1 | Building Technologies Program eere.energy.gov

The Parker Ranch installation in Hawaii

BUILDING TECHNOLOGIES PROGRAM

Distribution Transformers

Energy Conservation Program

Notice of Proposed Rulemaking (NOPR) Analysis

James Raba

U.S. Department of Energy

Energy Efficiency & Renewable Energy

Jim.Raba@ee.doe.gov

February 23, 2012
2 | Building Technologies Program eere.energy.gov

• Introductions

• Role of the Facilitator

• Ground Rules (norms)

– Listen as an ally

– Use short, succinct statements/keep to the point

– Hold sidebar conversations outside the room

– Focus on issues, not personalities

– One person speak at a time (raise hand to be recognized; state your 

name for the record)

– Set cell phones to silent/vibrate

• Housekeeping Items

• Agenda Review

• Opening Remarks

Welcome and Introduction
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• Invite comment on proposed energy conservation levels.

• Present methodologies and characterize results of the rulemaking 

analyses.

• Provide a forum for public discussion of rulemaking issues.

• Encourage interested parties to submit data, information, and written 

comments.

• Describe next steps in the rulemaking.

Purpose of the Public Meeting
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• Participants are invited to provide summary comments or 

statements and raise additional issues for discussion.

• NOPR comment period closes April 10, 2012.

Comments from Participants
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Issues for Comment

Issue Box The Department welcomes comments, data, 

and information concerning its NOPR for distribution 

transformers. Throughout this presentation, specific issues 

will be raised for discussion on slides such as this, with 

identifying numbers corresponding to issues for comment 

from section VII.E of the NOPR. Whether invited by an 

issue box or not, comments concerning any part of the 

document or presentation are welcome.

Issue box numbering corresponds to the list of issues published at the 

end of the NOPR, available at:

http://www1.eere.energy.gov/buildings/appliance_standards/pdfs/distrib

ution_transformers_nopr_notice.pdf
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• In all correspondence, please refer to the Distribution Transformers 

rulemaking by:

– Distribution Transformers Rulemaking,

– Docket Number EE–2010–BT–STD–0048, and

– Regulatory Identification Number (RIN) 1904–AC04 

• Email: DistributionTransformers-2010-STD-0048@ee.doe.gov 

• Comment period closes: April 10, 2012

Feedback Is Requested

Postal: Hand Delivery/Courier:

Ms. Brenda Edwards

U.S. Department of Energy

Building Technologies Program, Mailstop EE-2J

1000 Independence Avenue, SW

Washington, DC 20585-0121

Ms. Brenda Edwards

U.S. Department of Energy

Building Technologies Program, Suite 600

950 L’Enfant Plaza, SW

Washington, DC 20024

Tel: 202-586-2945
7 | Building Technologies Program eere.energy.gov

Regulatory History

• EPACT 2005 set standards for low-voltage dry-type (LVDT) distribution 

transformers at the NEMA TP 1-2002 level.

• October 2007 – DOE issued a final rule establishing standards for liquid-immersed 

and medium-voltage dry-type (MVDT) distribution transformers. (72 FR 58190). 

DOE was sued on that rule concerning issues of environmental compliance. That 

suit was settled.

• As a result of the settlement agreement, compliance was required in 2010 with the 

standards established in 2007 final rule. However, DOE agreed to an expedited 

timeline to determine whether to amend standards for liquid-immersed and MVDT 

distribution transformers.

• DOE issued a Notice of Proposed Rulemaking on February 1, 2012.

• Final Rule must be published by October 1, 2012.
8 | Building Technologies Program eere.energy.gov

Distribution Transformers 

Rulemaking Schedule

2011 2012 2013 2014 2015 2016

Milestone Date

Issuance of NOPR February 1, 2012

Federal Register Notice of Public Meeting and Availability 

of the NOPR Technical Support Document February 10, 2012

Issue Final Rule October 1, 2012

Compliance Date January 1, 2016
9 | Building Technologies Program eere.energy.gov

• DOE established two subcommittees under the Energy 

Efficiency and Renewable Energy Advisory Committee 

(ERAC) to negotiate proposed Federal standards for 

distribution transformers.

– One for liquid-immersed and MVDT (established in July 2011) 

and one for LVDT (established in August 2011)

– Both included manufacturers of transformers and steel, utilities, 

energy advocacy groups, trade associations, and others.

– Each committee met 4 times in-person and had 2 webinars 

between September and December 2011.

• Stakeholders and DOE felt that a negotiated rulemaking 

would result in a better-informed analysis and reduce potential 

negative impacts of the NOPR.

