1 | Building Technologies Program eere.energy.gov

The Parker Ranch installation in Hawaii

BUILDING TECHNOLOGIES PROGRAM

Distribution Transformers

Energy Conservation Program

Preliminary Analysis

James Raba

U.S. Department of Energy

Energy Efficiency & Renewable Energy

Jim.Raba@ee.doe.gov

April 5, 2011
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• 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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Morning Agenda

9:00 – 9:05 am Welcome

9:05 – 9:20 am Introductions, Agenda Review, and Opening Statements

9:20 – 9:25 am Regulatory History

9:25 – 9:30 am Rulemaking Overview and Scope of Coverage

9:30 – 10:00 am Test Procedure

10:00 – 10:15 am Break

10:15 – 11:00 am Market and Technology Assessment and Screening Analysis

11:00 – 12:00 pm Engineering Analysis

12:00 – 1:00 pm Lunch
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Afternoon Agenda

1:00 – 1:15 pm Markups for Product Price Determination

1:15 – 1:45 pm Energy Use and End-Use Load Characterization

1:45 – 2:15 pm Life-Cycle Cost and Payback Period Analysis

2:15 – 2:45 pm Shipments and National Impacts Analysis

2:45 – 3:00 pm Break

3:00 – 3:15 pm Preliminary Manufacturer Impact Analysis

3:15 – 3:30 pm NOPR Analyses

3:30 – 4:00 pm Closing Remarks
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Markup Analysis; Energy Use & End-Use Load

National Impact Analysis

Public Meeting Agenda

1 Overview

4

2

3 Market & Tech; Screening; Engineering

6

5

Test Procedure

Life-Cycle Cost and Payback Period Analysis

7 Preliminary MIA; NOPR Analyses
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• Present the procedural and analytical approaches to evaluate 

energy conservation standards for distribution transformers.

• Provide a forum for public discussion of rulemaking issues.

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

comments.

• Inform interested parties and facilitate the rulemaking process.

Purpose of the Preliminary Analysis 

Public Meeting
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Issues for Comment

Issue Box The Department welcomes comments, data, 

and information regarding distribution transformer energy 

conservation standards. 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 three in the executive 

summary of the preliminary TSD. Nonetheless, 

comments concerning any part of the document or 

presentation are welcome.
8 | 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 18, 2011

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
9 | Building Technologies Program eere.energy.gov

Regulatory History

• Title III, Part C of the Energy Policy and 

Conservation Act of 1975 (EPCA) (Public Law 94-

163) established the ―Energy Conservation Program 

for Certain Industrial Equipment,‖ including 

distribution transformers.

• Energy Policy Act (EPACT) of 1992 (Public Law 

102-486) directed DOE to establish energy 

conservation standards for distribution transformers.

• EPACT 2005 set standards for low-voltage dry-type 

(LVDT) distribution transformers at the NEMA TP 1-

2002 level.
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• October 2007 – DOE issued a Final Rule establishing energy conservation 

standards for liquid-immersed and medium-voltage dry-type (MVDT) 

distribution transformers. (72 FR 58190)

• As a result of a settlement agreement, DOE has an expedited timeline to 

determine whether to amend standards for liquid-immersed and MVDT 

distribution transformers.

• DOE must publish by October 1, 2011 either:

– A determination that the standards do not need to be amended, or

– A Notice of Proposed Rulemaking (NOPR) including any proposed standards.

• If DOE publishes a NOPR, it must publish a Final Rule by October 1, 

2012.

Regulatory History (Continued)
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Regulatory History (Continued)

Test Procedure

• On April 27, 2006, DOE codified a test procedure final rule for distribution 

transformers in 10 CFR Part 431, Appendix A to Subpart K, ―Uniform Test 

Method for Measuring the Energy Consumption of Distribution 

Transformers.‖ 71 FR 24972

– Based on NEMA TP 2-1998.

• The Energy Independence and Security Act 2007 (EISA) requires 

that DOE amend each test procedure within seven years of its 

original publication. (42 U.S.C. 6314(a)(1))

• DOE also intends to review its test procedure concurrently with the 

energy conservation standards.
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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: 

Preliminary Analysis

Framework

Document

Preliminary

Analysis NOPR Final

Rule

Market & 

Technology 

Assessment

Screening 

Analysis

Engineering

Analysis

Energy Use and 

End-Use Load 

Characterization

Shipments

Analysis

National

Impact

Analysis

Markups for 

Product Price 

Determination

Life-Cycle

Cost and

Payback 

Period Analysis

Preliminary 

Manufacturer 

Impact Analysis

Compliance 

Date
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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

National

Impact

Analysis

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date
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Analyses for Final Rule

Framework

Document NOPR Final 

Rule

Revise NOPR 

Analyses

Preliminary 

Analysis
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Distribution Transformers 

Rulemaking Schedule

2011 2012 2013 2014 2015 2016

Milestone Date

Federal Register Notice of Public Meeting and Availability 

of the Preliminary Technical Support Document

March 2, 2011

Issue NOPR or Determination October 2011

Issue Final Rule October 2012

Compliance Date January 2016
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Distribution Transformers 

Rulemaking Schedule

Issue: The Department welcomes comment on the time 

necessary for the industry to implement amended energy 

conservation standards if DOE chooses to amend 

standards. Specifically, would a compliance date prior to 

January 1, 2016 be feasible, and if not, why?

• If DOE finds that amended standards are warranted, the compliance date 

of any amended standards must be no later than January 1, 2016.

– DOE may select a compliance date prior to January 1, 2016.
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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 Related 

Statutory 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.
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Distribution Transformers Related 

Statutory Definitions (Continued)

•  ̳Liquid-immersed distribution transformer‘ means a distribution 

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

insulating liquid.

•  ̳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.

•  ̳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.
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Markup Analysis; Energy Use & End-Use Load

National Impact Analysis

Public Meeting Agenda

1 Overview

4

2

3 Market & Tech; Screening; Engineering

6

5

Test Procedure

Life-Cycle Cost and Payback Period Analysis

7 Preliminary MIA; NOPR Analyses
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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:

Dual/Multiple-Voltage Secondaries

• Some transformers have secondary windings that can be connected 

either in series or in parallel.

• Reconfigurable secondaries are most commonly used in low kVA, singlephase, liquid-immersed, pole-mounted units.

• The test procedure currently states that efficiency must be tested at 

voltage with highest losses, which is usually in parallel.

• Some MVDT transformers may have different BIL ratings in different 

configurations.

• DOE proposes allowing manufacturers to meet amended energy 

conservation standards in any secondary configuration and at the lowest 

BIL.
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Test Procedure (Continued):

Dual/Multiple-Voltage Secondaries

Issue 1: DOE seeks comment on its proposal to amend the 

test procedure to allow compliance testing in any secondary 

configuration. Should the proposed amendment apply to all 

covered distribution transformers or a subset of 

transformers? DOE welcomes the submission of any data 

that would support a conclusion.

Issue 3: DOE welcomes comment on its proposal to require 

compliance at the lowest basic impulse levels (BILs) that a 

dual/multiple-voltage distribution transformer is rated for 

operation.
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Test Procedure (Continued):

Other Topics of Interest

Issue 4 - DOE welcomes comment on all aspects of the 

current test procedure for distribution transformers.

• 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.

• Currently, the reference loading points are:

– 50 percent for liquid-immersed and MVDT.

– 35 percent for LVDT.
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Markup Analysis; Energy Use & End-Use Load

National Impact Analysis

Public Meeting Agenda

1 Overview

4

2

3 Market & Tech; Screening; Engineering

6

5

Test Procedure

Life-Cycle Cost and Payback Period Analysis

7 Preliminary MIA; NOPR Analyses
27 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

Preliminary Analysis

Framework

Document

Preliminary

Analysis NOPR Final

Rule Date

Screening

Analysis

Engineering

Analysis

Energy Use and 

End-Use Load 

Characterization

Shipments

Analysis

National

Impact

Analysis

Markups for 

Equipment Price 

Determination

Life-Cycle

Cost and

Payback 

Period Analysis

Market & 

Technology 

Assessment

Preliminary 

Manufacturer 

Impact Analysis

Compliance 

Date
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Purpose

• Market and Technology Assessment

– Characterize the distribution transformer market and industry.

– Identify the technology options to improve distribution transformer 

efficiency.

– Establish equipment classes.

• Screening Analysis

– Screen out technology options that DOE will not consider in the 

engineering analysis for distribution transformers based on several criteria.
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Relationship of Market and Technology 

Assessment to Other Analyses

Market and Technology 

Assessment Equipment Classes

Technology options to improve efficiency

Screening Analysis

Design options to improve efficiency

Engineering Analysis
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Equipment Classes

• DOE divides covered equipment into classes by:

– The Type of energy used,

– The Capacity, or

– Any performance-related features that affect consumer utility or 

efficiency.

