[Federal Register Volume 86, Number 134 (Friday, July 16, 2021)]
[Proposed Rules]
[Pages 37687-37708]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2021-14902]


========================================================================
Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

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Federal Register / Vol. 86, No. 134 / Friday, July 16, 2021 / 
Proposed Rules

[[Page 37687]]



DEPARTMENT OF ENERGY

10 CFR Part 430

[EERE-2017-BT-STD-0009]
RIN 1904-AD79


Energy Conservation Program: Energy Conservation Standards for 
Certain Commercial and Industrial Equipment; Early Assessment Review; 
Walk-In Coolers and Freezers

AGENCY: Office of Energy Efficiency and Renewable Energy, Department of 
Energy.

ACTION: Request for information.

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SUMMARY: The U.S. Department of Energy (``DOE'') is undertaking an 
early assessment review to evaluate whether to amend the energy 
conservation standards for walk-in coolers and freezers (``walk-ins'' 
or ``WICFs''). Specifically, through this request for information 
(``RFI''), DOE seeks data and information to evaluate whether amended 
energy conservation standards would result in significant savings of 
energy; be technologically feasible; and be economically justified. DOE 
welcomes written comments from the public on any subject within the 
scope of this document (including those topics not specifically raised 
in this RFI), as well as the submission of data and other relevant 
information concerning this early assessment review.

DATES: Written comments and information are requested and will be 
accepted on or before August 16, 2021.

ADDRESSES: Interested persons are encouraged to submit comments using 
the Federal eRulemaking Portal at www.regulations.gov. Follow the 
instructions for submitting comments. Alternatively, interested persons 
may submit comments, identified by docket number EERE-2017-BT-STD-0009, 
by any of the following methods:
    1. Federal eRulemaking Portal: www.regulations.gov. Follow the 
instructions for submitting comments.
    2. Email: to <a href="/cdn-cgi/l/email-protection#074677776b6e6669646254736669636675637456726274736e6869744762622963686229606871"><span class="__cf_email__" data-cfemail="93d2e3e3fffaf2fdf0f6c0e7f2fdf7f2e1f7e0c2e6f6e0e7fafcfde0d3f6f6bdf7fcf6bdf4fce5">[email protected]</span></a>. Include docket 
number EERE-2017-BT-STD-0009 in the subject line of the message.
    No telefacsimiles (``faxes'') will be accepted. For detailed 
instructions on submitting comments and additional information on this 
process, see section III of this document.
    Although DOE has routinely accepted public comment submissions 
through a variety of mechanisms, including the Federal eRulemaking 
Portal, email, postal mail, or hand delivery/courier, the Department 
has found it necessary to make temporary modifications to the comment 
submission process in light of the ongoing Covid-19 pandemic. DOE is 
currently suspending receipt of public comments via postal mail and 
hand delivery/courier. If a commenter finds that this change poses an 
undue hardship, please contact Appliance Standards Program staff at 
(202) 586-1445 to discuss the need for alternative arrangements. Once 
the Covid-19 pandemic health emergency is resolved, DOE anticipates 
resuming all of its regular options for public comment submission, 
including postal mail and hand delivery/courier.
    Docket: The docket for this activity, which includes Federal 
Register notices, comments, and other supporting documents/materials, 
is available for review at https://www.regulations.gov. All documents 
in the docket are listed in the www.regulations.gov index. However, 
some documents listed in the index, such as those containing 
information that is exempt from public disclosure, may not be publicly 
available.
    The docket web page can be found at: https://www.regulations.gov/#!docketDetail;D=EERE-2017-BT-STD-0009. The docket web page contains 
instructions on how to access all documents, including public comments, 
in the docket. See section III for information on how to submit 
comments through https://www.regulations.gov.

FOR FURTHER INFORMATION CONTACT: 
    Dr. Stephanie Johnson, U.S. Department of Energy, Office of Energy 
Efficiency and Renewable Energy, Building Technologies Office, EE-5B, 
1000 Independence Avenue SW, Washington, DC 20585-0121. Telephone: 
(202) 287-1943. Email: <a href="/cdn-cgi/l/email-protection#115061617d78707f72744265707f75706375624064746265787e7f625174743f757e743f767e67"><span class="__cf_email__" data-cfemail="501120203c39313e33350324313e34312234230125352324393f3e231035357e343f357e373f26">[email protected]</span></a>.
    Mr. Michael Kido, U.S. Department of Energy, Office of the General 
Counsel, GC-33, 1000 Independence Avenue SW, Washington, DC 20585-0121. 
Telephone: (202) 586-8145. Email: <a href="/cdn-cgi/l/email-protection#9dd0f4fef5fcf8f1b3d6f4f9f2ddf5ecb3f9f2f8b3faf2eb"><span class="__cf_email__" data-cfemail="7a371319121b1f165431131e153a120b541e151f541d150c">[email protected]</span></a>.
    For further information on how to submit a comment or review other 
public comments and the docket, contact the Appliance and Equipment 
Standards Program staff at (202) 287-1445 or by email: 
<a href="/cdn-cgi/l/email-protection#216051514d48404f42447255404f45405345527054445255484e4f526144440f454e440f464e57"><span class="__cf_email__" data-cfemail="713001011d18101f12142205101f15100315022004140205181e1f023114145f151e145f161e07">[email protected]</span></a>.

SUPPLEMENTARY INFORMATION:

Table of Contents

I. Introduction
    A. Authority
    B. Rulemaking History
II. Request for Information
    A. Scope and Equipment Classes
    1. Display Panels
    2. High-Temperature Freezers
    3. Single-Package Refrigeration Systems
    4. Wine Cellar Refrigeration Systems
    B. Significant Savings of Energy
    1. Duty-Cycles and Typical Run Hours
    2. Oversizing Factors
    3. Base-Case Efficiency Distribution
    C. Technological Feasibility
    1. Doors and Panels
    2. Refrigeration Systems
    D. Economic Justification
    1. Markups Analysis--Distribution Channels
    2. Lifetime Analysis
    3. Shipments Analysis
III. Submission of Comments
IV. Issues on Which DOE Seeks Comment

I. Introduction

    DOE has established an early assessment review process to conduct a 
more focused analysis to evaluate, based on statutory criteria, whether 
a new or amended energy conservation standard is warranted. Based on 
the information received in response to the RFI and DOE's own analysis, 
DOE will determine whether to proceed with a rulemaking for a new or 
amended energy conservation standard. If DOE makes an initial 
determination that a new or amended energy conservation standard would 
satisfy the applicable statutory criteria or DOE's analysis is 
inconclusive, DOE would undertake the preliminary stages of a 
rulemaking to issue a new or amended energy conservation standard. If 
DOE makes an initial determination based upon available evidence that a 
new or amended energy conservation standard

[[Page 37688]]

would not meet the applicable statutory criteria, DOE would engage in 
notice and comment rulemaking before issuing a final determination that 
new or amended energy conservation standards are not warranted.