Negotiated Rulemaking 

Subcommittees
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• The liquid-immersed and MVDT committee reached consensus 

regarding proposed standards for MVDT distribution transformers 

only.

The consensus addressed one design line and authorized 

DOE to undertake certain technical calculations to scale the 

agreement to other MVDT design lines

• The LVDT committee was unable to reach consensus regarding 

proposed standards for LVDT distribution transformers.

Negotiated Rulemaking Results
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EPCA Factors

42 U.S.C. 6295(o)(2)(B)(i) directs DOE to consider seven factors when 

setting energy conservation standards for distribution transformers:

EPCA Factors DOE Analysis

1. Economic impact on consumers and 

manufacturers

Life-Cycle Cost Analysis

Manufacturer Impact Analysis

2. Lifetime operating cost savings compared 

to increased cost for the product

Life-Cycle Cost Analysis

3. Total projected energy savings National Impact Analysis 

4. Impact on utility or performance Engineering Analysis

Screening Analysis

5. Impact of any lessening of competition Manufacturer Impact Analysis

6. Need for national energy conservation National Impact Analysis

7. Other factors the Secretary considers 

relevant

Environmental Assessment

Utility Impact Analysis

Employment Impact Analysis
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Steps in the Standards Rulemaking: 

NOPR

Framework

Document

Preliminary

Analysis NOPR Final

Rule

Manufacturer

 Impact 

 Analysis

Utility

 Impact 

Analysis

Employment

 Impact

 Analysis

Life-Cycle 

Cost 

Subgroup 

Analysis

Environmental 

Assessment

Regulatory

 Impact 

Analysis

Life-Cycle

Cost &

Payback 

Period

Analyses

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date

Shipments 

& National 

Impact

Analysis

Screening, 

Market and 

Technology

Analyses

Markups & 

Energy Use

Analysis
13 | Building Technologies Program eere.energy.gov

Analyses for Final Rule

Framework

Document NOPR Final 

 Rule

Revise NOPR 

Analyses

Preliminary 

Analysis
14 | Building Technologies Program eere.energy.gov

Rulemaking Scope and Current Efficiency 

Standards for Distribution Transformers

Distribution 

Transformers

LiquidImmersed Dry-Type

Low-Voltage 

Dry-Type

Medium-Voltage 

Dry-Type

BIL 20-45 BIL 46-95 BIL ≥96 

(2007 Final Rule)

NEMA TP 1-2002

(EPACT 2005)

(2007 Final Rule)
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Distribution Transformers Definitions

• EPACT 2005 presented the definition of a distribution transformer, and 

DOE refined the definition during the 2006 test procedure rulemaking. 

(71 FR 24972)

• Under 10 CFR 431.192, the term 'distribution transformer' means a 

transformer that:

– Has an input voltage of 34.5 kilovolts or less

– Has an output voltage of 600 volts or less; 

– Is rated for operation at a frequency of 60 Hertz; and

– Has a capacity of 10 kVA to 2500 kVA for liquid-immersed units and 15 kVA 

to 2500 kVA for dry-type units; but

– Is not an: autotransformer, drive (isolation) transformer, grounding 

transformer, machine-tool (control) transformer, nonventilated transformer, 

rectifier transformer, regulating transformer, sealed transformer, specialimpedance transformer, testing transformer, transformer with tap range of 

20 percent or more, uninterruptible power supply transformer, or welding 

transformer.
16 | Building Technologies Program eere.energy.gov

Distribution Transformers Definitions 

(Continued)

• ‘Liquid-immersed distribution transformer’ means a distribution 

transformer in which the core and coil assembly is immersed in an 

insulating liquid. (10 CFR 431.192)

• ‘Low-voltage dry-type (LVDT) distribution transformer’ means a 

distribution transformer that :

– has an input voltage of 600 volts or less; 

– is air-cooled; and

– does not use oil as a coolant. (42 U.S.C. 6291(38))

• ‘Medium-voltage dry-type (MVDT) distribution transformer’ means a 

distribution transformer in which the core and coil assembly is immersed 

in a gaseous or dry compound insulating medium, and which has a 

rated primary voltage between 601 V and 35 kV. (10 CFR 431.192)
17 | Building Technologies Program eere.energy.gov

Definitions:

Request for Comment

Issue 5: DOE requests comment on its proposal to require 

rectifier and testing transformers to indicate on their 

nameplates that they are for such purposes exclusively.

