appendix A. Scope of Industry Standards................................................................................ 73

Appendix B. List of Items for Comment.................................................................................. 76
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LIST OF FIGURES

Figure 1-1: Histogram showing Normalized Energy Consumption of ENERGY STAR Qualified 

Desktop Computers after January 1, 2012...................................................................................... 4

Figure 1-2: Histogram showing Normalized Energy Consumption of ENERGY STAR Qualified 

Integrated Desktop Computers after January 1, 2012..................................................................... 5

Figure 1-3: Histogram showing Normalized Energy Consumption of ENERGY STAR Qualified 

Notebooks after January 1, 2012 .................................................................................................... 5

Figure 2-1: Flow Diagram of Analyses for a Traditional Standards Rulemaking Process........... 13

Figure 6-1: Current and Projected Device Shipments by Year..................................................... 41

Figure 6-2: Worldwide Quarterly Server Shipments (3Q12 to 3Q13) ......................................... 42

Figure 6-3: World UPS Market Development.............................................................................. 43

LIST OF TABLES

Table 1-1: Estimated U.S. Energy Use of Computer Servers in 2010............................................ 6

Table 4-1: ENERGY STAR Computers V. 6.0 Modal Weightings, based on ECMA-383 Ed. 3 25

Table 4-2: ENERGY STAR Computers V. 6.0 Modal Weightings with Proxy for Desktop, 

Integrated Desktop, and Thin Client Computers.......................................................................... 26

Table 4-3: ENERGY STAR Computers V. 6.0 Modal Weightings with Proxy for Notebook 

Computers..................................................................................................................................... 26

Table 5-1: ENERGY STAR Computers V. 5.2 Categories for Desktop, Integrated Desktop, and 

Notebook Computers.................................................................................................................... 33

Table 5-2: ENERGY STAR Computers V. 5.2 Allowance Classification................................... 34

Table 5-3: ENERGY STAR Computers V. 5.2 Categories for Small-scale Servers and Thin 

Clients........................................................................................................................................... 35

Table 5-4: ENERGY STAR Computers V. 6.0 Base Categories for Desktop and Integrated 

Desktop Computers....................................................................................................................... 36

Table 5-5: ENERGY STAR Computers V. 6.0 Base Categories for Notebook Computers........ 36

Table 5-6: ENERGY STAR Computers V. 6.0 Discrete Graphics Allowance ............................ 36

Table 5-7: ENERGY STAR Computer Servers V. 2.0 Categories............................................... 38

Table 5-8: ENERGY STAR UPS V. 1.0 Efficiency Levels for AC-Output UPS........................ 39

Table 5-9: ENERGY STAR UPS V. 1.0 Efficiency Levels for DC-Output UPS........................ 40

Table A-1: ENERGY STAR Computers V. 5.2 Scope of Coverage............................................ 73

Table A-2: Scope Updates in ENERGY STAR Computers V. 6.0 from V. 5.2........................... 73

Table A-3: Differences in Scope of Coverage for Regulatory Programs..................................... 74

Table A-4: ENERYGY STAR Computer Servers V. 2.0 Scope of Coverage ............................. 74
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LIST OF ACRONYMS AND ABBREVIATIONS

AC alternating current

ACEEE American Council for an Energy-Efficient Economy

ACPI Advanced Configuration and Power Interface

AEC annual energy consumption

AEDM alternate efficiency determination method

AEO Annual Energy Outlook

AMD Advanced Micro Devices

APPA American Public Power Association

ASAP The Appliance Standards Awareness Project

AS/NZS Australian/New Zealand standard

BIOS basic input/output system

BOM bill of materials

BTO Building Technologies Office

BOB buffered on board

BW bandwidth

CEA Consumer Electronics Association

CFR Code of Federal Regulations

CPU central processing unit

CSAPR Cross-State Air Pollution Rule

CSL candidate standard level

DC direct current

DIMMs dual in-line memory modules 

DOE U.S. Department of Energy

DOJ U.S. Department of Justice

DSP digital signal processing

DVD digital video disc

DVR digital video recorder

ECC error-correcting code

EEE Energy-Efficient Ethernet

EEI Edison Electric Institute

EERE Office of Energy Efficiency and Renewable Energy

EGU electric generating units

EIA Energy Information Administration

EMI electromagnetic interference

EPA U.S. Environmental Protection Agency

EPCA Energy Policy and Conservation Act

EU European Union

FFC full fuel cycle

FOIA Freedom of Information Act
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FR Federal Register

GB gigabyte

GHG greenhouse gas

GPU graphics processing unit

GREET Greenhouse Gases, Regulated Emissions, and Energy Use in 

Transportation

GRIM government regulatory impact model

HAP hazardous air pollutants

HDD hard disk drive

IBM International Business Machines Corporation

IDC International Data Corporation

IEC International Electrotechnical Commission

IEEE Institute of Electrical and Electronics Engineers

IGBT insulated gate bipolar transistors

ImSET Impact of Sector Energy Technologies

ITI Information Technology Industry Council

kWh kilo-watt hours

LBNL Lawrence-Berkeley National Laboratory

LCC life-cycle cost

MATS Mercury and Air Toxics Standards

MIA manufacturer impact analysis

MSP manufacturer selling price

NCI Navigant Consulting, Inc.

NEEA Northwest Energy Efficiency Alliance

NEEP Northeast Energy Efficiency Partnerships

NEMA The National Electrical Manufacturers Association

NEMS National Energy Modeling System

NES national energy savings

NIA national impact analysis

NOPD notice of proposed determination

NOPR notice of proposed rulemaking

NPV net present value

NRDC Natural Resources Defense Council

OMB U.S. Office of Management and Budget

OS operating system

PBP payback period

PDA personal digital assistant

PM particulate matter

POS point of sale

PSU power supply unit

R&D research and development
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RIA regulatory impact analysis

RPM rotations per minute

SCC social cost of carbon

SCR silicon controlled rectifier

SERT Server Efficiency Rating Tool

SPEC Standard Performance Evaluation Corporation

SSD solid-state drive

SVM space vector modulation

TCO total cost of ownership

TIA Telecommunications Industry Association

TSD technical support document

TSL trial standard level

UPS uninterruptible power supply

U.S.C. United States Code

VFD voltage and frequency dependent

VFI voltage and frequency independent

VI voltage independent

WOL wake-on-LAN
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1. INTRODUCTION

The U.S. Department of Energy (DOE) Appliances and Equipment Standards Program, 

within the Office of Energy Efficiency and Renewable Energy’s Building Technologies Office

(BTO), establishes test procedures and energy conservation standards for certain consumer 

appliances and commercial and industrial equipment. The process for considering whether to 

establish standards involves analysis, public notice and comment, and consultation with 

interested parties. Interested parties include manufacturers, consumers, energy conservation and 

environmental advocates, state and federal agencies, and any other groups or individuals with an 

interest in these standards and test procedures.

The purpose of this document is to describe the procedural and analytical approaches 

DOE anticipates using to evaluate potential new energy conservation standards or energy use 

standards for computer and battery backup systems (computer systems). This framework 

document is intended to inform interested parties of the process DOE will follow for this 

standards rulemaking, and to encourage and facilitate the input of interested parties during the 

rulemaking. This document is merely the starting point for evaluating energy conservation 

standards or energy use standards and is not a definitive statement on any issue to be determined 

in the rulemaking.

Section 1 of this report includes an overview of DOE’s appliances standards program, the 

statutory authority for this rulemaking, and the energy savings opportunity through this 

rulemaking. Section 2 includes an overview of the rulemaking process. Scope of coverage and 

test procedures are described in sections 3 and 4. Sections 5 through 20 discuss the analyses 

DOE intends to conduct to fulfill the statutory requirements and guidance for this energy 

conservation standards rulemaking. DOE’s analyses will determine whether new energy 

conservation standards or energy use standards are technologically feasible, economically 

justified, and would result in significant energy savings. DOE will maintain information about 

this rulemaking on its website at: 

www1.eere.energy.gov/buildings/appliance_standards/product.aspx/productid/81. 

While DOE invites comment on all aspects of the material presented in this document, 

several specific issues on which DOE seeks comment are set out in comment boxes like this 

one. DOE uses these comment boxes to highlight issues and ask specific questions on the 

approaches DOE plans to follow to conduct the analyses required for the energy conservation 

standards rulemaking. Such requests for feedback are numbered sequentially throughout the 

document and are repeated in Appendix A.

1.1 Authority and Background

Title III of the Energy Policy and Conservation Act of 1975 (EPCA) sets forth a variety 

of provisions designed to improve the energy efficiency of various products and equipment. 
2

Part B of Title III (42 U.S.C. 6291–6309) established the “Energy Conservation Program for 

Consumer Products Other Than Automobiles,” which covers consumer products and certain 

commercial equipment (hereafter referred to as “covered products”).1In addition to specifying a 

list of covered residential and commercial products, EPCA contains provisions that enable the 

Secretary of Energy (Secretary) to classify additional types of consumer products as covered 

products. (42 U.S.C. 6292(a)(20)) For a given product to be classified as a covered product, the 

Secretary must determine that:

(1) Classifying products of such type as covered products is necessary or appropriate to 

carry out the purposes of EPCA, and

(2) Average annual per-household energy use by products of such type is likely to 

exceed 100 kilowatt-hours (kWh) per year. (42 U.S.C. 6292(b)(1))

Under this authority, DOE published a notice of proposed determination (NOPD) on 

February 28, 2014 (the February 2014 NOPD) that tentatively determined that computer systems

meet the criteria for a covered product because classifying products of such type as a covered 

product is necessary or appropriate to carry out the purposes of EPCA, and the average U.S. 

household energy use for computer systems is likely to exceed 100 kWh per year. 79 FR 11345.

Computers, computer systems, and uninterruptable power supplies (UPSs) are considered in the 

scope of the February 2014 NOPD.

For any product that DOE classifies as a covered product, it may prescribe test 

procedures. (42 U.S.C. 6293(b)) EPCA also specifies that the Secretary may prescribe an energy 

conservation standard pursuant to 42 U.S.C. 6295(o) and (p) for covered products added 

pursuant to 42 U.S.C. 6292(b)(1), if the Secretary determines that:

(1) The average household energy use of the products has exceeded 150 kWh per 

household for a 12-month period;

(2) The aggregate 12-month energy use of the products has exceeded 4.2 billion kWh;

(3) Substantial improvement in energy efficiency is technologically feasible; and

(4) The application of a labeling rule under 42 U.S.C. 6294 is unlikely to be sufficient 

to induce manufacturers to produce, and consumers and other persons to purchase, 

covered products of such type (or class) which achieve the maximum energy 

efficiency which is technologically feasible and economically justified. (42 U.S.C. 

6295(l)(1))

Because DOE has tentatively determined that computer systems are a covered product

and meet the statutory thresholds for setting energy conservation standards, DOE is undertaking 

this rulemaking process, including the publication of this framework document, to meet the 

 

1

Part B was re-designated Part A on codification in the U.S. Code for editorial reasons.
3

above described EPCA requirements. This framework document and the associated public 

meeting represent the first step in the rulemaking process to consider whether to establish a test 

procedure and energy conservation standard for computer systems. DOE recognizes that 

different test methods and efficiency metrics would be necessary to measure the energy 

consumption and energy efficiency of different product types such as computers, computer 

servers, and UPSs. Therefore, DOE is considering different test procedures for computers, 

servers, and UPSs as discussed in section 3 of this framework document. Additionally, for the

efficiency standards rulemaking, product classes may be established based on the type of energy 

used, the capacity, and any other performance-related feature that justifies different standard 

levels, such as features affecting consumer utility. (42 U.S.C. 6295(q))

1.2 Energy Savings Opportunity

DOE analyzed energy consumption data for computers, computer servers, and UPSs to 

evaluate their energy saving opportunities. This investigation explored the total energy 

consumption for each product as well as the range in energy consumption between comparable 

products. 

1.2.1 Energy Consumption of Computers

In June 2014, the Consumer Electronics Association (CEA) published a study that 

quantifies the electricity consumption of consumer electronics in US households in 2013.2

Among other products, the study evaluated the annual electricity consumption of desktop and 

portable computers. While the annual electricity consumption has decreased from 2010, 

according to the study, desktop computers consume 16 TWh/year and portable computers 

consumer 4.9 TWh/year. The CEA study considered the ENERGY STAR® Version 6.0 

Specification for Computers, Rev. October 2013 (ENERGY STAR Computers V. 6.0) dataset to 

represent computers sold from 2011 to 2013, and data from a previous study (Fraunhofer 2011) 

to represent older computers.

To further evaluate the energy consumption profile of computers, DOE used the

ENERGY STAR qualified product list for computers3and focused its analysis on products that 

were available on the market after January 1, 2012, because newer computers have the latest 

features in terms of functionality and energy saving options. Figure 1-1 through Figure 1-3 show 

the variation in energy consumption for desktop, integrated desktop, and notebook computers in 

each product category, as classified by ENERGY STAR Version 5.2 Specification for 

Computers, Rev. August 2010 (ENERGY STAR Computers V. 5.2).

4 DOE also normalized data 

 

2 Energy Consumption of Consumer Electronics in US Homes in 2013. Fraunhofer USA, Final Report to the 

Consumer Electronics Association. June 2014.

3 ENERGY STAR Program Requirements for Computers, Qualified Computers, September 13, 2013 

<http://downloads.energystar.gov/bi/qplist/Computers_Product_List.xls>

4 ENERGY STAR Program Requirements Product Specification for Computers: Eligibility Criteria Version 5.2 Rev. 

Aug-2010.
4

available on ENERGY STAR’s qualified product list with respect to functional energy 

allowances to ensure that the variation in energy was due solely to differences in efficiency of 

technologies, and not due to differences in additional functionality. This variation is expressed in 

box and whisker plots which show the relative maximum and minimum annual energy 

consumption as well as the median value, the 25th quartile, and the 75

th quartile. To calculate the 

normalized annual energy consumption (AEC)5, DOE used the following equation:

 

 ( )

 ( )

 

Figure 1-1: Histogram showing Normalized Energy Consumption of ENERGY STAR 

Qualified Desktop Computers after January 1, 2012

 

5 ENERGY STAR uses the term “typical energy consumption (TEC),” which is referred to as “annual energy 

consumption (AEC)” in this document to conform to DOE convention.
5

Figure 1-2: Histogram showing Normalized Energy Consumption of ENERGY STAR 

Qualified Integrated Desktop Computers after January 1, 2012

Figure 1-3: Histogram showing Normalized Energy Consumption of ENERGY STAR 

Qualified Notebooks after January 1, 2012

As seen in Figure 1-1 through Figure 1-3, the energy consumption of computers in most 

categories shows a significant variation. It is also important to note that the dataset for these 

graphs was limited to ENERGY STAR Computers V. 5.2 qualified computers only, which 

comprise only a portion of the market. DOE expects the variation in energy consumption to be 

equal or larger if the entire market is analyzed.

Based on this analysis, DOE believes there are opportunities to improve the energy 

efficiency of computers.
6

1.2.2 Energy Consumption of Computer Servers

DOE’s investigation on the energy consumed by computer servers in the U.S. was based 

on a publication by the Analytics Press, which estimated data center energy consumption from 

2005 -2010.

6

This analysis is summarized in Table 1-1 and shows a granular breakdown of 

energy usage by “cost level”. Additionally, this data is separated into high and low energy 

estimates to account for the uncertainty in the average operating power of each computer server 

type. The low estimate assumes no increase in the average per-server power consumption from 

2005 to 2010 while the high estimate assumes an annual increase of 3.3%, 8.1%, and 6.7% for 

volume servers, mid-range servers, and high-end servers respectively. 

Table 1-1: Estimated U.S. Energy Use of Computer Servers in 2010

Server Type

International Data 

Corporation Definition:

Server Cost is...

Low Estimate

(Billion kWh/year)

High Estimate

(Billion kWh/year)

Volume Less than $25,000 22.5 26.4

Mid-range $25,000 to $500,000 1.7 2.5

High-end Greater than $500,000 2.3 3.2

Total 26.5 32.1

DOE believes that due to the larger amount of energy consumed at lower price points, 

there are potential opportunities for significant energy savings with more efficient computer 

servers. 

1.2.3 Energy Consumption of Uninterruptible Power Supplies

DOE’s review of UPSs has shown an estimated national energy consumption of 8.1 

TWh/yr in 2013 of which 3.5 TWh/yr is contributed by mixed use and residential only units.7

The need to protect information technology infrastructure and the high cost of not doing so has 

pushed consumers to invest heavily in backup power.8This has contributed to the overall growth 

of the UPS market and its corresponding national energy usage. With the recent upward trend in 

cloud storage, the UPS market is expected to continue growing.9This fact leads DOE to 

recognize that this estimated total energy use is a lower limit. DOE will conduct an engineering 

 

6 Koomey, Jonathan. Growth in Data Center Electricity Use 2005-2010. Analytics Press. 2011.

7 Analysis based on data compiled from (a) ENERGY STAR UPS Program Qualified Products List, (b) Zogg, R. et 

al., 2009. Energy Savings Potential and RD&D Opportunities for Commercial Building Appliances and (c) TIAX, 

“U.S. Residential Information Technology Energy Consumption in 2005 and 2010, Final Report”. Prepared for the 

U.S. Department of Energy, Building Technologies Program, March 2006. Analysis includes only standby and lineinteractive UPSs, and assumes an average load of approximately 0.7. 

8 World Data Center UPS Market, Frost & Sullivan, December 1, 2011.

9 Meir Portnoy, Impact of Cloud Computing on UPS Market & Systems, March 2011.
7

and market analysis to understand if technologies exist to improve the efficiency of consumer 

UPSs and help reduce its energy burden.

1.2.4 Technology Options for Improved Efficiency

DOE has begun investigating technologies that may potentially improve energy 

efficiency in computers, computer servers, and UPSs. The existence of these technology options 

indicates that improvement of energy efficiency in these products is feasible and an energy 

conservation standard could fulfill the purposes of EPCA in reducing energy consumption. DOE 

will conduct a technology assessment to generate a thorough list of technology options and then 

screen out technology options that are not (1) technologically feasible; (2) practical to 

manufacture, install, and service; (3) have adverse impacts on product utility or availability; or

(4) have adverse impacts on health or safety. This is discussed in more detail in sections 6 and 7.

2. OVERVIEW OF THE RULEMAKING PROCESS

2.1 Test Procedures

Under 42 U.S.C. 6293, EPCA sets forth the criteria and procedures DOE must follow 

when prescribing or amending a test procedure for covered products. EPCA provides in relevant 

part that any test procedure prescribed or amended under this section shall be reasonably 

designed to produce test results that measure energy efficiency, energy use, or estimated annual 

operating cost of a covered product during a representative average use cycle or period of use 

and shall not be unduly burdensome to conduct. (42 U.S.C. 6293(b)(3)) If the Secretary 

determines that a test procedure should be prescribed for a covered product, a proposed test 

procedure should be published in the Federal Register and interested persons should be provided 

an opportunity to present oral and written data, views, and arguments with respect to the 

proposed procedure. (42 U.S.C. 6293(b)(2))

DOE is considering initiating a test procedure rulemaking for computer systems because 

it has been tentatively determined that computer systems meet the criteria for a covered product 

and a test procedure will be required to determine the energy conservation standard for this 

product.

As a first step in the rulemaking process, DOE evaluates available industry test 

procedures and requests comment on specific topics in section 4 of this framework document. 

DOE will review comments received in response to today’s framework document and publish a 

notice of proposed rulemaking (NOPR) in the Federal Register as the next step in establishing a 

regulatory test procedure for computer systems. The NOPR and associated public meeting will 

provide interested parties an opportunity to provide comments on the proposed test procedure. 

Following the end of the NOPR comment period, a final rule will be published in the Federal 

Register.

2.2 Energy Conservation Standards

When DOE evaluates any new or amended energy conservation standard for covered 

products, EPCA, as amended, specifies that any standard DOE prescribes for consumer products 
8

must be designed to achieve the maximum improvement in energy efficiency that is 

technologically feasible and economically justified. (42 U.S.C. 6295(o)(2)(A)) Moreover, the 

Secretary may not establish a new or amended standard if such standard would not result in 

significant conservation of energy. (42 U.S.C. 6295(o)(3)(B)) In determining whether a standard 

is economically justified, DOE must consider, to the greatest extent practicable, the following 7 

factors:

(1) The economic impact of the standard on the manufacturers and on the consumers of 

the products subject to such standard;

(2) The savings in operating costs throughout the estimated average life of the covered 

product in the type (or class) compared to any increase in the price of, or in the 

initial charges for, or maintenance expenses of, the covered products which are 

likely to result from the imposition of the standard;

(3) The total projected amount of energy, or as applicable, water, savings likely to 

result directly from the imposition of the standard; 

(4) Any lessening of the utility or the performance of the covered products likely to 

result from the imposition of the standard;

(5) The impact of any lessening of competition, as determined in writing by the 

Attorney General, that is likely to result from the imposition of the standard;

(6) The need for national energy and water conservation; and

(7) Other factors the Secretary considers relevant. (42 U.S.C. 6295(o)(2)(B)(i)(I)-(VII))

The analyses performed to consider the above 7 factors are the focus of the energy 

conservation standard rulemaking process and are described in sections 5 through 20. The typical 

process of developing conservation standards involves analyses, public notice, and consultation 

with interested parties. Such interested parties generally include manufacturers, consumers, 

energy conservation and environmental advocates, state and federal agencies, and any other 

groups or individuals with an interest in energy conservation standards and test procedures. DOE 

considers participation of interested parties to be a very important part of the rulemaking process. 

Accordingly, DOE actively encourages the participation and interaction of all interested parties 

during the comment period provided at each stage of the rulemaking. The broad array of 

interested parties who routinely provide comments promotes a balanced discussion of critical 

information required to conduct the standards rulemaking, beginning with public comment on 

the framework document. 

In conducting the test procedure rulemakings and the energy (and water) conservation 

standards rulemakings, DOE involves interested parties through a variety of means. As discussed 

in further detail below, the standards rulemaking process involves two to three public notices in 

addition to the notice of availability of the framework document. All of these notices are 

published in the Federal Register. Publication of the framework document, preliminary analysis, 

and NOPR are typically accompanied by public meetings to solicit comment from interested 

parties to enhance the rulemaking process.
9

Briefly, these steps include:

 Preliminary analysis (section 2.2.1). The preliminary analysis presents a discussion of 

comments received on the framework document and is designed to solicit public 

feedback on the models and tools that DOE intends to use in the rulemaking. Using these 

models and tools, DOE performs preliminary analyses to assess candidate standard levels 

(CSLs), which span the range of efficiencies from baseline product to the most efficient 

technology. 