A. Authority

    The Energy Policy and Conservation Act, as amended (``EPCA''),\1\ 
among other things, authorizes DOE to regulate the energy efficiency of 
a number of consumer products and certain industrial equipment. (42 
U.S.C. 6291-6317) Title III, Part C \2\ of EPCA, added by Public Law 
95-619, Title IV, section 441(a) (42 U.S.C. 6311-6317, as codified), 
established the Energy Conservation Program for Certain Industrial 
Equipment, which sets forth a variety of provisions designed to improve 
energy efficiency. This equipment includes walk-in coolers and 
freezers, the subject of this document. (42 U.S.C. 6311(1)(G))
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    \1\ All references to EPCA in this document refer to the statute 
as amended through the Energy Act of 2020, Public Law 116-260 (Dec. 
27, 2020).
    \2\ For editorial reasons, upon codification in the U.S. Code, 
Part C was redesignated Part A-1.
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    Under EPCA, DOE's energy conservation program consists essentially 
of four parts: (1) Testing, (2) labeling, (3) Federal energy 
conservation standards, and (4) certification and enforcement 
procedures. Relevant provisions of EPCA include definitions (42 U.S.C. 
6311), test procedures (42 U.S.C. 6314), labeling provisions (42 U.S.C. 
6315), energy conservation standards (42 U.S.C. 6313), and the 
authority to require information and reports from manufacturers (42 
U.S.C. 6316(a); 42 U.S.C. 6299).
    Federal energy efficiency requirements for covered equipment 
established under EPCA generally supersede State laws and regulations 
concerning energy conservation testing, labeling, and standards. (42 
U.S.C. 6316(a) and (b); 42 U.S.C. 6297) DOE may, however, grant waivers 
of Federal preemption in limited instances for particular State laws or 
regulations, in accordance with the procedures and other provisions set 
forth under 42 U.S.C. 6316(a) (applying the preemption waiver 
provisions of 42 U.S.C. 6297).
    DOE must follow specific statutory criteria for prescribing new or 
amended standards for covered equipment. EPCA requires that any new or 
amended energy conservation standard prescribed by the Secretary of 
Energy (``Secretary'') be designed to achieve the maximum improvement 
in energy efficiency that is technologically feasible and economically 
justified. (42 U.S.C. 6316(a); 42 U.S.C. 6295(o)(2)(A)) The Secretary 
may not prescribe an amended or new standard that will not result in 
significant conservation of energy, or is not technologically feasible 
or economically justified. (42 U.S.C. 6316(a); 42 U.S.C. 6295(o)(3))
    EPCA specifies standards for walk-ins. First, all walk-in doors 
narrower than 3 feet 9 inches and shorter than 7 feet must have 
automatic door closers that firmly close all walk-in doors that have 
been closed to within 1 inch of full closure, and must also have strip 
doors, spring hinged doors, or other methods of minimizing infiltration 
when doors are open. Additionally, walk-ins must contain wall, ceiling, 
and door insulation of at least R-25 for coolers and R-32 for freezers, 
excluding glazed portions of doors and structural members, and floor 
insulation of at least R-28 for freezers. Walk-in evaporator fan motors 
of under 1 horsepower (``hp'') and less than 460 volts must be 
electronically commutated motors (brushless direct current motors) or 
three-phase motors, and walk-in condenser fan motors of under 1 
horsepower must use permanent split capacitor motors, electronically 
commutated motors, or three-phase motors. Interior light sources must 
have an efficacy of 40 lumens per watt or more, including any ballast 
losses; less-efficacious lights may only be used in conjunction with a 
timer or device that turns off the lights within 15 minutes of when the 
walk-in is unoccupied. See 42 U.S.C. 6313(f)(1).
    Second, walk-ins have requirements related to electronically 
commutated motors used in them. See 42 U.S.C. 6313(f)(2)). 
Specifically, in those walk-ins that use an evaporator fan motor with a 
rating of under 1 hp and less than 460 volts, that motor must be either 
a three-phase motor or an electronically commutated motor.\3\ (42 
U.S.C. 6313(f)(2)(A))
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    \3\ The requirement regarding electronically commutated motors 
was predicated on DOE determining that more than one manufacturer 
offered such motors for sale. See 42 U.S.C. 6313(f)(2)(A). DOE 
documented this determination in Docket EERE-2008-BT-STD-0015-0072 
(available at www.regulations.gov/document/EERE-2008-BT-STD-0015-0072).
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    Third, EPCA requires that walk-in freezers with transparent reach-
in doors must have triple-pane glass with either heat-reflective 
treated glass or gas fill for doors and windows. Transparent walk-in 
cooler doors must have either double-pane glass with heat-reflective 
treated glass and gas fill or triple-pane glass with heat-reflective 
treated glass or gas fill. (42 U.S.C. 6313(f)(3)(A)-(B)) For walk-ins 
with transparent reach-in doors, EPCA also prescribes specific anti-
sweat heater-related requirements: Walk-ins without anti-sweat heater 
controls must have a heater power draw of no more than 7.1 or 3.0 watts 
per square foot of door opening for freezers and coolers, respectively. 
Walk-ins with anti-sweat heater controls must either have a heater 
power draw of no more than 7.1 or 3.0 watts per square foot of door 
opening for freezers and coolers, respectively, or the anti-sweat 
heater controls must reduce the energy use of the heater in a quantity 
corresponding to the relative humidity of the air outside the door or 
to the condensation on the inner glass pane. See 42 U.S.C. 
6313(f)(3)(C)-(D).
    Additionally, EPCA prescribed two cycles of WICF-specific 
rulemakings; the first to establish performance-based standards that 
achieve the maximum improvement in energy that the Secretary determines 
is technologically feasible and economically justified, and the second 
to determine whether to amend those standards. (42 U.S.C. 6313(f)(4) 
and (5)) EPCA also requires that, not later than 6 years after the 
issuance of any final rule establishing or amending a standard, DOE 
evaluate the energy conservation standards for each type of covered 
equipment, including those at issue here, and publish either a 
notification of determination that the standards do not need to be 
amended, or a notice of proposed rulemaking (``NOPR'') that includes 
new proposed energy conservation standards (proceeding to a final rule, 
as appropriate). (42 U.S.C. 6316(a); 42 U.S.C. 6295(m)(1)) DOE is 
publishing this RFI to inform its decision consistent with its 
obligations under EPCA.

B. Rulemaking History

    On June 3, 2014, DOE published a final rule (``June 2014 ECS final 
rule'') establishing performance-based standards for the components of 
a walk-in: Doors, panels, and refrigeration systems. 79 FR 32050. The 
standards were expressed in terms of daily energy consumption for walk-
in doors, R-value for walk-in panels, and annual walk-in energy factor 
(``AWEF'') for walk-in refrigeration systems. Id.
    After publication of the June 2014 ECS final rule, the Air-
Conditioning, Heating and Refrigeration Institute (``AHRI'') and Lennox 
International, Inc. (``Lennox''), a manufacturer of walk-in 
refrigeration systems, filed petitions for review of DOE's final rule 
and DOE's subsequent denial of a petition for reconsideration of the 
rule (79 FR 59090 (October 1, 2014)) with the United States Court of 
Appeals for the Fifth Circuit. Lennox Int'l v. Dep't of Energy, Case 
No. 14-60535 (5th Cir.). As a result

[[Page 37689]]

of this litigation, a settlement agreement was reached to address, and 
a controlling order from the Fifth Circuit vacated, standards for six 
of the refrigeration system equipment classes--the two energy 
conservation standards applicable to multiplex condensing refrigeration 
systems (subsequently re-named as ``unit coolers'') operating at medium 
and low temperatures and the four energy conservation standards 
applicable to dedicated condensing refrigeration systems operating at 
low temperatures.\4\ After the Fifth Circuit issued its order, DOE 
established a Working Group to negotiate energy conservation standards 
to replace the six vacated standards. 80 FR 46521 (August 5, 2015). The 
Working Group assembled their recommendations into a Term Sheet (See 
Docket EERE-2015-BT-STD-0016-0056) \5\ that was presented to, and 
approved by, the Appliance Standards and Rulemaking Federal Advisory 
Committee (``ASRAC'') on December 18, 2015.
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    \4\ The thirteen other standards established in the June 2014 
ECS final rule (i.e., the four standards applicable to dedicated 
condensing refrigeration systems operating at medium-temperatures; 
the three standards applicable to panels; and the six standards 
applicable to doors) were not vacated.
    \5\ The docket can be accessed at www.regulations.gov/docket/EERE-2015-BT-STD-0016.
---------------------------------------------------------------------------

    The Term Sheet contained recommended energy conservation standards 
to replace the six vacated standards, definitions for a number of WICF-
related terms, and test procedure changes to implement the recommended 
energy conservation standards. Consequently, DOE initiated both an 
energy conservation standard rulemaking and a test procedure rulemaking 
in 2016 to implement these recommendations. The Term Sheet also 
recommended additional specific test procedure changes for future 
rulemaking to help improve its ability to be fully representative of 
walk-in energy use.
    On July 10, 2017, DOE published a final rule adopting energy 
conservation standards for the six classes of walk-in refrigeration 
systems for which the prior standards were vacated. 82 FR 31808 (``July 
2017 ECS final rule''). The energy conservation standards established 
in the July 2017 ECS final rule were consistent with those recommended 
by the Working Group and approved by ASRAC. 82 FR 31808, 31878. The 
current energy conservation standards for walk-ins are codified at 10 
CFR 431.306.