• DOE considered 10 equipment class groupings by dividing the 

population of distribution transformers based upon:

– Type of transformer insulation: liquid-immersed or dry-type,

– Number of phases: single or three,

– Voltage class: low or medium (for dry-type units only), and

– Basic impulse insulation level (BIL): (for MVDT units only).
31 | Building Technologies Program eere.energy.gov

Distribution Transformers 

Equipment Class Groupings

There are 115 discrete kVA ratings across the ten equipment class groupings (ECG)

ECG Insulation 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
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Distribution Transformers

2009 Industry Shipments

Equipment Class Grouping Units 

Shipped

MVA 

Capacity 

Shipped

1. Liquid-immersed, medium-voltage, single-phase 683,726 21,994

2. Liquid-immersed, medium-voltage, three-phase 49,739 32,266

3. Dry-type, low-voltage, single-phase 17,740 647

4. Dry-type, low-voltage, three-phase 206,929 15,778

5. Dry-type, medium-voltage, single-phase, 20-45 kV BIL 709 23

6. Dry-type, medium-voltage, three-phase, 20-45 kV BIL 522 257

7. Dry-type, medium-voltage, single-phase, 46-95 kV BIL 546 23

8. Dry-type, medium-voltage, three-phase, 46-95 kV BIL 2,074 3,655

9. Dry-type, medium-voltage, single-phase, ≥ 96 kV BIL 202 9

10. Dry-type, medium-voltage, three-phase, ≥ 96 kV BIL 1,286 2,206

TOTAL 963,473 76,858
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Technology Options

Technology Option Material / Concept

Conductor Materials for Coils

Aluminum (wire and sheet)

Copper (wire and sheet)

Core Materials

Cold-Rolled High Silicon (CRHiSi) Steel

CRHiSi Domain-Refined Steels

Amorphous Materials in Wound Core

Geometry Modifications Adjust the cross-sectional area of the 

core/conductor, or adjust volts per turn

Symmetric Core Designs Continuously wound cores with 120 degree

radial symmetry for three-phase designs

Core Deactivation Technology

A transformer is replaced by three smaller 

transformers that are (de)activated in 

response to changes in load demand.
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• ―Symmetric Core‖ designs are three-phase 

designs that use a continuously wound 

core with 120° radial symmetry.

• Advantages include lowered: weight, 

volume, no-load losses, noise, vibration, 

stray magnetic fields, inrush current, and 

power in the third harmonic.

• Best suited for delta-delta or delta-wye 

connections, though zero-sequence fluxes 

associated with wye-wye connections can 

be mitigated by a delta-connected tertiary 

winding.

Technology Assessment:

Symmetric Core Designs

Source: Lundmark, Sonja. “Computer Model of 

Electromagnetic Phenomena in Hexaformer.” 2007. 

http://www.hexaformer.com/ExternaDokument/chalmers_re

port1.pdf.
35 | Building Technologies Program eere.energy.gov

Symmetric Core Designs:

Request for Comment

Issue 5: DOE seeks comment on symmetric core 

designs, their practicability to manufacture and install, 

and whether they offer potential for efficiency 

improvement. In particular, DOE seeks comment on any 

application types in which using a symmetric core design 

may be infeasible. DOE also seeks comment on any 

intellectual property concerns related to this technology 

and the feasibility of manufacturing it on a large scale. 
36 | Building Technologies Program eere.energy.gov

• Reduces core losses by using a system of smaller transformers to 

replace a single, larger transformer.

– Example: Three 25 kVA transformers in parallel replace a 75 kVA 

transformer.

• Control unit can activate and deactivate component transformers 

depending on the loading demands.

– Optimizes combination of transformers at given load.

• DOE is only aware of this technology in LVDT distribution 

transformers.

– Medium-voltage core deactivation systems have not been produced 

commercially, and pose difficulties for switching within the primary and 

secondary connections.

• Best suited for applications with low loading demands.

Technology Assessment:

Core Deactivation Technology
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Core Deactivation Technology

Load vs. Efficiency

This figure is for illustrative purposes only, and is not based on actual 

DOE research

9 3

9 4

9 5

9 6

9 7

9 8

9 9

5 1 5 2 5 3 5 4 5 5 5 6 5 7 5 8 5 9 5

Efficiency %

Percentage of Full Rated Load

Core Deactivation System

Traditional Transformer Design

Test Procedure Loading
38 | Building Technologies Program eere.energy.gov

• While core deactivation technology could save energy over a load 

cycle, these energy savings may not be captured by the current test 

procedure specifying a single load factor.

• A weighted-average loss calculation using various loadings could 

better capture this technology‘s energy savings potential.

Example:

Technology Assessment:

Core Deactivation Technology

Loading 

(%)

Losses 

(W)

Single Loading Point,

Load Frequency (%)

Weighted Average,

Load Frequency (%)

0 200.0 0 31

15 222.5 0 22

35 322.5 100 20

50 450.0 0 18

75 762.5 0 9

Average Losses 322.5 322.5
39 | Building Technologies Program eere.energy.gov

• DOE did not analyze core deactivation technology for the preliminary 

analysis, but intends to analyze it for the NOPR.

– Scale each design to 1/3 its kVA and group them in sets of three.

– Account for additional cost and weight of the core deactivation technology.

– Analyze each core deactivation system using various loading scenarios.

• Core deactivation systems using non-identical component transformers.

– Each component transformer requires a similar winding design to maintain 

impedance at each loading.

• Based on conversations with manufacturers, core deactivation with 

MVDT has additional challenges.

Technology Assessment:

Core Deactivation Technology
40 | Building Technologies Program eere.energy.gov

Technology Assessment:

Core Deactivation Technology

Issue 6: DOE seeks comment on core deactivation 

technology. DOE requests input on any considerations 

necessary for analyzing core deactivation systems composed 

of different component transformers. DOE also seeks 

comment on the types of applications that might benefit from 

using the technology, and any other considerations related to 

the incorporation of the technology into the test procedure.

Issue 3: DOE seeks comment on its proposal to designate a 

weighted-average loss calculation using various loadings to 

capture the energy savings potential of technologies that do 

not follow the loading vs. losses relationship evident in 

traditional transformer designs. DOE welcomes comment on 

the appropriate weightings to use for the different load 

factors.
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Screening Analysis

Impacts on health or safety

Adverse impacts on equipment utility or availability to 

consumers

Practicability to manufacture, install, and service

Technological feasibility

Purpose

• Screen out technology options that DOE will not consider in the 

engineering analysis for distribution transformers.

Approach

• DOE will evaluate each technology option based on the following criteria:
42 | Building Technologies Program eere.energy.gov

Technology Options Screened 

Out of the Analysis

Technology Option Excluded Screening Criteria

Silver as a Conductor Material Practicability to manufacture, install, and service

High-Temperature 

Superconductors

Technological feasibility; 

Practicability to manufacture, install, and service

Amorphous Core Material in 

Stacked Core Configuration

Technological feasibility; 

Practicability to manufacture, install, and service

Carbon Composite Materials 

for Heat Removal Technological feasibility

High-Temperature Insulating 

Material Technological feasibility

Solid-State (Power Electronics) 

Technology

Technological feasibility;

Practicability to manufacture, install, and 

service.

Nanotechnology Composites Technological feasibility
43 | Building Technologies Program eere.energy.gov

Technology Options Screened Out of 

the Analysis – Request for Comment

Issue: DOE invites comment on the technology options 

tentatively eliminated during the screening analysis. DOE 

also welcomes comment on any proprietary concerns 

relevant to the design options considered in the analysis.

Issue 6.1: DOE knows of no current commercial efforts or 

prototype designs that employ nanotechnology composites in 

distribution transformers, but welcomes comment on such 

technology and its implications for the future of the industry.
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Steps in the Standards Rulemaking: 

Preliminary Analysis

Framework

Document

Preliminary

Analysis NOPR Final

Rule Date

Screening

Analysis

Engineering

Analysis

Energy Use and 

End-Use Load 

Characterization

Shipments

Analysis

National

Impact

Analysis

Markups for 

Equipment Price 

Determination

Life-Cycle

Cost and

Payback 

Period Analysis

Market & 

Technology 

Assessment

Preliminary 

Manufacturer 

Impact Analysis

Compliance 

Date
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Goals of the Engineering Analysis

Downstream Analyses

• Life-Cycle Cost and 

Payback Period Analysis

• National Impact Analysis

Manufacturer Selling Price –

Efficiency Relationship

Manufacturer 

Selling Price

Efficiency Level

• To evaluate design options that improve efficiency.

• To characterize manufacturer selling price (MSP) versus 

efficiency for higher-efficiency distribution transformers.
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Engineering Analysis:

Methodology

 Subdivide 10 equipment class groupings into 13 design lines 

based on similar principles of design. Identify rep units. 

 Identify design option combinations to characterize the 

spectrum of possible efficiencies.

 Identify materials prices, markups, labor requirements, and 

other cost components for each design option combination.

 Use Optimized Program Service (OPS) software to model 

optimized designs based on several hundred A and B values.

 Develop candidate standard levels (CSLs) that span the range 

of efficiency from the baseline to the maximum technologically 

feasible.

 Scale results to other equipment classes not analyzed.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Model Optimized 

Designs Based 

on A’s and B’s

Develop CSLs

Scale to 

Equipment 

Classes Not 

Analyzed
47 | Building Technologies Program eere.energy.gov

Engineering Design Lines and 

Representative Units

• Subdivide equipment classes into 13 engineering 

design lines based on similar principles of design 

and construction.

– Five liquid-immersed,

– Three LVDT, and

– Five MVDT.

• Span a range of kVA ratings for which the 0.75 

scaling rule would provide accurate results.

• Select one representative unit from each engineering 

design line.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Scale to 

Equipment 

Classes Not 

Analyzed
48 | Building Technologies Program eere.energy.gov

Liquid-Immersed Equipment Class to 

Design Line Mapping

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Scale to 

Equipment 

Classes Not 

Analyzed

Rectangular Round

Tank Tank

10

15

25

37.5

50

75

100

167

250

333

500

667

833

Equipment Class Group 1

Liquid-Immersed,

Single-Phase

kVA

DL 1DL 2 DL 3

Rep Unit

Rep Unit

Rep Unit

Design

Lines

15

30

45

75

112.5

150

225

300

500

750

1000

1500

2000

2500

Equipment Class Group 2

Liquid-Immersed,

Three-Phase

kVA

DL 4 DL 5

Rep Unit

Rep Unit
49 | Building Technologies Program eere.energy.gov Equipment Class Design Line

Type 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

2

Liquid-immersed, 

single-phase, round 

tank

10–167

25 kVA, 65°C, single-phase, 60Hz, 

14400V primary, 240/120V secondary, 

round tank

3

Liquid-immersed, 

single-phase 250–833 500 kVA, 65°C, single-phase, 60Hz, 14400V primary, 277V secondary

Liquid-Immersed Design Lines and 

Representative Units

Issue 7: DOE welcomes comment on the representative 

units selected for the single-phase, liquid-immersed units 

in design lines 1 through 3. Specifically, DOE seeks 

comment on its decision to use a 14400V primary voltage 

for design lines 1 through 3.
50 | Building Technologies Program eere.energy.gov

Design Lines 5 and 13:

Representative Units

Issues 8 & 9: DOE welcomes comment on the 

representative units selected for design lines 5 and 13. 