 Notice of proposed rulemaking (section 2.2.2). The NOPR presents a discussion of 

comments received in response to the preliminary analysis; DOE’s analyses of the 

impacts of potential standards on consumers, manufacturers, and the nation; DOE’s 

weighting of these impacts, and any proposed standard levels for public comment. 

 Final rule (section 2.2.3). The final rule presents a discussion of comments received in 

response to the NOPR, revised analyses, as appropriate, of the impacts of any standards, 

DOE’s weighting of those impacts, and the standard levels, if any, that DOE is adopting. 

The final rule also establishes the date by which manufacturers must comply with any 

standards. 

2.2.1 Preliminary Analysis

As part of its energy conservation standards rulemaking activity, DOE typically identifies 

product technology options and makes a preliminary determination as to whether to retain each 

option for detailed analysis or to eliminate it from further consideration. This process includes a 

market and technology assessment (section 6) and a screening analysis (section 7). DOE applies 

four screening criteria in the screening analysis to determine which technology options to 

eliminate from further consideration: (1) technological feasibility; (2) practicability to 

manufacture, install, and service; (3) adverse impacts on product utility or availability; and 

(4) adverse impacts on health or safety. Technologies that pass through the screening analysis are 

evaluated, and referred to as design options, in the engineering analysis (section 8).

DOE consults with interested parties and researches industry literature to identify the 

design options or efficiency levels that DOE will consider in the rulemaking. DOE considers 

design options or efficiency levels for each product class. DOE uses these design options or 

efficiency levels to collect manufacturer cost data, historical shipment data, shipment-weighted 

average efficiency data, and preliminary manufacturer impact data (e.g., capital conversion 

expenditures, marketing costs, and research and development (R&D) costs). As part of the 

preliminary analysis, DOE also conducts other principal analyses, including:

(1) engineering analysis (section 8);

(2) markups analysis (section 9);

(3) energy use analysis (section 10);

(4) consumer life-cycle cost (LCC) and payback period (PBP) analysis (section 11); 
10

(5) shipments analysis (section 12);

(6) national impact analysis (NIA), which considers national energy savings (NES) and 

consumer net present value (NPV) (section 13); and 

(7) preliminary manufacturer impact analysis (MIA) (section 15).

Based on the preliminary results of these analyses, DOE selects CSLs from the energy 

efficiency levels considered in the preliminary analysis. In addition to the efficiency level 

corresponding to the maximum technologically feasible (max-tech) efficiency level, DOE 

generally considers efficiency levels that span the full range of technologically achievable 

efficiencies. The range of efficiency levels that DOE typically analyzes includes:

 The baseline efficiency level, which typically represents products with the lowest energy 

efficiency on the market. For products that already have energy conservation standards, 

DOE typically defines the baseline efficiency level by the existing energy conservation 

standard.

 The highest energy efficiency level or lowest energy consumption level that is 

technologically feasible and satisfies the screening criteria (i.e., max-tech).

 Levels that incorporate noteworthy technologies or fill large gaps between other 

efficiency levels being considered.

DOE uses analytical models and tools to assess the different product classes at each 

efficiency or energy use level analyzed. Many of these analytical models and tools are in the 

form of spreadsheets, used to conduct the LCC and PBP analyses and to determine the NES and 

NPV of prospective standards. Discussion of various CSLs in the preliminary analysis helps 

interested parties review the spreadsheet models that underpin the analyses. DOE uses comments 

from interested parties to refine the models for the next stage of the rulemaking analyses.

2.2.2 Notice of Proposed Rulemaking

In developing any NOPR, DOE considers the comments received during the comment 

period of the prior phase. This process can result in revisions to the analyses conducted during 

the preliminary analysis stage; DOE conducts additional economic and environmental impact 

analyses for the NOPR. These analyses generally include:

(1) consumer LCC subgroup analysis (section 14); 

(2) complete MIA (section 15);

(3) emissions analysis (section 16); 

(4) monetization of emissions (section 17);

(5) utility impact analysis (section 18); 
11

(6) employment impact analysis (section 19); and

(7) regulatory impact analysis (RIA) (section 20).

On its website docket, DOE describes the methodology used and makes the results of all 

the analyses available for review. This analytical process results in the selection of proposed 

standard levels, if any, that DOE presents in the NOPR. DOE selects the proposed standard 

levels from the trial standard levels (TSLs) analyzed during the NOPR phase of the 

rulemaking.

10 The NOPR is published in the Federal Register and describes the evaluation and 

selection of any proposed standards levels, along with a discussion of other TSLs considered but 

not selected and the reasons DOE did not select them. For each product class, DOE identifies the 

max-tech efficiency level. If DOE proposes a lower level, DOE explains the reasons for 

eliminating higher levels, beginning with the highest level considered. DOE presents the 

analytical results in the NOPR and provides the details of the analysis in an accompanying 

technical support document (TSD). 

DOE considers many factors in selecting proposed standards. These factors are 

prescribed by EPCA and take into consideration the benefits and costs of energy conservation 

standards. 

When DOE publishes the NOPR, it provides the U.S. Department of Justice (DOJ) with 

copies of the NOPR and TSD to solicit feedback on the impact of any proposed standard levels 

on competition in the market of the product that is the subject of the rulemaking. DOJ reviews 

standard levels to assess the impacts from any lessening of competition likely to result from the 

imposition of such standards. (42 U.S.C. 6295(o)(2)(B)(i)(V) and (B)(ii)) Publication of the 

NOPR is followed by a public comment period that includes a public meeting.

2.2.3 Final Rule

After publication of any NOPR, DOE considers public comments received on the 

proposal and accompanying analyses. DOE reviews the engineering and economic impact 

analyses and any proposed standards based on these comments and considers modifications 

where necessary. DOE also considers DOJ’s comments on the NOPR relating to the impacts of 

any proposed standard levels on competition to determine whether changes to these standard 

levels are needed. DOE publishes the DOJ comments and DOE’s response as part of any final 

rule.

In the final rule, DOE sets final standard levels and the compliance date and also explains

the basis for the selection of such standard levels. The final rule is accompanied by a final TSD.

 

10 TSLs are assembled from the CSLs analyzed for the individual product classes based on a set of criteria from the 

analysis results.
12

2.2.4 Overview of Analyses for Rulemaking

The purpose of the analyses conducted in support of the standards rulemaking is to ensure 

that DOE selects energy conservation standards that achieve the maximum improvement in 

energy efficiency that is technologically feasible and economically justified, and will result in 

significant energy savings. Economic justification includes the consideration of economic 

impacts on domestic manufacturers and consumers, national benefits including environmental 

impacts, issues of consumer utility, and impacts from any lessening of competition. DOE expects 

the selection of such standards to achieve the maximum energy savings that are economically 

justified without imposing excessive financial burden on any particular party. 

Figure 2-1 summarizes the analytical components of the standards-setting process. The 

“analyses” are presented in the center column. Each analysis has a set of “key inputs,” which are 

data and information required for the analysis. “Approaches” are the methods that DOE will use 

to obtain key inputs, which may vary depending on the information in question. For example, 

some key inputs exist in public databases; DOE will collect other information from interested 

parties or experts with special knowledge, and DOE will gather other information in support of 

this rulemaking. The results of each analysis are “key outputs,” which feed directly into the 

rulemaking. Arrows indicate the flow of information between the various analyses. DOE ensures 

a consistent approach to its analyses throughout the rulemaking by considering each analysis as a 

part of the overall standards-setting framework. 
13

Figure 2-1: Flow Diagram of Analyses for a Traditional Standards Rulemaking Process
14

3. SCOPE OF COVERAGE

In the February 2014 NOPD, DOE proposed the following definition for computer 

systems:

“A consumer product whose primary function is to perform logical operations and process data, 

or equipment whose primary function is to maintain continuity of load power for such products 

in case of input power failure.” 79 FR 11346.

While this definition may be broad and include several products, DOE intends to narrow 

the scope of this rulemaking. As discussed in the February 2014 NOPD, DOE would consider 

consumer products such as computers, computer servers, and UPSs, to be within the scope of 

coverage of computer systems. 

DOE is considering including definitions for computers, computer servers, and UPSs to 

establish the scope of coverage for the computer systems test procedure and standards 

rulemakings. These are discussed in sections 3.1, 3.2, and 3.3, respectively. The proposed 

definitions for these types of consumer products will be the starting point to establish the scope 

of this rulemaking. DOE is considering additional criteria to further identify the types of 

consumer products that should be included in the scope of coverage, as discussed in section 3.4 

3.1 Definition of Computers

DOE is considering the following definition for a computer. 

“Computer means a consumer product powered by mains power with the primary function of 

performing logical operations and processing data. At a minimum, a computer is composed of 

the following:

(1) A central processing unit (CPU) to perform operations, or the ability to function as 

a client gateway to a server that acts as a computational CPU;

(2) User input devices such as a keyboard, mouse or touchpad; and

(3) An integrated display and/or the ability to support an external display screen to 

output information.

This definition excludes products that may perform similar operations but have different primary 

functions, including but not limited to: playing video games, displaying television signals, 

making phone calls, taking pictures, or outputting audio signals.”

This definition is based on the definition in ENERGY STAR Computers V. 6.0 with the 

exception that DOE’s proposed definition is simplified by excluding examples of specific 

products and features included in the ENERGY STAR Computers V. 6.0 definition. Further, 

DOE’s proposed definition specifies that products that have different primary functions are 

excluded. DOE is proposing this specificity to exclude products such as game consoles, digital 

cameras, smartphones, etc. from the computers definition.
15

Item 3-1 DOE requests comment on the definition of a computer or alternate 

approaches that should be considered. Specifically, DOE requests 

suggestions of characteristics that may be used in the definition to distinguish 

general consumer electronics from computers. 

3.2 Definition of Computer Servers

DOE is considering the following definition for computer servers.

“Computer server means a computer that provides services and manages networked resources for 

client devices (e.g., desktop computers, notebook computers, thin clients, wireless devices, 

personal digital assistants (PDAs), IP telephones, other computer servers, or other network 

devices). A computer server is primarily accessed via network connections, versus directly 

connected user input devices such as a keyboard or mouse. Additionally, a computer server must 

meet the following criteria:

(1) Provides support for error-correcting code (ECC) and/or buffered memory 

(including both buffered dual in-line memory modules (DIMMs) and buffered on 

board (BOB) configurations).

(2) Is designed such that all processors have access to shared system memory and are 

visible to a single operating system (OS) or hypervisor.”

This definition is based on the computer servers’ definition specified in ENERGY STAR 

Version 2.0, ENERGY STAR Program Requirement for Computer Servers, Rev. October 2013

(ENERGY STAR Computer Servers V. 2.0), except DOE’s proposed definition does not include 

language relating to whether a computer server is sold primarily to commercial customers 

through enterprise channels. Computer servers are not always sold through enterprise channels 

and are often sold for use in multiple environments in addition to office/corporate locations or 

data centers. Moreover, under EPCA, the fact that a computer server is sold only or primarily to 

commercial/industrial customers does not, alone, make it a commercial product.

DOE’s proposed definition also does not include the requirement from the ENERGY 

STAR Computer Servers V. 2.0 definition that a computer server “is designed for and listed as 

supporting one or more computer server OS and/or hypervisors”, because it may be difficult to 

create a quantitative distinction between a computer OS and a computer server OS. Additionally, 

DOE’s proposed definition does not include the requirement that a computer server “is packaged 

and sold with one or more AC-DC (alternate current-direct current) or DC-DC (direct currentdirect current) power supplies”, since the inclusion of a power supply does not provide a 

meaningful distinction between a computer and a computer server.

Although the currently proposed definition provides a functional foundation, it may not 

sufficiently distinguish between client computers, which are typically intended for single-user 

operation, and computer servers, which are designed to handle multiple simultaneous users and 

service requests sharing system resources. DOE intends to investigate further factors and criteria 

which could be used to clearly distinguish between computer servers and client computers. 
16

Item 3-2 DOE requests feedback and information on additional factors and 

criteria that could be used to distinguish clearly between computer servers

and client computers, other than those based on point-of-sale or end-use.

3.3 Definition of Uninterruptible Power Supplies

DOE is considering a definition for UPSs that is based on that of International 

Electrotechnical Commission (IEC) standard 62040-3 Edition 2.0, Uninterruptible power systems 

(UPS) – Method of specifying the performance and test requirements, March 2011 (IEC 62040-3, 

Ed. 2.0) and ENERGY STAR Version 1.0, ENERGY STAR Program Requirements for 

Uninterruptible Power Supplies, Rev. July 2012 (ENERGY STAR UPS V. 1.0). As such, DOE 

proposes to define a UPS as “a combination of convertors, switches and energy storage devices 

(such as batteries) constituting a power system for maintaining continuity of load power in case of 

primary input power failure.”

Supplementary external circuits and components such as isolation transformers and 

electromagnetic interference (EMI) filters may be needed depending on the topology of the UPS, 

the requirements of the load and the AC power distribution system.11 These external components 

provide additional utility and do not contribute to the power conversion efficiency of the UPS. 

DOE therefore intends to exclude such external components and its impact on overall efficiency 

from its analysis. 

3.4 Scope of Computer Systems Test Procedure and Standards Rulemakings

The proposed scope of coverage for the computers systems test procedure and standards 

rulemakings relates only to consumer products. EPCA defines “consumer product” as any article 

of a type that consumes or is designed to consume energy, and, to any significant extent, is 

distributed in commerce for personal use or consumption by individuals without regard to 

whether such article of such type is in fact distributed in commerce for personal use or 

consumption by an individual. (42 U.S.C. 6291(1)) Therefore, only those computer systems that 

are of a type which, to any significant extent, are distributed into commerce for personal use or 

consumption would be considered in the scope of this rulemaking. DOE received comments in 

response to the February 2014 NOPD regarding the distinction between consumer and 

commercial computer systems. The Telecommunications Industry Association (TIA) agreed with 

DOE’s clarification that this rulemaking should cover consumer products only, because 

regulating commercial products is contrary to EPCA and would have severe negative 

consequences. (TIA, No. 0023 at p. 6) The National Electrical Manufacturers Association 

(NEMA) requested DOE to identify better indicators of consumer versus commercial products 

since assumptions regarding covered versus non-covered products can result in millions of 

dollars wasted on redesigning non-covered equipment or result in significant fines for failing to 

 

11 IEC standard 62040-3 Edition 2.0, Uninterruptible power systems (UPS) – Method of specifying the performance 

and test requirements (IEC 62040-3, Ed. 2.0) 
17

redesign products mistakenly thought to be non-covered. (NEMA, No. 0025 at p. 6) The 

Appliance Standards Awareness Project (ASAP), Natural Resources Defense Council (NRDC), 

Alliance to Save Energy, American Council for an Energy-Efficient Economy (ACEEE), 

Northeast Energy Efficiency Partnerships (NEEP), Northwest Energy Efficiency Alliance 

(NEEA) and Northwest Power and Conservation Council (hereafter referred to as Joint 

Responders) commented that in the absence of a clear and lasting distinction, DOE must 

conclude that all computers are of the same type from a regulatory perspective, and therefore 

covered by the standards, irrespective of whether they are marketed to, and operated in, 

commercial settings. (Joint Responders, No. 0024 at p. 3) 

DOE is working to identify factors that can distinguish between consumer and 

commercial products so that only computer systems which are consumer products are included in 

scope. The Information Technology Industry Council (ITI) commented that residential products 

have electrical capacity limits and many computer servers and UPSs are not designed for 

residential AC mains. (ITI, No. 0026 at p. 5) Finally, Schneider Electric recommended DOE to 

refer to its White Paper on different AC power connectors for distinguishing consumer from 

commercial products. (Schneider Electric, No. 0019 at p. 8) DOE is considering using the 

criterion mentioned by ITI to distinguish between consumer and commercial products as 

discussed in further detail in sections 3.4.1, 3.4.2, and 3.4.3. DOE will also review Schneider 

Electric’s White Paper on AC power connectors. DOE is additionally considering whether 

specific types of computers, such as tablets, should be considered in scope as discussed in 

section 3.4.1.

3.4.1 Computers

In response to the February 2014 NOPD, ITI commented that with respect to personal 

computers, the basic design is similar to devices sold to commercial customers. (ITI, No. 0026 at 

p. 6) ITI specified that commercial products are differentiated from consumer products in one or

more of the following areas: remote management capabilities; availability and serviceability; 

expandability; and longer warranty periods. However, these differences are not clear delineators 

of the two end use markets. (ITI, No. 0026, at p. 6)

Accordingly, at this initial stage, DOE is not aware of any computers that would be 

considered commercial/industrial equipment only. 42 U.S.C. 6311(2)(A) Therefore, DOE is 

considering including all computers within scope except as discussed below.

DOE evaluated industry, regulatory, and voluntary standards for computers to determine 

their scope (discussed in section 4.1.1). The scope of these industry standards are detailed in 

Appendix A. Based on its initial review of industry and regulatory energy programs for 

computers, DOE is considering including desktop, integrated desktop, notebook, thin client, 

mobile thin client, and integrated thin client computers in the scope of this rulemaking. DOE is 

still evaluating the impact of including workstations, small-scale servers, and tablet computers in 

the scope of coverage. 

ENERGY STAR Computers V. 6.0 specifies definitions for all these product types, 

except tablets, and uses these definitions to define its scope. DOE is considering the definitions 

specified in ENERGY STAR Computers V. 6.0 to define the scope for computer product types. 
18

Further, the U.S. Environmental Protection Agency (EPA) is currently revising the ENERGY 

STAR Computers V. 6.0 specification and published the ENERGY STAR Version 6.1 Final 

Draft Computers Specification (ENERGY STAR Computers Final Draft V. 6.1) on June 23, 

2014. In this revision, EPA is updating definitions for some products, such as integrated desktop 

and DOE will consider the updated definitions, once the specification is final. While DOE may 

consider excluding some of these products from scope, clear product definitions will help avoid 

product overlap and confusion.

While a definition for tablet computers is excluded from ENERGY STAR Computers V. 

6.0, EPA recognizes the need for its definition and is considering including slates/tablets in the 

ENERGY STAR Computers Final Draft V. 6.1 revision. The draft specification proposes a 

definition for slates/tablets and revises the scope to exclude handheld computers with cellular 

voice capability.

DOE believes that a definition for tablet computers may be necessary to distinguish them 

from similar products like notebook and integrated desktop computers. These products share 

many physical similarities like integrated touch screens and main batteries, but tablet computers 

are designed for increased portability making them ideal for usage while disconnected from 

mains power. This difference in usage can impact the overall usage profile and energy 

consumption of the product, reinforcing the need to separate these products. Therefore, DOE will 

consider the definition for slates/tablets that is included in the ENERGY STAR Computers Final 

Draft V. 6.1 once the specification is final.

Item 3-3 DOE requests comment on using ENERGY STAR Computers V. 6.0 and 

ENERGY STAR Computers Final Draft V. 6.1 as the basis for computer 

product definitions. DOE also requests comment on any additional computer 

product definitions that should be included.

Item 3-4 DOE requests comment on the need for a tablet computer definition. 

DOE also requests comment on the criteria used to distinguish tablet 

computers from other computers as well as any suggestions for the definition. 

While DOE is considering using the definitions of desktops, notebooks, and other 

products to establish the scope of included computer product types, it is also considering 

defining the scope without using these product definitions. In the latter scenario, DOE would 

establish bounds in scope through product features and technical specifications. With the rapidly 

changing form factor of computers, this may be a more accurate method to ensure that only the 

intended product characteristics are included in the scope. 

Specifically, DOE is considering certain product characteristics for scope criteria such as 

product weight, screen size, integrated mechanical keyboards, touch screen sensitivity, main 

batteries, battery capacity, power supply size, and internal storage. For example, DOE may 

decide that notebooks under a certain screen size do not need to be included in the scope or 

tablets with screens greater than a certain size should be included. Or DOE may decide to 
19

exclude smaller products that are already energy efficient and face design constraints due to their 

size. 

Item 3-5 DOE requests comment on the types of computers that should be 

excluded from the scope. 

Item 3-6 DOE requests comment on using computer product characteristics to 

narrow the scope of coverage or more accurately define products. In 

particular, what design characteristics would best be used to separate out 

tablets? 

3.4.2 Computer Servers

DOE evaluated regulatory and voluntary standards for computer servers to determine the

types of servers that should be included in scope (discussed in section 4.2.1). The scope of these 

industry standards are detailed in Appendix A. Of these standards, DOE primarily reviewed the 

scope requirements in ENERGY STAR Computer Servers V. 2.0. The scope of this program 

includes blade, multi-node, rack-mounted, and pedestal form factor computer servers with no 

more than four processor sockets in the computer server (or per blade or node in the case of 

blade or multi-node servers).

As discussed previously, DOE is considering only computer servers that are consumer

products for the scope of this rulemaking. Although the scope of ENERGY STAR Computer 

Servers V. 2.0 targets products that are “sold through enterprise channels for use in data centers 

and office/corporate environments”, DOE believes that many of the products within the 

ENERGY STAR scope are also purchased and used by consumers. Computer servers that are 

used for these household purposes are available to consumers through retail outlets12, 13, 14 and 

are typically sold alongside computer servers that are targeted more towards home office and 

small business applications. 

However, since certain products that are included in the scope of ENERGY STAR 

Computer Servers V. 2.0, such as blade systems or resilient servers, might not be considered 

consumer-type products, DOE is considering excluding such items from the scope. 

In response to the February 2014 NOPD, DOE received several comments regarding the 

distinction between consumer and commercial servers. International Business Machines 

Corporation (IBM) commented that computer servers are wholly unlike personal computing 

equipment and they are not used in a residential environment; therefore, they should be excluded 

 

12 http://www.amazon.com/

13 http://www.tigerdirect.com/

14 http://www.newegg.com/
20

from the regulation. (IBM, No. 0021 at p. 2) ITI commented that the subset of computer servers 

that may be used in both a home and commercial environment are limited and can be defined 

based on sales, ability to be powered by residential circuits, and by the fact that they are 

configured to be installed and used in a residential setting. (ITI, No. 0026 at p. 5) ITI also 

included an Appendix that contained comments from Cisco. The comments described 

distinguishing features and characteristics of commercial servers compared to servers sold for 

personal use or consumption. Cisco commented that servers used in data centers have 

enormously large memory stores, are maintained by advanced cooling systems, are connected to

very powerful processors, and are powered by energy supplies that are meant to stay on for years 

at a time. Whereas, home servers are used to manage and stream video and music content, share 

photos, store emails and backup copies of files, remotely control computers and local area 

network applications, automate home functions, and potentially host small business websites. 