II. Request for Information

    DOE is publishing this RFI to collect data and information during 
the early assessment review to inform its decision, consistent with its 
obligations under EPCA, as to whether the Department should proceed 
with an energy conservation standards rulemaking. DOE has identified 
certain topics for which information and data are requested to assist 
in the evaluation of the potential for amended energy conservation 
standards. DOE also welcomes comments on other issues relevant to its 
early assessment that may not specifically be identified in this 
document.

A. Scope and Equipment Classes

    This RFI covers equipment meeting the walk-in definition codified 
in 10 CFR 431.302: An enclosed storage space (i.e., box) refrigerated 
to temperatures (1) above 32 [deg]F for walk-in coolers and (2) at or 
below 32 [deg]F for walk-in freezers, that can be walked into, and has 
a total chilled storage area of less than 3,000 square feet, but 
excluding equipment designed and marketed exclusively for medical, 
scientific, or research purposes. 10 CFR 431.302. (See also 42 U.S.C. 
6311(20)) DOE has codified and established energy conservation 
standards applicable to the principal components that make up a walk-in 
(i.e., doors, panels, and refrigeration systems). In addition to the 
prescriptive requirements for walk-ins established by EPCA (42 U.S.C. 
6313(f)(3)(A)-(D)) and codified at 10 CFR 431.306(a)-(b), DOE 
established performance-based energy conservation standards for doors 
and refrigeration systems. 10 CFR 431.306(c)-(e).
    When evaluating and establishing energy conservation standards, DOE 
may divide covered equipment into classes by the type of energy used, 
or by capacity or other performance-related features that would justify 
a different standard. (42 U.S.C. 6316(a); 42 U.S.C. 6295(q)(1)) In 
making a determination whether capacity or another performance-related 
feature justifies a different standard, DOE must consider such factors 
as the utility of the feature to the consumer and other factors DOE 
deems appropriate. Id.
    DOE established standards for walk-in doors based on (1) whether 
they are used in a walk-in cooler (i.e., medium-temperature) or walk-in 
freezer (i.e., low-temperature), (2) whether they are display or non-
display doors,\6\ and (3) if non-display, whether they are passage or 
freight doors.\7\ 10 CFR 431.306(c)-(d). Table II.1 presents the 
equipment classes for all walk-in doors.
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    \6\ A ``display door'' is a door that (1) is designed for 
product display, or (2) has 75 percent or more of its surface area 
composed of glass or another transparent material. 10 CFR 431.302.
    \7\ A ``freight door'' is a door that is not a display door and 
is equal to or larger than 4 feet wide and 8 feet tall. 10 CFR 
431.302. A ``passage door'' is a door that is not a freight or 
display door. Id.
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    DOE codified standards for non-display panels: Based on (1) whether 
they are used in a walk-in cooler (i.e., medium-temperature) or walk-in 
freezer (i.e., low-temperature), and (2) whether they are structural 
(wall or ceiling) or floor panels. 10 CFR 431.306(a)(3)-(4). Table II.2 
presents the equipment classes for walk-in panels.
    DOE established equipment classes for walk-in refrigeration systems 
based on (1) whether they are dedicated condensing systems \8\ or unit 
coolers,\9\ and (2) whether they are used in a walk-in cooler (i.e., 
medium-temperature) or walk-in freezer (i.e., low-temperature). 10 CFR 
431.306(e). DOE further divided dedicated condensing refrigeration 
systems into ``indoor'' and ``outdoor'' equipment classes.\10\ Id. 
``Indoor, low temperature'' dedicated condensing systems, ``outdoor, 
low temperature'' dedicated condensing systems,'' and ``low 
temperature'' unit coolers are further divided based on net capacity. 
See 10 CFR 431.306(e). Table II.3 lists the equipment classes for WICF 
refrigeration systems.
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    \8\ A ``dedicated condensing system'' is one of the following: 
(1) A dedicated condensing unit; (2) A single-package dedicated 
system; or (3) A matched refrigeration system. 10 CFR 431.302.
    \9\ The term, ``unit cooler'' means ``an assembly, including 
means for forced air circulation and elements by which heat is 
transferred from air to refrigerant, thus cooling the air, without 
any element external to the cooler imposing air resistance.'' 10 CFR 
431.302.
    \10\ An ``indoor dedicated condensing refrigeration system'' is 
a ``dedicated condensing refrigeration system designated by the 
manufacturer for indoor use or for which there is no designation 
regarding the use location.'' 10 CFR 431.302. An ``outdoor dedicated 
condensing refrigeration system'' is a ``dedicated condensing 
refrigeration system designated by the manufacturer for outdoor 
use.'' Id.

             Table II.1--Equipment Classes for Walk-In Doors
------------------------------------------------------------------------
             Utility                  Temperature         Class code
------------------------------------------------------------------------
Display Door....................  Medium............  DD.M.
                                  Low...............  DD.L.
Passage Door (Non-display)......  Medium............  PD.M.
                                  Low...............  PD.L.
Freight Door (Non-display)......  Medium............  FD.M.
                                  Low...............  FD.L.
------------------------------------------------------------------------


[[Page 37690]]


            Table II.2--Equipment Classes for Walk-In Panels
------------------------------------------------------------------------
            Utility                 Temperature          Class code
------------------------------------------------------------------------
Floor Panel....................  Low..............  FP.L.
Structural (Wall or Ceiling)     Medium...........  SP.M.
 Panel.                          Low..............  SP.L.
------------------------------------------------------------------------


                         Table II.3--Equipment Classes for Walk-In Refrigeration Systems
----------------------------------------------------------------------------------------------------------------
                                                                             Refrigeration
           System type                Temperature     Condenser location      system net          Class code
                                                                           capacity (Btu/h)
----------------------------------------------------------------------------------------------------------------
Dedicated Condensing............  Medium............  Indoor............  All Capacities....  DC.M.I.
                                                      Outdoor...........  All Capacities....  DC.M.O.
                                  Low...............  Indoor............  <6,500............  DC.L.I, <6,500.
                                                                          >=6,500...........  DC.L.I, >=6,500.
                                                      Outdoor...........  <6,500............  DC.L.O, <6,500.
                                                                          >=6,500...........  DC.L.O >=6,500.
Unit Cooler.....................  Medium............                      All Capacities....  UC.M.
                                  Low...............                      <15,500...........  UC.L, <15,500.
                                                                          >=15,500..........  UC.L, >=15,000.
----------------------------------------------------------------------------------------------------------------

    The applicability of these current equipment classes for certain 
walk-in products is discussed in more detail in sections II.A.1 through 
II.A.4 of this document.
1. Display Panels
    A display panel is defined as a panel that is entirely or partially 
comprised of glass, a transparent material, or both, and is used for 
display purposes. 10 CFR 431.302. DOE has established a test procedure 
for calculating total daily energy consumption, based on measured 
thermal transmittance (also ``U-factor''), of display panels. 10 CFR 
431.304(b)(1). DOE has not, however, adopted standards for display 
panels based on energy consumption as at the time of the June 2014 ECS 
final rule such panels made up a small fraction of the panel market and 
had a limited energy savings potential. 79 FR 32049, 32067. DOE has 
identified two manufacturers of display doors who also manufacture 
display panels.\11\ Some models of these display panels contain anti-
sweat heaters to prevent condensation similar to display doors.
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    \11\ Display panel product information from two manufacturers 
can be found at www.regulations.gov Docket No. EERE-2017-BT-STD-
0009-0001 and Docket No. EERE-2017-BT-STD-0009-0002.
---------------------------------------------------------------------------

    Issue 1: DOE seeks information regarding the thermal transmission 
through display panels and design characteristics which would affect 
the thermal transmission, specifically, ``glass pack'' \12\ design and 
frame design. DOE also seeks information regarding the amount of direct 
electrical energy consumption of electricity-consuming devices sited on 
or within display panels, including the amount of anti-sweat heat 
required, if any. DOE additionally requests information on any specific 
design or use characteristics differentiating display panels from 
display doors.
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    \12\ The ``glass pack'' in a display door or window of a non-
display door is an assembly of glass layers typically filled with 
low thermal-conductivity inert gas and held together at the edges of 
the glass by low-conductivity leak-tight spacers.
---------------------------------------------------------------------------

