June 29, 2012
VIA EMAIL TO: DistributionTransformers-2010-STD-0048@ee.doe.gov
Ms. Brenda Edwards
U.S. Department of Energy
Buildings Technologies Program
Mail Stop EE-2J
1000 Independence Avenue SW
Washington, DC 20585-0121
NEMA Comments on DOE Energy Conservation Program: Supplemental Post-Notice of
Proposed Rulemaking Analysis for Distribution Transformers
Docket Number EERE-2010-BT-STD-0048
RIN 1904-AC04
Dear Ms. Edwards,
The National Electrical Manufacturers Association (NEMA) thanks you for the opportunity to
provide comments on the Department of Energy’s Supplemental Post-Notice of Proposed
Rulemaking Analysis for Distribution Transformers.
As you may know, NEMA is the trade association of choice for the electrical manufacturing
industry. Founded in 1926 and headquartered near Washington, D.C., its approximately 450
member companies manufacture products used in the generation, transmission and
distribution, control and end-use of electricity. These comments are submitted on behalf of
NEMA Distribution Transformer manufacturers.
Please find our detailed comments below. If you have any questions on these comments,
please contact Alex Boesenberg of NEMA at 703-841-3268 or alex.boesenberg@nema.org.
Sincerely,
Kyle Pitsor
Vice President, Government Relations
NEMA Comments on DOE Energy Conservation Program: Supplemental Post-Notice of
Proposed Rulemaking Analysis for Distribution Transformers
NEMA thanks the Department of Energy and its staff for providing NEMA and other
stakeholders the opportunity to participate in the innovative negotiated rulemaking process
for energy conservation standards for distribution transformers. From NEMA’s perspective,
this process was extremely valuable in helping all the stakeholders understand the interests
and concerns of the other stakeholders. In addition, it provided an opportunity for the
transformer and steel manufacturers to explain existing technologies and markets; and for the
Department’s consultants to refine the various models and input assumptions used in the
analysis.
NEMA and its members are committed to distribution transformer energy efficiency standards
that are economically justifiable. Through NEMA, the industry developed the first specification
for transformer energy efficiency, NEMA TP1-1996. In addition, we developed a voluntary
NEMA Premium ® Efficiency Transformer program to promote efficiencies even higher than
the national standard. During the negotiated rulemaking process, we advocated proposals to
increase distribution transformer efficiency above the current federal minimums, which are
already quite high, ranging from 97 percent to 99.49 percent.
We share with other stakeholders the objective of increasing energy efficiency, but we must
balance that objective with the critical needs of ensuring a competitive transformer
manufacturing base in the U.S. and maintaining U.S. jobs, both of which are important criteria
that the Energy Policy and Conservation Act requires the Department to incorporate in
developing a Final Rule.
From NEMA’s perspective, the energy efficiency levels proposed in Table 1.2 (Proposed
Energy Conservation Standards for Low-Voltage, Dry-Type Distribution Transformers) and
Table 1.3 (Proposed Energy Conservation Standards for Medium-Voltage, Dry-Type
Distribution Transformers) of the February 10, 2012 Notice of Proposed Rulemaking
represent the highest level of energy savings that maintain a healthy transformer industry in
the United States. Going beyond the proposed levels will disrupt the steel and transformer
industries in the U.S. Further, we are concerned that transformer efficiency levels higher than
what are proposed in the NOPR will lead some utilities to rebuild old transformers in place of
buying new, high efficiency transformers, which would be counter-productive to the objective
of greater energy savings.
Throughout the entire negotiated rulemaking process, NEMA has consistently maintained the
following three principles in our analysis and recommendations:
1. NEMA supports developing new transformer energy efficiency standards, provided
that those standards are justified from a cost effectiveness perspective.
2. NEMA believes it is important to support and maintain a healthy transformer industry in
the U.S., and does not support efficiency regulations that would lead to less
competitive markets and conditions for both inputs and transformers.
3. NEMA believes it is important that all stakeholders understand the potential negative
impacts on small manufacturing facilities, if significantly higher efficiency standards are
adopted.
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NEMA has used these three principles, together with the analysis performed by Navigant
Consulting and Lawrence Berkeley National Laboratory (LBNL), to develop our
recommendations to the other stakeholders during the negotiated rulemaking. The NEMArecommended efficiency levels are closely aligned with the energy efficiency levels proposed
in the February 10th NOPR. NEMA strongly recommends that the DOE adopt the efficiency
levels stated in the NOPR because we believe these are the highest efficiency levels that
support healthy utility, steel and transformer industries in the United States.
NEMA would like to remind the DOE and the other participants of the general and detailed
comments included in our letter to DOE on April 10, 2012 concerning Docket Number: EERE2010-BT-STD-0048. These comments are part of the official record.
NEMA Comments on Additional DOE Analysis on Liquid-Immersed Transformers
Presented in Appendix 1-A (Summary of Supplemental Post-Notice of Proposed
Rulemaking Analysis for Distribution Transformers) and Appendix 8-A (Additional Trial
Standard Level to the Supplemental Post-Notice of Proposed Rulemaking Analysis for
Distribution Transformers). (This additional analysis covers pole and pad mounted
transformers, network and vault transformers and high BIL transformers.)