That is, the extent to which a data center server or a large enterprise server can be used in a 

residential application is near zero. (ITI Appendix 3, No. 0023 at p. 8-10, 14) Cisco further 

commented that data center and network servers operate in an entirely different manner to home 

servers. Further, while some components are similar, the processes for storing and moving data 

are different, as is the typical usage actively needed to generate data, where they are placed, what 

they connect to, and the amount of energy they consume. (ITI Appendix 3, No. 0023 at p. 12) 

Finally, Cisco commented that while a home server can operate on any flat surface in a house in 

any climate, commercial-grade servers typically require a temperature between 65 – 75 degrees 

Fahrenheit and a monitoring system with temperature sensors and responsive cooling systems. 

(ITI Appendix 3, No. 0023 at p. 13-14)

While DOE is not considering using point of sale or configurability as a method to 

distinguish between commercial and consumer computer servers, it may consider ITI’s 

recommendation of qualifying computer servers based on ability to be powered by residential 

circuits. Accordingly, DOE will consider limiting the scope to computer servers that can be 

powered using 120 Volts (V) input or a standard wall plug receptacle. Further, while DOE is 

considering physical design and hardware features as a basis for distinguishing between 

commercial and consumer computer servers, certain other features are not being considered. For 

example, although computer servers designed for a commercial deployment may be capable of 

providing longer periods of reliable and uninterrupted service than those designed for consumer 

use, such a characteristic may be difficult to quantify and verify. Additionally, there is often 

overlap between the applications performed by commercial and consumer computer servers (e.g., 

serving multimedia, storing files, hosting websites), with the difference between the two types 

being performance requirements and scale of operation. DOE believes that it may be challenging 

to distinguish between commercial and consumer products based on such nuances, whereas the 

scale and performance capability of a computer server might be strongly correlated with its 

hardware and physical design characteristics. Finally, if certain commercial computer servers 

require external hardware or system infrastructure to function properly, such criteria may be 

considered as a method to distinguish from consumer computer servers. 

Currently, DOE believes that of the three market segments of computer servers shown in 

Table 1-1 (volume, mid-range, and high-end), the volume computer servers category would 

primarily be considered a consumer product. However, this market segmentation of computer 

servers is based on cost, which DOE will likely not use to determine the scope, as that may 

change over time. Therefore, DOE is investigating other methods by which to define the scope to 
21

include only computer servers that are consumer products. An option that DOE is considering is 

based on the distinction used in ENERGY STAR Computer Servers V. 2.0, which includes a 

computer server’s form-factor as a basis for determining whether it is included within the scope 

of coverage. DOE is also investigating alternative strategies that focus on a computer server’s 

quantifiable characteristics (e.g., number of processor sockets, memory capacity, maximum 

theoretical performance, etc.).

Item 3-7 Based on DOE’s definition of a consumer product, DOE requests 

comment on additional methods (besides ability to operate on a residential 

circuit) to identify computer servers that are consumer products. Are there 

alternative strategies that can be used to create a scope of coverage which 

distinguishes consumer computer servers from those that are exclusively used 

in commercial/data-center environments?

3.4.3 Uninterruptible Power Supplies

A UPS has two primary functions. The first is to provide an instantaneous and 

uninterrupted source of emergency power in the event of a mains power failure. The second is to 

monitor and condition the mains power to protect sensitive electronic equipment against voltage 

surges, sags, switching transients, line noise and harmonic distortion. UPS applications can 

therefore extend from typical consumer use among households where there is a need to protect 

vulnerable loads such as personal computers and home entertainment systems to commercial 

applications such as at datacenters, public utilities, telecommunications, medical institutions and 

manufacturing environments. 

As mentioned previously, DOE’s intention is to only develop standards and test 

procedures for consumer products. Thus, the scope of this rulemaking will be limited to UPSs 

that fall within EPCA’s definition of a consumer product. DOE reviewed the scope of the 

ENERGY STAR UPS V. 1.0 specification in consideration for the scope of this rulemaking. Of 

the products that are in scope for ENERGY STAR UPS V. 1.0, DOE is considering including 

consumer UPSs that are intended to protect desktop computers and related peripherals, and/or 

home entertainment devices such as TVs, set top boxes, digital video recorders (DVRs), Blu-ray 

and digital video disc (DVD) players.

ENERGY STAR UPS V. 1.0 also includes several commercial UPSs in scope, that DOE 

is considering excluding. Further, DOE is considering excluding the following products from the 

scope of this rulemaking, despite meeting the definition of a UPS:

(1) UPSs designed to comply with specific UL safety standards for safety-related 

applications, such as emergency lighting, operations or egress, or medical 

diagnostic equipment.

(2) UPSs designed for mobile, ship board, marine or airborne applications. 

DOE received input from stakeholders to identify consumer UPSs from commercial 

UPSs in response to the February 2014 NOPD. IBM commented that DOE should remove 
22

battery backup systems from the proposed determination because they do not meet the EPCA 

definition of a consumer product nor are they a product “of a type” under DOE’s FAQ “several 

factors” test.

15 (IBM, No. 0021 at p. 2) NEMA commented that if there is a need to regulate UPS 

products under EPCA, the definition should include mention of standard two and three prong 

power cords and that these systems should not draw more than 7 amps of power. (NEMA, No. 

0025 at p. 5) Further, all rack mounted or rack mountable devices and equipment requiring 

multiphase power or other than 120 V AC should be clearly excluded from scope since these 

items would not be consumer devices. (NEMA, No. 0025 at p. 5) NEMA also commented that to 

avoid regulatory ambiguity, DOE should avoid definitions that capture a much broader range of 

products during certification and enforcement unless additional qualifications are set to clarify 

the determination of consumer products. (NEMA, No. 0025 at p. 5) Schneider Electric 

commented that consumer UPSs are defined as voltage and frequency dependent (VFD), which 

have a different architecture compared to business class UPSs that are defined by IEC 62040, Ed. 

2.0 as voltage and frequency independent (VFI) and voltage independent (VI). (Schneider 

Electric, No. 0019 at p. 3) Schneider Electric further commented that, for the purposes of UPSs 

supporting consumer products, the voltage is 120 V AC exclusively, connected to a 15 amp multi 

outlet residential branch circuit. Schneider Electric utilizes several technical characteristics for 

defining their consumer marketplace and recommended the following: pluggable Type A 

equipment (as defined by IEC 60950-1); products marked as compliant with class B emissions 

limits (47 CFR 15, or EN 55022); and VFD type UPSs. (Schneider Electric, No. 0019 at p. 6 – 7) 

Further, commercial and industrial UPSs can be identified using the following characteristics: 

Products marked as compliant with class A emissions limits (47 CFR 15 or EN 55022); 

equipment requiring multiphase power input or power input other than 120 V AC; computers and 

UPSs with greater than 12 amps power draw, at 120 V; computers and UPSs with voltage input 

other than 120 V AC; and, any rack mounted system – the 19 inch rack mount systems are 

indicative of commercial applications. (Schneider Electric, No. 0019 at p. 7)

DOE is considering identifying consumer type UPSs as those operated at 120 V AC on a 

standard wall plug receptacle as commented by NEMA and Schneider Electric. In order to give 

manufacturers freedom to deploy any technology necessary when meeting standards, DOE will 

not use product architecture to distinguish between consumer and commercial UPSs unless 

certain architectures are associated with customer utility that are not offered otherwise. DOE is 

investigating alternative methods and will attempt to harmonize with current definitions for 

consumer UPSs as defined in IEC 62040, Ed. 2.0. 

Item 3-8 DOE requests feedback on the proposed scope for UPSs. In particular, 

whether or not industry believes a particular UPS type should be included 

within the scope.

 

15 http://www1.eere.energy.gov/buildings/appliance_standards/pdfs/cce_faq.pdf
23

DOE is also considering the use of product characteristics such as overall capacity (in 

VA) to limit the scope of coverage. DOE believes a cut-off capacity will allow consumer UPSs 

to be regulated without impacting those used in an industrial or commercial setting. 

Item 3-9 DOE requests feedback on using UPS product characteristics to 

narrow the scope of coverage. DOE further requests feedback on whether 

capacity is a proper differentiator between consumer and commercial UPSs 

and what constitutes a proper cut-off capacity.

4. TEST PROCEDURES

DOE is considering a test procedure rulemaking for computer systems. In prescribing 

new test procedures, DOE will take into account relevant information including technological 

developments relating to energy use of computer systems. DOE plans to include the required 

definitions, test conditions, and setup requirements for computer systems in the test procedure. 

Because of the complexity of the computer systems products, the test procedure text may be split 

into different sections to account for different product classes (e.g. notebooks vs rack-servers) 

and the modal energy consumption or efficiency values will be combined in a single metric for 

the purposes of determining compliance with energy conservation standards. Additionally, due to 

the varied interests of stakeholders, DOE will consider scheduling separate public meetings to 

discuss the different sections of the test method. The following sections discuss the methods of 

energy consumption measurement for computer systems in further detail.

4.1 Methods of Measurement for Computers

4.1.1 Existing Industry and Regulatory Test Procedures

As an initial step to develop a test method for computers, DOE evaluated the following 

existing industry and regulatory programs:

(1) Australian/New Zealand Standard (AS/NZS):2012, Information Technology 

Equipment-Energy Performance of Computers, July 2012 (AS/NZS 5813:2012);

(2) European Union (EU) No. 617/2013, Implementing Directive 2009/125/EC of the 

European Parliament and the Council with regard to Ecodesign requirements for 

computers and computer servers, June 2013 (EU No. 617/2013);

(3) IEC 62623 Ed. 1.0, Desktop and Notebook Computers – Measurement of Energy 

Consumption, October 2012 (IEC 62623 Ed. 1.0);

(4) Ecma International ECMA-383 Ed. 3: 2010-12, Measuring the Energy 

Consumption of Personal Computing Products, December 2010 (ECMA-383 Ed. 

3.0);

(5) ENERGY STAR Computers V. 5.2; 

(6) ENERGY STAR Computers V. 6.0; and
24

(7) Japan’s Computer and Hard Disk Drive Judging Standards Subcommittee Final 

Report, General Resources Energy Investigation Committee, Energy Savings 

Standards Section, Rev. December 2009 (Japanese Top Runner Program).

While ENERGY STAR Computers V. 5.2 was effective until June 1, 2014, EPA released 

ENERGY STAR Computers V. 6.0 as an updated version that went into effect on June 2, 2014. 

Further, the Final Draft version of ENERGY STAR Computers V. 6.1 was published recently 

and will supersede ENERGY STAR Computers V. 6.0 once it goes into effect. DOE has 

primarily evaluated ENERGY STAR Computers V. 6.0 for the computers test method in 

advance of the publication of this framework document, but will consider any additional 

requirements specified in ENERGY STAR Computers V. 6.1 once the final version is published.

4.1.2 Proposed DOE Test Method for Computers

Of the computer standards DOE evaluated, the Japanese Top Runner Program has the 

most notable differences compared to the other standards. While the other procedures closely 

align with the measurement practices of IEC 62623 Ed. 1.0, the Japanese Top Runner Program 

uses a unique procedure to determine an efficiency level for computers. Additionally, its power 

measurements are vague in comparison to the other industry procedures. Therefore, DOE did not 

consider the Japanese Top Runner Program to propose a test method for measuring computer 

energy consumption.

Of the other standards evaluated, although ENERGY STAR Computers V. 5.2 and EU 

No. 617/2013 follow the same procedural style of IEC 62623 Ed. 1.0, they only measure one idle 

mode of operation. Whereas, ENERGY STAR Computers V. 6.0, ECMA-383 Ed. 3.0, AS/NZS 

5813:2012, and IEC 62623 Ed. 1.0, measure idle mode in two parts, short and long idle, because 

it’s believed to be a more typical representation of the computer’s idle mode power consumption. 

DOE agrees with this approach and is considering a short and long idle mode power 

measurement. DOE is therefore considering IEC 62623 Ed. 1.0 as the basis for its computers test 

procedure. 

The IEC 62623 Ed. 1.0 test procedure defines methods for determining the power 

consumption of computers in the off, sleep, long idle, and short idle modes. The test procedure 

includes definitions for different modes of operation and test setup instructions in addition to the 

power consumption test methods. DOE supports these procedural methods and may consider the 

IEC 62623 Ed. 1.0 test procedure as a basis for the computers test method. Additionally, DOE 

observes that ENERGY STAR Computers V. 6.0 provides additional guidance for the power 

measurements and for setting the luminance of integrated displays to a predetermined value. 

DOE will consider this guidance while developing the computer test method as well.

Item 4-1 DOE requests comment on the use of IEC 62623 Ed. 1.0 as the basis

for the development of the computers test method.
25

Item 4-2 DOE requests comment on providing additional guidance as provided 

in ENERGY STAR Computers V. 6.0. Specifically, DOE requests comment on 

the luminance values specified in ENERGY STAR Computers V. 6.0 for 

integrated desktops and notebooks. Are these values sufficient or does the 

luminance need to be higher for integrated displays?

4.1.3 Annual Energy Consumption Metric

Test procedure output metrics are used in the energy conservation standard to determine

if the product meets the standard level. When considering this metric, DOE reviewed output 

metrics and implementation methods from regulatory and voluntary programs. Most standards 

that measure the energy use of computers use a weighted average of modal power consumption 

values to determine an AEC value, in kWh per year. ENERGY STAR, AS/NZS, and EU all use 

this method, while the Japanese Top Runner Program uses a watts-per-operation metric. Due to 

the substantial difference between the watts-per-operation metric used by Japan and an AEC 

metric, DOE is considering an AEC metric which harmonizes with ENERGY STAR.

The weighting values associated with each measured mode of operation are necessary to 

create a representative AEC value. AS/NZS 5813:2012 and EU No. 617/2013 use the weightings 

specified by ENERGY STAR Computers V. 5.2, which are based upon a 2008 study by 

Microsoft16 and do not distinguish between the short idle and long idle modes. ENERGY STAR 

Computers V. 6.0 uses weightings based upon a 2010 study that was released along with 

ECMA-383 Ed. 3. This study measures usage in both the short idle and long idle modes, though 

it does not differ greatly from the Microsoft study in its weighting scheme. Table 4-1 lists the 

mode weightings found in ENERGY STAR Computers V. 6.0 for computers without any 

network proxy functionality.

Table 4-1: ENERGY STAR Computers V. 6.0 Modal Weightings, based on ECMA-383

Ed. 3

Mode Desktops*

%

Laptops

%

Off 45 25

Sleep 5 35

Long Idle 15 10

Short Idle 35 30

Active 0 0

*Weightings for desktops also apply to integrated desktops and thin clients

The active mode of operation was assigned a 0% weighting because computers spend 

relatively little time with significant CPU usage, and the ECMA-383 Ed. 3 study found that 

approximating active mode under short idle mode yielded accurate results for energy use.

 

16 Microsoft Power Transition Report, 2008; 

<www.energystar.gov/ia/partners/prod_development/revisions/downloads/computer/Microsoft_PowerTransitionRep

ort.pdf?%%20f0fe-40d2>
26

Based on these reports, DOE is considering including the AEC mode weightings and 

definitions based on ENERGY STAR Computers V. 6.0 for evaluating the energy consumption 

of computers.

Item 4-3 DOE requests comment on the inclusion of ENERGY STAR Computers 

V. 6.0 mode weightings.

4.1.4 Annual Energy Consumption Metric for Computers with a Network Proxy

Network proxying is a function that allows the computer to remain connected to a 

network through an intermediary while the computer is in a low power state such as sleep mode. 

By giving the computer greater functionality in sleep mode, the network proxy may shift the 

amount of time spent in more energy consumptive operational modes, such as long and short 

idle, to sleep mode. However, network proxying may also decrease the amount of time spent in 

off mode in exchange for time spent in sleep mode because of this additional functionality. 

The result of spending more time in sleep mode is that the computer may ultimately 

consume less energy. ENERGY STAR Computers V. 5.2 and V. 6.0 recognize the potential shift 

in modal usage due to network proxying and offer different modal weightings based on the 

proxy’s functionality. The ENERGY STAR Computers V. 6.0 weightings are shown in Table 

4-2 and Table 4-3.

Table 4-2: ENERGY STAR Computers V. 6.0 Modal Weightings with Proxy for Desktop, 

Integrated Desktop and Thin Client Computers

Mode Conventional 

%

Base 

Capability %

Remote Wake 

%

Service/Name 

Discovery %

Full 

Capability %

Off 45 40 30 25 20

Sleep 5 15 28 36 45

Long Idle 15 12 10 8 5

Short Idle 35 33 32 31 30

Table 4-3: ENERGY STAR Computers V. 6.0 Modal Weightings with Proxy for Notebook 

Computers

Mode Conventional 

%

Base 

Capability %

Remote Wake 

%

Service/Name 

Discovery %

Full 

Capability %

Off 25 25 25 25 25

Sleep 35 39 41 43 45

Long Idle 10 8 7 6 5

Short Idle 30 28 27 26 25

ENERGY STAR Computers V. 6.0 sets weightings based on four levels of proxy 

functionality – base capability, remote wake, service/name discovery, and full capability. For 

each successive level it increases the weighting allocated to sleep mode and decreases the 

weighting allocated to other modes to compensate. The conventional weighting in ENERGY 

STAR Computers V. 6.0 is based on a robust study that was released along with ECMA-383 Ed. 

3 in 2010.
27

Item 4-4 DOE requests comment on adopting the ENERGY STAR Computers V. 

6.0 weightings for AEC based on network proxy functionality. Specifically, 

DOE requests comment on the weighting values assigned to each proxy level.

While DOE is considering these network proxy modes for the DOE test procedure, it is 

concerned that the difference in functionality may be difficult to discern. DOE requests comment 

on appropriate methods to identify a computer’s network proxy functionality that is not tied to 

the use of a specific software version.

Item 4-5 DOE requests comment on a standardized and objective method to 

identify the level of proxy functionality on computers. Specifically, DOE 

welcomes information on steps that can objectively determine the proxy level 

on different OSs.

DOE is considering an alternate solution for network proxy functionality; a simplistic 

approach that only uses two network proxy modes, a conventional weighting for computers 

without any network proxy functionality, and a weighting for computers with full network proxy 

functionality. DOE recognizes that this approach may not allow the computer’s network proxy 

functionality to be easily identified. Therefore, it is considering a weighting system without any 

network proxying, using only the conventional weightings specified in ENERGY STAR 

Computers V. 6.0. DOE requests stakeholder feedback on an appropriate approach to address 

network proxying. DOE’s goal is to propose an approach that is representative of the computer’s 

AEC, yet simplistic enough so that network proxying can be easily identified.

Item 4-6 DOE requests comment on the best approach to address network 

proxying: (a) using four levels of weightings for proxy functionality as 

specified in ENERGY STAR Computers V. 6.0 in addition to the conventional 

weightings; (b) using two levels of weightings, one for no network proxy 

functionality and the other for network proxy functionality; and, (c) using a 

single weighting for all computers.

Item 4-7 For each of the approaches, DOE requests comment on the network 

proxy weighting that is representative of the computer’s AEC and is 

identifiable on all OSs.

4.2 Methods of Measurement for Computer Servers

4.2.1 Existing Regulatory and Voluntary Test Procedures

As an initial step to develop a test method for computer servers, DOE evaluated the 

following existing programs:

(1) EU No. 617/2013; 
28

(2) Japanese Top Runner Program; 

(3) South Korea Ministry of Knowledge Economy (MKE) Notification No. 2011-23, 

Regulation on Standby Power Reduction Program, e-Standby program, February 

2011 (Korea MKE No. 2011-23); and

(4) ENERGY STAR Computer Servers V. 2.0.

EPA collaborated with DOE to establish ENERGY STAR Computer Servers V. 2.0. This 

voluntary program targets blade, multi-node, rack mounted, and pedestal servers with four or 

fewer physical CPUs. It focuses on testing of idle and active states, but only sets levels for idle 

state power measurements for qualification. 

Of the other regulatory standards that DOE evaluated, EU No. 617/2013 does not include 

a test procedure, and Korea MKE No. 2011-23 measures standby power of the products covered. 

The most directly applicable standard for computer servers is ENERGY STAR Computer 

Servers V. 2.0 and the Japanese Top Runner Program.

The Japanese Top Runner Program measures the energy consumption of the low power 

state and idle mode, but only provides general set-up requirements like ambient temperature and 

supply voltage rather than specific measurement criteria. DOE is still considering these modes of 

operation for computer servers. However, due to the lack of detail in this procedure, DOE is not 

considering the Japanese Top Runner Program for the basis of its test procedure.

The ENERGY STAR Computer Servers V. 2.0 test procedure includes two distinct 

testing paradigms: idle state and active state. The idle state test describes a methodology to 

determine a computer server’s power consumption while operating in an inactive state. The 

active state testing measures a computer server’s power consumption while it performs a variety 

of tasks that are representative of typical computer server applications. In the ENERGY STAR 

Computer Servers V. 2.0 test procedure, the active state test is performed using benchmarking 

software called Server Efficiency Rating Tool (SERT), which is developed by Standard 

Performance Evaluation Corporation (SPEC). The ENERGY STAR test method also provides 

comprehensive guidance for testing modern form-factors such as blade and multi-node computer 

servers. Because it is applicable to a wide cross section of modern computer servers, and 

includes testing requirements for idle and active state power measurements, DOE is considering 

ENERGY STAR Computer Servers V. 2.0 as the basis for the computer servers test method. 

Additionally, this program has recently finished its second major version, which included 

a substantial level of stakeholder involvement during its development. 