2. High-Temperature Freezers
    DOE has established a test procedure for determining the net 
capacity and AWEF of walk-in refrigeration systems at appendix C to 
subpart R of 10 CFR part 431 (``Appendix C''), which incorporates by 
reference AHRI Standard 1250P (I-P), ``2009 Standard for Performance 
Rating of Walk-In Coolers and Freezers,'' (``AHRI 1250-2009''). 10 CFR 
431.304(b)(4). As defined previously, the storage space (i.e., box) of 
a walk-in cooler is refrigerated to temperatures above 32 [deg]F, while 
walk-in freezers are refrigerated to temperatures at or below 32 
[deg]F. 42 U.S.C. 6311(20). See also 10 CFR 431.302. The current walk-
in test procedure rates medium-temperature refrigeration systems (which 
are used in walk-in coolers) at 35 [deg]F and low-temperature 
refrigeration systems (which are used in walk-in freezers) at -10 
[deg]F. (See section 5 of AHRI 1250-2009 (dry bulb temperature 
specifications) (incorporated by reference at 10 CFR 431.303(b))) 
Consequently, refrigeration system energy use for walk-in coolers is 
represented by performance at a 35 [deg]F box temperature and 
refrigeration system energy use for walk-in freezers is represented by 
performance at a -10 [deg]F box temperature.
    As discussed in the July 2017 ECS final rule, stakeholders 
commented that so-called ``high-temperature'' freezer walk-ins are 
those with a box temperature range of 10 [deg]F to 32 [deg]F, and that 
medium-temperature refrigeration systems are generally used for this 
temperature range. 82 FR 31808, 31830. As discussed in a RFI published 
on June 17, 2021 (``June 2021 TP RFI''), high-temperature freezers 
would be considered walk-in freezers because their room temperature is 
less than or equal to 32 [deg]F, and would therefore be rated at -10 
[deg]F. 86 FR 32332, 32349. To the extent a medium-temperature 
refrigeration system is used for high-temperature freezer applications, 
such a system may not be able to operate at the -10 [deg]F room 
temperature prescribed by the test procedure for freezers. 81 FR 95758, 
95790. Although the capacity of medium-temperature models measured at 
high-temperature freezer application temperatures is commonly reported 
in product literature, energy use levels are not.\13\
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    \13\ Product literature showing capacity measurements of medium-
temperature models used in high-temperature freezer applications 
from two manufacturers can be found at www.regulations.gov Docket 
No. EERE-2017-BT-STD-0009-0003 and Docket No. EERE-2017-BT-STD-0009-
0004.
---------------------------------------------------------------------------

    Issue 2: DOE requests comment on (1) whether there are medium-
temperature refrigeration system models that are used exclusively in 
high temperature freezers, and (2) if a medium-temperature 
refrigeration system is efficient for cooler applications, will it also 
be efficient for use in high-temperature freezer applications. To the 
extent available, DOE requests data on dedicated condensing unit energy 
efficiency ratio (``EER'') at both high-

[[Page 37691]]

temperature freezer and medium-temperature refrigeration operation.
    See section II.C.2.a for more discussion on high-temperature 
freezers.
3. Single-Package Refrigeration Systems
    Single-package refrigeration systems are considered a type of 
dedicated condensing refrigeration system. 81 FR 95758, 95763. Many 
single-package systems are constructed in such a way that the entire 
refrigeration system is located outside of the refrigerated space; the 
package is typically mounted either on top of, or directly adjacent to 
the walk-in enclosure. Due to this construction, single-package systems 
may experience additional thermal losses not observed in split systems. 
Specifically, single-package systems circulate air through a ``cold 
section'' (evaporator, fan(s), and internal ducting) that may have 
exterior surfaces exposed to the warm air outside of the walk-in 
enclosure and/or the warm condensing unit side of the refrigeration 
system. This configuration can lead to conduction and/or infiltration 
thermal losses which represent a reduction in net capacity and 
efficiency.
    As discussed in the June 2021 TP RFI, DOE is considering whether 
test procedure modifications are necessary to more appropriately 
address the conduction and/or infiltration thermal losses for single-
package systems. 86 FR 32332, 32343-32344. To the extent that these 
losses are accounted for in the test procedure, technology options that 
mitigate such losses would reduce energy consumption and increase AWEF. 
Given the differences in construction between single-package and split 
systems and the potential for differentiated design options, DOE 
intends to separately evaluate single-package system representative 
units in its engineering and downstream analyses.
    Issue 3: DOE requests data and information on the impact of single-
package system design limitations on efficiency and how single-package 
systems differ from split systems. DOE additionally requests 
information showing the trend of efficiency as a function of capacity 
for single-package refrigeration systems.
    See section II.C.2.a for more discussion on single-package 
refrigeration systems.
4. Wine Cellar Refrigeration Systems
    As discussed in the June 2021 TP RFI, DOE has received requests for 
waiver and interim waiver from several manufacturers from the test 
procedure in Appendix C for walk-in wine cellar refrigeration systems. 
86 FR 32332, 32344-32346. These systems are typically designed to 
provide a cold environment at a temperature range between 45-65 [deg]F 
with 50-70 percent relative humidity (``RH''), and typically are kept 
at 55 [deg]F and 55 percent RH.
    The wine cellar refrigeration systems addressed in waiver petitions 
are sold as single-package systems, matched-pair systems, and unit 
cooler-only systems. The minimum capacity of available wine cellar 
refrigeration systems is lower than that of other walk-in cooler units 
(e.g., capacity can be as low as 1,100 Btu/h \14\ as compared with 
4,200 Btu/h for the lowest-capacity medium-temperature dedicated 
condensing unit currently listed in the DOE Compliance Certification 
Management System (``CCMS'') database).\15\ One manufacturer, 
Vinotheque, has noted that there are size constraints for wine cellar 
refrigeration systems. 86 FR 11961, 11972 (March 1, 2021). 
Additionally, certain wine cellar units can be ducted as an option--
either on the condensing unit side, the evaporator side, or both--for 
greater installation flexibility. This factor increases fan energy use. 
Compressors that are typically available for use in lower-capacity wine 
cellar refrigeration systems are of a ``hermetic reciprocating'' 
design,\16\ which generally has a lower efficiency than the larger-
capacity compressors used for low- and medium-temperature walk-in 
refrigeration systems. Finally, as discussed previously, single-package 
wine cellar systems are also subject to additional thermal losses. DOE 
intends to conduct a separate analysis for wine cellar refrigeration 
systems in its engineering and downstream analyses.
---------------------------------------------------------------------------

    \14\ Product literature for a wine cellar refrigeration system 
with a capacity of 1,130 Btu/h from one manufacturer can be found at 
www.regulations.gov Docket No. EERE-2017-BT-STD-0009-0005.
    \15\ U.S. Department of Energy's Compliance Certification 
Database, www.regulations.doe.gov/certification-data/CCMS-4-Walk-In_Coolers_and_Freezers_-_Refrigeration_Systems.html#q=Product_Group_s%3A%22Walk-In%20Coolers%20and%20Freezers%20-%20Refrigeration%20Systems%22, Last 
Accessed: February 2, 2021.
    \16\ In a ``hermetic'' compressor, the compressor and motor are 
both contained in a single outer welded steel shell. Reciprocating 
compressors have a piston that slides back and forth in a cylinder. 
Refrigerant gas is drawn in through a suction valve as the piston 
moves away from the cylinder head, increasing the internal volume, 
and is compressed and discharged through a discharge valve as the 
piston returns. ``Hermetic reciprocating'' compressors are 
hermetically sealed with a reciprocating function.
---------------------------------------------------------------------------

    Issue 4: DOE seeks information on how trends in wine cellar 
installations (e.g., commercial vs. residential, square footage, etc.) 
are expected to impact the type of refrigeration system (i.e., single-
package, matched-pair, dedicated condensing unit, or unit cooler 
system) used in wine cellars over the next 5 to 10 years. Additionally, 
DOE requests information and data on the extent to which capacity may 
impact the efficiency of wine cellar refrigeration systems.