Issue 6: DOE requests comment on its proposal to maintain 

the definition of mining transformer but also requests 

information useful in precisely expanding the definition to 

encompass any activity that entails the removal of material 

underground, such as digging or tunneling.

• “Underground mining transformer” means an MVDT transformer that:

• Is built only for installation in an underground mine or inside equipment for 

use in an underground mine, and

• Has a nameplate which identifies the transformer as being for this use only. 

(10 CFR 431.192)
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Test Procedure Overview

• DOE published a test procedure (TP) final rule for distribution 

transformers on April 27, 2006. (71 FR 24972)

– Based on NEMA TP-2 test procedure.

– Same TP for all three transformer types

• The test procedure is codified in 10 CFR Part 431, Appendix A to 

Subpart K, “Uniform Test Method for Measuring the Energy 

Consumption of Distribution Transformers.”
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Test Procedure Issues

• Multiple Voltage Secondaries: DOE currently requires testing at the 

voltage with the highest losses, which is usually in the parallel 

configuration, but it is considering allowing manufacturers to meet 

amended standards in any secondary configuration and at the lowest BIL.

Issue 1: DOE seeks comment on primary and secondary winding 

configurations, on how testing should be required, on efficiency 

differences related to different winding configurations, and on how 

frequently transformers are operated in various winding configurations.

• Multiple kVA Ratings: Currently, DOE does not specify which kVA rating 

should be used to assess compliance in the case of distribution 

transformers with more than one kVA rating.

Issue 2: DOE requests comment on its proposal to require transformers 

with multiple nameplate kVA ratings to comply only at those ratings 

corresponding to passive cooling.
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Test Procedure Issues (Continued)

Issue 4 - DOE requests comment on its proposal to maintain the 

current test loading value requirements for all types of distribution 

transformers.

• Primary Configurations: Although DOE is considering allowing testing 

in any secondary configuration, primaries must still be tested in their 

highest loss configuration.

– Primaries exhibit larger differences in efficiency between the series and 

parallel configurations.

• Reference Loads: Currently, the reference loading points are:

– 50 percent for liquid-immersed and MVDT.

– 35 percent for LVDT.

Issue 3 - DOE requests comment on its proposal to maintain the 

requirement that transformers comply with standards for the BIL 

rating of the configuration that produces the highest losses.
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Steps in the Standards Rulemaking: 

Screening and Technology Analysis

Framework

Document

Preliminary

Analysis NOPR Final

Rule

Manufacturer

 Impact 

 Analysis

Utility

 Impact 

Analysis

Employment

 Impact

 Analysis

Life-Cycle 

Cost 

Subgroup 

Analysis

Environmental 

Assessment

Regulatory

 Impact 

Analysis

Life-Cycle

Cost &

Payback 

Period

Analyses

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date

Screening, 

Market and 

Technology

Analyses

Markups & 

Energy Use

Analysis

Shipments 

& National 

Impact

Analysis
22 | Building Technologies Program eere.energy.gov

Distribution Transformers 

Equipment Class Groupings

• There are 115 discrete kVA ratings across 10 equipment class groupings (EC):

EC Phases Voltage BIL kVA Range

1 Liquid-Immersed Single Medium --- 10-833 kVA

2 Liquid-Immersed Three Medium --- 15-2500 kVA

3 Dry-Type Single Low --- 15-333 kVA

4 Dry-Type Three Low --- 15-1000 kVA

5 Dry-Type Single Medium 20-45 kV BIL 15-833 kVA

6 Dry-Type Three Medium 20-45 kV BIL 15-2500 kVA

7 Dry-Type Single Medium 46-95 kV BIL 15-833 kVA

8 Dry-Type Three Medium 46-95 kV BIL 15-2500 kVA

9 Dry-Type Single Medium >96 kV BIL 75-833 kVA

10 Dry-Type Three Medium >96 kV BIL 225-2500 kVA

Issue 7: DOE requests comment on its proposal to keep current kVA scope.
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Rulemaking Scope:

Step-Up Transformers

Issue 8: DOE requests comment on its proposal to continue 

to not set standards for step-up transformers.

• DOE proposes to continue to not set standards for step-up 

transformers, which do not ordinarily perform power distribution 

functions.

• However, DOE is aware that step-up transformers may be used in 

place of step-down transformers and may present a potential 

loophole as standards increase.
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The negotiated rulemaking subcommittee proposed that DOE establish 

separate definitions and equipment classes for network, vault, and data 

center transformers.