4.2.2 Proposed DOE Test Method for Computer Servers

To measure the energy consumption of computer servers, DOE is considering measuring 

the power consumption only in active mode, which is defined in EPCA, as amended, as a 

condition in which an energy-using product is connected to a mains power source, has been 

activated, and provides one or more main functions. (42 U.S.C. 6295(gg)(1)(A)(i) 
29

A computer server would be considered to be in active mode when it is either in idle state 

or active state as defined in ENERGY STAR Computer Servers V. 2.0. While ENERGY STAR 

Computer Servers V. 2.0 includes tests for both active and idle states, DOE is considering only 

the idle state energy consumption for the purposes of this rulemaking as discussed below. 

DOE and EPA have worked closely with SPEC to aid in their development of an active 

state test, SERT, but because it is still in the early stages of development, it may not be 

appropriate for DOE to incorporate this into a test procedure. The main disadvantage to the 

SERT workload is that it is currently not compatible with all computer servers. Additionally, it is 

unclear how an active state energy consumption value would be derived from the multiple output 

values of SERT. Further, DOE is not aware of any other active state test that can be performed 

on all computer servers that accounts for variation in product functionality. 

Further, computer servers spend a considerable amount of time in idle state17 and a study 

by Meisner, et al.18 shows that deployed computer servers typically process workloads in bursts –

a brief period (few hundred milliseconds) of system activity – which is followed by a 

comparably long period of inactivity. Based on DOE’s evaluation of the ENERGY STAR list of 

qualified products, Koomey’s analysis of product types19, and DOE’s assumptions on the 

utilization of consumer computer servers, DOE believes that the amount of energy observed by 

an idle state test represents a large portion of the total energy consumption of a computer server. 

Therefore, DOE is considering adopting the idle state test method specified in ENERGY STAR 

Computer Servers V. 2.0 to determine the active mode energy consumption of computer servers. 

The ENERGY STAR test method includes procedural and configuration requirements for 

determining the power consumption of computer servers while operating in idle state, which 

DOE is considering for this rulemaking.

DOE is not considering energy consumption measurements in any other modes of 

operation for computer servers, including standby and off modes. EPCA, as amended, defines 

standby mode as the condition in which an energy-using product is connected to the mains power 

source and offers one or more of the following functions: (a) to facilitate the activation or 

deactivation of other functions by remote switch, internal sensor, or timer; and (b) continuous 

functions, including information or status displays or sensor based functions. (42 U.S.C. 

6295(gg)(1)(A)(iii) With respect to computer servers, DOE believes that it would rarely be in 

standby mode. A computer server would be in standby mode after it is powered off and is 

capable of being powered on via a network command using wake-on-LAN (WOL). However, a 

computer server in such a state would be incapable of responding immediately to service 

requests or complete workload transactions. Being able to respond rapidly and reliably to 

requests at any time is one of the computer server’s primary functions; it is designed to be on all 

 

17 X. Fan, W.-D. Weber, and L.A. Barroso, “Power Provisioning for a warehouse-sized computer,” in Proc. of the 

34th Annual International Symposium on Computer Architecture, 2007.

18 Meisner, D., Gold, B., Wenisch, T., PowerNap: Eliminating Server Idle Power. 2009. University of Michigan” 

Ann Arbor, MI.

19 Koomey, Jonathan. Growth in Data Center Electricity Use 2005-2010. Analytics Press. 2011.
30

the time. Therefore, DOE expects that most computer servers rarely operate a standby mode, 

since it would take too long to respond to service requests. 

A computer server would be considered in off mode if it has been powered off and can be 

powered on again only via a tactile switch or button on the computer server case. Many 

computer servers do not have such a switch to power off the computer server, therefore, DOE 

does not expect computer servers to have an off mode.

Item 4-8 DOE requests comment on the use of the idle state test from the 

ENERGY STAR Computer Servers V. 2.0 Test Method for computer servers as 

a base for the development of the computer servers test method.

4.3 Methods of Measurement for Uninterruptible Power Supplies

4.3.1 Existing Industry Test Procedures

As an initial step to developing a test method for UPSs, DOE evaluated the following 

existing programs:

(1) IEC 62040-3 Ed. 2.0; and

(2) ENERGY STAR UPS V. 1.0.

Of these standards, the ENERGY STAR UPS V. 1.0 test method builds heavily on the 

IEC 62040-3 Ed. 2.0 standard, which has significant consensus among manufacturers in the 

industry. However, the ENERGY STAR test method offers additional guidance to implement 

IEC 62040-3 Ed. 2.0. 

Both IEC 62040-3 Ed. 2.0 and ENERGY STAR UPS V. 1.0 require the unit under test to 

achieve steady state before test measurements are made. ENERGY STAR UPS V. 1.0 further 

describes how to determine if steady state has been reached. IEC 62040-3 Ed. 2.0 does not 

explicitly provide any such instructions. 

Further, ENERGY STAR UPS V. 1.0 requires input and output energies (in Wh) to be 

measured for a given interval. This measurement is then time averaged to obtain input and output 

power specification. The approach in IEC 62040-3 Ed. 2.0 is different and requires instantaneous 

and direct measurement of power using appropriate test equipment. The fundamental unit of 

measurement is therefore different. 

Finally, IEC 62040-3 Ed. 2.0 provides efficiency allowances for external components 

such as isolation transformers and input filters and provides detailed instructions on how to 

incorporate them into the test process. ENERGY STAR UPS V. 1.0 does not consider such 

external components as part of the system and therefore does not provide a lowered efficiency 

requirement to accommodate them.
31

4.3.2 Proposed DOE Test Method for Uninterruptible Power Supplies

Of the standards DOE evaluated, the ENERGY STAR UPS V. 1.0 test method builds on 

that of IEC 62040-3 Ed. 2.0, but simplifies the qualification requirements using efficiency 

equations that extrapolate to UPSs of all power ranges. ENERGY STAR UPS V. 1.0 further 

simplifies the requirements by being voltage-independent. DOE is considering referring to the 

IEC 62040-3 Ed. 2.0 test procedure for the purposes of the UPS test method, with the inclusion 

of additional guidance outlined in ENERGY STAR V. 1.0 test method. 

To analyze the energy efficiency of a UPS, both IEC 62040-3 Ed. 2.0 and ENERGY 

STAR UPS V. 1.0 require that power consumption be measured with a reference test load that is 

25%, 50%, 75% and 100% of the unit’s rated power. Each of these individual efficiency data 

points is then weighted by a coefficient appropriate for that type of UPS and combined to 

determine the overall average efficiency of the unit. DOE will consider using a similar approach 

in its own test procedure rulemaking.

Item 4-9 DOE requests feedback on its adoption of the IEC 62040-3 Ed.2.0 

standard as a basis for the development of the UPS test method, while 

considering additional guidance provided in ENERGY STAR UPS V. 1.0. 

5. PRODUCT CLASSES

For the energy conservation standards rulemaking, DOE will consider efficiency 

standards for products that are within the scope of the test procedure rulemaking. However, DOE 

may or may not establish standards for all products that are in the test procedure scope.

As part of the analysis for developing an energy conservation standard, DOE is required 

by EPCA to achieve maximum energy efficiency improvements that are economically and 

technologically feasible. As part of this process, when necessary, DOE establishes product 

classes that group products with similar characteristics together for the purpose of establishing 

appropriate standard levels for each product class. DOE divides covered products into classes by: 

(a) the type of energy used; (b) the capacity of the product; or (c) any other performance-related 

feature that justifies different standard levels, such as features affecting consumer utility. (42 

U.S.C. 6295(q)) 

For the computer systems energy conservation standards rulemaking, DOE proposes that

product classes be determined on the basis of form factor and functionality delivered to the 

consumer. Product classes are particularly effective for establishing energy conservation 

standards when the power consumption varies between different product types. For instance, 

there is considerable variation in the power consumption between desktop computers, notebook 

computers, rack servers, and blade servers, which requires different standard levels. The 

following sections discuss some of the options for product classes for computers, computer 

servers, and UPSs.
32

Item 5-1 DOE requests comment on the proposed approach for determining 

computer systems product classes. DOE welcomes comments on any design 

characteristics that should be considered when establishing product classes.

5.1 Computer Product Classes

5.1.1 Existing Voluntary and Regulatory Standards

As part of the rulemaking process, DOE is evaluating product class structures in existing 

industry and regulatory programs. AS/NZS 5813:2012 and EU No. 617/2013 utilize a 

categorization for desktop, integrated desktop, and notebook computers that is based on 

ENERGY STAR Computers V. 5.2. However, these international standards also use the graphics 

AEC allowance structure from ENERGY STAR Computers V. 6.0. This specification mirrors 

ECMA-383 Ed. 3 and offers seven different energy allowance levels based on graphics 

performance. All of these standards provide additional AEC allowances for other performance 

features. Although there are some subtle differences between the classification systems in these 

standards, all use the same fundamental principles of establishing a base category, and further 

separating products based on performance and capabilities. 

DOE also evaluated the Japanese Top Runner Program, which uses a unique method of 

categorizing computer product classes. Japanese product classes for desktop and notebook 

computers are based on memory channels, memory capacity, graphics cards, and screen size. 

The program regulates these classes based on a maximum watts-per-operation metric, compared

to the minimum AEC allowance used by other standards. Because this structure is so different 

from other existing standards, considering this methodology may confuse and hinder efforts to 

develop a US Federal standard. Therefore, DOE is considering a product class structure which 

builds upon ENERGY STAR Computers V. 5.2 and V. 6.0, due to their influence on multiple 

industry and regulatory programs. While DOE is considering this structure, it will perform its 

own analyses to determine the minimum efficiency standards and will not directly use the 

standard specified in ENERGY STAR or other programs.

5.1.2 ENERGY STAR Computers V. 5.2 Product Overview

ENERGY STAR Computers V. 5.2 separates desktop, integrated desktop, and notebook 

computers into several categories based upon CPU performance, graphics processing unit (GPU) type, 

discrete graphics bandwidth, and system memory. Table 5-1 shows these categories. Each category is 

associated with a base requirement value, which is then subject to additional energy allowances for 

memory, graphics, and storage. Table 5-2 shows these allowance classifications for each category.
33

Table 5-1: ENERGY STAR Computers V. 5.2 Categories for Desktop, Integrated Desktop, 

and Notebook Computers

Category Description

Desktops 

and 

Integrated

Desktops

A Does not meet category B, C, or D

B CPU = 2 Physical Cores, and

Memory ≥ 2 gigabytes (GB)

C CPU > 2 Physical Cores, and

(Memory ≥ 2 GB) or (Discrete GPU)

D

CPU ≥ 4 Physical Cores, and

(Memory ≥ 2 GB) or

(GPU bandwidth (BW) > 128 bits)

Notebooks

A Does not meet category B or C

B Discrete GPU

C

CPU ≥ 2 Physical Cores,

Memory ≥ 2 GB, and

GPU BW > 128 bits
34

Table 5-2: ENERGY STAR Computers V. 5.2 Allowance Classification

Category

Memory Allowance Graphics Allowance Storage Allowance

Description

Allowance 

kWh Description Allowance kWh Description Allowance kWh

Desktops 

and 

Integrated 

Desktops

A

Memory ≤

2 GB 0

GPU BW ≤

128 bits 35 Hard drive ≤ 1

0

Memory >

2 GB 1.0*(Mem – 2) GPU BW >128 bits 50 Hard drive > 1

25

B

Memory ≤

2 GB 0

GPU BW ≤

128 bits 35 Hard drive ≤ 1

0

Memory >

2 GB 1.0*(Mem – 2) GPU BW >128 bits 50 Hard drive > 1

25

C

Memory ≤

2 GB 0

GPU BW ≤

128 bits 0

Hard drive ≤ 

1

0

Memory >

2 GB 1.0*(Mem – 2) GPU BW >128 bits 50 Hard drive > 1

25

D

Memory ≤

4 GB 0

GPU BW ≤

128 bits 0

Hard drive ≤ 

1

0

Memory >

4 GB 1.0*(Mem – 4) GPU BW >128 bits 50 Hard drive > 1

25

Notebooks

A

Memory ≤

4 GB 0

Hard drive ≤ 

1

0

Memory >

4 GB 0.4*(Mem – 4) Hard drive > 1

3

B

Memory ≤

4 GB 0

GPU BW ≤

64 bits 0

Hard drive ≤ 

1

0

Memory >

4 GB 0.4*(Mem – 4) GPU BW >64 bits 3

Hard drive > 

1

3

C

Memory ≤

4 GB 0

Hard drive ≤ 

1

0

Memory >

4 GB 0.4*(Mem – 4) Hard drive > 1

3

DOE is evaluating the potential impact of ENERGY STAR Computers V. 5.2’s 

categorization structure. Category A is treated as a catch-all for products that do not meet the

criteria for other categories, and can include great variation among products. Although DOE is 

considering this classification system, DOE may need to add specificity to avoid such large 

variation within Category A. The additional criteria may also need clarification to avoid product 

class overlap. Although the intention is that a product qualifies in one category only, it may be 

confusing if they meet the criteria for multiple categories. DOE typically implements product 

classes which are mutually exclusive of one another to set clear boundaries between included and 

excluded products. For example, this could be done by stating a computer meeting multiple 

categories would be only included in the highest letter category it can meet. 

Implementing a similar structure in a rulemaking using all combinations of categories and 

additional product features (such as, graphics processing unit, storage, memory, etc.) could result 

in more than 50 product classes, so it is imperative that the classification system is well 

organized and each class is clearly defined. DOE is evaluating different methods of organizing 

these products to ensure that all necessary features are accounted for, and that product utility is 

not penalized by a more rigorous standard level. 
35

In addition to categories for desktop, integrated desktop, and notebook computers, 

ENERGY STAR Computers V. 5.2 also includes categories for small-scale servers and thin 

clients (as shown in Table 5-3). These products utilize a more simple structure, which has two 

categories and an energy allowance for WOL. This is further refined for workstations, which 

only have a base category and obtain an energy allowance for additional hard drives. DOE sees 

value in a simplistic approach and may consider a similar structure when developing product 

classes for small-scale servers and workstations, if these products are included in scope.

Table 5-3: ENERGY STAR Computers V. 5.2 Categories for Small-scale Servers and Thin 

Clients

Category Description

Small-Scale 

Servers

A Does not meet category B

B

Memory ≥ 1 GB, and

CPU ≥ 1 Physical Cores or CPU ≥ 1 discrete processor

Thin

Clients

A Does not meet category B

B Supports local multimedia encoding/decoding

Item 5-2 DOE requests comment on the categorization criteria for the ENERGY 

STAR Computers V. 5.2 product categories.

Item 5-3 DOE requests comment on the memory, graphics, and storage subcategorization and energy allowances from ENERGY STAR Computers V. 

5.2.

5.1.3 ENERGY STAR Computers V. 6.0

ENERGY STAR Computers V. 6.0 contains six categories for desktop, integrated 

desktop, and notebook computers, shown in Table 5-4 and Table 5-5. Additionally, each product 

with discrete graphics is eligible for one of seven different graphics allowances based on its 

bandwidth speed, as shown in Table 5-6. Allowances are also added for computers with 

switchable graphics processors, Energy-Efficient Ethernet (EEE), high-efficiency power 

supplies, WOL, integrated displays, enhanced performance displays, additional storage, and

memory. 
36

Table 5-4: ENERGY STAR Computers V. 6.0 Base Categories for Desktop and Integrated 

Desktop Computers

Graphics Type Base Category Performance Score* Allowance

kWh

Any 0 P ≤ 3 69

Integrated

I1 3 < P ≤ 6 112

I2 6 < P ≤ 7 120

I3 P > 7 135

Discrete

D1 3 < P ≤ 9 115

D2 P > 9 135

* Performance score (P) = (# CPU cores) × (CPU clock speed in gigahertz)

Table 5-5: ENERGY STAR Computers V. 6.0 Base Categories for Notebook Computers

Graphics Type Base Category Performance Score* Allowance

kWh

Any 0 P ≤ 2 14

Integrated

I1 2 < P ≤ 5.2 22

I2 5.2 < P ≤ 8 24

I3 P > 8 28

Discrete

D1 2 < P ≤ 9 16

D2 P > 9 18

* Performance score (P) = (# CPU cores) × (CPU clock speed in gigahertz)

Table 5-6: ENERGY STAR Computers V. 6.0 Discrete Graphics Allowance

Graphics 

Category GPU Bandwidth (BW)

Desktops 

Allowance 

kWh

Notebooks 

Allowance

kWh

G1 BW ≤ 16 36 14

G2 16 < BW ≤ 32 51 20

G3 32 < BW ≤ 64 64 26

G4 64 < BW ≤ 96 83 32

G5 96 < BW ≤ 128 105 42

G6 BW > 128 (Data Width < 192) 115 48

G7 BW > 128 (Data Width ≥ 192) 130 60

DOE evaluated the ENERGY STAR Computers V. 6.0 product classification structure. 

The performance score (number of cores times clock frequency) is used along with the graphics 
37

capability to determine the category, as seen in Table 5-4. Additionally, DOE is considering the 

expanded graphics categories in Table 5-6 in comparison to the graphics allowances in 

ENERGY STAR Computers V. 5.2. DOE is seeking input on the most appropriate way to 

characterize commercially available GPUs and their associated power consumption.

Typically, ENERGY STAR grants energy allowances based on product features that 

consume more energy while simultaneously increasing functionality. However, EEE, highefficiency power supplies, and switchable graphics processors, are incentivized by offering such 

energy allowances even though they do not increase the energy consumption of the product, and 

in some cases, reduce the energy consumption. DOE will evaluate these features in more detail, 

to determine whether they warrant separate product classes.

In addition to storage and memory, DOE is considering integrated displays and enhanced 

performance displays as features that may merit separate product classes, because these features 

offer an additional utility to the consumer. The display-related features are scaled with the screen 

size in ENERGY STAR Computers V. 6.0 because larger screens typically require more energy. 

DOE is also open to considering other classification criteria and product features which have 

utility to the consumer such that an additional product class should be established.

Item 5-4 DOE requests comment on whether the CPU performance metric 

effectively classifies the performance of a CPU.

Item 5-5 DOE requests comment on the granularity of seven graphics categories 

consistent with the market of available GPUs.

Item 5-6 DOE requests comment on the enhanced performance display and 

integrated display performance features.

Item 5-7 DOE requests comment on the absence of product categories for thin 

clients and small-scale servers.

5.2 Computer Server Product Classes

ENERGY STAR Computer Servers V. 2.0 defines product categories based on form 

factor, creating different classes for pedestal servers, rack servers, blade systems, and multinode servers. Within each of these product categories, ENERGY STAR Computer Servers V. 2.0

accounts for variation in energy consumption and additional functionality by dividing them into 

sub-categories (see Table 5-7). Sub-categories are distinguished by the number of physical CPUs 

as well as criteria for a managed server. Further, ENERGY STAR grants allowances based on 

certain product features such as number of power supplies, additional memory and hard drives, 

and input/output devices. DOE recognizes that using sub-categories is necessary to account for 

variations in power consumption and product features, but may decide to use additional criteria 

for such categories. DOE will perform its own analyses to determine the standard. DOE’s criteria 

to distinguish consumer computer servers will also be considered when determining product 

classes.
38

Table 5-7: ENERGY STAR Computer Servers V. 2.0 Categories

Category

Max Number of 

Installed 

Processors

Managed Server Base Power 

Allowance (W)

A 1 No Max Power A

B 1 Yes Max Power B

C 2 No Max Power C

D 2 Yes Max Power D

Resilient 2 Yes Max Power Resilient

Other possible strategies could include product classes based on application types or 

hardware features such as number of processors, redundancy features or storage capacity. DOE 

may also consider a metric-score based approach, similar to the performance score used in 

ENERGY STAR Computers V. 6.0.

Item 5-8 DOE requests comment on possible strategies for computer server 

product classes. DOE requests comment on possible advantages and 

shortcomings of using the ENERGY STAR Computer Servers V. 2.0 

classification criteria for the purpose of this rulemaking.

5.3 Uninterruptible Power Supplies Product Classes

DOE is considering the adoption of ENERGY STAR UPS V. 1.0’s classification for 

UPSs but will perform its own analyses to determine the standard. The ENERGY STAR UPS V. 

1.0 program sets minimum average efficiency requirements based on the following 

characteristics:

(1) UPS topology: A variety of UPS technologies exist to satisfy user requirements for 

continuity and quality of power. Most consumer UPSs can be classified into three 

basic topologies: VFD, VI and VFI. Each topology offers improved efficiency and 

protection against input power variation respectively. The following are brief 

definitions of these three topologies that DOE is considering to use as the basis for 

UPS product classes in this rulemaking.

(a) A VFD topology, also known as a standby/offline UPS, provides the most basic 

of features such as protection against an input power outage. Because this 

internal power conversion takes place only in the event of an outage, a standby 

UPS is also considered the most efficient. However, a standby UPS is unable to 

protect against sustained dips or surges in input voltage and frequency.

(b) A VI topology, also known as a line interactive UPS, performs all the functions 

of a standby/offline UPS with the added capability of maintaining output power 

in the event of a prolonged under or over-voltage condition in input power. A 

line interactive UPS is unable to correct against variations in input frequency.
39

(c) A VFI topology, also known as an online or double-conversion UPS, is capable 

of protecting a connected device not only against power outages but also against 

all voltage and frequency fluctuations. The topology does this by converting 

input AC power to DC in order to charge the internal battery and then reconverting the battery’s DC voltage to AC using an inverter. Because this 

double-conversion takes place continuously, a VFI UPS is inherently less 

efficient than a VFD or VI unit but provides electrical isolation.

(2) UPS rated output power: Efficiency of a UPS decreases with increasing rated output 

power. ENERGY STAR UPS V. 1.0 therefore provides efficiency allowances for 

UPS in three distinct power ratings:

(a) P ≤ 1500W

(b) 1500W < P ≤ 10,000W

(c) P > 10,000W

(3) UPS output type: UPSs that output DC power replace the output inverter with a 

power supply to achieve the desired DC voltage. As such, different efficiency 

allowances may be required for a DC-output UPS as compared to one with an AC 

output. 

(4) Additional Features: Additional features such as metering and communication 

capability may warrant different product classes. DOE will investigate the energy 

consumption of units with and without these additional features to understand the 

marginal impact on efficiency. 

Table 5-8 and Table 5-9 show ENERGY STAR’s minimum average efficiency 

requirement based on the above product classification for AC and DC output UPSs, respectively.

DOE will not directly use the standard specified in ENERGY STAR, but will consider the 

criteria and classification requirements for its analyses.