B. Significant Savings of Energy

    As part of the rulemaking process, DOE conducts an energy use 
analysis to identify how a given equipment type is used, and thereby 
determine the energy savings potential of energy efficiency 
improvements.
    The energy use analysis estimates the annual energy consumption of 
refrigeration systems (dedicated condensing systems and unit coolers) 
serving walk-ins, and the energy consumption, and losses, that can be 
directly ascribed to the selected components of the WICF envelopes 
(doors and panels). These estimates are used in the subsequent 
consumer, and National Impacts Analysis.
    The estimates for the annual energy consumption of each analyzed 
representative refrigeration system were derived assuming that (1) the 
refrigeration system is sized such that it follows a specific daily 
duty cycle for a given number of hours per day at full-rated capacity, 
and (2) the refrigeration system produces no additional refrigeration 
effect for the remaining period of the 24-hour cycle. These assumptions 
are consistent with the present industry practice for sizing 
refrigeration systems. This methodology assumes that the refrigeration 
system is correctly paired with an envelope (e.g., panels, door, etc.) 
that generates a load profile such that the rated hourly capacity of 
the paired refrigeration system, operated for the given number of run 
hours per day, produces sufficient refrigeration to meet the daily 
refrigeration load of the envelope with a safety margin to meet 
contingency situations. Thus, the annual energy consumption estimates 
for the refrigeration system depend on the methodology adopted for 
sizing, including implied assumptions and the extent of oversizing.
    While DOE is particularly interested in comment, information, and 
data on the following issues, this request for information is not 
strictly limited to them.
1. Duty-Cycles and Typical Run Hours
    For both the June 2014 ECS final rule and July 2017 ECS final rule 
analyses, DOE used nominal daily run-times of 16 hours for coolers, and 
18 hours for freezers to estimate the in-field energy

[[Page 37692]]

use of walk-in refrigeration systems.\17\ These run-times assume a 
capacity for a ``perfectly''-sized refrigeration system at specified 
reference ambient temperatures of 95 [deg]F and 90 [deg]F for 
refrigeration systems with outdoor and indoor dedicated condensing 
units, respectively. 79 FR 32050, 32083 and 82 FR 31808, 31842. Nominal 
run-time hours for coolers and freezers were adjusted to account for 
equipment over-sizing safety margins and capacity mismatch factors (see 
section II.B.2. of this document). They were further adjusted to 
account for the change in net capacity from increased efficiency 
projected to occur in the standards case, and, in the case of outdoor 
equipment, variations in ambient temperature.\18\ As discussed in the 
prior section, single-package refrigeration systems, high-temperature 
freezers, and wine cellars may have different run-times or be subject 
to different assumptions regarding sizing and ambient temperatures.
---------------------------------------------------------------------------

    \17\ This methodology differs from the run-times established in 
DOE's test procedure, which assumes a high-load period of 8 hours 
corresponding to frequent door openings, equipment loading events, 
and other design load factors, and a low-load period for the 
remaining 16 hours. In the June 2014 ECS final rule analyses, DOE 
concluded that these duty cycle assumptions should not be used for 
sizing purposes because they may not represent the average 
conditions for WICF refrigeration systems for all applications under 
all conditions. 79 FR 32050, 32083. These assumptions were 
maintained in the July 2017 ECS final rule. 82 FR 31808, 31842. DOE 
also notes that while 16 and 18 hours were assumed for coolers and 
freezers, respectively, these assumptions may not be appropriate for 
wine cellars, for which test procedure waiver alternate test 
procedures were established based on an expectation that typical 
operating time is 50 percent. (See: www.energy.gov/eere/buildings/current-test-procedure-waivers#walk-ins for the list of all waivers 
to test procedures that DOE has granted for walk-in coolers and 
freezers).
    \18\ See Chapter 6 of the Technical Support Document (``TSD'') 
for the July 2017 ECS final rule. Docket EERE-2015-BT-STD-0016-0099.
---------------------------------------------------------------------------

    Issue 5: DOE seeks input and data as to the daily run-time hours, 
sizing practice, and ambient conditions for the following: Single-
package refrigeration systems, high-temperature freezers, and wine 
cellars described in sections II.A.2 through II.A.4 of this document. 
DOE also requests information and data regarding any other aspects of 
the operation of such equipment that would influence run-time hours.
    In its analysis supporting the June 2014 ECS final rule, DOE used 
the percent time off (``PTO'') value defined in the test procedure and 
engineering analysis to adjust the nominal direct electrical energy 
usage attributed to the anti-sweat heater (in kilowatt-hours per day 
(``kWh/day'')). The PTO values were applied as set forth in section 
4.4.2(2) of appendix A to subpart R of 10 CFR part 431: 75 percent for 
anti-sweat heaters with timers, control systems, or other demand-based 
controls in cooler doors, and 50 percent for anti-sweat heaters with 
timers, control systems, or other demand-based controls in freezer 
doors. DOE is aware that some manufacturers design and market display 
doors for high-humidity cooler applications.\19\
---------------------------------------------------------------------------

    \19\ Product data sheets from two manufacturers that produce 
walk-in cooler display doors marketed for high-humidity applications 
can be found at www.regulations.gov, Docket No. EERE-2017-BT-STD-
0009-0006 and EERE-2017-BT-STD-0009-0007.
---------------------------------------------------------------------------

    Issue 6: DOE seeks input and data on the appropriate PTO values for 
display doors that would be exposed to higher levels of humidity. 
Specifically, DOE requests information on high-humidity walk-in cooler 
doors, including the range of typical installation conditions (e.g., 
relative humidity throughout the year in store). DOE also requests data 
on the average amount of time per day or per year that anti-sweat 
heaters with timers, control systems, or demand-based controls \20\ are 
operating at their full power and partial power (if applicable) for 
walk-in cooler display doors marketed for high-humidity applications.
---------------------------------------------------------------------------

    \20\ For anti-sweat heaters, demand-based controls monitor 
humidity and temperature external to the walk-in and regulate anti-
sweat heater wire use on demand.
---------------------------------------------------------------------------

2. Oversizing Factors
    In both the June 2014 ECS final rule and July 2017 ECS final rule, 
DOE assumed that WICF refrigeration condensing systems and unit coolers 
in the field are sized to account for a ``worst case scenario'' need 
for refrigeration to prevent food spoilage, and as such are oversized 
by a safety margin. 79 FR 32050, 32083 and 82 FR 31808, 31842. DOE 
found that it is customary in the industry to add a 10 percent safety 
margin to the aggregate 24-hour load, resulting in 10 percent 
oversizing of the refrigeration system. Id. Additionally, DOE 
recognized that an exact match for the calculated refrigeration system 
capacity may not be available for the refrigeration systems available 
in the market because most refrigeration systems are produced in 
discrete capacities. To account for this situation, DOE applied a 
capacity mismatch factor of 10 percent to capture the inability to 
perfectly match the calculated WICF capacity with the capacity 
available in the market. 79 FR 32050, 32084 and 82 FR 31808, 31842. The 
combined safety margin factor and capacity mismatch factor result in a 
total oversizing factor of 1.2. With the oversize factor applied, the 
nominal run-time hours of the refrigeration system are reduced to 13.3 
hours from 16 hours per day for coolers, and to 15 hours from 18 hours 
per day for freezers at their respective full design point capacity. 79 
FR 32050, 32083 and 82 FR 31808, 31842.
    Issue 7: DOE seeks input on whether the combined safety and 
capacity mismatch oversizing factors for adjusting daily nominal run-
time hours relied on in the June 2014 ECS final rule and the July 2017 
ECS final rule are appropriate for single-package refrigeration 
systems, high-temperature freezers, and wine cellars as described in 
sections II.A.2 through II.A.4 of this document. If different factors 
would be appropriate for such equipment, DOE requests data in support 
of alternate assumptions.
3. Base-Case Efficiency Distribution
    DOE measures savings of potential standards relative to a ``no-new-
standards'' case that reflects conditions without new and/or amended 
standards. The no-new-standards case reflects the distribution of 
equipment efficiency or energy use beginning at the baseline 
performance level. The baseline performance level in each equipment 
class represents the characteristics of common or typical equipment in 
that class. If there is an established DOE energy conservation standard 
for the class, the baseline performance level coincides with the 
current minimum energy conservation standard and provides basic end-
user utility. However, not all models in an equipment class may be 
rated at the baseline performance level. DOE uses efficiency market 
shares to characterize the no-new-standards case equipment mix. By 
accounting for consumers who already purchase more-efficient equipment, 
DOE avoids overstating the potential benefits from potential standards.
    In the July 2017 ECS final rule, DOE assumed that 100 percent of 
WICF refrigeration equipment is sold at the baseline efficiency level 
in the absence of new and/or amended standards. (Docket No. EERE-2015-
BT-STD-0016, Public Meeting, No. 68 at pp. 53-54) These assumptions did 
not include medium-temperature condensing systems (which were not 
within the scope of that rulemaking). Medium-temperature condensing 
systems were included in the June 2014 ECS final rule where DOE assumed 
that 75 percent of shipments were baseline equipment, with the 
remaining 25 percent at the efficiency of the first design option above 
baseline. 79 FR 32050, 32087. DOE understands that these assumptions 
may not reflect the current