Specifically, DOE requests comment on the appropriate 

primary voltage for analyzing these representative units.

Equipment 

Class

Design 

Line

Type of Distribution 

Transformer

kVA 

Range Representative Unit

2 5

Liquid-immersed, 

three-phase 750–2500

1500 kVA, 65°C, three-phase, 60Hz, 

24940GrdY/14400V primary, 

480Y/277V secondary

10 13

Dry-type, mediumvoltage, three-phase, 

96-150kV BIL

225–2500

2000 kVA, 150°C, three-phase, 60Hz, 

12470V primary, 480Y/277V 

secondary, 125kV BIL
51 | Building Technologies Program eere.energy.gov

Design Lines and Representative 

Units

Issue 10: DOE welcomes comment on additional 

representative units or design lines that should be 

considered in its analysis. DOE welcomes comment on 

all aspects of its tentatively selected representative units 

and design lines.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Scale to 

Equipment 

Classes Not 

Analyzed
52 | Building Technologies Program eere.energy.gov

Identify Transformer Design Option 

Combinations

• Select design option combinations.

– Vary core configurations, core steels, and winding materials.

– Capture most common designs and maximum efficiency.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Design Option Designs Considered

Core Configuration 

(Type)

Wound core distributed gap;

Stacked butt-lap;

Stacked full miter;

Stacked cruciform miter.

Core Configuration 

(Construction)

1-Phase: Shell and Core type.

3-Phase: 3-legged, 5-legged and Symmetric Core.

Core Steels

Silicon steel: M12, M6, M5, M4, M3, M2.

Domain refined silicon steel: H-0 DR (dry-type), 

ZDMH (liquid-immersed).

Amorphous steel: SA1 (Dry-type and Liquid)

Winding materials Copper;

Aluminum.

Scale to 

Equipment 

Classes Not 

Analyzed
53 | Building Technologies Program eere.energy.gov

Identify Transformer Design Option 

Combinations (Continued)

Design 

Option

Core 

Material

Conductor 

Primary

Conductor 

Secondary

Core/Coil Design 

Type

1 M12 Al Al 3-leg stacked butt-lap

2 M12 Cu Al 3-leg stacked butt-lap

3 M6 Al Al 3-leg stacked butt-lap

4 M6 Al Al 3-leg stacked full miter

5 M4 Cu Al 3-leg stacked full miter

6 M3 Al Al 3-leg stacked full miter

7* H-0 DR Al Al 3-leg stacked full miter

8 H-0 DR Cu Cu 3-leg stacked full miter

9* SA1 Al Al 5-leg distributed gap core

10 SA1 Cu Cu 5-leg distributed gap core

* Note: Designs 7 and 9 are supplementary and not included in downstream 

analyses.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Example of Design Option Combinations Analyzed

DL7: 75 kVA low-voltage dry-type, three-phase.

Scale to 

Equipment 

Classes Not 

Analyzed
54 | Building Technologies Program eere.energy.gov

Identify Transformer Design Option 

Combinations (Continued)

Issue 12: DOE seeks comment on the design option 

combinations tentatively selected for analyzing each 

design line. DOE would like comments on any additional 

design option combinations that would yield efficiency 

ratings greater than the domain-refined steels used in 

DOE‘s analysis. DOE considered ZDMH for liquidimmersed designs and H-0 DR for dry-type designs.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Scale to 

Equipment 

Classes Not 

Analyzed
55 | Building Technologies Program eere.energy.gov

Engineering Analysis:

Markups and Labor Rate

• DOE determined materials prices and labor requirements 

through conversations with manufacturers and experts.

• DOE determined markups and labor rates from census 

data, SEC filings, and manufacturer interviews.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Markup / Cost Input Markup Notes

Scrap and handling

2.5 % Standard scrap and handling; applied to 

materials

1.5 % Prefabricated amorphous cores

4.0 % Additional scrap on fully mitered cores

Factory overhead 12.5 % Applied to materials

Shipping $ 0.22 /

pound

Added prior to profit markup; Approximately 

4–8% of MSP

Fully-burdened hourly 

labor rate $ 51.52 Applied to total labor hours

Non-production 25 % Applied to total cost for SG&A, R&D, 

warranty/risk provisions, and profit factor

Scale to 

Equipment 

Classes Not 

Analyzed
56 | Building Technologies Program eere.energy.gov

Engineering Analysis:

Markups and Labor Rate

Issue 13: DOE used 2010 materials prices for its analysis, and 

conducted high-price and low-price sensitivities using 2008 and 

2006 materials prices, respectively. DOE requests comment on 

its tentative decision to consider the current (2010) materials 

prices as the reference case materials price rather than a fiveyear average price.

Choose Rep. 

Design Lines and 

Units

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Scale to 

Equipment 

Classes Not 

Analyzed

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs Issue 14: DOE welcomes comment on its tentative decision to 

use the same factory overhead markup for designs using a 

prefabricated amorphous core as for designs for which the 

manufacturer produces the core. 

Issue 15: DOE welcomes comment on its tentative decision to 

include shipping costs in the engineering analysis as a 

component of the manufacturer‘s selling price. DOE seeks 

comment on whether profit markups are applied to the shipping 

cost, and if shipping costs are typically 4-8% of total revenue for 

the sale of distribution transformers.
57 | Building Technologies Program eere.energy.gov

Engineering Analysis:

Markups and Labor Rate

Issue 16: DOE seeks comment on the additional costs 

considered for amorphous designs in DLs 10, 12, and 13. 

Additionally, DOE seeks comment on whether these 

additional costs apply to liquid-immersed design lines that 

are 1500 kVA or greater.

• For large (1500 kVA or greater) dry-type designs using an 

amorphous core, DOE accounted for additional labor and 

hardware costs.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Scale to 

Equipment 

Classes Not 

Analyzed

Model Optimized 

Designs Based 

on A’s and B’s

Cost Factor Additional Amount 

per Design Rationale

Labor 10 hours Extra handling required for 

large, fragile amorphous cores.

Hardware $230 to $330

Additional bracing necessary in 

large designs to contain the coil 

and prevent short circuit

problems.
58 | Building Technologies Program eere.energy.gov

Engineering Analysis:

Modeling Optimized Designs

• Optimized Program Service (OPS) software conducts 

design runs.

• As an input to the OPS software, economic parameters 

(A and B values) are varied to simulate a range of 

customer orders, creating a database of transformer 

designs.

• Approximately 2,500 unique designs for each of the 

thirteen representative units within each of the thirteen 

design lines.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Scale to 

Equipment 

Classes Not 

Analyzed
59 | Building Technologies Program eere.energy.gov

Engineering Analysis:

Modeling Optimized Designs

• OPS design software output includes:

– Construction and winding instructions for the core and coil 

(e.g., core dimensions, high- and low-voltage windings, tap 

locations, insulation, cooling ducts, and labor).

– Bill of materials and electrical analysis report.

• Material, labor costs and markups are combined to 

determine the manufacturer‘s selling price (MSP).

• Temperature-corrected efficiency determined from OPS 

software electrical analysis report.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Scale to 

Equipment 

Classes Not 

Analyzed
60 | Building Technologies Program eere.energy.gov

Engineering Analysis:

Modeled Designs from DL1

Rep Unit from DL1: 50 kVA liquid-immersed, single-phase, pad-mounted

$1,000 

$1,500 

$2,000 

$2,500 

$3,000 

$3,500 

$4,000 

$4,500 

99.00% 99.10% 99.20% 99.30% 99.40% 99.50% 99.60% 99.70%

Manufacturer Selling Price ($)

Efficiency at 50% Load, Temperature Corrected

M5CuAl_sh

M3AlAl_sh

M3CuAl_sh

M2AlAl_sh

M2CuAl_sh

ZDMHAlAl_sh

ZDMHCuCu_sh

SA1AlAl_sh

SA1CuCu_sh

Current Standard Level
61 | Building Technologies Program eere.energy.gov

• DOE was unable to identify a company that could model 

symmetric core designs.

• DOE gathered information on symmetric cores through 

manufacturer interviews, published literature, and limited 

designs provided by manufacturers.

– Using these data sources, DOE roughly estimated the costefficiency relationship of symmetric core designs.

• Adjusted traditional core designs to simulate a symmetric 

core design:

Engineering Analysis:

Symmetric Core Designs

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Adjustment Amount

Reduced core losses -15.5%

Reduced core weight -17.5%

Increased labor costs +55.0%

Scale to 

Equipment 

Classes Not 

Analyzed
62 | Building Technologies Program eere.energy.gov

Engineering Analysis:

Symmetric Core Designs

Issue 5: DOE requests comment on the adjustments 

used to estimate symmetric core cost-efficiency 

relationships, and welcomes any performance data 

generated from simulation or testing that demonstrate the 

performance of symmetric core designs.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Scale to 

Equipment 

Classes Not 

Analyzed
63 | Building Technologies Program eere.energy.gov

Engineering Analysis:

Develop Candidate Standard Levels

• DOE identified candidate standard levels (CSLs) that span 

the range of distribution transformer efficiencies from the 

baseline to the maximum technologically feasible efficiency.