Table 5-8: ENERGY STAR UPS V. 1.0 Efficiency Levels for AC-Output UPS

Input Dependency

Rated Output Power VFD VI VFI

P<1500W 0.967

1500W<P<10,000W 0.97 0.967 0.0099 x ln(P) + 0.815

P>10,000W 0.97 0.95 0.0099 x ln(P) + 0.805

P>10,000W

(with Metering and Communication)

0.96 0.94 0.0099 x ln(P) + 0.795
40

Table 5-9: ENERGY STAR UPS V. 1.0 Efficiency Levels for DC-Output UPS

Without Metering and Communication 0.955

With Metering and Communication 0.945

Item 5-9 DOE requests comment on possible advantages and shortcomings of 

using the ENERGY STAR UPS V. 1.0 product classification criteria for the 

purpose of this rulemaking. 

6. MARKET AND TECHNOLOGY ASSESSMENT

The market and technology assessment provides information about the computer systems

industry and the performance attributes of this product. DOE uses this assessment to determine 

product classes and identify potential design options or efficiency levels for each product class.

6.1 Market Assessment

The market assessment identifies computer systems manufacturers, estimates market 

shares and trends, and addresses regulatory and non-regulatory initiatives intended to improve 

the energy efficiency or reduce the energy consumption of computer systems. This allows DOE 

to gather data that can help identify important issues in other phases of its analysis (e.g., potential 

small business impacts, competitive disruptions, and other factors that may arise from enacting 

standards). The market structure data may also be used in the manufacturer impact analysis to 

assess the competitive impact by products and manufacturers.

DOE recognizes that there may be limited market information regarding recent trends of

national shipments, manufacturing costs, channels of distribution, and manufacturers’ market 

shares of computer, computer servers, and UPSs, and therefore encourages interested parties to 

submit data that pertains to these issues and would aid DOE’s understanding of trends in these

markets. This data is important for analyses that determine if energy conservation standards are 

economically justified or will result in significant energy savings.

Stakeholders may submit confidential data to DOE, indicating in writing which data 

should remain confidential. To prevent public disclosure of the data due to actions taken by a 

third party, interested parties providing confidential information to DOE must submit that data 

according to 10 CFR 1004.11. Under 10 CFR 1004.11, any person submitting information that 

he or she believes to be confidential and exempt by law from public disclosure should submit 

two copies. One copy of the document shall include all the information believed to be 

confidential, and the other copy of the document shall have the information believed to be 

confidential deleted. DOE will make its own determination about the confidential status of the 

information and treat it according to its determination. DOE prepares aggregated results from the 

data submitted for use in DOE’s analyses. These aggregated results do not divulge the sensitive 

nature of the individual raw data, but enable other interested parties to review and comment on 

the aggregated dataset. 
41

Item 6-1 DOE requests information that would contribute to the market 

assessment for computers, computer servers, and UPSs that would be covered 

in this rulemaking. DOE particularly seeks information on shipments, trends 

in product feature and efficiency, distribution channels and estimates of 

market shares for the computers, computer servers, and UPSs considered in 

this rulemaking.

6.1.1 Market Assessment for Computers

DOE performed an initial analysis of computer market data to evaluate the number of 

products shipped annually and their market share. DOE’s initial analysis suggests that the overall 

number of desktop, laptop, and tablet computer shipments is expected to experience significant 

growth in the coming years20 (see Figure 6-1). However, a majority of the expected growth is 

due to the increase in tablet computer shipments while desktop and laptop computer shipments 

are expected to level off and experience a slight decrease. However, the U.S. market has 

maintained consistent shipment levels since the emergence of tablet computers in the recent 

years

21

, and still represents a large energy use based on their volume. 

Figure 6-1: Current and Projected Device Shipments by Year

Source: Arthur, Charles. Microsoft threatened as smartphones and tablets rise, Garner warns. The Guardian. 2013.

6.1.2 Market Assessment for Computer Servers

Similarly, DOE analyzed market data for computer servers. This analysis revealed a 

slight global decline in both shipments and revenues between the third quarters of 2012 and 

 

20 Arthur, Charles. Microsoft threatened as smartphones and tables rise, Garner warns. The Guardian. 2013. 

<http://www.theguardian.com/technology/2013/apr/04/microsoft-smartphones-tablets>

21Gartner Says Worldwide PC Shipments in the Third Quarter of 2013 Decline 8.6 Percent. Gartner. 9 October 

2013. <http://www.gartner.com/newsroom/id/2604616>
42

2013. Between these periods, worldwide shipments of computer servers declined by only 0.4 

percent (from 2.27 million to 2.26 million) as illustrated in Figure 6-2, whereas global revenues 

declined by 3.7 percent (from $12,559 million to $12,085 million)22 marking the third 

consecutive quarter of year-over-year revenue decline. The International Data Corporation (IDC)

attributes this decline in part to the anticipation of a forthcoming platform refresh in early 2014, 

but also cites the continued focus of enterprise server customers to use virtualization, 

consolidation and migration alternatives to increase efficiency and lower infrastructure costs as a 

cause of contraction in the market for computer servers.

23

Figure 6-2: Worldwide Quarterly Server Shipments (3Q12 to 3Q13)

Source: IDC Worldwide Quarterly Server Tracker, December 2013.

6.1.3 Market Assessment for Uninterruptible Power Supplies

DOE also analyzed market data for UPS. In 2005, the market value for UPS was 

estimated to be worth $5 billion with the United States comprising half of the total market 

value.

24 The global market for UPS grew to over $8 billion in 2008 led by growth in Asia Pacific 

markets of between 15 percent and 20 percent annually.

25 In contrast, the US market was 

forecast to grow at a rate of only 4 percent annually through 201024. As of 2011, the global UPS 

market was expected to rebound to 2008 levels by as soon as 201225, and to grow to $14 billion 

 

22 Eastwood, M., Scaramella, J., Stalarski, K., and Shirer, M. Worldwide Server Market Revenues Decline -3.7% in 

the Third Quarter as Weak Unix Server Demand Weights on the Market, According to IDC.

23Worldwide Server Market Revenue Decline -6.2% in Second Quarter as Market Demand Remains Weak, 

According to IDC. IDC. 2013 <http://www.idc.com/getdoc.jsp?containerId=prUS24285213>

24 Trends in UPS Systems, Electrical Contractor Magazine, November 2005 (http://www.ecmag.com/section/yourbusiness/trends-ups-systems).

25 UPS Revenues top $7 billion... again, IHS, March 2011 (https://technology.ihs.com/479736/ups-revenues-top-7-

billion-again).
43

by 201726. However, a slowdown in fourth quarter sales of UPS in 2011(as illustrated in Figure 

6-3) led into flat performance in 201227, casting doubt on the market reaching the levels 

previously forecast.

Figure 6-3: World UPS Market Development

Source: IMS Research, February 2012

Growth in the global UPS market is driven in part by increasing virtualization and the

convergence of voice and data networks. Additionally, recognition of the cost of not protecting 

communications infrastructure and IT systems when utility outages do occur are fueling 

additional growth in areas with otherwise unreliable power systems.24, 25

6.2 Technology Assessment for Computers

The technology assessment evaluates all available technology options that may be 

capable of reducing the power consumption of computers. DOE works with stakeholders and 

industry affiliates to develop a comprehensive list of options that include commercially available 

technologies as well as working prototypes. DOE also evaluates manufacturer websites, trade 

publications, and technical journals for additional options. The technology options are used as 

examples of energy saving techniques in the screening and engineering analysis. They provide an 

 

26 Global Uninterruptible Power Supply (UPS) Systems Market to Reach US$14 Billion by 2017, Global Industry 

Analysts, Inc., November 2011 

(http://www.prweb.com/releases/uninterruptible_power/supply_UPS_systems/prweb8953934.htm).

27 UPS Service Market Flat in 2012; First Quarter Indicates a Better 2013, IHS, June 2013 

(https://technology.ihs.com/479688/ups-service-market-flat-in-2012-first-quarter-indicates-a-better-2013).
44

optional avenue to achieve certain energy saving levels but are not mandatory to implement. The 

engineering analysis of these technology options also helps to justify the CSLs which DOE has 

selected. 

Based on an initial review of hardware and software options for computers, DOE has 

identified the following technology options as having potential to improve the efficiency of 

computers. 

6.2.1 Efficient Power Supplies

The internal and external power supply unit (PSU) can consume a significant amount of 

energy as a result of efficiency losses and a low power factor. Efficient PSU designs and power 

factor correction reduce the overall energy consumption of the computer. Voluntary power 

supply standards like ENERGY STAR and the 80 PLUS program28 aim at improving PSU 

energy efficiency by setting voluntary standard limits. The Federal external power supply 

standard implemented by DOE in February 2014 will also contribute to efficiency gains for 

PSUs of notebooks and other computers with external supplies. See 79 FR 7846 (February 10, 

2014).

6.2.2 Efficient Hard Drives

The power consumption of a computer hard drive can be decreased in different ways. 

One option is a hard disk drive (HDD) that has fewer rotations per minute (RPM) than a standard 

HDD. Low RPM HDDs typically sacrifice performance for lower power consumption. This type 

of HDD may also have variable RPM, allowing high-performance tasks to increase the RPM 

(and power consumption) of the drive. 

Another method is to replace or supplement the traditional HDD with a solid-state drive 

(SSD). SSDs operate using flash memory instead of a spinning hard disk and require 

significantly less power. In addition to increases in efficiency, SSDs are faster, more durable, and 

are available in smaller form factors. SSDs can be used as the sole hard drive or in conjunction 

with an HDD for storing the computer OS while the HDD handles other data storage. A system 

with both an SSD and HDD can achieve some of the performance and power savings of SSD 

systems at a lower cost. The difference in cost has prevented SSDs from becoming standard in 

computers, though as technology advances and prices come down they are becoming

increasingly common. There are also hybrid approaches where the portion of the drive accessed 

more frequently is stored as an SSD, and the rest of the drive is stored as an HDD. This allows 

for some energy savings at reduced costs.

 

28 80 PLUS Certified Power Supplies and manufacturers. <www.plugloadsolutions.com/80PlusPowerSupplies.aspx>
45

6.2.3 Energy-Efficient Ethernet

EEE can be used as a method of decreasing the power consumption of Ethernet ports on a 

computer, and is standardized by the Institute of Electrical and Electronics Engineers (IEEE) 

Standard 802.3az.

29 EEE saves energy over standard Ethernet by placing the Ethernet port into a 

low-power state when not in use. EEE also allows energy to be saved by detecting the cable 

length to vary the signal power transmitted over the cable, instead of simply transmitting a signal 

for the maximum rated Ethernet cable length.

6.2.4 Passive Cooling

Cooling is a necessary part of the computer architecture and without an adequate cooling 

system, CPUs and other core components can experience damage from overheating. Lower

power CPUs and SSDs can alleviate the need for high power fans making way for passive 

cooling systems. Splitted-Desktop Systems has demonstrated a technology prototype for cooling 

a CPU using convection airflow with no moving parts, saving energy from fans while 

maintaining comparable cooling performance.

30 This design has form-factor restrictions that may 

limit it to desktop computers.

6.2.5 ACPI-Compatible Devices

Advanced Configuration and Power Interface (ACPI) is a specification for the power 

management of a computer by introducing low power states to the system as a whole, the 

processor, and individual components. While most modern OSs support ACPI functionality, the 

computer’s basic input/output system (BIOS) must be ACPI-compliant in order to experience 

any power reduction. In addition, individual components must be ACPI-compatible to benefit 

from software and firmware power regulation. Manufacturers may therefore decrease the power 

consumption of computers by choosing ACPI-compatible components.

6.2.6 Switchable Graphics

Computers with a discrete GPU devote significantly more power to graphics processing 

than those with a graphics card integrated onto the motherboard. However, discrete graphics 

have higher performance and may be necessary for the computer application. In these cases, 

power can be saved by implementing switchable graphics. During low graphic demand, the 

computer uses the integrated graphics processor to reduce power demands, and switch to the 

discrete graphics card under high graphic demands. 

 

29 Institute of Electrical and Electronics Engineers (IEEE) 802.3az-2010 - Standard for Information technology—

Local and metropolitan area networks—Specific requirements—Part 3: CSMA/CD Access Method and Physical 

Layer Specifications Amendment 5: Media Access Control Parameters, Physical Layers, and Management 

Parameters for Energy-Efficient Ethernet.

30 Kirsch, N. Splitted-Desktop Shows Fanless Sandy Bridge Cooling At IDF 2011. Legit Reviews. September 2011. 

<www.legitreviews.com/splitted-desktop-shows-fanless-sandy-bridge-cooling-at-idf-2011_1710>
46

6.2.7 Dynamic Voltage and Frequency Scaling

A transistor is the fundamental element in the circuitry of a computer, allowing 

components to switch between high and low logic states for computation and memory. The 

switching power of a transistor is proportional to both the clock frequency and the square of the 

supply voltage at the gate. Correspondingly, one method to decrease power consumption in the 

transistor circuitry is to decrease the supply voltage of the chip and the clock speed. An 

additional benefit of decreasing the supply voltage is a decrease in the amount of heat generated 

by the chip, keeping the computer at a more efficient lower temperature. Lowering the voltage 

does not necessarily affect performance on its own, as long as the transistor can handle the lower 

voltage, but oftentimes it can decrease the reliability of the circuit as the gate voltage may 

change between levels at a slower rate. 

To mitigate the reliability risks, the switching frequency of the circuit may be lowered. 

While a decrease in frequency also decreases power consumption, it slows the processing speed 

for lower performance and is generally only used when high performance tasks are not being run. 

This can be done in a dynamic way depending on the processing task at hand. Overall, voltage 

and frequency scaling may be used in any circuitry of the computer, though it is most often 

implemented on the CPU.

6.2.8 Resilient Circuitry

Similar to the reasoning behind dynamic voltage and frequency scaling, the power of 

transistors can be reduced by decreasing the buffer between the supply voltage and the minimum 

voltage for a high logic state. Decreasing this safety band also decreases reliability as it increases 

the possibility for the transistor voltage to be indistinguishable, neither high nor low. Intel has 

designed a method for circuit error correction that recalculates a flagged operation with a slight 

delay.

31 The circuit resiliency allows a smaller voltage buffer margin and lower power 

consumption. This technology may still be in prototype phase.

Item 6-2 DOE requests comment and/or information on the current 

technological status of error-resilient circuitry.

6.2.9 Clock Gating

Clock gating is a method in which the clock signal is deliberately withheld from certain 

components when they are not in use. In a traditional circuit, the clock signal would be received 

by every component regardless of whether a change in state was needed, causing the component 

status to refresh and consume switching power. However, a component with a gated clock does

not receive a signal instructing them to refresh and therefore the transistor remains at the same 

 

31 Hachman, M. Intel’s Power Research: ‘Resilient Circuits’, ‘ProxZzzy’. PCMag.com. March 2010. 

<www.pcmag.com/article2/0,2817,2361563,00.asp>
47

status and does not draw additional power. Depending on the computer’s activity and the 

required componentry, clock gating can have an impact on power consumption.

6.2.10 CPU Utilization Management

When a CPU is not performing any active tasks it is considered to be idle. Generally, the 

more time a CPU spends in idle mode the less power it consumes. To optimize the time spent in 

idle, the CPU may decide to run the clock faster during a task to finish it more quickly and return 

to the idle state. However, the processor will be consuming more power than it would have been 

otherwise while performing the task. This “race-to-sleep” approach may only decrease power 

consumption if the time spent in idle counteracts the additional power used to run the processor 

at a higher voltage and faster frequency, requiring proper utilization management for effective 

implementation.

6.2.11 Suspended State to Flash

Both Intel and Advanced Micro Devices (AMD) have developed technologies to quickly 

resume a computer’s on mode from a low power state. While sleep mode keeps the computer 

state suspended to the memory for quick wake, a lower power hibernation state can be achieved 

by suspending the computer state to the hard drive and powering down the memory. A typical 

hibernation state requires a longer time to resume than a sleep state, but this flash storage quick 

start technology involves suspending the computer state to a high speed SSD, decreasing this 

latency. The SSD does not have to be the main hard drive and may be a small drive working in 

conjunction with a large HDD. This technology allows the computer to be placed in a lower 

power hibernation state with a latency that is less than or equal to a higher power sleep mode. It 

also benefits performance by protecting the computer state in the event of a power failure during 

non-operation and allowing faster resume while using sleep mode.

6.2.12 Internal Network Proxy

As discussed in section 4.1.4, a network proxy allows a computer’s network functions to 

be operated in low power modes. This allows the computer to be put into a low-power state even 

when the computer needs to stay online. It also prevents the computer from being unnecessarily 

woken up in response to a network request that can be handled by the proxy. Overall, the activity 

of an internal network proxy allows the computer to save power by spending a greater amount of 

time in sleep mode instead of on or idle modes.

6.3 Technology Assessment for Computer Servers

Personal computers and computer servers are very similar products because they share 

similar architecture, componentry, and only differ in their intended applications. Computer 

servers are designed for high performance applications and reliability but still require the same 

core componentry as their multi-media based counterparts. Because of these inherent similarities, 

computer servers can benefit from the same technology options as personal computers including:

(1) Efficient power supply unit (section 6.2.1)

(2) Variable speed HDDs and SSDs (section 6.2.2)
48

(3) Dynamic voltage and frequency scaling (section 6.2.7)

(4) Clock gating (section 6.2.9)

In addition to these shared technology options, computer servers can also benefit from the 

following design options. 

6.3.1 Fan Speed Control Algorithms

Equation 6-1: Relationship between power consumed by fan and fan speed

 

 

Where:

 : Power consumed by fan

 : : Instantaneous speed of fan

The power consumed by fans has a cubic relationship with fan speed. Therefore, a creative fan 

speed control scheme32 can save a significant amount of energy consumption by lowering the fan 

speed.33

6.3.2 Management Interface Low-Power States

When not in active use, the server management interface card can be induced to a lower 

power state through power and/or clock gating non-essential components of the management 

interface, similar to the C-states in the microprocessor.

6.4 Technology Assessment for Uninterruptible Power Supplies

6.4.1 Semiconductor Improvements

DOE’s preliminary review of existing and forthcoming UPS technologies has shown 

improved energy consumption levels compared to traditional designs. Customer demand for 

increased reliability and reduced total cost of ownership (TCO) has led manufacturers to design 

efficient UPSs with more robust components. Improvements in semiconductor technology has 

paved the way for insulated gate bipolar transistors (IGBT) that offer increased current carrying 

 

32 Kim, J., et al. Global Fan Speed control considering Non-Ideal Temperature Measurements in Enterprise Servers.

EDAA. 2014.

33 Shin, D., et al., Energy-optimal dynamic thermal management for green computing in Proc. ICCAD, 2009.
49

capability, faster switching speeds, smaller footprint and reduced overall cost. This technology is 

poised to replace inefficient silicon controlled rectifier (SCR) switches traditionally used.34

6.4.2 Digital Signal Processing and Space Vector Modulation 

Digital signal processing (DSP), space vector modulation (SVM) and fast switching 

transistors in UPSs now allow for intelligent switching that can adapt faster to changing input 

and output conditions.35 This allows UPSs to reduce inefficient switching modes with lighter 

loads – an operating point where UPSs are known to be sub-optimal.

6.4.3 Transformer-less UPS Topologies

Transformer-less UPS topologies which are now possible also due to DSP and IGBT, 

reduce these harmonic distortions further while improving overall UPS energy consumption by 

removing the line-frequency transformer popular in conventional designs. Additionally, 

transformer-less UPS designs improve input power factor and reduce weight and overall 

footprint – all of which may be a cost burden for consumers.36

Powering a device using a UPS is inherently less efficient when compared to running the 

same product directly from AC mains. This is primarily due to the additional power conversion 

processes involved. However, most UPSs, depending on their construction, will condition, 

isolate and filter adverse currents which reduce the burden on the AC mains network.37 This 

additional utility may outweigh the inefficiencies of a UPS by reducing the cost burden of 

conditioning a noisy power line for sensitive digital electronics in the vicinity.

Item 6-3 DOE welcomes comments on the preliminary technology options for 

computer systems identified in this section and whether there are other 

technology options it should consider. In commenting on technology options, 

please discuss their impacts, if any, on safety, performance, and user utility, 

as well as cost of the technology options.

7. SCREENING ANALYSIS

The purpose of the screening analysis is to screen out technology options that DOE will 

not consider in its potential energy conservation standard for computer systems. At the outset, 

DOE develops a list of technology options for consideration through its own research and in 

consultation with interested parties. Development of the list is based on the technologies 

 

34 Richard L. Sawyer, Making Large UPS Systems More Efficient, APC White Paper #108, 2006.

35 Trends in UPS Systems, Electrical Contractor Magazine, November 2005.

36 Ian F Bitterlin, Benefits of transformer-free UPS topology: myth or reality?, Chloride UPS Systems, July 2010. 

37 Yam Hong, Future Trends: The Transformerless UPS, Schneider Electric.
50

described in sections 6.2 and 6.3. The identified candidate technology options encompass all 

those technologies that may improve energy efficiency. 

DOE then reviews each technology option considering the following four criteria, as 

provided in sections 4(a)(4) and 5(b) of Procedures, Interpretations, and Policies for 

Consideration of New or Revised Energy Conservation Standards for Consumer Products (see 

10 CFR part 430, subpart C, appendix A):

(1) Technological feasibility. DOE does not further consider technologies that are not 

incorporated in commercially available product or in working prototypes.

(2) Practicability to manufacture, install, and service. If DOE determines that mass 

production of a technology and reliable installation and servicing of the technology 

could not be achieved on the scale necessary to serve the relevant market by the 

time of the effective date of the standard, then it does not consider that technology 

further.

(3) Adverse impacts on product or equipment utility or availability. If DOE determines 

that a technology will have a significant adverse impact on the utility of the product

to significant subgroups of consumers, or result in the unavailability of any covered 

product type with performance characteristics (including reliability), features, size, 

capacities, and volumes that are substantially the same as products generally 

available in the United States at the time, it does not consider that technology 

further.

(4) Adverse impacts on health or safety. If DOE determines that a technology will have 

significant adverse impacts on health or safety, it does not consider that technology 

further.

DOE will fully document the reasons for eliminating any technology options during the 

screening analysis and solicit interested parties’ comment. The remaining design options are 

considered further in the engineering analysis (section 8).