• Network transformer

– Designed for use in a vault, for occasional submerged operation in 

water, and to feed a variable capacity system of interconnected 

secondary windings

– Built per the requirements of IEEE C57.12.40

• Vault-type transformer

– Designed for use in a vault and for occasional submerged operation in 

water

– Built per the requirements of IEEE C57.12.23 or IEEE C57.12.24

Rulemaking Scope: Negotiated

Rulemaking Subcommittee Proposals

Issue 9: DOE requests comment on the negotiation committee’s 

proposal to establish a separate equipment class for network/vault 

transformers and on how such transformers might be defined.
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• Data center transformer: a three-phase LVDT distribution 

transformer that:

– Is designed for use in a data center distribution system and has 

a nameplate identifying the transformer as being for this use only

– Has a maximum peak energization (or in-rush) current less than 

or equal to four times its rated full load current multiplied by the 

square root of 2, as measured certain conditions.

– Is manufactured with at least two of six additional attributes

Rulemaking Scope: Negotiated

Rulemaking Subcommittee Proposals

Issue 10: DOE requests comment on the proposal to 

establish a separate equipment class for data center 

transformers and on how such transformers might be 

defined.
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Rulemaking Scope: Negotiated

Rulemaking Subcommittee Proposals

The negotiated rulemaking subcommittee also proposed that 

DOE establish separate equipment classes for pole-mounted 

and pad-mounted liquid-immersed transformers.

Issue 11: DOE requests comment on whether separate 

equipment classes are warranted for pole-mounted, padmounted, or other types of liquid-immersed transformers.
27 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

Engineering Analysis

Framework

Document

Preliminary

Analysis NOPR Final

Rule

Manufacturer

 Impact 

 Analysis

Utility

 Impact 

Analysis

Employment

 Impact

 Analysis

Life-Cycle 

Cost 

Subgroup 

Analysis

Environmental 

Assessment

Regulatory

 Impact 

Analysis

Life-Cycle

Cost &

Payback 

Period

Analyses

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date

Shipments 

& National 

Impact

Analysis

Screening, 

Market and 

Technology

Analyses

Markups & 

Energy Use

Analysis
28 | Building Technologies Program eere.energy.gov Equipment Class Design LineType of Distribution 

Transformer

kVA 

Range Representative Unit

1

1

Liquid-immersed, 

single-phase, 

rectangular tank

10–167

50 kVA, 65°C, single-phase, 60Hz,

14400V primary, 240/120V secondary, 

rectangular tank, 95 kV BIL

2

Liquid-immersed, 

single-phase, round 

tank

10–167

25 kVA, 65°C, single-phase, 60Hz, 

14400V primary, 240/120V secondary, 

round tank, 125 kV BIL

3 Liquid-immersed, 

single-phase 250–833

500 kVA, 65°C, single-phase, 60Hz, 

14400V primary, 277V secondary, 150 

kV BIL

Liquid-Immersed Design Lines and 

Representative Units

Issue 12: DOE requests comment on setting standards 

by BIL rating for liquid-immersed distribution transformers 

as it currently does for medium voltage, dry-type units.
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Design Option Combinations:

Negotiated Rulemaking Subcommittee Input

• Step-lap mitering

– May not be cost-effective in smaller dry-type designs

– DOE removed step-lap mitering from its list of options for design 

line 6.

– Added mitering processing cost to LVDT and MVDT designs

• Core Materials

– In the U.S. market, there are few, if any, transformers built with 

ZDMH

– DOE removed ZDMH designs from its base-case scenario.
30 | Building Technologies Program eere.energy.gov

Engineering Analysis:

Materials Prices

Item and Description

2010 

Price

2011 

Price

M36 core steel (26 gauge) 0.60 0.66 

M19 core steel (26 gauge) 0.83 0.91 

M12 core steel 0.95 0.78 

M6 core steel 1.33 1.04 

M5 core steel 1.38 1.10 

M4 core steel 1.45 1.20 

M3 core steel 1.88 1.30 

M3 Lite Carlite core steel 1.95 1.95 

M2 core steel 2.00 1.40 

M2 Lite Carlite core steel 2.10 2.10 

ZDMH (mechanically-scribed core steel) 2.05 1.90 

H-0 DR core steel (laser-scribed) 2.06 1.70 

SA1 (amorphous) - finished core, volume 

production 2.38 2.20 

Impregnation (per gallon) 22.55 22.55 

Winding Combs (per pound) 12.34 12.34 

Mineral oil 3.35 3.35 

Tank Steel 0.38 0.38 
31 | Building Technologies Program eere.energy.gov

Engineering Analysis:

Materials Prices (Continued)

Issue 17: DOE requests comment on its materials prices for 

both the 2010 and 2011 cases.