• Factors DOE considered in setting CSLs:

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Benchmark efficiency levels (e.g., NEMA Premium)

Equally spaced efficiency increments

Harmonization across single-phase and the per-phase 

kVA equivalent three-phase design lines.

Scale to 

Equipment 

Classes Not 

Analyzed
64 | Building Technologies Program eere.energy.gov

Engineering Analysis:

CSLs for DL1 (50 kVA, 1-phase)

$1,500 

$2,000 

$2,500 

$3,000 

$3,500 

$4,000 

$4,500 

$5,000 

99.00% 99.10% 99.20% 99.30% 99.40% 99.50% 99.60% 99.70%

Manufacturer Selling Price ($)

Efficiency at 50% Load, Temperature Corrected

M5CuAl_sh

M3AlAl_sh

M3CuAl_sh

M2AlAl_sh

M2CuAl_sh

ZDMHAlAl_sh

ZDMHCuCu_sh

SA1AlAl_sh

SA1CuCu_sh

CSLs

CSL 0 CSL 1 CSL 2 CSL 3 CSL 4 CSL 5 CSL 6
65 | Building Technologies Program eere.energy.gov

Developing Trial Standard Levels for 

the NOPR

• If DOE issues a NOPR, it will select trial standard levels 

(TSLs) based on groupings of CSLs, such as:

– Per-phase harmonization, minimum LCC, and maximum NPV.

• These TSLs may consider any interaction between 

equipment classes.

• DOE will select its proposed standard level in the NOPR 

from the list of TSLs developed.

Issue 17: DOE invites comment on the criteria it should 

use as the basis for selection of TSLs.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Scale to 

Equipment 

Classes Not 

Analyzed
66 | Building Technologies Program eere.energy.gov

Medium-Voltage Dry-Type Equipment 

Class to Design Line Mapping

Medium-Voltage Dry-Type, Single-Phase

• Single-phase MVDT units have low unit shipments and MVA 

capacity shipped.

• Rather than directly analyzing these units, DOE scaled to these 

units by dividing the kVA rating of three-phase MVDT units by 

three.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Scale to 

Equipment 

Classes Not 

Analyzed

Three-Phase Rep Unit 

kVA

Single-Phase Scaled 

Unit kVA

300 100

1500 500

2000 667

Scales To...
67 | Building Technologies Program eere.energy.gov

Engineering Analysis:

Scaling Results

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

to other unanalyzed kVA ratings (S) within a design line 

using the 0.75 Scaling Rule:

TL1 = TL0 x (S1/ S0)

0.75

• Costs of construction and losses can be scaled when 

design parameters are held constant, including:

– frequency, magnetic flux density, current density and 

insulation level.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Model Optimized 

Designs Based 

on A’s and B’s

Design Line 7 (LVDT, 3-phase, 15 – 150 kVA): 

75 kVA Representative Unit

15

kVA

30

kVA

45

kVA

75

kVA

112.5

kVA

150

kVA

Scale Results

Scale to 

Equipment 

Classes Not 

Analyzed
68 | Building Technologies Program eere.energy.gov

Engineering Analysis:

Scaling Results

Issue 11: DOE welcomes comment on the 0.75 scaling 

rule and whether an improved scaling methodology 

exists. DOE also welcomes comment on the extent of the 

impact that the previous scaled standard levels have had 

on the low kVA units for medium-voltage dry-type or for 

any other market segments.

Choose Rep. 

Design Lines and 

Units

Select Higher 

Efficiency 

Design Options

Develop Cost 

Inputs

Develop CSLs

Scale to 

Equipment 

Classes Not 

Analyzed

Model Optimized 

Designs Based 

on A’s and B’s

• Some manufacturers indicated that the scaled results from 

the 2007 rulemaking made it difficult to manufacture 

compliant transformers for certain kVA ranges.
69 | Building Technologies Program eere.energy.gov

Markup Analysis; Energy Use & End-Use Load

National Impact Analysis

Public Meeting Agenda

1 Overview

4

2

3 Market & Tech; Screening; Engineering

6

5

Test Procedure

Life-Cycle Cost and Payback Period Analysis

7 Preliminary MIA; NOPR Analyses
70 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

Preliminary Analysis

Framework

Document

Preliminary

Analysis NOPR Final

Rule Date

Screening

Analysis

Engineering

Analysis

Energy Use and 

End-Use Load 

Characterization

Shipments

Analysis

National

Impact

Analysis

Markups for 

Equipment Price 

Determination

Life-Cycle

Cost and

Payback 

Period Analysis

Market & 

Technology 

Assessment

Preliminary 

Manufacturer 

Impact Analysis

Compliance 

Date
71 | Building Technologies Program eere.energy.gov

• Purpose

– Determine customer prices under a standards scenario based on 

manufacturer costs.

– Characterize equipment distribution channels and market 

segments.

– Describe distribution transformers‘ direct costs, expenses, and 

profits.

• Inputs

– RS Means Electrical Cost Data from 2010

• Derived contractor materials markups for dry-type transformers

• Derived installation labor and equipment markups for both liquidimmersed and dry-type transformers

– Average sales tax rates for each Census division and large state

• Output

– Baseline markups.

Markups to Determine Equipment 

Price
72 | 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.

• 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.

 Chapter 3 of the TSD contains a detailed discussion regarding the distribution channels for 

distribution transformers.

Distribution Channels

Manufacturer 

Manufacturers‘ 

Representative 

or Distributor

Utility

Manufacturer 

Manufacturers‘ 

Representative 

or Distributor

Electrical 

Contractor C&I Customer
73 | Building Technologies Program eere.energy.gov

Resulting Markup Multipliers

Liquid-Immersed Dry-Type

Distributor 1.07 Distributor 1.15

Installation Materials 1.00 Contractor Materials 1.10

Installation Labor/Equip 1.43 Contractor Labor/Equip 1.43

Sales Tax Markup 1.069 Sales Tax Markup 1.069

Overall 1.64 1.93

Issue 23: Distributor Markups. DOE estimated the distributor 

markups factors for liquid-immersed and dry-type transformers 

at 1.07 and 1.15, respectively. These factors are based on 

stakeholder comment from the previous 2007distribution 

transformers final rule. DOE welcomes comments on these 

markup factors.
74 | Building Technologies Program eere.energy.gov

• Purpose:

– Develop annual energy use parameters needed for the calculation of 

transformer operating costs

• For transformers, “energy use” refers to energy losses 

– No-load losses

• Parameterized by loss rate NL

• Occur whenever the transformer is energized

• Annual watt-hours = 8760*NL

– Load losses 

• Parameterized by loss rate LL = load loss at 100% load

• Vary with the square of the load on the transformer

• Load dependence is captured through the loss factor LSF

• LSF is proportional to the average value of the squared transformer 

load

• Annual watt-hours = 8760*LL*LSF

• The LCC must account for the existing of time-varying electricity costs

– Operating Cost = ∑ttransformer_loss(t)× electricity_cost(t)

– t is the time period index

Energy Use Determination
75 | Building Technologies Program eere.energy.gov

Liquid-immersed Transformers: 

Approach

• The utility is part of a larger system (ISO, market region, or control area)

– Use the EMM regions defined by the National Energy Modeling System (NEMS)

– Within each region there is a single system load and hourly marginal production 

price

• Hourly data compiled from FERC Form 714 filings for 2008

– Hourly form 714 loads are aggregated to produce regional system load

– Regional hourly costs are derived from system ―lambda‖ or day-ahead market 

clearing price
76 | Building Technologies Program eere.energy.gov

• The annual operating cost is equal to a sum over hours of the 

hourly losses multiplied by the hourly price

– Operating_cost = LL* ∑hours [X (hour)]2 × marginal_production_cost(hour)

• LL is defined as the loss at full load, so the equation uses the 

hourly scaled transformer load X

– X is equal to the hourly transformer load divided by the peak transformer 

load

– For this discussion, assume the peak load is equal to the transformer 

capacity 

• Simplify the calculation by noting that:

– The hourly production price is correlated with the hourly system load

– The hourly transformer load is correlated with the hourly system load 

• The loading analysis models these two correlations

Liquid-immersed Transformers: 

Approach
77 | Building Technologies Program eere.energy.gov

Liquid-immersed Transformers: 

Price-Load Correlation

• Hourly production price is correlated with the hourly system load

– Scatter plot of the hourly price (vertical axis) and hourly load (horizontal axis)

– Bin the data according to ranges of the load (stripes)

– Within each bin, price = average value + random increment

• Regional system load data define how many hours per year the load is in each bin 

0

5 0

100

150

200

250

0 20000 40000 60000 80000 100000 120000 140000 160000

Lambda $/MWh

Load MWh
78 | Building Technologies Program eere.energy.gov

• The hourly transformer load is correlated with 

the hourly system load

• Redefine this as a statistical problem

– The system load is equal to the sum of the 

loads on each transformer in the system

– What is the correlation between the aggregate 

load and any individual load?