1. NEMA’s primary concern is that any energy efficiency levels selected by the DOE
should provide for a good balance of manufacturing using conventional steels such as
M-3 and newer transformer designs using amorphous materials. This issue is
important not only to the transformer manufacturing industry, but also the utility
industry (i.e. users), the U.S. steel industry as well as the ratepayers and the economy
overall. It should be noted that several of the attendees at the June 20th public meeting
stressed to need to have an open and balanced market between M-3 and amorphous
materials.
2. NEMA still has a lot of questions about the analysis and the assumptions used in the
analysis. We understand the concerns of EEI and others about the electricity prices in
the analysis being overstated (perhaps by a factor of two) and the transformer costs
being understated. This combination produces projected paybacks and lifecycle costs
that appear significantly more attractive than reality.
3. In addition, some of the trends in the tables indicate either an error in the data or an
unrealistic event occurring when the analysis begins to pick amorphous over
conventional steel. The manufacturers have consistently reported that transformer
costs gradually increase as the required efficiency increases. However, some of the
data in the tables do not reflect this natural trend. For example, in Table 1-A.5.2, the
mean retail cost drops in going from EL1 to EL1.5 and then remains identical for EL2
and EL3. In addition, in Table 1-A.5.5, the Efficiency (%) for EL 0.5 is higher than the
efficiency for EL1. Also, in Table 1-A.5.10, the mean retail cost for EL1.5 is
significantly less than the mean retail cost for EL1.
4. NEMA recommends that the efficiency levels for vaults, network and other
submersible distribution transformers be kept at EL0 because of the size and weight
limitations on the replacement transformers.
5. NEMA recommends that the efficiency level for medium voltage liquid filled
transformers with BIL (Basic Impulse Level) greater than or equal to 150kV and multivoltage (defined later in NEMA Responses Item 1.d) transformers be maintained at the
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existing EL0 because of the design difficulties and significantly higher costs associated
with these transformers.
6. The issue of the efficiency level of pads vs. poles is a complicated issue. On one hand,
it makes sense to retain EL0 for poles because the replacement pole transformers are
often constrained by weight and height limitations and increase the efficiency level for
pads to 1.0. On the other hand, having both types of transformers at the same EL
allows the manufacturers to use the same design for both applications and minimizes
the chance of gamesmanship in converting new distribution installations to poles in
order to avoid the higher efficiency level and costs associated with the same size pad
transformer.
In light of the above comments, NEMA believes that the Trial Standard Level A presented in
Table 1-A.4.2 (and Table 8-B.1.2) is the only TSL in the Supplemental Analysis that meets (or
comes close to meeting) the three principles that NEMA has consistently applied during the
rulemaking process. However, NEMA recommends EL0 for Design Line 2 because the earlier
analysis indicated that the cross-over point between M-3 and amorphous was about EL0.25.
Moving to EL0.5 in TSL-A will create a bias in favor of amorphous that goes against the
consensus of the participants. In addition, NEMA believes that Trial Standard Levels B-D are
inappropriate because the Supplementary Analysis provided by James Raba and DOE’s
consultants on June 20, 2012 indicate that:
 Although TSL-B allows for some competition of M-3 and amorphous (SA1) at DL1, the
construction of the other DLs require M-2, ZDMH and SA1 to meet the efficiency
levels. Both the steel and transformers manufacturers have indicated that there is
not enough supply of these materials to meet projected market demands.
 For TSL-C and TSL-D, the DOE analysis indicates that all of the DLs will require from
79% to 100% SA1 to remain cost-effective. This shift to amorphous is completely
counter to the goal of maintaining a healthy steel industry in the United States.
NEMA RESPONSES TO DOE’s “REQUEST FOR COMMENT”
1. DOE requests comment on the new equipment class definitions.
NEMA requests that the DOE’s definitions of Pad Mounted, and Network and Vault
transformers on page 1-A-4 of the Supplemental Analysis document be adjusted as
follows (new text underlined):
a. “Pad-mounted” or “Substation” transformersf are designed for mounting on
(e.g.) concrete pad that offers a flat surface. Though they may have added
levels of protection to prevent tampering or electrical shock, pad-mounted and
substation transformers have fewer of the size and weight concerns that polemounted transformers experience.
b. “Networkg”, “Vault” or “Submersible” transformers are designed for use in
subways, vaults or otherwise size-restricted locations; and are suitable for
occasional or continuous submerged operation. Transformer nameplate shall
clearly indicate for either “Network”, “CST”, “Subsurface”, “Subway”, or “Vault”
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application. This transformer application requires that they be built to a much
higher level of ruggedness and durability. Furthermore, compactness is of
utmost importance because their location is frequently in dense urban
environments where expanding a vault or size-restriction to accommodate a
larger, more-efficient unit could be done only at great cost that would far
outweigh any savings in operating cost.
c. To footnote “f” add the following concerning additional IEEE references:
“C57.12.36 or C57.12.10”. These references supply necessary information
regarding substation transformers, added as a result of NEMA comment 1a)
above.
d. Add to page 1-A-4 the following new definition and explanation, regarding multivoltage transformers: “Multi-Voltage Transformer” refers to a distribution
transformer that has more than one and not more than three nominal input
voltages (the high-voltage or primary voltage in the case of a step-down
transformer), all of which are identified in the apparent power or “kVA” section
of the transformer nameplate (e.g. 7200 X 14400 or 7200 X 7970 X 14400).