Item and Description

2010 

Price

2011 

Price

Copper wire, formvar, round #10-20 4.87 4.87 

Copper wire, enameled, round #7-10 4.84 4.84 

Copper wire, enameled, rectangular sizes 4.97 4.97 

Aluminum wire, formvar, round #9-17 3.07 3.07 

Aluminum wire, formvar, round #7-10 2.57 2.57 

Copper wire, rectangular 0.1 x 0.2, Nomex

wrapped 4.52 4.52 

Aluminum wire, rectangular 0.1 x 0.2, 

Nomex wrapped 2.97 2.97 

Copper strip, thickness range 0.02-0.045 4.97 4.97 

Copper strip, thickness range 0.030-0.060 4.97 4.97 

Aluminum strip, thickness range 0.02-

0.045 2.08 2.08 

Aluminum strip, thickness range 0.045-

0.080 2.08 2.08 

Kraft insulating paper with diamond 

adhesive 1.52 1.52 

Nomex insulation (per pound) 24.50 24.50 

Cequin insulation (per pound) 5.53 5.53 
32 | Building Technologies Program eere.energy.gov

Engineering Analysis:

Scaling Results

• Costs of construction and losses can be scaled when design 

parameters are held constant, including:

– frequency, magnetic flux density, current density and insulation level.

• DOE scaled the total losses (TL) from a representative unit to other 

unanalyzed kVA ratings (S) within a design line using the following 

Scaling Rule:

TL1 = TL0 x (S1 / S0)X

• The exponent X is equal to 0.75 for ideal transformers.

• However, DOE recognized that deriving unique exponents for each 

equipment class would produce better results.
33 | Building Technologies Program eere.energy.gov

Engineering Analysis:

Scaling Exponents

• DOE instead fit a straight line in logarithmic space to selected ELs in each 

design line, producing slopes that were not equal to 0.75.

Equipment Class Scaling Exponent

1. Liquid-immersed 1-phase 0.76

2. Liquid-immersed 3-phase 0.79

3. LVDT 1-phase 0.75

4. LVDT 3-phase 0.67

5. MVDT 1-phase, low BIL 0.67

6. MVDT 3-phase, low BIL 0.67

7. MVDT 1-phase, mid-BIL 0.67

8. MVDT 3-phase, mid-BIL 0.67

9. MVDT 1-phase, high BIL 0.68

10. MVDT 3-phase, high BIL 0.68
34 | Building Technologies Program eere.energy.gov

Scaling Results:

Request for Comment

Issue 13: DOE requests comment on how best to scale 

across phase counts for each transformer type and how 

standards for either single- or three-phase transformers 

may be derived from the other type.

Issue 14: DOE requests comment on its proposal to 

scale standards to unanalyzed kVA ratings by fitting a 

straight line in logarithmic space to selected efficiency 

levels (ELs) with the understanding that the resulting line 

may not have a slope equal to 0.75.
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Engineering Design Constraints

DOE is aware that many core steels, including amorphous steels, 

have constraints on their supply.

Issue 18: DOE requests comment on the current and 

future availabilities of high-grade steels, particularly 

amorphous and mechanically-scribed steel in the United 

States.

Issue 20: DOE requests comment on its steel supply 

availability analysis, presented in Appendix 3A of the 

TSD.
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Engineering Design Constraints

DOE also understands that, particularly for liquid-immersed 

designs, larger transformers may have size or weight 

constraints that would necessitate pole replacements or 

vault expansions.

Issue 19: DOE requests comment on particular 

applications in which transformer size and weight are 

likely to be a constraint and any data that may be used to 

characterize the problem.
37 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

Markups and Energy Use

Framework

Document

Preliminary

Analysis NOPR Final

Rule

Manufacturer

 Impact 

 Analysis

Utility

 Impact 

Analysis

Employment

 Impact

 Analysis

Life-Cycle 

Cost 

Subgroup 

Analysis

Environmental 

Assessment

Regulatory

 Impact 

Analysis

Life-Cycle

Cost &

Payback 

Period

Analyses

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date

Shipments 

& National 

Impact

Analysis

Screening, 

Market and 

Technology

Analyses

Markups & 

Energy Use

Analysis
38 | Building Technologies Program eere.energy.gov

Loading: Request for Comment

Issue 21: DOE seeks comment on any additional sources of 

distribution transformer load data that could be used to validate 

the Energy Use and End-Use Load Characterization analysis. 