– Express this as a joint probability distribution 

function JPDF(system_load, transformer_load)

– The joint distribution function is estimated using 

hourly load data from buildings

– Define a JPDF for residential buildings, and a 

JPDF for commercial/industrial buildings

Liquid-immersed Transformers: System 

Load – Transformer Load Correlation

1

3

5

7

9

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Individual Load Bin

Aggregate Load Bin

0.000-0.005 0.005-0.010 0.010-0.015 0.015-0.020

1

3

5

7

9

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Individual Load Bin

Aggregate Load Bin

0.000-0.005 0.005-0.010 0.010-0.015

0.015-0.020 0.020-0.025

Residential Buildings

Commercial Buildings
79 | Building Technologies Program eere.energy.gov

• Transformer owners are billed for electricity use based on a tariff

• The LCC uses a customer sample of ~5000 commercial and small-industrial 

buildings 

– Taken from the CBECS 1992 and 1995 surveys

– These buildings are used because they have monthly building-level electricity 

consumption and demand data

– These data are used to define a monthly building load factor (LF), equal to the 

average hourly load divided by the peak hourly load

• To value the transformer load losses, the LCC requires monthly values for: 

– The loss factor (LSF), equal to the average squared transformer load divided by 

the peak transformer load

– The responsibility factor (RF), equal to the squared transformer load divided by 

the peak transformer load during the hour of the building peak

• Use statistical models, derived from hourly building data, that estimate LSF 

and RF as a function of the load factor LF

Dry-Type Transformers: Approach
80 | Building Technologies Program eere.energy.gov

• The loss factor estimate is based on the rule-of-thumb

LSF = k × LF + (1-k) × LF

2 with 0 ≤ k ≤ 1

• This equation is always true for some value of k between zero and 

one

• Use data to calculate a set of values (LF, LSF, k) and estimate a 

distribution for k

Dry-Type Transformers: Loss Factor 

Calculations

0%

5%

10%

15%

20%

25%

30%

35%

40%

45%

50%

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9

parameter k

frequency

Low LF Medium LF High LF
81 | Building Technologies Program eere.energy.gov

• The monthly responsibility factor (RF) defines the contribution of 

transformer load losses to the building peak demand

• Expect the RF to be correlated to some degree with the load factor LF

– Low load factors imply temporally-variable loads and less predictable 

RF

– High load factors imply flat loads and higher, more predictable RF

• Use hourly building data to calculate a set of values (LF, RF) and 

define a distribution function that provides the probability of RF given 

a value for LF

Dry-type Transformers: 

Responsibility Factor Calculations

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1.0

0.0 0.2 0.4 0.6 0.8 1.0

Load Factor

Responsibility Factor
82 | Building Technologies Program eere.energy.gov

Customer Evaluation Rates

Issue 21: Hourly Transformer Load Data. DOE seeks 

comment on the availability of metered hourly data for 

liquid-immersed utility-owned transformers, and for drytype transformers installed in commercial or industrial 

buildings.

Issue: Dry-type Transformer Installation Practices. 

DOE seeks comment on whether dry-type transformer 

installations are associated with specific end-use loads 

such as lighting or HVAC. 
83 | Building Technologies Program eere.energy.gov

Markup Analysis; Energy Use & End-Use Load

National Impact Analysis

Public Meeting Agenda

1 Overview

4

2

3 Market & Tech; Screening; Engineering

6

5

Test Procedure

Life-Cycle Cost and Payback Period Analysis

7 Preliminary MIA; NOPR Analyses
84 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

Preliminary Analysis

Framework

Document

Preliminary

Analysis NOPR Final

Rule Date

Screening

Analysis

Engineering

Analysis

Energy Use and 

End-Use Load 

Characterization

Shipments

Analysis

National

Impact

Analysis

Markups for 

Equipment Price 

Determination

Life-Cycle

Cost and

Payback 

Period Analysis

Market & 

Technology 

Assessment

Preliminary 

Manufacturer 

Impact Analysis

Compliance 

Date
85 | Building Technologies Program eere.energy.gov

• Purpose

– To develop the customer life-cycle cost (LCC) savings and payback period (PBP) 

for higher-efficiency equipment compared to the baseline equipment.

• Method

– Use Monte Carlo simulation to estimate the life-cycle costs for a population of 

transformers (10,000 trials), implemented in an Excel® spreadsheet using 

Crystal Ball

– For each transformer, the LCC is equal to the total installed cost plus the sum of 

operating costs discounted to the base year

– For each transformer in the simulation, there is some random variation in

• The choice of design for the baseline and standard level;

• The transformer loading parameters;

• The transformer price-load correlation; and

• The transformer lifetime.

– The effect of an amended standard is to eliminate some designs from the 

available set

– This approach results in a distribution of LCC results for each candidate standard 

level.

Purpose
86 | Building Technologies Program eere.energy.gov

Transformer Design Selection

Example: Design Line 1, Candidate Standard Level 1

0

100

200

300

400

500

600

700

800

900

1000

0 50 100 150 200 250

Load Losses (watts)

No Load Losses (watts)

Design Load Losses (LL) vs No-Load Losses (NL)

at rated load

Available Designs

Selected Designs, Base

Selected Designs, Standard

Compliance

Compliant

Non-compliant
87 | Building Technologies Program eere.energy.gov

LCC and PBP Analysis

A & B 

Parameter

Transformer 

Designs

A&B 

Selection

Markups & Total 

Installed Cost

LCC Transformer 

Loading

Electricity 

Cost & Prices

Electricity 

Growth & 

Price Trends

Discount 

Rates

Compliance 

Date, 

Lifetime

Transformer 

Design 

Selection

Simulate 

Load & Price

Discount Rate 

Selection

Annual Operating 

Costs 

Operating Costs 

over the Lifetime 

of the Transformer

Net Present Value 

of Lifetime 

Operating Cost

From: 

Engineering Analysis

From: 

Energy Use and Load 

Characterization 

Analysis
88 | Building Technologies Program eere.energy.gov

• Liquid-immersed transformers

– Owners are electric utilities

– Electricity prices are hourly marginal production 

costs plus avoided capacity costs

– Use transformer-system load correlation to 

estimate transformer loads 

• Dry-type transformers

– Owners are commercial and industrial (C&I) 

buildings.

– Electricity prices are monthly marginal 

consumption and demand charges

– Use monthly loss factor and peak responsibility 

factor to estimate transformer loads

Differences in the LCC Calculations
89 | Building Technologies Program eere.energy.gov

• Some transformer owners use an estimate of the Total Ownership 

Cost (TOC) to choose a transformer design

• Their preferences are expressed through A and B values

• A is the NPV of no-load losses ($ per watt)

• B is the NPV of load losses ($ per watt)

• The percentage of owners who choose designs based on some 

valuation of the losses are called evaluators

• Three evaluation rate scenarios are defined in the LCC model

Customer Choice Model 

(1) Evaluation Rates

Design 

Lines

Evaluation Scenario

Non-evaluators Default All-evaluators

Liquid-immersed 1 — 5 0% 75% 100%

Low-voltage Dry-type 6 — 8 0% 10% 100%

Medium-capacity Dry-type 9,11 0% 50% 100%

High-capacity Dry-type 10,12,13 0% 80% 100%
90 | Building Technologies Program eere.energy.gov

• The Department uses data to 

develop estimates of A and B 

values for transformer owners

• The A and B data capture current 

market purchase decision criteria

• A = NPV of no-load losses

• B = NPV of load losses

Customer Choice Model 

(2) A and B Values

• Liquid-immersed

• Data from previous analysis, supplemented by recent utility purchase bids

• Data cluster around two values of the ratio B:A

• Dry-type 

• Derive A and B values from marginal electricity prices for commercial and industrial 

customers (ref. IEEE PC57.12.33/D8 Draft Guide for Distribution Transformer Loss 

Evaluation)

y = 0.23x + 0.00

R2 = 0.91

y = 0.45x + 0.02

R2 = 0.61

0

1

2

3

4

5

0 2 4 6 8 10 12 14

Load Losses (B) $/W ( 2010$)

No-load Losses (A) $/W (2010$)

Line 1

Line 2

Linear (Line 1)

Linear (Line 2)

Distributions of B Parameters versus A Parameters for 

Liquid-Immersed Transformers
91 | Building Technologies Program eere.energy.gov

Issues for Public Comment

Issue 24: Evaluation of Energy Efficiency in the Base 

Case. DOE seeks comment on the evaluation rates used 

in the analysis, particularly for MVDT transformers.

Issue 22: Installation Practices. DOE seeks comment on 

how to estimate the number of transformers installed in a 

building based on building characteristics such as total 

floor space, number of floors, or building activity. 
92 | Building Technologies Program eere.energy.gov

• Total Installed Costs = Manufacturer Selling Price + 

Installation Cost

• Manufacturer Selling Price = Manufacturing Costs x 

Markups

– Manufacturing cost vs. efficiency relationships developed in the 

Engineering Analysis

– Markups and Sales Taxes developed in the Markups to 

Determine Equipment Price analysis

• Installation costs represent the labor and materials 

necessary to install the appliance

– Installation costs scale with transformer weight

Markup and Installed Costs
93 | Building Technologies Program eere.energy.gov

• Hourly Marginal Electricity Production Costs

– Hourly data are compiled from FERC Form 714 filings for 2008

– For regions with functioning markets, use the day-ahead market 

clearing price

– For regions without markets, use the ―system lambda‖ data filed with 

FERC

• Regions are defined using the NEMS Electricity Market Module 

supply regions

– Within each region, use an average load-weighted sum of hourly prices 

to obtain a regional price.

– The capacity component is derived from auctions for regions with 

function capacity markets or from NEMS for all other regions.

• Develop a model of price vs. load from the FERC data

– Data are binned according to the load value

– Within each bin, price = average + random increment

Electricity Prices 

(1) Liquid-Immersed
94 | Building Technologies Program eere.energy.gov

• Transformer owners are billed for electricity based 

on a tariff

• Use a database of 90 utility tariffs

• For each building in the customer sample:

– CBECS data provide baseline electricity consumption and 

demand

– Buildings are assigned to utilities based on location (census 

division)

– The tariff is used to estimate the price paid for a marginal 

increase in electricity consumption, and the price for a marginal 

increase in electricity demand

– These prices are calculated for two seasons, summer and winter 

• Reference: Tariff-based Analysis of Commercial Building 

Electricity Prices, LBNL-55551

Electricity Prices

(2) Dry-Type
95 | Building Technologies Program eere.energy.gov

• Energy price projections to 2035 based on EIA/AEO 2010 Reference Case

• AEO High Growth and Low Growth (AEO2010) cases run as a sensitivity

• Electricity price forecasts to 2075 are developed from the average rate of 

change over the period 2020-2035

Electricity Price Forecasts

80%

85%

90%

95%

100%

105%

110%

115%

120%

2005 2010 2015 2020 2025 2030 2035

Real Price Relative to 2007

Year

Reference Case High Growth Low Growth
96 | Building Technologies Program eere.energy.gov

• Based on the cost of funds used to purchase equipment:

– Most companies use both debt and equity capital to fund investments; the 

cost of capital is the weighted average of the cost of equity and debt 

financing.