[[Page 37693]]

state of the market due to adoption of more stringent efficiency 
standards.
    Next, DOE examined the ratings for walk-in refrigeration systems 
reported in DOE's CCMS.\21\ The number of models at or above the 
current standards are shown in Table II.4. These data show the count of 
models distributed in commerce with their respective efficiency 
ratings; however, these data do not indicate the volume of shipments of 
each model.
---------------------------------------------------------------------------

    \21\ Please see footnote 15.

                       Table II.4--Distribution of Efficiencies for Refrigeration Systems
----------------------------------------------------------------------------------------------------------------
                                                                                     Count of       Percent of
                         Equipment class                             Count of        models at       models at
                                                                      models         baseline        baseline
----------------------------------------------------------------------------------------------------------------
UC.L............................................................           3,899           1,618              41
DC.L.O..........................................................           1,780           1,438              81
DC.L.I..........................................................             877             825              94
UC.M............................................................           5,228           3,222              62
DC.M.O..........................................................           2,722           2,057              76
DC.M.I..........................................................           1,145             956              83
----------------------------------------------------------------------------------------------------------------

    In the June 2014 ECS final rule DOE assumed that: (1) All panels 
and non-display door shipments were at the baseline; (2) 25 percent of 
display low-temperature door shipments were at the baseline, with the 
remaining 75 percent at a higher efficiency (45 percent were assumed to 
have light emitting diode (``LED'') lighting, corresponding to the 
first design option above the baseline in the engineering analysis, and 
30 percent were assumed to have LED lighting plus anti-sweat heater 
wire controls, corresponding to the second design option above the 
baseline); and (3) 80 percent of medium-temperature display doors 
shipments were at baseline and the remaining 20 percent would have LED 
lighting, corresponding to the first design option above the baseline 
for low-temperature display doors. 79 FR 32050, 32087. DOE understands 
that these assumptions may not reflect the current state of the market 
due to adoption of more stringent efficiency standards.
    Next, DOE examined the ratings for walk-in doors and panels 
reported in the CCMS. The number of models at or above the current 
standards are shown in Table II.5.\22\ Again, these data show the count 
of models distributed in commerce with their respective efficiency 
ratings; however, these data do not indicate the volume of shipments of 
each model.
---------------------------------------------------------------------------

    \22\ U.S. Department of Energy's Compliance Certification 
Database, www.regulations.doe.gov/certification-data/CCMS-4-Walk-In_Coolers_and_Freezers_-_Doors.html#q=Product_Group_s%3A%22Walk-In%20Coolers%20and%20Freezers%20-%20Doors%22; and 
www.regulations.doe.gov/certification-data/CCMS-4-Walk-In_Coolers_and_Freezers_-_Panels.html#q=Product_Group_s%3A%22Walk-In%20Coolers%20and%20Freezers%20-%20Panels%22, Last Accessed: March 
17, 2021.

                          Table II.5--Distribution of Efficiencies for Panels and Doors
----------------------------------------------------------------------------------------------------------------
                                                                                     Count of       Percent of
                         Equipment class                             Count of        models at       models at
                                                                      models         baseline        baseline
----------------------------------------------------------------------------------------------------------------
DD.M............................................................           2,861           2,785              97
DD.L............................................................           1,213           1,108              91
PD.M............................................................           1,872             334              18
PD.F............................................................           1,124             604              54
FD.M............................................................             631               0               0
FD.L............................................................             274              95              35
SP.M............................................................              87              14              16
SP.L............................................................              98              50              51
FP.L............................................................              77              13              17
----------------------------------------------------------------------------------------------------------------

    Issue 8: DOE seeks data and information regarding the current, and 
projected future market shares of WICF equipment by efficiency level 
(e.g., expressed in terms of increments of 10 percent improvement in 
AWEF, R-values, and kWh/day for refrigeration systems, panels, and 
doors, respectively, above or below the existing standards in 10 CFR 
431.306) to establish market trends in equipment efficiency over time. 
DOE also seeks information on how the current regulatory environment 
has affected the market share of WICF equipment by efficiency rating.

C. Technological Feasibility

    During the June 2014 ECS final rule and July 2017 ECS final rule, 
DOE considered a number of technologies for reducing walk-in cooler and 
freezer energy consumption.\23\ DOE is interested in understanding any 
technology improvements for walk-in doors, panels, and refrigeration 
systems since the previous energy standards rulemaking. Additionally, 
DOE is interested in any changes to the technologies it evaluated in 
the rulemakings for the June 2014 ECS final rule and July 2017 ECS 
final rule that may affect whether DOE could propose a ``no-new-
standards'' determination, such as an insignificant increase in the 
range of efficiencies and performance characteristics of these 
technologies.
---------------------------------------------------------------------------

    \23\ For a complete list of technology options analyzed during 
the June 2014 and July 2017 ECS final rules, see chapter 3 of 
``TSD'' for each rulemaking. Docket EERE-2008-BT-STD-0015-0131 (June 
2014) and Docket EERE-2015-BT-STD-0016-0099 (July 2017).
---------------------------------------------------------------------------

    While DOE is particularly interested in comment, information, and 
data on the following issues, this request for information is not 
strictly limited to them.
1. Doors and Panels
a. Technology Options
    A complete list of options evaluated in preparation for the June 
2014 ECS

[[Page 37694]]

final rule and explained in the TSD are listed in Table II.6 for doors 
and Table II.7 for panels.\24\ Table II.8 lists additional technology 
options that DOE may consider in a future WICF energy conservation 
standard.
---------------------------------------------------------------------------

    \24\ See sections 3.3.3 to 3.3.6 at pp. 3-26 to 3-30 of the TSD 
for the June 2014 ECS final rule. Docket EERE-2008-BT-STD-0015-0131.