DOE is specifically interested in additional load data for higher 

capacity three-phase distribution transformers.

• Loading data for liquid-immersed transformers was compiled from:

– FERC Form 714 filings for 2008, which were aggregated by region were used to 

develop the price-load correlation.

– hourly metered building data were used to develop the transformer loading model

– Stakeholder submitted load data - this was used to verify loading for single-phase 

transformers

• For dry-type transformers, load data came from:

– CBECS 1992 and 1995 surveys, which sampled ~5000 commercial and industrial buildings.

– hourly metered building data were used to develop the transformer loading model
39 | Building Technologies Program eere.energy.gov

• Liquid-immersed and dry-type transformers have different distribution 

channels.

• The majority of liquid-immersed transformers are purchased by utilities directly 

from manufacturers or from the manufacturers’ representative or distributor. 

– DOE estimated the size of the direct sales distribution channel on the volume of 

electricity sales if IOUs. For direct utility purchases there is no distributor markup, this 

is estimated to occur 80% of the time.

• Dry-type transformers are purchased and installed primarily by electrical 

contractors. For dry-type transformers, markups are applied at all points in the 

distribution channel.

Distribution Channels: Markup Factors

Liquid-Immersed Dry-Type

Distributor 1.07 

(1.0 Direct Sale) Distributor 1.26(1.15 LV)

Installation Materials 1.00 Contractor Materials 1.16

(1.10 LV)

Installation Labor/Equip 1.47 Contractor Labor/Equip 1.47

Sales Tax Markup 1.069 Sales Tax Markup 1.069

Overall

1.61

(1.54 Direct Sale) 1.96 (1.79 LV)
40 | Building Technologies Program eere.energy.gov

Distribution Channels:

Markup Factors

Issue 22: DOE seeks comment on its proposed additional 

distribution channel for liquid-immersed transformers that 

estimates that approximately 80 percent of transformers 

are sold by manufacturers directly to utilities.
41 | Building Technologies Program eere.energy.gov

• Pole replacement is triggered when a transformer in the standards 

case is greater than150 pounds and 15 percent heavier then the 

transformer in the base case.

– DOE assumed that up to a maximum of 25% of total pole-mounted 

transformer population may require pole replacements.

• Replacement costs are represented as a triangular distribution with 

and average cost of $4,012 bounded by $2,025 to $5,999. This large 

distribution of possible costs is used to capture wide range of pole 

replacement circumstances and costs.

• In addition, the full cost of a pole replacement is not be attributed to 

transformer purchases, since pole lifetimes are finite.

– Pole installation costs were multiplied by a factor n/pole-lifetime, 

which approximately represents the value of the additional years of 

life. The parameter n was chosen from a flat distribution between 1 

and the pole lifetime, which was assumed to be 30 years.

Pole Replacement Costs

(Design Line 2)
42 | Building Technologies Program eere.energy.gov

Pole Replacement Costs 

(Design Line 2)

Issue 24: DOE seeks comment on its pole replacement 

methodology that is used estimate increased installation 

costs resulting from increased transformer weight due the 

proposed standard
43 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

LCC and PBP Analysis

Framework

Document

Preliminary

Analysis NOPR Final

Rule

Manufacturer

 Impact 

 Analysis

Utility

 Impact 

Analysis

Employment

 Impact

 Analysis

Life-Cycle 

Cost 

Subgroup 

Analysis

Environmental 

Assessment

Regulatory

 Impact 

Analysis

Life-Cycle

Cost &

Payback 

Period

Analyses

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date

Shipments 

& National 

Impact

Analysis

Screening, 

Market and 

Technology

Analyses

Markups & 

Energy Use

Analysis
44 | Building Technologies Program eere.energy.gov

• Some transformer purchasers assign value to losses: these purchasers are referred to 

as “Evaluators”.

• No-load loss value is defined by the parameter A ($/watt), load loss value is defined by 

the parameter B.

• Distributions for A and B were determined from survey data.

• For Evaluators, the A and B values were used to define the base case transformer 

choice, which may have an efficiency above the current standard.

• Evaluation percentages are shown in the table below.

• The evaluation rates used in the LCC analysis affect the average values (purchase cost, 

NLL, LL, PRF, RMS loading) that are carried over to the National Impact Analysis.