– DOE estimated the cost of equity financing using the Capital Asset Pricing 

Model (CAPM).

– Data obtained from the Damodaran Online website.

– Transformer purchasers are represented by a sample of approximately 4,500 

companies drawn from the owner categories shown in the table.

Discount Rates

Ownership Category Mean Real Discount Rate % Number of Observations

Industrial Companies 6.8 11,944

Commercial Companies 6.2 9815

Commercial Property Owners 5.5 27

Utilities, Investor-Owned 5.2 314

Utilities, Publicly Owned 3.9 7

Government Offices 3.1 26
97 | Building Technologies Program eere.energy.gov

• Average transformer lifetime is 32 years

– Reference: ORNL-6847 Determination Analysis of Energy Conservation 

Standards for Distribution Transformers

• Each transformer in the LCC simulation has a unique lifetime

• Failure rates:

– 0.5% per year from the first year of installation, due to lightning and 

other random causes

– Additional 0.5% per year due to corrosion, starting in year 15

• The failure rates are used to create a survival function, 

assuming a standard Weibull shape

Service Lifetime
98 | Building Technologies Program eere.energy.gov

Survival and Retirement Functions

Mean Lifetime: 32 years Average: 32 Years

0.0%

0.5%

1.0%

1.5%

2.0%

2.5%

3.0%

3.5%

4.0%

0 %

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

0 5 1 0 1 5 2 0 2 5 3 0 3 5 4 0 4 5 5 0 5 5 6 0

Transformer Retirement Rate (%)

Transformer Survival Rate (%)

Transformer Reliability

Transformer Retirements
99 | Building Technologies Program eere.energy.gov

Replacement and Maintenance 

Practices

Issue 25: Replacement and Maintenance Practices. DOE 

seeks comment on current transformer replacement and 

maintenance practices, and sources of data on replacement rates, 

maintenance, and repair costs.
100 | Building Technologies Program eere.energy.gov

• Results are presented for three representative design 

lines: 

– Design Line 1: Represents a rectangular-tank, single-phase, 

liquid-immersed distribution transformers, ranging from 10 kVA

to 167 kVA. The representative unit selected for design line 1 is a 

50 kVA pad-mounted transformer.

– Design Line 7: Represents three-phase, low-voltage dry-type 

distribution transformers, ranging from 15 kVA to 150 kVA. The 

representative unit selected for design line 7 is a 75 kVA

transformer.

– Design Line 12: Represents three-phase, medium-voltage 

dry-type distribution transformers, ranging from 750 kVA to 2500 

kVA. The representative unit selected for this design line is a 

1500 kVA transformer.

Results
101 | Building Technologies Program eere.energy.gov

Results 

(1) Average Total Installed Costs

0

1000

2000

3000

4000

5000

6000

7000

99.0% 99.2% 99.4% 99.6% 99.8%

Total Installed Cost ($2010)

Transformer Efficiency (%)

DL1: Liquid-immersed, 50kVA, 1 

Phase, 125kVA BIL

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

97.5% 98.0% 98.5% 99.0% 99.5%

Total Installed Cost ($2010)

Transformer Efficiency (%)

DL7: Liquid-immersed, 25kVA, 1 

Phase, 10kVA BIL

0

10000

20000

30000

40000

50000

60000

70000

80000

90000

99.0% 99.3% 99.5% 99.8%

Total Installed Cost ($2010)

Transformer Efficiency (%)

DL12: Liquid-immersed, 1500kVA, 

1 Phase, 125kVA BIL

75 3

3
102 | Building Technologies Program eere.energy.gov

Results 

(2) Average LCC Savings

In the charts above, the box represents 25 to 75% of the distribution 

of results and the whiskers represent 5 to 95% of results.

-2000

-1000

0

1000

2000

3000

4000

CSL 1 CSL 2 CSL 3 CSL 4 CSL 5 CSL 6

Average LCC Savings ($)

Efficiency Level

Design Line 1: Liquid-immersed, 50 kVA, 

1 Phase, 125 kVA BIL

Average LCC Savings

median average

-4000

-3000

-2000

-1000

0

1000

2000

3000

4000

CSL 1 CSL 2 CSL 3 CSL 4 CSL 5 CSL 6 CSL 7

Average LCC Savings ($)

Efficiency Level

Design Line 7: Dry-type, 75 kVA, 3 Phase, 

10 kVA BIL 

Average LCC Savings

median average
103 | Building Technologies Program eere.energy.gov

Results

(3) Average LCC Savings

-2000

-1000

0

1000

2000

3000

4000

CSL 1 CSL 2 CSL 3 CSL 4 CSL 5 CSL 6

Average LCC Savings ($)

Efficiency Level

Design Line 12: Dry-type, 1500 kVA, 3 Phase, 

125 kVA BIL 

Average LCC Savings

median average

In the chart above, the box represents 25 to 75% of the distribution 

of results and the whiskers represent 5 to 95% of results.
104 | Building Technologies Program eere.energy.gov

• LCC spreadsheet runs using only symmetric core designs

• Results shown for baseline efficiency and several CSL

• Distribution of LCC savings is comparable to standard 

designs; energy savings are larger

Emerging Technologies

(1) Symmetric Core

-1000

-500

0

500

1000

1500

2000

2500

3000

3500

CSL 1 CSL 2 CSL 3 CSL 4 CSL 5 CSL 6

Average LCC Savings ($)

Efficiency Level

Design Line7: Dry-type, 75 kVA, 3 phase, 

10 kVA BIL: Average LCC Savings

median average

-30000

-20000

-10000

0

10000

20000

30000

40000

CSL 1 CSL 2 CSL 3 CSL 4 CSL 5 CSL 6

Average LCC Savings ($)

Efficiency Level

Design Line 12: Dry-type, 1500 kVA, 3 phase, 

125 kVA BIL: Average LCC Savings

median average
105 | Building Technologies Program eere.energy.gov

• Installation: replace a standard unit of capacity K 

with three units of capacity K/3

• Controls are used to deactivate units when the load 

falls below certain thresholds

– Can result in a substantial decrease in no-load losses

• Replacing a single unit with three smaller, identical 

units of similar design is not cost-effective 

– This is due to the 0.75 scaling rule

– Higher relative loading on the smaller units can result 

in an increase in load-losses

• Optimal configurations can be defined given 

information on the expected distribution of loads

Emerging Technologies

(2) Core Deactivation
106 | Building Technologies Program eere.energy.gov

Markup Analysis; Energy Use & End-Use Load

National Impact Analysis

Public Meeting Agenda

1 Overview

4

2

3 Market & Tech; Screening; Engineering

6

5

Test Procedure

Life-Cycle Cost and Payback Period Analysis

7 Preliminary MIA; NOPR Analyses
107 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

Preliminary Analysis

Framework

Document

Preliminary

Analysis NOPR Final

Rule Date

Screening

Analysis

Engineering

Analysis

Energy Use and 

End-Use Load 

Characterization

Shipments

Analysis

National

Impact

Analysis

Markups for 

Equipment Price 

Determination

Life-Cycle

Cost and

Payback 

Period Analysis

Market & 

Technology 

Assessment

Preliminary 

Manufacturer 

Impact Analysis

Compliance 

Date
108 | Building Technologies Program eere.energy.gov

• Shipments Analysis

– To estimate liquid-immersed and dry-type distribution transformer 

shipments over time.

– To estimate the disaggregation of shipments into equipment classes, 

and how this changes over time.

• National Impact Analysis

– To estimate the National Energy Savings (NES) liquid-immersed and dry 

type distribution transformer efficiency standards at different levels.

• National energy savings calculated in quads for analysis period from 

2016-2045 (35 years)

– To estimate the national economic impact on the nation (or the Net 

Present Value (NPV)) from distribution transformer efficiency standards 

at different levels.

• NPV calculated in billions of dollars for products shipped over the 

analysis period from 2016-2045

Purpose
109 | Building Technologies Program eere.energy.gov

Shipments Model Inputs

Input Data Source/Description

Historical Shipments

All Distribution Transformers • HVOLT shipments data for 2001 and 2009

• BEA quantity index data 1977-2008

Market Share Data

All Distribution Transformers

• Market Share by transformer type (liquid vs.dry): Historical and Forecasted 

EIA Electricity Retail Sales data by sector type

• Market Share by kVA (capacity) rating: 2001 and 2009 HVOLT data by kVA

(capacity) rating

Replacements

Distribution Transformer Lifetime • From Life-Cycle Cost Analysis

Base Case Forecasted Shipments

Liquid-Immersed Transformers • Same growth rate as EIA forecast of Electricity Retail Sales to all sectors

Dry-Type Transformers • Same growth rate as EIA Forecast of Electricity Retail Sales to commercial 

and industrial sectors

New Capacity Shipments

All Distribution Transformers • Deduced from forecasted base case shipments and replacements

Standards Case Forecasted Shipments: Long-Term Purchase Elasticity

Liquid-Immersed Transformers • Price sensitivity based on transformer capacity-to-peak ratio

Dry-Type Transformers • Price sensitivity based on sales and price data for Commercial Unitary AirConditioners
110 | Building Technologies Program eere.energy.gov

• Utilized historical and forecasted EIA Electricity Retail 

Sales data by sector type to estimate market share by 

transformer type (liquid vs. dry)

• Utilized HVOLT market share data by kVA (capacity) 

rating for 2001 and 2009; forecasted kVA market shares 

set equal to 2009 values

Equipment Class Market Shares

Issue 26: Forecasted Market Shares of Liquid-Immersed and DryType Distribution Transformers. This model was based on the shipments 

data for the years 2001 and 2009, as well as forecasted electricity sales 

with the assumption that transformer capacity market shares follow the 

relative electricity consumption of the end users. For each of the he market 

shares for different kVA ratings and equipment classes, DOE assumed that 

the relative market share within each transformer type. DOE seeks 

comment on its approach.
111 | Building Technologies Program eere.energy.gov

• Utilized BEA‘s Quantity Index data in combination with the 2001 and 

2009 HVOLT historical shipments data to estimate historical 

shipments.