 Table II.6--Technology Options Considered for WICF Doors From the June
                           2014 ECS Final Rule
------------------------------------------------------------------------
                 Component                       Technology options
------------------------------------------------------------------------
Display doors.............................  Non-electric anti-sweat
                                             systems.
                                            Anti-sweat heater wire
                                             controls.
                                            Removal of heater wire.
                                            High-efficiency lighting.
                                            Lighting sensors.
                                            Occupancy sensors.
                                            Automatic insulation
                                             deployment systems.
                                            Enhanced glass systems.
Non-Display Doors.........................  Increased insulation
                                             thickness.
                                            Improved insulation
                                             material.
                                            Improved framing materials.
                                            Heater wire controls.
                                            Enhanced glass systems.
------------------------------------------------------------------------


 Table II.7--Technology Options Considered for WICF Panels From the June
                           2014 ECS Final Rule
------------------------------------------------------------------------
                 Component                       Technology options
------------------------------------------------------------------------
Panels....................................  Increased insulation
                                             thickness.
                                            Improved insulation
                                             material.
------------------------------------------------------------------------


       Table II.8--Potential New Technology Options for WICF Doors
------------------------------------------------------------------------
                 Component                       Technology options
------------------------------------------------------------------------
Display and Non-Display Doors.............  Vacuum insulated glass.
------------------------------------------------------------------------

    Walk-in doors typically use anti-sweat heater wires to prevent (1) 
condensation from collecting on the glass, frame, or any other portion 
of the door, which can puddle and be hazardous to consumers, (2) 
fogging of the glass, and (3) the collecting of condensation that may 
lead to doors freezing shut. DOE has observed that anti-sweat heater 
wires for display doors may be placed within the door rail surrounding 
the glass pack and/or within the surrounding frame. For display doors, 
display panels, and non-display doors with viewing windows, as the 
thermal performance of the glass pack improves, the amount of anti-
sweat heat required for the glass pack decreases. With a more 
insulative glass pack, there is a smaller temperature difference 
between the interior and exterior faces of the glass and the interior 
walk-in and exterior air temperatures, resulting in less condensation 
on the glass. As mentioned in the TSD for the June 2014 ECS final rule, 
DOE based the amount of anti-sweat heater wire energy consumption on 
the glass packs selected.\25\ If a frame does not contain a thermal 
break or has poor insulative properties, despite having a glass pack 
with better insulative performance, the door assembly may still require 
more anti-sweat heat on the surrounding frame to prevent the 
condensation and fogging issues noted earlier.
---------------------------------------------------------------------------

    \25\ See section 5.5.2.3 at p. 5-19 of the TSD for the June 2014 
ECS final rule. Docket EERE-2008-BT-STD-0015-0131.
---------------------------------------------------------------------------

    Issue 9: DOE seeks information on how the physical construction of 
a display door, including the glass pack and the frame, impact the 
amount of anti-sweat heater wire power needed to prevent condensation 
accumulating on any part of the door. Specifically, DOE seeks 
quantitative data, if available, on the change in anti-sweat heater 
power (1) with a specific change in door frame design but no change in 
glass pack design, (2) with a specific change in glass pack design but 
no change in door frame design, and/or (3) with specific changes to the 
entire assembly. If there are specific design choices which are more 
costly but result in less or no anti-sweat heat, DOE requests cost data 
based on the capability of the door to prevent condensation from 
forming and the respective design options chosen. DOE also requests 
comment on any other considerations which may impact the use and power 
of anti-sweat heaters.
    As stated previously, DOE is aware that some manufacturers design 
and market display doors for high-humidity applications. These doors 
generally have anti-sweat heaters with higher rated power than those of 
standard medium-temperature display doors but lower than the power 
required for low-temperature display doors. For example, data from the 
CCMS database show that doors marketed for high-humidity applications 
have a range of anti-sweat heater power per door opening area from 0.39 
to 5.59 watt (``W'')/square foot (``ft\2\''), with the average being 
1.66 W/ft\2\. By comparison, the range of anti-sweat heater power is 
between 0 to 3.74 W/ft\2\ for cooler doors not marketed for high-
humidity applications made by the manufacturers who also produce doors 
marketed for high-humidity applications, with the average being 1.01 W/
ft\2\.
    Issue 10: DOE seeks specific data and information on the 
correlation between relative humidity conditions at installation and 
the anti-sweat heater power needed to prevent condensation from 
accumulating on a walk-in door.
    DOE is also aware that walk-in display door manufacturers may 
produce glass doors for other kinds of refrigeration equipment. DOE has 
specifically observed that some glass doors for commercial 
refrigeration equipment, while appearing very similar in design to 
their walk-in door counterparts, do not include any anti-sweat heaters 
around the door or frame.
    Issue 11: DOE requests comment on the differences in design, 
typical conditions, and usage of a walk-in display door as compared to 
a display door for commercial refrigeration equipment which result in 
commercial refrigeration equipment door designs with no anti-sweat 
heaters.
    Non-display doors (passage and freight doors) typically have better 
insulative properties than display doors because they have little or no 
glass needed for viewing purposes. Door insulation is also subject to a 
minimum R-value. 10 CFR 431.306(a)(3). DOE expects that less anti-sweat 
heat may be needed to prevent condensation accumulation for non-display 
doors because of their improved overall resistance to heat flow as 
compared to display doors. Certified data from DOE's CCMS database,\26\ 
presented in Table II.9, shows that passage and freight doors have 
lower average anti-sweat heater power per area of door opening than 
display doors and a higher percentage of passage and freight doors 
certify 0 W/ft\2\ of anti-sweat heater power per area of door opening 
than display doors. However, the maximum anti-sweat heater power per 
area of door opening for low-temperature passage and freight doors is 
higher than the average for these equipment classes, and the maximum 
for these equipment classes is also higher than the maximum for low-
temperature display doors.
---------------------------------------------------------------------------

    \26\ Please see footnote 22.

[[Page 37695]]



                 Table II.9--Certified Ranges of Anti-Sweat Heater Power per Area of Door Opening for Each Walk-In Door Equipment Class
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                           Display door,   Display door,   Passage door,   Passage door,   Freight door,   Freight door,
                                                              medium            low           medium            low           medium            low
                                                            temperature     temperature     temperature     temperature     temperature     temperature
--------------------------------------------------------------------------------------------------------------------------------------------------------
Minimum (W/ft\2\).......................................            0.00            0.00            0.00            0.00            0.00            0.00
Maximum (W/ft\2\).......................................            5.59            5.39            6.80            7.08            3.40            7.00
Average (W/ft\2\).......................................            1.37            2.99            0.42            1.15            0.11            0.16
Percent of Models without Anti-sweat Heat...............              5%              3%             60%             46%             63%             77%
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Issue 12: DOE seeks specific data and information on how the 
physical construction of both passage and freight doors impact the 
amount of anti-sweat heater wire power needed to prevent condensation 
accumulation on any part of the door. DOE requests specific comment on 
any technologies that may reduce or eliminate the need for anti-sweat 
heat on passage or freight doors. DOE also requests door design 
information and data that explain why many passage and freight doors 
are able to perform without any anti-sweat heater power in the field 
but some doors, specifically low-temperature passage and freight doors, 
still require anti-sweat power that is greater than that required for 
display doors to prevent condensation accumulation.
    As stated previously, DOE may consider technology options for walk-
in doors that were not considered in the June 2014 ECS final rule, 
specifically vacuum-insulated glass packs for display doors and windows 
in non-display doors. DOE has identified two manufacturers that produce 
display doors with vacuum-insulated glass packs.\27\
---------------------------------------------------------------------------

    \27\ Product data sheets from two manufacturers that produce 
display doors with vacuum-insulated glass can be found at 
www.regulations.gov, Docket No. EERE-2017-BT-STD-0009-0008 and 
Docket No. EERE-2017-BT-STD-0009-0009.
---------------------------------------------------------------------------

    Issue 13: DOE requests comment on the prevalence of vacuum-
insulated glass for walk-in doors and whether other manufacturers are 
considering adopting this technology. DOE requests specific feedback on 
any obstacles or concerns (e.g., patents, proprietary use, durability, 
practicability to manufacture, etc.) which would prevent manufacturers 
from using vacuum-insulated glass in walk-in doors. DOE also requests 
cost data for implementing vacuum-insulated glass in walk-in display 
doors.
b. Screening of Technology Options
    Table II.10 lists the technology options that DOE screened out for 
walk-in doors and panels in the TSD for the June 2014 ECS final rule 
and the applicable screening criteria.\28\
---------------------------------------------------------------------------

    \28\ See section 4.3 at p. 4-5 of the TSD for the June 2014 ECS 
final rule. Docket EERE-2008-BT-STD-0015-0131.