Item 7-1 Are there any technologies, including those listed in sections 6.2, 6.3, 

and 6.4 that DOE should not consider because of any of the four screening 

criteria? If so, which screening criteria apply to the cited technology or 

technologies? 

8. ENGINEERING ANALYSIS

After conducting the screening analysis, DOE performs an engineering analysis based on 

the remaining design options that would improve the efficiency of computer systems. This 

section provides an overview of the engineering analysis, and discusses baseline models, DOE’s 

proposed approach for determining the cost-efficiency relationship, efficiency levels, proprietary 

designs, and cumulative regulatory burdens that might affect the engineering analysis. 
51

8.1 Engineering Analysis Overview

The purpose of the engineering analysis is to determine the relationship between 

manufacturer selling price (MSP) and the product’s energy efficiency (power consumption). In 

determining the cost-efficiency relationship, DOE estimates the increase in MSP (which includes 

manufacturing cost and manufacturer markups) associated with design changes that increase the 

efficiency (decrease power consumption) of computer systems relative to the baseline models. 

As a preliminary step in this analysis, DOE may determine an appropriate subset of 

representative product classes to analyze. DOE will extrapolate the results of this analysis to the 

remaining product classes. Typically, each representative product class would represent the 

majority of the shipments in its category. The number of representative product classes depends

on the availability of data that allows for developing appropriate relationships between the 

engineering analysis results of the representative product class and the other product classes not 

directly analyzed. For each representative product class, DOE may analyze a subset of 

representative units.

For the engineering analysis, DOE examines incremental changes in MSP associated with 

increases in the product’s efficiency. DOE intends to use publicly available data from 

manufacturer websites and catalogs for computer systems’ in the market to categorize 

relationships between efficiency and technological options. DOE also uses this information to 

select representative units in each product class. DOE focuses its analyses on these representative 

units.

Item 8-1 DOE encourages interested parties to submit data that will improve 

DOE’s understanding of computer systems’ performance and associated 

costs.

DOE has two options for conducting the engineering analysis:

(1) Design-option approach. Report the incremental costs of adding design options or 

combinations of design options to a baseline model.

38 This cost includes but is not 

limited to incremental cost of changes in material, labor, shipping, and overhead 

from the baseline

(2) Efficiency level approach. Report relative costs of achieving improvements in 

energy efficiency at incremental efficiency levels over baseline, including those 

efficiency levels that include the maximum efficiency improvements that are 

technologically feasible (max-tech). All models of varying efficiency for a given 

representative unit should be as similar as possible to be comparable, and ideally 

differ only in efficiency. 

 

38 Typically represents products with the lowest efficiency on the market.
52

For each representative unit, DOE identifies and evaluates commercially available 

products that incorporate design options that improve efficiency. The engineering analysis will 

also identify the highest efficiency that is technologically feasible (i.e., the max-tech model). 

DOE may determine the max-tech model by investigating the existence of any working computer

system prototypes with higher efficiency than those commercially available. DOE examines only 

commercially available products; therefore, this approach may not provide information about the 

most efficient designs.

8.2 Engineering Analysis Methodology

DOE plans to purchase, test, and reverse engineer the representative units within each 

representative product class. DOE will conduct testing according to the appropriate DOE test 

procedure, which it will be developing concurrently (see section 4). The reverse engineering will 

include a physical teardown of the representative unit in which DOE will disassemble and 

inventory the product, identify the design options and technology changes, and construct a bill of 

materials (BOM) and labor cost estimate for each computer system. DOE may supplement the 

findings from its tests and teardowns through: 

(1) A review of data collected from manufacturers about prices, efficiencies, and other 

features of various computer system models, and

(2) Interviews with manufacturers about the techniques and associated costs used to 

improve efficiency.

In addition, DOE will use the cost data generated by the engineering analysis in the 

manufacturer impact analysis (see section 15).

DOE will also develop a cost model as part of the engineering analysis. The cost model 

will use the BOM generated from either a design-option or an efficiency level approach to 

estimate the product costs (i.e., MSP) for each representative unit at each efficiency level 

considered. The proposed approach will enable DOE to characterize the cost-efficiency 

relationship for computer systems across the entire efficiency range for all product classes. DOE 

will maintain the confidentiality of proprietary data while allowing the public to examine the cost 

and design assumptions that underlie the cost-efficiency estimates.

The proposed approach will enable DOE to characterize the cost-efficiency relationship 

for computer systems across the entire efficiency range for all product classes. DOE will 

maintain the confidentiality of proprietary data while allowing the public to examine the cost and 

design assumptions that underlie the cost-efficiency estimates.

8.2.1 Representative Units and Baseline Models

The computer systems product classes cover a range of form factors and performance 

capabilities. To evaluate the efficiency and design within product classes, DOE will select 

representative models for each product class for the engineering analysis. These models may 

represent common performance characteristics and through this analysis may be related to other 

models on the market.
53

To analyze technology options for energy efficiency improvements, DOE will define a 

representative baseline model for each representative unit. The baseline model should represent 

the characteristics of computer systems for their respective product class. DOE will evaluate 

selection of the baseline model at the bottom-of-market efficiency level or the minimum level 

commonly available for computer systems. Selection of the baseline model for each 

representative unit will consider the product’s features and performance characteristics.

8.3 Proprietary Designs

DOE will consider in its engineering and economic analyses all design options that are 

commercially available or present in a working prototype, including proprietary designs and 

technologies. However, DOE will consider a proprietary design in the subsequent analyses only 

if the achieved efficiency level can also be reached using other non-proprietary design options. If 

the proprietary design is the only approach available to achieve a given efficiency level, then 

DOE will reject that efficiency level, as the analytical results would appear to favor one 

manufacturer over others.

DOE is sensitive to manufacturer concerns regarding proprietary designs and will make 

provisions to maintain the confidentiality of proprietary data submitted by manufacturers or 

discussed during manufacturer interviews. Materials provided to Lawrence Berkeley National 

Laboratory (LBNL) or Navigant Consulting, Inc. (NCI), DOE contractors for this rulemaking, 

are generally subject to the terms of the applicable agreement under which those materials are 

submitted. In the case of materials provided to LBNL or NCI in the context of a DOE 

rulemaking and subject to a non-disclosure agreement, those materials are generally not shared 

with DOE, apart from aggregated data that do not identify particular submitters. These materials 

may also be subject to a variety of laws and regulations governing the disclosure of federal 

agency information. Information submitted to DOE will be protected in accordance with all 

applicable federal laws, rules, or regulations, including but not limited to the Trade Secrets Act, 

18 U.S.C. 1905, and the Freedom of Information Act (FOIA), 5 U.S.C. 552, and DOE’s 

implementing regulations at 10 CFR 1004.

8.4 Efficiency Levels 

For each of the representative units, DOE will undertake analyses to determine potential 

efficiency levels relative to the baseline case and seek to develop incremental cost data at each of 

these levels. 

To establish the efficiency levels DOE intends to consider, DOE will analyze the design 

changes and costs associated with improving efficiency from the baseline through the max-tech 

model. This will include considering the design options identified in the screening analysis. DOE 

also intends to establish the range of efficiencies currently available on the market. DOE will use 

these data to categorize relationships between efficiency and technological options where the 

technological options used can be identified.

DOE notes that some of the design options that have met the screening criteria (i.e., 

passed the screening analysis) may be working prototypes that are not yet commercially 

available and, therefore, would not be found in today’s available maximum efficiency products.
54

8.5 Outside Regulatory Changes Affecting the Engineering Analysis

In conducting an engineering analysis, DOE takes into consideration the effects of other 

DOE energy conservation standards and regulatory changes outside DOE’s statutory energy 

conservation standards rulemaking process that can affect the manufacturers of the covered 

product. Some regulatory changes can also affect the efficiency or energy consumption of 

computer systems covered in this rulemaking. DOE will attempt to identify all such outside 

engineering issues that could affect the engineering analysis. The consideration of these issues is 

closely related to the cumulative regulatory burden assessment that DOE will carry out as part of 

the manufacturer impact analysis (see section 15).

9. MARKUPS ANALYSIS

DOE uses manufacturer-to-consumer markups to convert the MSP values, obtained from 

the engineering analysis, to consumer purchase prices, which are then used in the later analyses. 

The manufacturer-to-consumer markups are in addition to the markups on production costs that 

DOE uses in estimating manufacturer selling price in the engineering analysis. Consumer

purchase prices are needed for the baseline efficiency level and all other efficiency levels under 

consideration. To quantify these markups, DOE will collect data on existing prices in the market 

(e.g., purchased data sets or distributor Internet sites), where collecting such data is possible and 

produces meaningful results.

To develop markups, DOE must identify distribution channels (i.e., how the product is 

distributed from the manufacturer to the user). Once it establishes proper distribution channels 

for each of the product classes, DOE will estimate how products are marked up in the 

distribution chain from the manufacturer to the user.

DOE will determine an average manufacturer markup by examining the annual U.S. 

Securities and Exchange Commission (SEC) 10-K reports39 filed by publicly traded 

manufacturers of appliances whose product range includes computer systems. DOE will 

determine an average retailer markup by analyzing both economic Census data from the U.S. 

Census Bureau40 and the annual SEC 10-K reports filed by publicly traded retailers. 

In addition to developing manufacturer and retailer markups, DOE will develop and 

include sales taxes to calculate appliance retail prices. DOE will use an Internet source, the Sales 

Tax Clearinghouse41, to calculate applicable sales taxes.

DOE intends to develop baseline and incremental markups for computer systems. 

Baseline markups are cost multipliers applied to the MSP of baseline product, while the 

 

39 10-K reports are available at: <http://www.sec.gov/index.htm>

40 U.S. Census Bureau <http://www.census.gov/econ/census/>

41 Sales Tax Clearinghouse <http://www.thestc.com/>
55

incremental markups are cost multipliers applied to the incremental cost change in the MSP of 

the higher-efficiency product. Through the markups analysis, DOE will generate end-user prices 

for each product efficiency level that DOE considers, assuming that each level represents a new 

minimum efficiency standard. DOE will make this assumption to capture the effect on retail 

prices that may be produced by manufacturers’ higher production volumes of more efficient 

products as required by the standard. DOE’s approach for estimating the markup multipliers will 

depend on the specific distribution channel traced by the product (from the manufacturer to the 

end user).

Item 9-1 DOE seeks suggestions and comments concerning its proposed 

approach to developing estimates of markups.

10. ENERGY USE ANALYSIS

The purpose of the energy-use analysis is to identify how products are used by 

consumers, and thereby determine the energy savings potential of energy efficiency 

improvements. DOE determines the energy consumption of computer systems through the rated 

power and the way consumers use the products (i.e., operating hours per year in various modes 

of operation). This analysis, which is meant to represent typical energy consumption in the field, 

is an input to future analyses to establish the savings in consumer operating costs at various 

product efficiency levels. 

As discussed in section 3, ENERGY STAR Computers V. 6.0 uses an AEC metric that 

estimates the amount of energy a computer will use in one year based on a weighted average of 

measured power consumption values in each mode of operation. It includes mode weightings 

based on a 2010 usage profile study by Ecma International. DOE is considering a test procedure 

with a similar metric. For computer servers, DOE is considering an idle mode power test only, 

which can be converted to an annual energy consumption based on assumed product utilization. 

For UPS, DOE is considering a similar metric to ENERGY STAR UPS V. 1.0. The metrics

proposed for development as part of the test procedures in this rulemaking will contribute to the 

energy use analysis by characterizing the yearly amount of energy consumed by a given unit. In 

addition to characterizing the energy use of individual models for this energy use analysis, DOE 

plans to investigate the average AEC for different product classes and estimate the share of each 

product class in the current market and installed base. Because the energy use of computer 

systems can vary greatly based on different usage patterns, DOE will conduct further research 

and utilize additional data to establish a range of energy use for computer systems.

The energy use analysis will allow DOE to correlate the price distribution from the 

engineering and markups analyses with an annual energy usage distribution for different product 

classes, as well as to support characterization of the impacts of more efficient designs. The 

results of this analysis are used as inputs to the LCC, PBP, NIA, and other downstream analyses.
56

Item 10-1 DOE seeks comments on its proposed approach for specifying typical 

annual energy consumption. Most importantly, DOE is interested in sources 

of data that can assist in characterizing the annual energy consumption of 

computer systems.

Item 10-2 DOE welcomes input on data sources that it can use to characterize the 

variability in annual energy consumption for computer systems in the field. 

DOE is particularly interested in field monitoring studies and data.

11. LIFE-CYCLE COST AND PAYBACK PERIOD ANALYSES

DOE will conduct an LCC analysis to evaluate the economic impacts of energy 

conservation standards developed for computer systems on users. The effect of standards 

includes a change in operating cost (usually decreased) and a change in purchase cost (usually 

increased). The analysis uses two metrics, LCC and PBP, for each representative unit to 

determine the effect of the standards on consumers:

 Life-cycle cost. The total consumer cost over the life of the product is the sum of 

installed costs (purchase and installation costs) and operating costs (energy, maintenance, 

and repair costs as applicable). Future operating costs are discounted to the time of 

purchase and summed over the lifetime of the product.

 Payback period. Payback period is the estimated amount of time (in years) it would take 

consumers to recover the higher purchase price of a more efficient product through lower 

operating costs.

11.1 Approach

Inputs for the LCC analysis are estimated from the best available data for the market. 

Where possible, DOE uses a range of values for each input (for example, the product lifetime, 

which can vary over a wide range).42 DOE will perform the LCC analysis in the form of Monte 

Carlo simulations in which certain inputs are provided as a range of values and probability 

distributions to model both the uncertainty and variability in the inputs. The Monte Carlo 

approach provides a significant advantage over alternative approaches (e.g., an approach using 

typical or average values to characterize inputs) because it identifies the percentages of 

consumers benefiting from or being impacted by a prospective standard. The results of the LCC 

analysis are presented in the form of:

(1) Mean LCC savings; 

 

42 DOE notes that in some cases, data are available for generally accepted representative values within the industry 

rather than a range of values. Calculations based on representative values yield average or representative values for 

the LCC and PBP outputs. 
57

(2) Percentages of consumers experiencing net savings, net cost, and no impact in 

LCC; and

(3) Median PBP.

For each representative unit, DOE develops an LCC and PBP model that incorporates 

both Monte Carlo simulation and probability distributions. Each Monte Carlo simulation would 

typically consist of 10,000 LCC and PBP calculations.43 The model will perform each 

calculation using input values sampled from probability distributions where possible, or 

characterized using single-point values in other cases. The analysis results are a distribution of 

10,000 data points showing the range of LCC savings and PBPs for a given efficiency level 

relative to the baseline level.

DOE expects to use probability distributions to characterize most of the operating cost 

inputs to the LCC and PBP analyses, including product lifetime and consumer discount rates. 

DOE expects to use a combination of data to establish the annual energy consumption of each 

product class, characterized using sales-weighted probability distributions. The LCC and PBP 

analysis will capture the regional variability in electricity prices and sales taxes. Depending on 

the available data, DOE expects to use point values to characterize other LCC inputs, such as the 

manufacturer markup. To estimate the percentage of users that would be affected by a particular 

standard level, DOE takes into account the full range of product efficiencies that users purchase 

under the base case (i.e., the case without new energy conservation standards). By accounting for 

users who already purchase more efficient products, DOE avoids overstating the potential 

benefits from standards.

In addition to the aforementioned cost inputs, DOE will use the cost-efficiency 

relationships obtained from the engineering analysis and the energy consumption values obtained 

from the energy use analysis. 

DOE will determine as part of the LCC and PBP analyses whether there may be a 

rebound (or “take back”) effect associated with more efficient computer systems. The “takeback” in energy consumption associated with the rebound effect typically involves greater use 

that can result from increases in energy efficiency and the associated reduction in operating 

costs. The rebound effect assumes that consumers will increase their overall annual usage of a 

more efficient product, thereby decreasing their overall annual savings.

Based on the results of the LCC analysis, DOE would select candidate standard levels 

(CSLs) for the Preliminary Analysis. The range of CSLs typically includes the efficiency level 

with the minimum LCC, the highest efficiency level that is technologically feasible, and other 

intermediate levels.

 

43 DOE typically chooses 10,000 iterations to ensure the LCC results are representative of the input probability 

distributions.
58

The following sections discuss the methodologies DOE plans to use to develop several of 

the inputs to the LCC and PBP analysis, including (1) electricity prices; (2) maintenance, repair, 

and installation costs; (3) product lifetimes; and (4) discount rates. Other inputs to the LCC and 

PBP analysis (manufacturer costs, annual energy consumption, and markups for the 

determination of consumer retail prices) were discussed previously.

DOE also performs an analysis to determine whether the 3-year rebuttable presumption 

of economic justification applies (i.e.,, whether the additional cost of purchasing a product that 

meets the standard level would be less than three times the value of the energy savings in the first 

year.). (42 U.S.C. 6295(o)(2)(B)(iii)) To determine the rebuttable-presumption PBP, DOE would 

determine the value of the first year’s energy savings by calculating the quantity of those savings 

in accordance with DOE’s test procedure. DOE determines whether selected CSLs are 

economically justified through an analysis of the economic impacts of increased efficiency 

pursuant to section 325(o)(2)(B)(i) of EPCA. (42 U.S.C. 6295(o)(2)(B)(i))

In preparing a NOPR, DOE carefully reviews all the comments it receives on the 

Preliminary Analysis LCC analysis, makes any necessary revisions to the analysis, and if 

necessary evaluates additional parameters not included in the Preliminary Analysis.

Item 11-1 DOE seeks comments on its proposed approach of using probability 

distributions and Monte Carlo simulation to conduct the LCC and PBP 

analysis.

Item 11-2 DOE requests data from stakeholders to characterize the current mix of 

computer system efficiencies in the market.

11.2 Electricity Prices

DOE expects to estimate average electricity prices using Energy Information 

Administration (EIA) data covering the geographic areas outlined in EIA’s Residential Energy 

Consumption Survey. To calculate electricity prices for residential and commercial consumers in 

each of these geographic areas, DOE will use information provided by electric utilities as 

summarized in the most recent EIA Form 861 data.44 These data, which cover the residential, 

commercial, and industrial sectors for every utility serving final customers, are published 

annually and include annual electricity sales in kWh, revenues from electricity sales, and number 

of customers. DOE’s calculation of an average electricity price proceeds in two steps: (1) for 

each utility, estimate an average residential and commercial price by dividing revenues by sales; 

and (2) calculate a regional average price, weighting each utility that has customers in a region 

by the number of residential and commercial customers served in that region.

 

44 EIA Form 861 data available at <www.eia.doe.gov/cneaf/electricity/page/eia861.html>
59

In its LCC analysis DOE uses projections of national average electricity prices to 

residential and commercial consumers to estimate future energy prices. DOE uses the most 

recently available edition of EIA’s Annual Energy Outlook (AEO) as the default source of 

projections for future energy prices.

Item 11-3 DOE seeks comments on the planned approach for estimating current 

and forecasted energy prices.

11.3 Maintenance, Repair, and Installation Costs

DOE will consider any expected changes to maintenance, repair, and installation costs for 

computer systems subject to new standards. Typically, small incremental changes in product 

efficiency incur little or no change in repair and maintenance costs over baseline products. 

Products having efficiencies that are significantly higher than the baseline are more likely to 

incur increased repair and maintenance costs, because such products are more likely to 

incorporate technologies that are not widely available. DOE will use input from manufacturers 

and other stakeholders to develop appropriate repair and maintenance cost estimates, as 

necessary.

With regard to installation costs, unless the increased efficiency levels considered for this 

rulemaking result in significantly larger or heavier products, DOE expects that more efficient 

computer systems will incur no increased installation costs.

Item 11-4 DOE seeks comments on the merits of its proposed analytical 

assumption that changes in maintenance, repair, and installation costs will be 

negligible for more-efficient computer systems. If that assumption is incorrect, 

DOE is interested in the reasons why this is so and in specific ways to correct 

that assumption.

11.4 Product Lifetimes

The product lifetime is the age at which a product is retired from service. DOE will 

characterize computer system survival functions using Weibull distributions. In addition, DOE 

plans to use literature sources, industry experts, and input from manufacturers and other 

interested parties to determine a range for the lifetime of computer systems.

Item 11-5 DOE seeks comments on appropriate product lifetimes for computer 

systems. Specifically, DOE seeks data sources for establishing product 

lifetimes.

11.5 Discount Rates

The calculation of LCC requires the use of an appropriate discount rate. DOE uses a 

discount rate to determine the present value of lifetime operating expenses. The discount rate 
60

used in the LCC analysis represents the rate from an individual consumer’s perspective. For both 

residential and commercial consumers of computer systems, DOE plans to use estimates of the 

interest or “finance cost” to purchase residential or commercial products. For residential 

consumers, the finance cost of raising funds to purchase products can be interpreted as (1) the 

financial cost of any debt incurred to purchase products (principally interest charges on debt), or 

(2) the opportunity cost of any equity used to purchase products (principally interest earnings on 

household equity). Household equity is represented by holdings in assets such as stocks and 

bonds, as well as the return on homeowner equity. Much of the data required for determining the 

cost of debt and equity comes from the Federal Reserve Board’s triennial Survey of Consumer 

Finances.

45 For commercial consumers, DOE will derive the discount rates by estimating the 

capital costs for companies that purchase computer systems. The cost of capital is commonly 

used to estimate the present value of cash flows to be derived from a typical company project or 

investment. Most companies use both debt and equity capital to fund investments, so the cost of 

capital is the weighted-average cost of equity and debt financing, which is referred to as the 

weighted-average cost of capital.

Item 11-6 DOE seeks comments on its planned approach for estimating discount 

rates for residential and commercial consumers.

11.6 Energy Efficiency in the Base Case 

To estimate the share of consumers affected by a standard at a particular efficiency level, 

DOE’s LCC and PBP analysis considers the projected distribution (i.e., market shares) of 

product efficiencies that consumers will purchase in the first compliance year under the base case 

(the case without amended energy conservation standards). DOE requests market-share 

efficiency data (i.e., data on the distribution of shipments by efficiency) for the product classes of 

computer systems.

Forecasted market shares will use available data on recent market trends in computer 

system efficiency and will take into account the potential impacts of other programs or policies 

(such as ENERGY STAR, consumer rebate programs or State tax credits to consumers for the 

purchase more efficient products, and manufacturer tax credits that encourage the production of 

more efficient products) that may affect the demand for more efficient computer systems.