• Constructed base case forecast by estimating that shipments are 

driven by long-term growth in electricity consumption (sales).

Base Case Shipments Forecast

-

20,000 

40,000 

60,000 

80,000 

100,000 

120,000 

140,000 

1950 1970 1990 2010 2030 2050

Shipments (MVA)

Shipments Estimate, All Transformers Historical Shipments, All Transfomers

Shipments Estimate, Liquid-Immersed Transformers Shipments Estimate, Dry-Type Transformers
112 | Building Technologies Program eere.energy.gov

• Impacts to Standards Case shipments forecasts due to 

purchase price and operating cost changes

• Liquid-immersed Transformers

– Predicted variability in observed transformer capacity-to-peak ratio 

as a function of variability in transformer price

• Capacity-to-peak ratio data from historical FERC Form 1 data (1994-

2001)

– Obtained a value of -0.04 for price elasticity

• Consumers purchase transformers with relatively high capacity-to-peak 

ratios, implying less sensitivity to purchase price

• For Dry-Type Transformers

– Historical purchase data not available

– Because transformers are primarily used in commercial and 

industrial applications, DOE used sales and price data for 

commercial unitary air conditioners as a proxy to estimate price 

elasticity.

– Obtained a value of -0.02 for price elasticity

Purchase Price and Operating Cost 

Impacts
113 | Building Technologies Program eere.energy.gov

• Very small impact to standards case shipments forecast for all 

CSLs

Standards Case Shipments Results

54,000

57,000

60,000

63,000

66,000

69,000

72,000

75,000

2009201120132015201720192021202320252027202920312033203520372039204120432045

MVA/year

Liquid-Immersed Transformers

Base CSL1 CSL2 CSL3

CSL4 CSL5 CSL6 CSL7

22,000 

23,000 

24,000 

25,000 

26,000 

27,000 

28,000 

29,000 

30,000 

31,000 

32,000 

33,000 

2009201120132015201720192021202320252027202920312033203520372039204120432045

MVA/year

Dry-Type Transformers

Base CSL1 CSL2 CSL3

CSL4 CSL5 CSL6 CSL7
114 | Building Technologies Program eere.energy.gov

• The shipments model provides annual age distribution of 

transformers for past, present, and future years

• Accounting for replacements allows estimate of age 

distribution of installed transformers

Affected Stock
115 | Building Technologies Program eere.energy.gov

Age Distribution of Liquid-Immersed 

Transformer Stock: Four Selected Years

0 

10000 

20000 

30000 

40000 

50000 

60000 

70000 

80000 

90000 

0 10 20 30 40 50 60

Capacity (MVA)

Transformer Vintage (years)

Affected Stock: 0%

2010

0 

10000 

20000 

30000 

40000 

50000 

60000 

70000 

80000 

90000 

0 10 20 30 40 50 60

Capacity (MVA)

Transformer Vintage (years)

Affected Stock: 8%

2018

0 

10000 

20000 

30000 

40000 

50000 

60000 

70000 

80000 

90000 

0 10 20 30 40 50 60

Capacity (MVA)

Transformer Vintage (years)

Affected Stock: 58%

2035

0 

10000 

20000 

30000 

40000 

50000 

60000 

70000 

80000 

90000 

0 10 20 30 40 50 60

Capacity (MVA)

Transformer Vintage (years)

Affected Stock: 84%

2045
116 | Building Technologies Program eere.energy.gov

• Total Customer Cost

– Average values for individual design lines 

(for a specific kVA) as a function of 

efficiency level taken from LCC analysis

• Repair and Maintenance Costs

– No increase in repair and maintenance 

costs with efficiency

• Annual Load and No-Load Losses

– Average values for individual design lines 

(for a specific kVA) as a function of 

efficiency level taken from LCC analysis

• Customer Evaluation Rates

– Inputs from LCC analysis (total customer 

cost, load and no-load losses, peak 

responsibility factor, RMS loading) account 

for customer evaluation rates

• Peak Responsibility factor and Initial Peak 

Loading

– Average values taken for individual design 

lines from LCC analysis

• RMS Loading

– Average values taken for individual design 

lines from LCC analysis

• Marginal Energy and Demand Prices

– Average prices taken from LCC analysis

– Future energy prices adjusted according to 

trend forecasted from the 2010 Annual 

Energy Outlook

• Electricity Site-to-Source Conversion Factors

– Conversion factors based on heat rates 

from NEMS corresponding to 2010 Annual 

Energy Outlook

– Average Heat Rate (Btu/kWh) for Base 

Load, and Average Gas Heat Rate 

(Btu/kWh) for Peak Load

• Discount Rate

– 7% and 3% real from OMB‘s Regulatory 

Analysis Guideline A-4

• Present Year

– Future expenses are discounted to the year 

2010

National Impacts Analysis Inputs
117 | Building Technologies Program eere.energy.gov

• Site Energy Savings and Cost Impacts from 13 Design Lines 

scaled to account for 115 kVA Capacity Class Ratings

– LCC Analysis addresses 13 Design Lines with a  ̳representative 

unit‘ selected for each Design Line based on highest sales 

volume

– National Impact Analysis needs to address 115 different kVA

ratings

– Need to convert site energy savings and cost impacts from 

 ̳representative unit‘ to values representing all 115 kVA ratings

– 0.75 Scaling Rule used to perform conversion

Site Energy Savings and Cost 

Impacts
118 | Building Technologies Program eere.energy.gov

• Used distribution of A and B values to capture the variability seen in the 

market, i.e., not all transformer purchases have identical costs of losses.

• Some transformer purchasers place no value on those losses while 

others place significant value. Those that do are said to be Evaluators.

• Distinct evaluation percentages applied to liquid-immersed and dry-type.

• Average input values from LCC analysis (purchase cost, NLL, LL, PRF, 

RMS loading) incorporate the evaluation rates used in the LCC analysis; 

no further adjustments needed for National Impact Analysis.

Customer Evaluation Rates

Design 

Lines

Evaluation Scenario

Non-evaluators Default All-evaluators

Liquid-immersed 1 — 5 0% 75% 100%

Low-voltage Dry-type 6 — 8 0% 10% 100%

Medium-capacity Dry-type 9,11 0% 50% 100%

High-capacity Dry-type 10,12,13 0% 80% 100%
119 | Building Technologies Program eere.energy.gov

Customer Evaluation Rates

Issue 27: Customer Evaluation Rate Forecasts. To 

accurately estimate the share of consumers that would be 

affected by a standard at a particular efficiency level, DOE‘s LCC 

and PBP analyses considered the percentage of the consumers 

that evaluate their purchase in the base and standards cases. 

DOE invites comment on whether the number of purchasers who 

evaluate, or the evaluation criteria they use, are likely to change 

in the future.
120 | Building Technologies Program eere.energy.gov

Example Annual Savings and Cost 

Results

-$2.0

-$1.0

$0.0

$1.0

$2.0

$3.0

2016 2026 2036 2046 2056 2066 2076 2086 2096

Billions of 2010 Dollars

Liquid-Immersed - CSL3 

-$0.4

-$0.2

$0.0

$0.2

$0.4

$0.6

$0.8

$1.0

2016 2026 2036 2046 2056 2066 2076 2086 2096

Billions of 2010 Dollars

Dry-Type - CSL3 

-$2.0

-$1.0

$0.0

$1.0

$2.0

$3.0

$4.0

2016 2026 2036 2046 2056 2066 2076 2086 2096

Billions of 2010 Dollars

All Transformers - CSL3 

Operating Cost Savings Equipment Cost Net Savings
121 | Building Technologies Program eere.energy.gov

• Summary of Cumulative National Energy Savings (2016–

2045) and Net Present Value (2016–2104) Impact

Summary of Cumulative National 

Energy Savings Impact
122 | Building Technologies Program eere.energy.gov

Markup Analysis; Energy Use & End-Use Load

National Impact Analysis

Public Meeting Agenda

1 Overview

4

2

3 Market & Tech; Screening; Engineering

6

5

Test Procedure

Life-Cycle Cost and Payback Period Analysis

7 Preliminary MIA; NOPR Analyses
123 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

Preliminary Analysis

Framework

Document

Preliminary

Analysis NOPR Final

Rule Date

Screening

Analysis

Engineering

Analysis

Energy Use and 

End-Use Load 

Characterization

Shipments

Analysis

National

Impact

Analysis

Markups for 

Equipment Price 

Determination

Life-Cycle

Cost and

Payback 

Period Analysis

Market & 

Technology 

Assessment

Preliminary 

Manufacturer 

Impact Analysis

Compliance 

Date
124 | Building Technologies Program eere.energy.gov

Manufacturer Impact Analysis

Overview

Purpose

• To identify the impacts of amended energy conservation standards on 

manufacturers.