The term Multi-Voltage Transformer does not apply to transformers with
multiple (i.e. series/parallel) output voltages (low-voltage or secondary voltage
in the case of a step-down transformer).
Multi-Voltage Transformers allow users who operate multiple distribution
systems with different nominal voltages to streamline their inventory and are
also often used in cases where the nominal system voltage is planned to be
upgraded or changed in the near future and the user does not want to replace a
recently installed transformer simply to accommodate the new nominal system
voltage. “Tap Voltages”, on the other hand, which typically deviate from the
nominal input voltage by 10% or less and are identified on the nameplate as
such, are intended to enable voltage regulation of the output. Tap Voltages are
not considered “nominal voltages”.
e. NEMA recommends that the definitions i and ii on page 1-A-9 be modified, to
add “and/or” after each line. These requirements are currently worded so as to
be inclusive, and should be more flexible. This can be accomplished by adding
the “or” option.
2. DOE requests data on distribution transformer shipments for each of the presented
equipment classes by kVA rating, similar to the data presented in Table 9.3.2 of the
NOPR TSD, presented here for reference.
NEMA does not have this detailed information available and recommends the DOE
contact manufacturers directly.
3. DOE requests comment on the appropriate efficiency levels for network/vault and
≥200 kV BIL equipment classes.
NEMA recommends EL0 for network and vault transformers because of the size and
weight restrictions noted in NEMA’s April 10, 2012 letter to DOE. In addition, NEMA
recommends EL0 for high BIL transformers. The BIL rating of a transformer has a
significant impact on the losses of the product because the clearance between the
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windings and the core must increase as the BIL increases. This results in a greater
volume of core materials and thus a greater amount of no-load losses, which
significantly reduce the ability to increase the transformer’s efficiency. NEMA defines
high BIL transformers as any liquid-immersed distribution transformer that has a line to
ground or line to neutral voltage of 19000 volts or above and is rated 150 kV BIL or
above. This would include such voltages as 34500GrdY/19920 V, 19920/34500Y V,
19050/33000Y V, 34500 V, etc.
In addition, NEMA recommends including multi-voltage transformers as defined in item
d. above in the equipment class of transformers that remain at EL0. Multi-voltage
transformers require additional insulation just like high kV BIL transformers. This drives
a lower space factor which makes it more difficult to reach higher efficiencies. For
instance, for a 7200 X 14400 volt multi-voltage unit, the entire coil would be insulated
to 125kV as opposed to 95kV if it were only 7200 volts.
NEMA also proposes the below indicated changes to table 1A.4.2.
a. A new class 1C should be created to separate single-phase Network/Vault
transformers from other single-phase products.
b. Under TSL A for category 1B the efficiency level should be EL0. This is
because making pole transformers at higher efficiencies than EL0 will increase
core cost and overall weight, which will eventually require the poles to be
replaced to accommodate the heavier transformers. This will skew the analysis
regarding market share for both pole and pad mounted products, and invalidate
DOE projections. Retaining EL0 for DL2 reinforces the analysis presented in the
original February 2012 NOPR.
c. Under TSL A, add a new type 1D for single phase products and change the
existing type 2D should be >= 150 kV BIL, vs. 200 kV BIL. The small number of
200kV BIL products made today makes a >200 kV BIL equipment class a
useless category. Making equipment classes 1D and 2D type >= 150 kV BIL is
a more realistic categorization of these products and produces a more
noticeable effect and is consistent with previous NEMA positions on the subject.
Revised Table 1-A.4.2
EC
DL
Phases
1A
1B
1B
1C
1D
1
2
3
-
1
1
1
1
1
2A
2A
2B
2C
2D
4
5
-
3
3
3
3
3
Notice of Public Meeting Trial Standard Levels for Liquid-immersed
Distribution Transformers
Type
Trial Standard Levels by Efficiency Level
A
B
C
Pad
EL 1
EL 1.5
EL 2
Pole
EL 0
EL 0.5
EL 2
Pole
EL 1
EL 1
EL 2
Network/Vault
EL 0
EL 0
EL 0
>=150kV BIL and/or
EL 0
EL 0
EL 0
Multi-Voltage
Pad
EL 1
EL 1.5
EL 2
Pad
EL 1
EL 1.5
EL 2
Pole
Scaled
Scaled
Scaled
Network/Vault
EL 0
EL 0
EL 0
>=150kV BIL and/or
EL 0
EL 0
EL 0
Multi-Voltage
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4. DOE request from utilities pole replacement costs by transformer capacity.
NEMA does not have data on this subject and recommends the DOE contact the
utilities directly to obtain this data.
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