Customer Evaluation Rates:

Negotiated Rulemaking Subcommittee Input

 Design 

Lines

Evaluation Scenario

Nonevaluators Default All-evaluators

Liquid-immersed 1 — 5 0% 10% 100%

Low-voltage Dry-type 6 — 8 0% 2% 100%

Medium-voltage Dry-type 9 — 13B 0% 2% 100%
45 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

National Impact Analysis

Framework

Document

Preliminary

Analysis NOPR Final

Rule

Manufacturer

 Impact 

 Analysis

Utility

 Impact 

Analysis

Employment

 Impact

 Analysis

Life-Cycle 

Cost 

Subgroup 

Analysis

Environmental 

Assessment

Regulatory

 Impact 

Analysis

Life-Cycle

Cost &

Payback 

Period

Analyses

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date

Shipments 

& National 

Impact

Analysis

Screening, 

Market and 

Technology

Analyses

Markups & 

Energy Use

Analysis
46 | Building Technologies Program eere.energy.gov

Refurbished Transformers:

Request for Comment

Issue 23: DOE seeks comment on other potential changes to 

maintenance practices that could extend the service life of a 

distribution transformer.

Issue 22: DOE seeks comment on the economic criteria that a 

utility would use in making a decision to re-wind a transformer 

rather than purchase a new unit, and on the expected lifetime of a 

re-wound unit. 

DOE is aware that some utilities may purchase rewound transformers.
47 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

Other Analyses

Framework

Document

Preliminary

Analysis NOPR Final

Rule

Manufacturer

 Impact 

 Analysis

Utility

 Impact 

Analysis

Employment

 Impact

 Analysis

Life-Cycle 

Cost 

Subgroup 

Analysis

Environmental 

Assessment

Regulatory

 Impact 

Analysis

Life-Cycle

Cost &

Payback 

Period

Analyses

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date

National

 Impact

Analysis

Screening, 

Market and 

Technology

Analyses

Markups & 

Energy Use

Analysis

DOE has no 

specific requests 

for comment on 

the analyses 

circled above.
48 | Building Technologies Program eere.energy.gov

Liquid-Immersed Trial Standard 

Levels (TSLs)

There are 7 TSLs for liquid-immersed distribution transformers:

• A diversity of core materials are costcompetitive and economically feasible 

for all design lines. TSL 1

TSL 2 • EL 1 for all design lines.

• Maximum efficiency achievable with TSL 3 M3 steel.

TSL 4 • Maximum NPV with 7% discounting.

TSL 5 • EL 3 for all design lines.

• Maximum source energy savings with TSL 6 positive NPV (7% discounting).

• Maximum technologically feasible TSL 7 (max tech).
49 | Building Technologies Program eere.energy.gov

LVDT Trial Standard Levels (TSLs)

There are 6 TSLs for LVDT distribution transformers:

• Maximum efficiency achievable TSL 1 with M6 steel.

TSL 2 • NEMA Premium levels.

• Maximum efficiency achievable 

using butt-lap core mitering for 

single-phase designs and full 

mitering for three-phase designs.

TSL 3

• Maximum NPV with 7% TSL 4 discounting.

• Maximum source energy savings 

with positive NPV (7% 

discounting). TSL 5

• Maximum technologically feasible TSL 6 (max tech).
50 | Building Technologies Program eere.energy.gov

MVDT Trial Standard Levels (TSLs)

There are 5 TSLs for MVDT distribution transformers:

TSL 1 • EL 1 for all design lines.

• A diversity of core materials are 

cost-competitive and economically 

feasible for all design lines. TSL 2

• Maximum NPV with 7% TSL 3 discounting.

• Maximum source energy savings 

with positive NPV (7% 

discounting). TSL 4

• Maximum technologically feasible TSL 5 (max tech).

Negotiated

Consensus
51 | Building Technologies Program eere.energy.gov

• DOE is proposing TSL 1 for liquid-immersed distribution 

transformers:

Proposed Energy Conservation 

Standards: Liquid-Immersed

1-Phase (Equipment Class 1) 3-Phase (Equipment Class 2)

kVA Efficiency (%) kVA Efficiency (%)

10 98.70 15 98.65

15 98.82 30 98.83

25 98.95 45 98.92

37.5 99.05 75 99.03

50 99.11 112.5 99.11

75 99.19 150 99.16

100 99.25 225 99.23

167 99.33 300 99.27

250 99.39 500 99.35

333 99.43 750 99.40

500 99.49 1000 99.43

667 99.52 1500 99.48

833 99.55 2000 99.51

2500 99.53
52 | Building Technologies Program eere.energy.gov

• DOE is proposing TSL 1 for LVDT distribution transformers:

Proposed Energy Conservation 

Standards: LVDT

1-Phase (Equipment Class 3) 3-Phase (Equipment Class 4)

kVA Efficiency (%) kVA Efficiency (%)