Item 11-7 DOE seeks comments on computer system efficiency in the base case, 

historical efficiency data on computer systems, and projected trends in 

computer system efficiency.

 

45Board of Governors of the Federal Reserve System: Survey of Consumer Finances

<http://www.federalreserve.gov/econresdata/scf/scfindex.htm>
61

12. SHIPMENTS ANALYSIS

DOE forecasts product shipments to calculate the national impacts of standards on energy

consumption, NPV, and future manufacturer cash flows. DOE plans to develop shipments 

projections based on analysis of the key market drivers for computer systems. DOE typically 

projects shipments for a 30-year period beginning with the expected compliance date of any 

standards.

12.1 Base-Case Forecast

To evaluate the various impacts of standards, DOE must develop a base-case projection 

against which to compare projections for higher efficiency levels. The base-case projection is 

designed to depict what will happen to energy consumption and energy costs over time if DOE 

does not adopt new energy conservation standards for the product covered under this rulemaking. 

In determining the base-case projection, DOE will consider historical shipments, the mix of 

efficiencies sold in the absence of standards, and how that mix might change over time, for 

instance in response to known voluntary or incentive-based programs such as ENERGY STAR. 

For these purposes, DOE needs data on historical shipments and the market shares of the 

different efficiency levels offered in each product class. Furthermore, DOE also looks at market 

and industry reports on expected market trends to better understand future product shipments. 

Item 12-1 DOE seeks historical shipments data and reports on future market 

trends from stakeholders. If such data are provided, DOE requests market 

share data showing the percentage of computer system shipments of different 

efficiencies and product classes.

12.2 Impact of Standards on Product Shipments

After developing the base-case projection, DOE will develop a set of shipment 

projections for each product class and each set of standards analyzed, also known as standardscase projections. Standards-case projections are derived using the same datasets as base-case 

projections; however, because the standards-case projections take into account the increase in 

purchase price and the decrease in operating costs caused by standards, projected shipments may 

deviate from the base case. The magnitude of the difference between the standards-case and 

base-case shipment projections depends on the estimated purchase price increase as well as the 

operating cost savings caused by the standard. DOE plans to assess whether the purchase price or 

the operating cost will have a greater impact on computer system purchase decisions; therefore, 

standards case projections may show a change in shipments relative to the base case. These 

standards-case projections will be used to evaluate the impacts of standards on shipments.

DOE’s past standards analyses have attempted to quantify the sensitivity of shipments to 

increased purchase price and operating cost savings, as well as to changes in household income. 

DOE has conducted literature reviews and analyses of historical appliance price and efficiency 

data to develop sensitivities. DOE will attempt to develop purchase price and operating cost 

sensitivities for computer systems. If the data required to develop those sensitivities are 
62

unavailable, DOE will consider modeling standards-case shipments forecasts using scenarios 

(i.e., specified impacts to product shipments).

Market-pull programs, such as ENERGY STAR, consumer rebate programs that 

encourage the purchase of more efficient products, and manufacturer tax credits that encourage 

the production of more efficient products, also affect forecasts of standards-case shipments. To 

the extent that such programs exist, DOE will consider their impact on the forecast of both basecase and standards-case shipments.

Item 12-2 As part of the preliminary manufacturer impact analysis, DOE seeks 

input from manufacturers on the potential impact of new energy conservation 

standards on computer system shipments. DOE also seeks input from other 

stakeholders on the potential impact of standards on product shipments.

Item 12-3 DOE also requests input on any current market-pull programs that 

promote the adoption of more efficient computer systems.

13. NATIONAL IMPACT ANALYSIS

The NIA assesses the aggregate impacts of potential conservation standards at the 

national level. Impacts that DOE will report include the NES from potential computer systems 

standards (i.e., the cumulative incremental energy savings from computer system efficiency 

standards) and the NPV of the total user benefits.

13.1 Energy Efficiency Trends

A key component of DOE’s estimates of NES and NPV are the product energy 

efficiencies projected over time, for the base case (without new standards) and for each of the 

standards cases. To develop the various standards cases, DOE plans to develop market-share 

efficiency data (i.e., data on the distribution of product shipments by efficiency) for the computer

system product classes DOE is considering. To estimate the impact that standards may have in 

the year compliance becomes required, DOE has used “roll-up” and/or “shift” scenarios in its 

past standards rulemakings. DOE will evaluate whether one of these approaches is more 

reasonable for computer systems. 

Under the roll-up scenario, DOE assumes (1) product efficiencies in the base case that do 

not meet the standard level under consideration would roll up to meet the new standard level; and 

(2) product shipments at efficiencies above the standard level under consideration would not be 

affected.

Under the shift scenario, DOE retains the pattern of the base-case efficiency distribution 

but re-orients the distribution at and above the new energy conservation standard. After DOE 

establishes the average efficiency for the assumed effective date of a standard, it can estimate 

future efficiency by using the same rate of projected efficiency growth as for the base-case 

efficiency trend. 
63

Item 13-1 DOE seeks comments on the use of the “roll-up” and “shift” efficiency 

scenarios to characterize the impact that potential standards would have on 

the product efficiency distributions. 

13.2 National Energy Savings

DOE intends to calculate national computer system energy consumption for each year 

beginning with the expected compliance date of any standards. It will calculate national 

computer system energy consumption for the base cases and each standard level analyzed, and 

the energy savings will be calculated as the difference in energy consumption between the base 

case and the standards cases. DOE plans to perform this calculation through the use of a 

spreadsheet model that effectively accounts for the stock of products affected by standards.46 The 

energy savings are measured over the entire lifetime of products purchased in the 30-year 

projection period.47

DOE intends to consider whether there may be a rebound effect associated with more 

efficient computer systems in its determination of NES. Increased equipment utilization may 

result from an increase in energy efficiency. If data indicate that there may be a rebound effect 

and the data are sufficient to allow quantification of this effect for computer systems, DOE will 

account for the rebound effect in its calculation of NES.

DOE has historically presented NES in terms of primary energy savings. In response to 

the recommendations of a committee on “Point-of-Use and Full-Fuel-Cycle Measurement 

Approaches to Energy Efficiency Standards” appointed by the National Academy of Science, 

DOE announced its intention to use full-fuel-cycle (FFC) measures of energy use and 

greenhouse gas and other emissions in the national impact analyses and emissions analyses 

included in future energy conservation standards rulemakings. 76 FR 51281 (August 18, 2011). 

After evaluating the approaches discussed in the August 18, 2011 notice, DOE published a 

statement of amended policy in the Federal Register in which DOE explained its determination 

that NEMS is the most appropriate tool for its FFC analysis and its intention to use NEMS for 

that purpose. 77 FR 49701 (August 17, 2012). The method used to derive the FFC multipliers 

will be described in the preliminary TSD. 

13.3 Net Present Value

To develop the national NPV of user benefits from potential standards, DOE must 

calculate annual energy expenditures and annual product expenditures for the base case and the 

 

46 Several examples of NES spreadsheet models from previous rulemakings can be found on DOE’s website at: 

<http://www.eere.energy.gov/buildings/appliance_standards/> 

47 In the past DOE presented energy savings results for only the 30-year period that begins in the year of 

compliance. In the calculation of economic impacts, however, DOE considered operating cost savings measured 

over the entire lifetime of products purchased in the 30-year period. DOE has chosen to modify its presentation of 

national energy savings to be consistent with the approach used for its national economic analysis.
64

standards cases. DOE calculates annual energy expenditures based on AEC by incorporating 

projected energy prices, using the projections of shipments and average energy efficiency 

described in section 12. DOE calculates annual product expenditures by multiplying the price per 

unit by the number of projected shipments. The difference each year between energy bill savings 

and increased product expenditures is the net savings (if positive) or net costs (if negative). DOE 

discounts those annual values to the present time and sums them to obtain a NPV.

Consistent with guidelines set by the U.S. Office of Management and Budget (OMB), 

DOE will conduct two NPV calculations, one using a real discount rate of 3-percent and the 

other using a real discount rate of 7-percent (OMB, Circular A-4: Regulatory Analysis) 

(September 17, 2003). The discount rates for the determination of NPV differ from the discount 

rates used in the LCC analysis (which are developed from a customer’s perspective). The 7-

percent real value is an estimate of the average before-tax rate of return on private capital in the 

U.S. economy. The 3-percent real value represents the “societal rate of time preference,” which 

is the rate at which society discounts future consumption flows to their present value.

14. CONSUMER SUBGROUP ANALYSIS

The LCC analysis described in section 11 analyzes the impacts of energy conservation 

standards on all consumers for computer systems. For the subgroup analysis, DOE divides 

consumers into subgroups, which comprise a subset of the population that is likely, for one 

reason or another, to be affected disproportionately by new or revised energy conservation 

standards (e.g., small businesses or firms that use computer systems in particular applications 

where energy savings are likely to differ from the mean). The purpose of a subgroup analysis is 

to determine the extent of this disproportional impact. DOE will work with interested parties to 

identify any subgroups for this consideration and will conduct a subgroup analysis for any NOPR 

developed for this rulemaking.

In comparing potential impacts on the different consumer subgroups, DOE will evaluate 

variations in regional energy prices, variations in energy use, and variations in installation costs 

that might affect the LCC savings and PBP of a standard to consumer subgroups. To the extent 

possible, DOE may obtain estimates of the variability in each input variable and consider this 

variability in its calculation of consumer impacts. It will discuss the variability in each input

variable and likely sources of information with interested parties.

Item 14-1 DOE welcomes comment on what, if any, consumer subgroups are 

appropriate in considering standards for computer systems.

15. MANUFACTURER IMPACT ANALYSIS

The MIA provides an assessment of the potential impacts of energy conservation 

standards on manufacturers of computer systems. A wide range of quantitative and qualitative 

effects may occur following the adoption of a standard that may require changes to 

manufacturing practices. DOE will identify these potential effects through interviews with 

manufacturers and other interested parties.
65

DOE will conduct an industry-wide cash-flow analysis using the Government Regulatory 

Impact Model (GRIM), identify and analyze subgroups of manufacturers whose businesses vary 

significantly from the industry as a whole, perform a competitive impacts assessment, and 

review the cumulative regulatory burden for the industry.

15.1 Sources of Information for the Manufacturer Impact Analysis

Many of the analyses described earlier provide information that DOE will use as inputs 

for the MIA. Such information includes financial parameters developed in the market assessment 

(section 5.2), cost data developed in the engineering analysis (section 8), and shipments 

projections (section 12). DOE will supplement this information with information gathered during 

manufacturer interviews, as discussed below.

During any preliminary analysis phase, DOE will conduct interviews with manufacturers 

to gain insight into the range of possible impacts resulting from potential energy conservation 

standards. These interviews will coincide with preliminary technical interviews for the 

engineering analysis.

During any NOPR phase, DOE will conduct more detailed MIA interviews with 

manufacturers. The interview process plays a key role in the MIA, because it provides an 

opportunity for directly affected parties to express their views on important issues. During the 

interviews, DOE will solicit information on the possible impacts of potential standards on 

manufacturing costs, product prices, sales, direct employment (meaning employment for the 

manufacturer only), capital assets, and industry competitiveness. Both qualitative and 

quantitative information are valuable in this analysis. DOE prefers an interactive interview 

process because it helps to clarify manufacturer input and provides the opportunity to identify 

additional issues.

DOE asks interview participants to identify confidential information and protects the 

confidentiality of the information provided as explained in section 8.3. DOE also asks 

participants to identify any information they wish to have included in the public record, but do 

not want to have associated with their interview (thereby identifying that particular 

manufacturer). DOE incorporates this information into the public record without attribution.

DOE collates the interview results and prepares a summary of the major issues and 

outcomes. This summary becomes part of the technical support document for this rulemaking.

15.2 Industry Cash Flow Analysis

The industry cash-flow analysis will rely primarily on the GRIM. DOE uses the GRIM to 

analyze the financial impacts of new energy conservation standards on the computer system

industry.

The GRIM uses a number of factors—annual expected revenues; manufacturer costs such 

as costs of goods sold; selling, general, and administrative (SG&A) costs; R&D costs; product 

conversion costs; taxes; capital expenditures (both ordinary capital expenditures and those 

related to standards); and working capital requirements—to determine annual cash flows 

associated with a new standard, beginning with the announcement of the standard and continuing 
66

for several years after its implementation. DOE compares the results against base-case 

projections that involve no new standards. The financial impact of new standards is the 

difference between the two sets of discounted annual cash flows, or the differences between the 

base-case and standards-case industry net present values. Other performance metrics, such as 

return on invested capital, are also available from the GRIM.

DOE gathers the inputs needed for the GRIM from two primary sources: (1) the analyses 

conducted to this point; and (2) interviews with manufacturers and other interested parties. As 

discussed above, information gathered from previous analyses will include financial parameters, 

manufacturing costs, price projections, and shipment projections. Interviews with manufacturers 

and other interested parties will supplement this information.

15.3 Manufacturer Subgroup Analysis

Average industry cost values may not reveal differential impacts among computer system 

manufacturer subgroups. Smaller manufacturers, niche players, and manufacturers exhibiting a 

cost structure that differs significantly from the industry average may be affected differently by 

standards. Ideally, DOE would consider the impact on every firm individually. In highly 

concentrated industries, this may be possible. In industries having numerous participants, 

however, DOE uses the results of the market and technology assessment to group manufacturers 

into subgroups, as appropriate. For computer systems, DOE is interested in feedback about 

potential subgroups, including small businesses. DOE conducts a Regulatory Flexibility Act 

analysis to determine the impacts of any standards on small businesses consistent with the 

Regulatory Flexibility Act. (5 U.S.C. 601-612)

Item 15-1 DOE seeks comments on any subgroups of computer system 

manufacturers that it should consider in a manufacturer subgroup analysis.

15.4 Competitive Impacts Assessment

EPCA directs DOE to consider any lessening of competition likely to result from the 

imposition of standards. (42 U.S.C. 6295(o)(2)(B)(i)(V)) It further directs the Attorney General 

to determine in writing the impacts, if any, of any lessening of competition likely to result from 

standards. (42 U.S.C. 6295(o)(2)(B)(ii))

DOE gathers firm-specific financial information and impacts and reports the aggregated 

impact of the proposed standard on manufacturers. The competitive impacts analysis will focus 

on assessing the impacts on smaller manufacturers. DOE bases the assessment on manufacturing 

cost data and information collected from interviews with manufacturers. The manufacturer 

interviews focus on gathering information that would help in assessing asymmetrical cost 

increases to some manufacturers, increased proportion of fixed costs potentially increasing 

business risks, and potential barriers to market entry (e.g., proprietary technologies). DOE 

provides the Attorney General with a copy of any NOPR for consideration in evaluating the 

impact of standards on the lessening of competition. DOE will publish the Attorney General’s 

letter and address any related comments in any final rule.
67

15.5 Cumulative Regulatory Burden

Other regulations (federal, state, local, or international) may apply to manufacturers of 

computer systems covered under this rulemaking as well as to other products made by these 

manufacturers. Multiple regulations may result in a significant, cumulative regulatory burden on 

these manufacturers. DOE considers the impact on these manufacturers of multiple, productspecific regulatory actions. 

Item 15-2 DOE welcomes comments on other existing regulations or pending 

regulations it should consider in examining cumulative regulatory burden.

16. EMISSIONS ANALYSIS

In the emissions analysis, conducted in the NOPR phase, DOE will estimate the reduction 

in power sector emissions of carbon dioxide (CO2), nitrogen oxides (NOx), sulfur dioxide (SO2), 

and mercury (Hg) from potential energy conservation standards for computer systems. In 

addition, DOE will estimate emissions impacts in production activities (extracting, processing, 

and transporting fuels) that provide the energy inputs to power plants. These are referred to as 

“upstream” emissions. Together, these emissions account for the FFC discussed in section 14.2. 

In accordance with DOE’s FFC Statement of Policy (76 FR 51281;Aug. 18, 2011), the FFC 

analysis also includes impacts on emissions of methane (CH4) and nitrous oxide (NOX), both of 

which are recognized as greenhouse gases. 

DOE primarily conducts the emissions analysis using emissions factors for CO2 and most 

of the other gases derived from data in EIA’s most recent AEO. Combustion emissions of CH4

and N2O are estimated using emissions intensity factors published by the Environmental 

Protection Agency (EPA), GHG Emissions Factors Hub.48

EIA prepares the AEO using NEMS. Each annual version of NEMS incorporates the 

projected impacts of existing air quality regulations on emissions. The text below refers to AEO 

2013, which generally represents current legislation and environmental regulations, including 

recent government actions, for which implementing regulations were available as of December 

31, 2012.

SO2 emissions from affected electric generating units (EGUs) are subject to nationwide 

and regional emissions cap-and-trade programs. Title IV of the Clean Air Act sets an annual 

emissions cap on SO2 for affected EGUs in the 48 contiguous States and the District of Columbia 

(D.C.). SO2 emissions from 28 eastern States and D.C. were also limited under the Clean Air 

Interstate Rule (CAIR), which created an allowance-based trading program that operates along 

with the Title IV program in those States and D.C. 70 FR 25162 (May 12, 2005). CAIR was 

remanded to the U.S. Environmental Protection Agency (EPA) by the U.S. Court of Appeals for 

 

48 http://www.epa.gov/climateleadership/guidance/ghg-emissions.html
68

the District of Columbia Circuit (D.C. Circuit), but it remained in effect.49 On July 6, 2011, EPA 

issued a replacement for CAIR, the Cross-State Air Pollution Rule (CSAPR). 76 FR 48208 

(August 8, 2011). On August 21, 2012, the D.C. Circuit issued a decision to vacate CSAPR.50

The court ordered EPA to continue administering CAIR. AEO 2013 assumes that CAIR remains 

a binding regulation through 2040.51

The attainment of emissions caps is typically flexible among EGUs and is enforced 

through the use of emissions allowances and tradable permits. Under existing EPA regulations, 

any excess SO2 emissions allowances resulting from the lower electricity demand caused by the 

adoption of an energy conservation standard could be used to permit offsetting increases in SO2

emissions by any regulated EGU. In past rulemaking efforts, DOE recognized that there was 

uncertainty about the effects of conservation standards on SO2 emissions covered by the existing 

cap-and-trade system, but it concluded that no reductions in power sector SO2 emissions would 

occur for SO2 as a result of standards.

Beginning in 2016, however, SO2 emissions will fall as a result of the Mercury and Air 

Toxics Standards (MATS) for power plants, which were announced by EPA on December 21, 

2011. 77 FR 9304 (February 16, 2012). In the final MATS rule, EPA established a standard for 

hydrogen chloride as a surrogate for acid gas hazardous air pollutants (HAP), and also 

established a standard for SO2 (a non-HAP acid gas) as an alternative equivalent surrogate 

standard for acid gas HAP. The same controls are used to reduce HAP and non-HAP acid gas; 

thus, SO2 emissions will be reduced as a result of the control technologies installed on coal-fired 

power plants to comply with the MATS requirements for acid gas. AEO 2013 assumes that, in 

order to continue operating, coal plants must have either flue gas desulfurization or dry sorbent 

injection systems installed by 2016. Both technologies, which are used to reduce acid gas 

emissions, also reduce SO2 emissions. Under the MATS, emissions will be far below the cap that 

would be established by CAIR, so it is unlikely that excess SO2 emissions allowances resulting 

from the lower electricity demand would be needed or used to permit offsetting increases in SO2

emissions by any regulated EGU. Therefore, DOE believes that energy efficiency standards will 

reduce SO2 emissions in 2016 and beyond.

CAIR established a cap on NOx emissions in the 28 eastern states and the District of 

Colombia. Energy conservation standards are expected to have little or no physical effect on 

 

49 See North Carolina v. EPA, 550 F.3d 1176 (D.C. Cir. 2008); North Carolina v. EPA, 531 F.3d 896 (D.C. Cir. 

2008).

50 See EME Homer City Generation, LP v. EPA, 696 F.3d 7, 38 (D.C. Cir. 2012).

51 On April 29, 2014, the U.S. Supreme Court reversed the judgment of the D.C. Circuit. The case will now return to 

the D.C. Circuit for further proceedings consistent with the Supreme Court's opinion. The Supreme Court held in 

part that EPA's methodology for quantifying emissions that must be eliminated in certain states due to their impacts 

in other downwind states was based on a permissible, workable, and equitable interpretation of the Clean Air Act 

provision that provides statutory authority for CSAPR. See EPA v. EME Homer City Generation, Slip. Op. No 12-

1182, *32 slip op. at 32 (U.S. April 29, 2014). Because DOE would be using emissions factors based on AEO 2013 

for the NOPR phase of this rulemaking, this document assumes that CAIR, not CSAPR, is the regulation in force.

The difference between CAIR and CSAPR is not relevant for the purpose of DOE's analysis of SO2 emissions.
69

these emissions in those states covered by CAIR because excess NOx emissions allowances 

resulting from the lower electricity demand could be used to permit offsetting increases in NOx

emissions. However, standards would be expected to reduce NOx emissions in the states not 

affected by CSAPR the caps, so DOE estimates NOx emissions reductions from potential 

standards in the States where emissions are not capped for these states.

The MATS limit mercury emissions from power plants, but they do not include emissions 

caps and, as such, DOE’s energy conservation standards would likely reduce Hg emissions. DOE 

will estimate mercury emissions reduction using emissions factors based on AEO 2013, which 

incorporates the MATS. 

Power plants may emit particulates from the smoke stack, which are known as direct 

particulate matter (PM) emissions. NEMS does not account for direct PM emissions from power 

plants. DOE is investigating the possibility of using other methods to estimate reduction in PM 

emissions due to standards. The great majority of ambient PM associated with power plants is in 

the form of secondary sulfates and nitrates, which are produced at a significant distance from 

power plants by complex atmospheric chemical reactions that often involve the gaseous 

emissions of power plants, mainly SO2 and NOx. The monetary benefits that DOE estimates for 

reductions in SO2 and NOx emissions resulting from standards are in fact primarily related to the 

health benefits of reduced ambient PM.

Item 16-1 DOE seeks comments on its approach to conduct the emissions analysis 

for the products that would be covered by any proposed rulemaking that 

would regulate computer system efficiency.

17. MONETIZING REDUCED CARBON DIOXIDE AND OTHER EMISSIONS

DOE plans to consider the estimated monetary benefits likely to result from the reduced 

emissions of CO2 and NOx that are expected to result from each of the standard levels 

considered.