• Key output of MIA is the change in industry net present value (INPV)

due to amended standards.

• The MIA consists of three phases:

Industry 

profile

Develop 

straw-man 

GRIM*

Develop 

interview 

guide

Interviews

& 

industrywide / 

subgroup

analyses

Assess direct 

employment, 

competition, 

cumulative 

burden

Phase 1 Phase 2 Phase 3
125 | Building Technologies Program eere.energy.gov

Manufacturer Impact Analysis

Overview

Phase 1

• DOE creates an industry profile to characterize the industry and identify 

important issues that require consideration.

Phase 2

• DOE prepares an industry cash-flow model and an interview questionnaire to 

guide subsequent discussions.

Phase 3

• DOE interviews manufacturers and assesses the impacts of amended 

standards both quantitatively (using the Government Regulatory Impact Model) 

and qualitatively (impacts on competition, manufacturing capacity, employment, 

and regulatory burden).

Industry 

profile

Develop 

straw-man 

GRIM*

Develop 

interview 

guide

Interviews

& 

industrywide / 

subgroup

analyses

Assess direct 

employment, 

competition, 

cumulative 

burden

Phase 1 Phase 2 Phase 3
126 | Building Technologies Program eere.energy.gov

Preliminary Manufacturer Impact 

Analysis – Key Issues

• Core Steel Availability

– Limited global supply for higher efficiency core steels.

– Only a few global suppliers of M2 steel, and only one supplier of amorphous 

ribbon.

• Equipment Conversion Costs

– Certain technology options require large capital investments, retooling, and 

stranded assets.

– Switching from butt-lap to miter, investing in symmetric core technology, 

or increased amorphous core production

• Intellectual Property

– Many symmetric core designs are patented.

– Core deactivation technology is patented.
127 | Building Technologies Program eere.energy.gov

Preliminary Manufacturer Impact 

Analysis – Key Issues (Continued)

Issue 18: DOE requests comment on its identification of key 

issues in its preliminary manufacturer impact analysis and 

requests data to assist evaluating the potential impact of 

amended standards on manufacturers.

Issue 19: DOE welcomes comment on the supply of core 

steels used in its designs. In particular, DOE seeks comment 

on the global supply of grain-oriented silicon steel, such as 

M3 and M2, and amorphous core steels compared to the 

projected consumption based on CSLs.
128 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

NOPR

Framework

Document

Preliminary

Analysis NOPR Final

Rule Date

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

National

Impact

Analysis

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date
129 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

NOPR

Framework

Document

Preliminary

Analysis NOPR Final

Rule Date

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

National

Impact

Analysis

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date
130 | Building Technologies Program eere.energy.gov

Revised Preliminary Analysis

Analysis Action

Engineering Analysis

• Consider comments

• Revise using latest data

Life-Cycle Cost and 

Payback Period Analyses

• Consider comments

• Revise using latest data

• Conduct LCC sub-group analysis

National Impacts Analysis

• Consider comments

• Revise using latest data
131 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

NOPR

Framework

Document

Preliminary

Analysis NOPR Final

Rule Date

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

National

Impact

Analysis

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date
132 | Building Technologies Program eere.energy.gov

• Purpose

– Evaluate impacts on any identifiable groups or customers who may be 

disproportionately affected by any amended national energy efficiency 

standard level.

• Method

– Analyze the LCC and payback periods (PBPs) for those customers that 

fall into any identifiable groups. LCC spreadsheet model allows for 

different inputs to represent particular groups.

• Output

– Customer subgroup life-cycle costs and payback periods.

– Identification of subgroups particularly affected by an amended 

standard.

Life-Cycle Cost Subgroup Analysis
133 | Building Technologies Program eere.energy.gov

DOE will evaluate the LCC impacts on the subgroups 

identified in the 2007 distribution transformers final rule.

• Municipal Utilities

– Use transformers that tend to serve more diverse, urban loads than 

transformers that serve more rural areas. The increased load diversity increases 

the load factor and the transformer loading, thus increasing the potential 

savings from reduced load losses.

• Rural Electric Cooperatives

– Use transformers that tend to serve smaller loads than transformers that serve 

urban areas. The lower loading decreases the potential savings from reduced 

load losses and, thus, the benefits from efficiency improvements. 

• Vault Installed Transformers

– Distribution transformers at higher efficiency levels have larger volumes and 

higher installation costs, due to required modifications to enlarge the vaults that 

house them. This can dramatically decrease the economic benefits from the 

highest standard levels.

Proposed Subgroups
134 | Building Technologies Program eere.energy.gov

• DOE will be especially sensitive to increases in the 

purchase price of the equipment due to amended 

standards, to avoid negative impacts on identifiable 

population groups that may not be able to afford 

significant increases in equipment price.

Purchase Price Impacts
135 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

NOPR

Framework

Document

Preliminary

Analysis NOPR Final

Rule Date

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

National

Impact

Analysis

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date
136 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

NOPR

Framework

Document

Preliminary

Analysis NOPR Final

Rule Date

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

National

Impact

Analysis

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date
137 | Building Technologies Program eere.energy.gov

• Purpose

– To investigate the effects on electric utilities from reduced 

energy consumption and reduced peak load demand due to 

amended energy conservation standards.

• Method 

– Uses national energy savings results.

– Uses the Energy Information Administration‘s National Energy 

Modeling System (NEMS) tailored for DOE‘s Building 

Technologies Program (NEMS-BT).

• Output

– Change in electricity sales and price by region.

– Change in the mix of electricity generation.

– Change in new capacity construction.

Utility Impact Analysis
138 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

NOPR

Framework

Document

Preliminary

Analysis NOPR Final

Rule Date

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

National

Impact

Analysis

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date
139 | Building Technologies Program eere.energy.gov

Employment Impact Analysis

• Purpose

– To report net jobs created or eliminated nationally as a 

consequence of amended energy conservation standards.

• Method 

– Uses the ImSET (Impact of Sector Energy Technologies) 

model for the evaluation of indirect employment impacts.

– Changes in equipment and energy expenditures are 

developed in the National Energy Savings Analysis.

– Direct employment impacts are developed in the Manufacturer 

Impact Analysis.

• Output

– Change in commercial and energy sector employment as a 

consequence of amended energy conservation standards
140 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

NOPR

Framework

Document

Preliminary

Analysis NOPR Final

Rule Date

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

National

Impact

Analysis

Revise 

Preliminary 

Analysis

Engineering

Analysis

Compliance 

Date
141 | Building Technologies Program eere.energy.gov

• Purpose

– Report environmental impacts resulting from amended energy 

conservation standards, including changes in power plant emissions

• Method 

– Energy savings results taken from the National Energy Savings 

Analysis.

– Energy Information Administration‘s National Energy Modeling 

System (NEMS-BT) provides power-plant emissions.

• Output

– Estimate of national emission reductions of CO2, NOx, and 

mercury.

• Carbon dioxide (CO2) will be the primary emissions reported.

• Mercury (Hg) emissions will also be reported.

• Nitrogen Oxide (NOx) emissions will be reported for the 22 states 

where emissions are not capped.

• Discuss national emissions reductions of Sulfur Dioxide (SO2); 

existing legislation cap SO2, so physical emission reductions will be 

zero or nearly zero.

Environmental Assessment
142 | Building Technologies Program eere.energy.gov

• DOE intends to use the most current Social Cost of Carbon 

(SCC) values developed by interagency reviews.

– SCC is intended to be a monetary measure of the incremental damage 

resulting from greenhouse gas (GHG) emissions, including but not 

limited to agricultural productivity loss, human health effects, property 

damage from rising sea level, and changes in the ecosystem.

• At present, the most recent interagency estimates of the 

potential global benefits resulting from reduced CO2 emissions 

in 2010 are $4.90, $22.10, $36.30, and $67.10 per metric ton in 

2009 dollars.

– For emission reductions that occur in later years, these values grow in 

real terms over time.

• DOE will also estimate the potential monetary benefit of 

reduced NOx emissions resulting from the considered standard 

levels.

Environmental Assessment

Monetization of Emission Reductions
143 | Building Technologies Program eere.energy.gov

Environmental Assessment

Issue 20: Valuing Air-Borne Emission Reductions. DOE 

acknowledges that there may be certain benefits resulting 

from the improved efficiency of Distribution Transformers that 

are not captured directly by the equipment ̳s users. These 

include both environmental and energy security-related 

externalities that are not reflected in energy prices, such as 

reduced emissions of greenhouse gases and reduced use of 

fossil fuels for electricity generation. DOE invites comments 

on the nature and magnitude of such benefits. DOE also 

invites comment on possible approaches to monetizing the 

emission reductions expected to result from energy 

conservation standards
144 | Building Technologies Program eere.energy.gov

Steps in the Standards Rulemaking: 

NOPR

Framework

Document

Preliminary

Analysis NOPR Final

Rule

Compliance 

Date

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

National

Impact

Analysis

Revise 

Preliminary 

Analysis

Engineering

Analysis
145 | Building Technologies Program eere.energy.gov

• Purpose

– To investigate the national impacts due of non-regulatory alternatives 

compared with mandatory amended energy conservation standards.

– The non-regulatory alternatives that may be considered include: 

• No new regulatory action; early replacement; prescriptive standards; 

customer tax credits; manufacturer tax credits; customer rebates; 

voluntary efficiency targets and bulk government procurement.

• Method

– NES spreadsheet model is modified to consider scenarios. These 

include: energy prices and escalation factors; implicit market discount 

rates; customer purchase price, operating cost, and income elasticities; 

and equipment stock data. 

• Output

– National Energy Savings and Net Present Value of the non-regulatory 

alternatives.

– Impact of non-regulatory alternatives on purchase price and use of 

energy-efficient equipment.

Regulatory Impact Analysis
146 | 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 18, 2011

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