15 97.73 15 97.44

25 98.00 30 97.95

37.5 98.20 45 98.20

50 98.31 75 98.47

75 98.50 112.5 98.66

100 98.60 150 98.78

167 98.75 225 98.92

250 98.87 300 99.02

333 98.94 500 99.17

750 99.27

1000 99.34
53 | Building Technologies Program eere.energy.gov

• DOE is proposing TSL 2 for MVDT distribution transformers:

Proposed Energy Conservation Standards: 

MVDT (Negotiated Consensus)

EC 5 EC 6 EC 7 EC 8 EC 9 EC 10

kVA % kVA % kVA % kVA % kVA % kVA %

15 98.10 15 97.50 15 97.86 15 97.18

25 98.33 30 97.90 25 98.12 30 97.63

37.5 98.49 45 98.10 37.5 98.30 45 97.86

50 98.60 75 98.33 50 98.42 75 98.13

75 98.73 112.5 98.52 75 98.57 112.5 98.36 75 98.53

100 98.82 150 98.65 100 98.67 150 98.51 100 98.63

167 98.96 225 98.82 167 98.83 225 98.69 167 98.80 225 98.57

250 99.07 300 98.93 250 98.95 300 98.81 250 98.91 300 98.69

333 99.14 500 99.09 333 99.03 500 98.99 333 98.99 500 98.89

500 99.22 750 99.21 500 99.12 750 99.12 500 99.09 750 99.02

667 99.27 1000 99.28 667 99.18 1000 99.20 667 99.15 1000 99.11

833 99.31 1500 99.37 833 99.23 1500 99.30 833 99.20 1500 99.21

2000 99.43 2000 99.36 2000 99.28

2500 99.47 2500 99.41 2500 99.33
54 | Building Technologies Program eere.energy.gov

• Energy Savings:

– 1.58 quads over 30 years (2016-2045)

– Eliminate the need for 2.4 GW of generating capacity by 2045

• Cost Savings:

– Cumulative Net Present Value ranges from $2.9 billion (7% 

discount rate) to $12.1 billion (3% discount rate).

• Environmental Benefits:

– CO2 emission reduction of 122.1 Mt

– NOX emission reduction of 99.7 kt

– Hg emission reduction of 0.819 ton

Summary of Proposed Rule Impacts
55 | Building Technologies Program eere.energy.gov

Discount Rate Primary 

Estimate*

Low Net 

Benefits 

Estimate*

High Net 

Benefits 

Estimate*

Monetized (million 2010$/year)

Operating Cost Savings

7% 631 594 659

3% 1,026 950 1,075

CO2 Reduction at $4.9/t 5% 58.6 58.6 58.6

CO2Reduction at $22.3/t 3% 244 244 244

CO2Reduction at $36.5/t 2.5% 389 389 389

CO2Reduction at $67.6/t 3% 742 742 742

NOX Reduction at $2,537/ton

7% 7.78 7.78 7.78

3% 12.4 12.4 12.4

Total†

7% plus CO2 range 697 to 1380 660 to 1343 726 to 1409

7% 883 846 911

3% plus CO2 range 1097 to 1780 1021 to 1704 1146 to 1829

3% 1,283 1,207 1,331

Costs

Incremental Product Costs

7% 302 338 285

3% 308 351 289

Total Net Benefits

Total

7% plus CO2 range 400 to 1083 327 to 1010 445 to 1128

7% 581 507 626

3% plus CO2 range 789 to 1472 670 to 1353 857 to 1540

3% 975 855 1,043

Summary of Annualized Benefits and 

Costs of Proposed Standards
56 | Building Technologies Program eere.energy.gov

• In all correspondence, please refer to the Distribution Transformers 

rulemaking by:

– Distribution Transformers Rulemaking,

– Docket Number EE–2010–BT–STD–0048 , and

– Regulatory Identification Number (RIN) 1904–AC04 

• Email: DistributionTransformers-2010-STD-0048@ee.doe.gov 

• Comment period closes: April 10, 2012

How to Submit Written Comments

Postal: Hand Delivery/Courier:

Ms. Brenda Edwards

U.S. Department of Energy

Building Technologies Program, Mailstop EE-2J

1000 Independence Avenue, SW

Washington, DC 20585-0121

Ms. Brenda Edwards

U.S. Department of Energy

Building Technologies Program, Suite 600

950 L’Enfant Plaza, SW

Washington, DC 20024

Tel: 202-586-2945