To estimate the monetary value of benefits resulting from reduced emissions of CO2, 

DOE plans to use the most current Social Cost of Carbon (SCC) values developed and/or agreed 

to by an interagency process. The SCC is intended to be a monetary measure of the incremental 

damage resulting from greenhouse gas (GHG) emissions, including, but not limited to, net 

agricultural productivity loss, human health effects, property damage from sea level rise, and 

changes in ecosystem services. Any effort to quantify and to monetize the harms associated with 

climate change will raise serious questions of science, economics, and ethics. But with full 

regard for the limits of both quantification and monetization, the SCC can be used to provide 

estimates of the social benefits of reductions in GHG emissions. 
70

The Interagency Working Group on Social Cost of Carbon released in 2013 an update of 

its previous report in 2013.52 The most recent estimates of the SCC in 2015, expressed in 2013$, 

are $12.0, $40.5, $62.4, and $119 per metric ton of CO2 avoided. For emissions reductions that 

occur in later years, these values grow in real terms over time. Additionally, the interagency 

group determined that a range of values from 7-percent to 23-percent should be used to adjust the 

global SCC to calculate domestic effects, although DOE will give preference to consideration of 

the global benefits of reducing CO2 emissions. 

DOE multiplies the CO2 emissions reduction estimated for each year by the SCC value 

for that year in each of the four cases. To calculate a present value of the stream of monetary 

values, DOE discounts the values in each of the four cases using the discount rates that had been 

used to obtain the SCC values in each case.

DOE recognizes that scientific and economic knowledge continues to evolve rapidly as to 

the contribution of CO2 and other GHG to changes in the future global climate and the potential 

resulting damages to the world economy. Thus, these values are subject to change. 

DOE also estimates the potential monetary benefit of reduced NOx emissions resulting 

from the standard levels it considers. For NOx emissions, estimates suggest a very wide range of 

monetary values, ranging from $476 to $4,893 per ton in 2013$.53 DOE calculates monetary 

benefits using a medium value for NOX emissions of $2,684 per short ton (2013$), and real 

discount rates of 3 percent and 7 percent.

DOE is evaluating the appropriate valuation of avoided SO2 and Hg emissions. Whether 

monetization of reduced SO2 and Hg emissions will occur as part of any proposed rule that DOE 

issues for computer systems is yet to be determined.

Item 17-1 DOE requests comments on the approach it plans to use for estimating 

monetary benefits associated with emissions reductions.

18. UTLITY IMPACT ANALYSIS

To estimate the effects of energy conservation standards for computer systems on the 

electric utility industry, DOE plans to use a variant of EIA’s NEMS, called NEMS-BT. NEMS is 

a large, multi-sectoral partial equilibrium model of the U.S. energy sector, used primarily for the 

 

52 Technical Update of the Social Cost of Carbon for Regulatory Impact Analysis Under Executive Order 12866. 

Interagency Working Group on Social Cost of Carbon, U. S. Government, revised November 2013. 

http://www.whitehouse.gov/sites/default/files/omb/assets/inforeg/technical-update-social-cost-of-carbon-forregulator-impact-analysis.pdf

53 U.S. Office of Management and Budget, Office of Information and Regulatory Affairs, 2006 Report to Congress 

on the Costs and Benefits of Federal Regulations and Unfunded Mandates on State, Local, and Tribal Entities, 

Washington, DC.
71

purpose of preparing EIA’s AEO. NEMS produces a widely recognized reference case forecast 

for the United States through 2040 and is available in the public domain. 

The effect of reducing site energy use is modeled by making NEMS runs that deviate 

from the most recent AEO Reference case. Each year, DOE develops response coefficients using 

the NEMS-BT which give changes in capacity and generation by fuel type for a given quantity of 

site energy use reduction to a particular energy end use. DOE develops response coefficients for 

several different energy end uses. To model the impact of this standard on the electric utility 

industry, the response coefficients will be weighted by end use, and then they will be applied to 

the site energy savings for computer systems which is generated from the NIA analysis.

Item 18-1 DOE seeks input from stakeholders on its proposed use of NEMS-BT to 

conduct the utility impact analysis.

19. EMPLOYMENT IMPACT ANALYSIS

The employment impact analysis examines indirect employment impacts from standards, 

which consist of the net jobs created or eliminated in the national economy, other than in the 

manufacturing sector being regulated, caused by: (1) reduced spending by end users on energy; 

(2) reduced spending on new energy supply by the utility industry; (3) increased spending on 

new equipment to which the new standards apply; and (4) the effects of those three factors 

throughout the economy. (Direct employment impacts are any changes in the number of 

employees of manufacturers of the equipment subject to standards, their suppliers, and related 

service firms. The MIA will address impacts on the number of employees working for the 

manufacturers).

One method for assessing the possible effects on the demand for labor of such shifts in 

economic activity is to compare sector employment statistics developed by the Labor 

Department’s Bureau of Labor Statistics (BLS). The BLS regularly publishes its estimates of the 

number of jobs per million dollars of economic activity in different sectors of the economy, as 

well as the jobs created elsewhere in the economy by this same economic activity. Data from 

BLS indicate that expenditures in the utility sector generally create fewer jobs (both directly and 

indirectly) than expenditures in other sectors of the economy.54 There are many reasons for these 

differences, including wage differences and the fact that the utility sector is more capitalintensive and less labor-intensive than other sectors. Energy conservation standards have the 

effect of reducing consumer utility bills. Because reduced consumer expenditures for energy 

likely lead to increased expenditures in other sectors of the economy, the general effect of 

efficiency standards is to shift economic activity from a less labor-intensive sector (i.e., the 

utility sector) to more labor-intensive sectors (e.g., the retail and service sectors). 

 

54 See Bureau of Economic Analysis, Regional Multipliers: A User Handbook for the Regional Input-Output 

Modeling System (RIMS II). Washington, DC. U.S. Department of Commerce, 1992.
72

Once DOE issues a NOPR, DOE plans to estimate indirect national employment impacts 

using an input/output model of the U.S. economy called Impact of Sector Energy Technologies 

version 3.1.1 (ImSET).55 ImSET is a special-purpose version of the “U.S. Benchmark National 

Input-Output” (I–O) model, which was designed to estimate the national employment and 

income effects of energy-saving technologies. The ImSET software includes a computer-based 

I–O model having structural coefficients that characterize economic flows among 187 sectors 

most relevant to industrial, commercial, and residential building energy use. 

DOE notes that ImSET is not a general equilibrium forecasting model and understands 

the uncertainties involved in projecting employment impacts, especially changes in the later 

years of the analysis. Because ImSET does not incorporate price changes, the employment 

effects predicted by ImSET may over-estimate actual job impacts over the long run. DOE may 

consider the use of other modeling approaches for examining long-run employment impacts.

Item 19-1 DOE seeks feedback on its proposed approach to assessing national 

employment impacts.

20. REGULATORY IMPACT ANALYSIS

If DOE issues a proposal to set standards for computer systems, it will prepare a 

regulatory impact analysis to address the potential for non-regulatory approaches to supplant or 

augment energy conservation standards to improve the efficiency of computer systems. DOE 

recognizes that voluntary or other non-regulatory efforts by manufacturers, utilities, and other 

interested parties can result in substantial improvements in efficiency. DOE intends to analyze 

the likely effects of non-regulatory initiatives on equipment energy use, customer utility, and 

LCC. DOE will attempt to base its assessment on the impacts of any such initiatives to date, but 

will also consider information presented regarding the impacts that an initiative might have in the 

future.

 

55 J. M. Roop, M. J. Scott, and R. W. Schultz, ImSET 3.1: Impact of Sector Energy Technologies, PNNL-18412,

Pacific Northwest National Laboratory, 2009. <www.pnl.gov/main/publications/external/technical_reports/PNNL18412.pdf>
73

APPENDIX A. SCOPE OF INDUSTRY STANDARDS

A.1 Scope of Existing Computer Standards

DOE evaluated several industry, regulatory, and voluntary standards for computers in 

consideration for the scope of this rulemaking. The following sections discuss the scope of the 

computer industry standards.

A.1.1 ENERGY STAR Program Scope for Computers

ENERGY STAR Computers V. 5.2 and V. 6.0 require that all products covered under the 

scope of coverage must meet the definition of a computer as well as one of the included 

product’s definitions such as a desktop or notebook computer. ENERGY STAR also includes a 

list of products that are excluded from this program. A list of included and excluded products for 

ENERGY STAR Computers V. 5.2 is specified in Table A-1. 

Table A-1: ENERGY STAR Computers V. 5.2 Scope of Coverage

Included Products Excluded Products

Desktop computers

Integrated desktop computers

Notebook computers

Workstations

Small-scale servers

Thin clients

Computer servers

Handheld computers

Game consoles

Personal Digital Assistant devices (PDAs)

Smartphones

Handheld gaming devices

ENERGY STAR Computers V. 6.0 adds definitions for mobile thin clients and ultra-thin 

clients to distinguish them from notebook computers and thin clients respectively. Additionally, 

point of sale (POS) systems, tablet computers, and ultra-thin clients were added to the list of 

excluded products under the scope of coverage. These changes are specified in Table A-2. 

Table A-2: Scope Updates in ENERGY STAR Computers V. 6.0 from V. 5.2

Included Products Excluded Products

Mobile thin clients Point of sale systems

Tablet computers

Ultra-thin clients

A.1.2 Scope of Industry and Regulatory Programs for Computers

While EU No. 617/2013 and AS/NZS 5813:2012 closely align with ENERGY STAR 

Computers V. 5.2’s testing requirements, there are some differences in scope between these 

programs. Table A-3 highlights only the differences between ENERGY STAR Computers V. 

6.0, AS/NZS 5813:2012, and EU No. 617/2013, and omits consistencies with ENERGY STAR 

Computers V. 6.0. Additionally, IEC 62623 Ed. 1.0 and ECMA-383 Ed. 3 are not included in 

this comparison because they only cover desktop, integrated desktop, and notebook computers in 

their scope of coverage.
74

Table A-3: Differences in Scope of Coverage for Regulatory Programs

Included Excluded

ENERGY STAR Computers V. 

6.0

Thin clients

Workstations Tablet computers

AS/NZS 5813:2012 Thin clients

Workstations

EU No. 617/2013 Tablet computers

Docking stations

Thin clients*

Workstations*

Small-scale servers*

* EU does not measure the power consumption of these products. They are technically in scope but only to measure 

the internal power supply efficiency.

A.2 Scope of Existing Computer Server Standards

DOE evaluated several regulatory and voluntary standards for computers in consideration 

for the scope of this rulemaking. The following sections discuss the scope of the computer server 

industry standards.

A.2.1 ENERGY STAR Program Scope for Computer Servers

ENERGY STAR Computer Servers V. 2.0 includes blade, multi-node, rack mounted, and 

pedestal servers with four or fewer physical CPUs in its scope. The products included and 

excluded from the ENERGY STAR Computer Servers V. 2.0 scope as specified in Table A-4. 

Table A-4: ENERYGY STAR Computer Servers V. 2.0 Scope of Coverage

Included Products Excluded Products

Rack servers

Multi-node servers

Pedestal servers

Microservers/cloud servers

Blade systems

Fully fault tolerant servers

Server appliances

High performance computing systems

Large servers

Storage products including blade storage

Network equipment

A.2.2 Scope of Regulatory Programs for Computer Servers

Of the other regulatory programs that DOE evaluated, EU’s EC Regulation No. 617/2013 

(Lot 3) also targets rack and pedestal servers with four or fewer physical CPUs but, these 

regulations do not include a test procedure. Instead, requirements are provided for the minimum 

power supply efficiency and power factor. 

The Japanese Ministry of Economy, Trade and Industry’s Top Runner Program for 

Computers & Hard Disks targets computer servers, defined as “a computer that is designed to 

operate 24 hours a day and provide services on a network, and which can be accessed only via 

the network”, but excludes very high and very low performance systems. The test procedure in 

the program includes an idle state power measurement test, which is then compared to the 

maximum theoretical performance to obtain an efficiency figure. This program uses different 

compliance standards for each product class, which are determined based on a product’s 

hardware characteristics.
75

The Korean Ministry of Trade, Industry and Energy works with the Korea Energy 

Management Corporation (KEMCO) to develop the E-Standby Program. This targets computer 

servers with two or fewer physical CPUs and a power supply rating of less than 3,000 watts, but 

excludes blade and multi-node servers. A test procedure is defined for measuring the standby 

power of covered products, there is a different compliance standard for each product class, which 

is determined based on a product’s hardware characteristics.
76

APPENDIX B. LIST OF ITEMS FOR COMMENT

Item 3-1 DOE requests comment on the definition of a computer or alternate approaches that 

should be considered. Specifically, DOE requests suggestions of characteristics that may be used 

in the definition to distinguish general consumer electronics from computers. ........................... 15

Item 3-2 DOE requests feedback and information on additional factors and criteria that could 

be used to distinguish clearly between computer servers and client computers, other than those 

based on point-of-sale or end-use. ................................................................................................ 16

Item 3-3 DOE requests comment on using ENERGY STAR Computers V. 6.0 and ENERGY 

STAR Computers Final Draft V. 6.1 as the basis for computer product definitions. DOE also 

requests comment on any additional computer product definitions that should be included. ...... 18

Item 3-4 DOE requests comment on the need for a tablet computer definition. DOE also 

requests comment on the criteria used to distinguish tablet computers from other computers as 

well as any suggestions for the definition..................................................................................... 18

Item 3-5 DOE requests comment on the types of computers that should be excluded from the 

scope. .................................................................................................................................... 19

Item 3-6 DOE requests comment on using computer product characteristics to narrow the 

scope of coverage or more accurately define products. In particular, what design characteristics 

would best be used to separate out tablets? .................................................................................. 19

Item 3-7 Based on DOE’s definition of a consumer product, DOE requests comment on 

additional methods (besides ability to operate on a residential circuit) to identify computer 

servers that are consumer products. Are there alternative strategies that can be used to create a 

scope of coverage which distinguishes consumer computer servers from those that are 

exclusively used in commercial/data-center environments?......................................................... 21

Item 3-8 DOE requests feedback on the proposed scope for UPSs. In particular, whether or not 

industry believes a particular UPS type should be included within the scope.............................. 22

Item 3-9 DOE requests feedback on using UPS product characteristics to narrow the scope of 

coverage. DOE further requests feedback on whether capacity is a proper differentiator between 

consumer and commercial UPSs and what constitutes a proper cut-off capacity. ....................... 23

Item 4-1 DOE requests comment on the use of IEC 62623 Ed. 1.0 as the basis for the 

development of the computers test method. ................................................................................. 24

Item 4-2 DOE requests comment on providing additional guidance as provided in ENERGY 

STAR Computers V. 6.0. Specifically, DOE requests comment on the luminance values 

specified in ENERGY STAR Computers V. 6.0 for integrated desktops and notebooks. Are these 

values sufficient or does the luminance need to be higher for integrated displays?..................... 25

Item 4-3 DOE requests comment on the inclusion of ENERGY STAR Computers V. 6.0 mode 

weightings..................................................................................................................................... 26

Item 4-4 DOE requests comment on adopting the ENERGY STAR Computers V. 6.0 

weightings for AEC based on network proxy functionality. Specifically, DOE requests comment 

on the weighting values assigned to each proxy level. ................................................................. 27

Item 4-5 DOE requests comment on a standardized and objective method to identify the level 

of proxy functionality on computers. Specifically, DOE welcomes information on steps that can 

objectively determine the proxy level on different OSs. .............................................................. 27

Item 4-6 DOE requests comment on the best approach to address network proxying: (a) using 

four levels of weightings for proxy functionality as specified in ENERGY STAR Computers V. 

6.0 in addition to the conventional weightings; (b) using two levels of weightings, one for no 
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network proxy functionality and the other for network proxy functionality; and, (c) using a single 

weighting for all computers. ......................................................................................................... 27

Item 4-7 For each of the approaches, DOE requests comment on the network proxy weighting 

that is representative of the computer’s AEC and is identifiable on all OSs................................ 27

Item 4-8 DOE requests comment on the use of the idle state test from the ENERGY STAR 

Computer Servers V. 2.0 Test Method for computer servers as a base for the development of the 

computer servers test method........................................................................................................ 30

Item 4-9 DOE requests feedback on its adoption of the IEC 62040-3 Ed.2.0 standard as a basis 

for the development of the UPS test method, while considering additional guidance provided in 

ENERGY STAR UPS V. 1.0........................................................................................................ 31

Item 5-1 DOE requests comment on the proposed approach for determining computer systems 

product classes. DOE welcomes comments on any design characteristics that should be 

considered when establishing product classes. ............................................................................. 32

Item 5-2 DOE requests comment on the categorization criteria for the ENERGY STAR 

Computers V. 5.2 product categories............................................................................................ 35

Item 5-3 DOE requests comment on the memory, graphics, and storage sub- categorization and 

energy allowances from ENERGY STAR Computers V. 5.2. ..................................................... 35

Item 5-4 DOE requests comment on whether the CPU performance metric effectively 

classifies the performance of a CPU............................................................................................. 37

Item 5-5 DOE requests comment on the granularity of seven graphics categories consistent 

with the market of available GPUs. .............................................................................................. 37

Item 5-6 DOE requests comment on the enhanced performance display and integrated display 

performance features..................................................................................................................... 37

Item 5-7 DOE requests comment on the absence of product categories for thin clients and 

small-scale servers. ....................................................................................................................... 37

Item 5-8 DOE requests comment on possible strategies for computer server product classes. 

DOE requests comment on possible advantages and shortcomings of using the ENERGY STAR 

Computer Servers V. 2.0 classification criteria for the purpose of this rulemaking..................... 38

Item 5-9 DOE requests comment on possible advantages and shortcomings of using the 

ENERGY STAR UPS V. 1.0 product classification criteria for the purpose of this rulemaking. 40

Item 6-1 DOE requests information that would contribute to the market assessment for 

computers, computer servers, and UPSs that would be covered in this rulemaking. DOE 

particularly seeks information on shipments, trends in product feature and efficiency, distribution 

channels and estimates of market shares for the computers, computer servers, and UPSs 

considered in this rulemaking. ...................................................................................................... 41

Item 6-2 DOE requests comment and/or information on the current technological status of 

error-resilient circuitry. ................................................................................................................. 46

Item 6-3 DOE welcomes comments on the preliminary technology options for computer 

systems identified in this section and whether there are other technology options it should 

consider. In commenting on technology options, please discuss their impacts, if any, on safety, 

performance, and user utility, as well as cost of the technology options...................................... 49

Item 7-1 Are there any technologies, including those listed in sections 6.2, 6.3, and 6.4 that 

DOE should not consider because of any of the four screening criteria? If so, which screening 

criteria apply to the cited technology or technologies? ................................................................ 50

Item 8-1 DOE encourages interested parties to submit data that will improve DOE’s 

understanding of computer systems’ performance and associated costs. ..................................... 51
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Item 9-1 DOE seeks suggestions and comments concerning its proposed approach to 

developing estimates of markups.................................................................................................. 55

Item 10-1 DOE seeks comments on its proposed approach for specifying typical annual 

energy consumption. Most importantly, DOE is interested in sources of data that can assist in 

characterizing the annual energy consumption of computer systems........................................... 56

Item 10-2 DOE welcomes input on data sources that it can use to characterize the variability 

in annual energy consumption for computer systems in the field. DOE is particularly interested 

in field monitoring studies and data.............................................................................................. 56

Item 11-1 DOE seeks comments on its proposed approach of using probability distributions 

and Monte Carlo simulation to conduct the LCC and PBP analysis. ........................................... 58

Item 11-2 DOE requests data from stakeholders to characterize the current mix of computer 

system efficiencies in the market.................................................................................................. 58

Item 11-3 DOE seeks comments on the planned approach for estimating current and 

forecasted energy prices................................................................................................................ 59

Item 11-4 DOE seeks comments on the merits of its proposed analytical assumption that 

changes in maintenance, repair, and installation costs will be negligible for more-efficient 

computer systems. If that assumption is incorrect, DOE is interested in the reasons why this is so 

and in specific ways to correct that assumption............................................................................ 59

Item 11-5 DOE seeks comments on appropriate product lifetimes for computer systems. 

Specifically, DOE seeks data sources for establishing product lifetimes..................................... 59

Item 11-6 DOE seeks comments on its planned approach for estimating discount rates for 

residential and commercial consumers. ........................................................................................ 60

Item 11-7 DOE seeks comments on computer system efficiency in the base case, historical 

efficiency data on computer systems, and projected trends in computer system efficiency. ....... 60

Item 12-1 DOE seeks historical shipments data and reports on future market trends from 

stakeholders. If such data are provided, DOE requests market share data showing the percentage 

of computer system shipments of different efficiencies and product classes. .............................. 61

Item 12-2 As part of the preliminary manufacturer impact analysis, DOE seeks input from 

manufacturers on the potential impact of new energy conservation standards on computer system 

shipments. DOE also seeks input from other stakeholders on the potential impact of standards on 

product shipments. ........................................................................................................................ 62

Item 12-3 DOE also requests input on any current market-pull programs that promote the 

adoption of more efficient computer systems............................................................................... 62

Item 13-1 DOE seeks comments on the use of the “roll-up” and “shift” efficiency scenarios to 

characterize the impact that potential standards would have on the product efficiency 

distributions. ................................................................................................................................. 63

Item 14-1 DOE welcomes comment on what, if any, consumer subgroups are appropriate in 

considering standards for computer systems. ............................................................................... 64

Item 15-1 DOE seeks comments on any subgroups of computer system manufacturers that it 

should consider in a manufacturer subgroup analysis. ................................................................. 66

Item 15-2 DOE welcomes comments on other existing regulations or pending regulations it 

should consider in examining cumulative regulatory burden. ...................................................... 67

Item 16-1 DOE seeks comments on its approach to conduct the emissions analysis for the 

products that would be covered by any proposed rulemaking that would regulate computer 

system efficiency. ......................................................................................................................... 69
79

Item 17-1 DOE requests comments on the approach it plans to use for estimating monetary 

benefits associated with emissions reductions.............................................................................. 70

Item 18-1 DOE seeks input from stakeholders on its proposed use of NEMS-BT to conduct 

the utility impact analysis. ............................................................................................................ 71

Item 19-1 DOE seeks feedback on its proposed approach to assessing national employment 

impacts. ................................................................................................................................. 72