                               Table II.10--Doors and Panels Technology Options Screened From the June 2014 ECS Final Rule
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                         EPCA Criteria (X = Basis for Screening Out)
                                                                   -------------------------------------------------------------------------------------
                                                                                      Practicability                        Adverse
                    Screened technology option                       Technological    to manufacture,  Adverse  impact     impacts on    Unique- pathway
                                                                      feasibility      install, and      on  product       health and       proprietary
                                                                                          service          utility           safety        technologies
--------------------------------------------------------------------------------------------------------------------------------------------------------
Non-electric anti-sweat systems...................................               X   ................  ...............  ...............  ...............
Automatic insulation deployment systems...........................               X   ................  ...............  ...............  ...............
Insulation thicker than 6 inches..................................  ...............                X                X   ...............  ...............
--------------------------------------------------------------------------------------------------------------------------------------------------------

    Issue 14: DOE requests feedback on what impact, if any, DOE's 
screening criteria (technological feasibility; practicability to 
manufacture, install, and service; adverse impacts on product utility 
or product availability; adverse impacts on health or safety; and 
unique-pathway proprietary technologies) would have on each of the 
technology options listed in Table II.6, Table II.7, and Table II.8 of 
this document. DOE also seeks information regarding how these same 
criteria would affect any other technology options not already 
identified in this document with respect to their potential use in 
walk-in doors and panels.
    For the 2014 ECS final rule analyses, DOE screened out insulation 
thickness greater than six inches for panels and doors due to concerns 
about panels and doors becoming extremely heavy and unwieldy, long cure 
times for the insulation, and reduced space within the walk-in to store 
product.\29\ DOE has identified one manufacturer that markets panels 
with a thickness range from 2-inches to 10-inches.\30\
---------------------------------------------------------------------------

    \29\ See section 4.3.5 at p. 4-5 of the TSD for the June 2014 
ECS final rule. Docket EERE-2008-BT-STD-0015-0131.
    \30\ Technical data from one manufacturer that produces panels 
ranging from 2-inches to 10-inches thick can be found at 
www.regulations.gov, Docket No. EERE-2017-BT-STD-0009-0010.
---------------------------------------------------------------------------

    Issue 15: DOE requests comment on whether 6 inches is an 
appropriate upper limit for screening out insulation thickness for 
panels and doors. For manufacturers that produce and certify panels 
with insulation thicknesses exceeding 6 inches, DOE requests feedback 
on what manufacturing investments have been made to do so. For 
manufacturers that do not produce panels with insulation thicknesses 
exceeding 6 inches, DOE requests feedback on the obstacles preventing 
them from increasing panel thickness.
c. Representative Units
    In the June 2014 ECS final rule, DOE analyzed representative walk-
in cooler and freezer doors and panels. 79 FR 32050, 32072-37073. The 
representative walk-in doors are presented in Table II.11.

[[Page 37696]]



                Table II.11--Representative Walk-In Doors Evaluated in June 2014 ECS Final Rule *
----------------------------------------------------------------------------------------------------------------
                                                                                                   Window area
            Utility                  Temperature       Representative     Dimensions (height x  (ft\2\) for non-
                                                          unit size           length, ft)         display doors
----------------------------------------------------------------------------------------------------------------
Display Door...................  Cooler............  Small.............  5.25 x 2.25..........  ................
                                                     Medium............  6.25 x 2.25..........  ................
                                                     Large.............  7 x 3................  ................
                                 Freezer...........  Small.............  5.25 x 2.25..........  ................
                                                     Medium............  6.25 x 2.25..........  ................
                                                     Large.............  7 x 3................  ................
Passage Door...................  Cooler............  Small.............  6.5 x 2.5............              2.25
                                                     Medium............  7 x 3................              2.25
                                                     Large.............  7.5 x 4..............              2.25
                                 Freezer...........  Small.............  6.5 x 2.5............              2.25
                                                     Medium............  7 x 3................              2.25
                                                     Large.............  7.5 x 4..............              2.25
Freight Door...................  Cooler............  Small.............  8 x 5................              2.25
                                                     Medium............  9 x 7................              4.00
                                                     Large.............  12 x 7...............              4.00
                                 Freezer...........  Small.............  8 x 5................              2.25
                                                     Medium............  9 x 7................              4.00
                                                     Large.............  12 x 7...............              4.00
----------------------------------------------------------------------------------------------------------------
* See section 5.3.1 at p. 5-3 of the TSD for the June 2014 ECS final rule, Docket EERE-2008-BT-STD-0015-0131.

    For the 2014 ECS final rule, DOE only analyzed single-width display 
doors as representative units in the engineering analysis. However, 
many display doors are sold as multi-door configurations with 2-, 3-, 
4-, or 5-door openings encapsulated within one outer frame. The 
relationship of energy use for a single-width display door may not 
linearly extrapolate for multi-door configurations. For example, a 
single-width door may include two light fixtures, one on each side of 
the door opening, whereas additional doors may add one light fixture 
per door opening. Thus, a single-width door of equal area to a double-
width door would use less lighting power than the double-width door, 
despite being equal in area.
    Issue 16: DOE requests feedback on the representative units for 
display doors used for the 2014 ECS final rule engineering analysis and 
whether multi-door configurations should be included as representative 
units. If so, DOE seeks comment on panel size and the number of panels 
that would be most representative for multi-door configurations. 
Additionally, DOE seeks specific data on the appropriate number of door 
openings and door sizes to consider and the additional electrical 
component power (e.g., anti-sweat heater power, lighting, etc.) 
required for each additional door opening. DOE is also interested in 
any other differences between single-door and multi-door configurations 
that would impact energy use.
    In the June 2021 TP RFI, DOE requested feedback on the current 
definitions of passage and freight doors and whether there were any 
attributes, including size, which distinguish them from each other. 86 
FR 32332, 32335.
    Issue 17: DOE seeks comment on the appropriateness of the 
representative units chosen for the previous analysis of passage and 
freight doors. DOE requests specific feedback on what the minimum and 
maximum sizes of both passage and freight doors are and if there are 
other attributes besides size which differentiate passage doors from 
freight doors and vice versa.
    As discussed in the June 2021 TP RFI, DOE received multiple test 
procedure waivers requesting to increase the percent time off (``PTO'') 
for motorized walk-in door openers. 86 FR 32332, 32338. In the 
engineering analysis for the June 2014 ECS final rule, the 
representative units of walk-in doors analyzed did not include 
motorized door openers. DOE is considering whether motorized door 
openers should be considered in its representative models.
    Issue 18: DOE seeks comment on the prevalence of motorized door 
openers for both display and non-display doors. DOE requests specific 
feedback on the prevalence of motorized door openers by equipment 
class, the minimum door size that might have a motorized door opener, 
the percentage of doors sold which typically include a motorized door 
opener, and any data relating power of a motorized door opener to door 
size.
2. Refrigeration Systems
a. Technology Options
    A complete list of technology options evaluated for refrigeration 
systems in preparation for the June 2014 ECS final rule and July 2017 
ECS final rule is presented in Table II.12.\31\ Table II.13 lists 
additional technology options that DOE may consider in a future WICF 
energy conservation standard.
---------------------------------------------------------------------------

    \31\ See sections 3.3.1 and 3.3.7-3.3.10 at pp. 3-24 through 3-
25 and 3-30 through 3-33 of the TSD for the June 2014 ECS final 
rule. Docket EERE-2008-BT-STD-0015-0131. See section 3.3 at pp. 3-14 
through 3-18 of the TSD for the July 2017 ECS final rule. Docket 
EERE-2015-BT-STD-0016-0099.

    Table II.12--Technology Options Considered for WICF Refrigeration
  Systems in the June 2014 ECS Final Rule and July 2017 ECS Final Rule
------------------------------------------------------------------------
                 Component                       Technology options
------------------------------------------------------------------------
Refrigeration Systems.....................  Energy storage systems.
                                            Refrigeration system
                                             override.
                                            Automatic evaporator fan
                                             shut-off.
                                            Improved evaporator and
                                             condenser fan blades.
                                            Improved evaporator and
                                             condenser coils.
                                            Evaporator fan control.
                                            Ambient sub-cooling.
                                            Higher-efficiency fan
                                             motors.
                                            Higher-efficiency
                                             compressors.
                                            Variable-speed compressors.
                                            Liquid suction heat
                                             exchanger.
                                            Adaptive Defrost.
                                            Hot gas defrost.
                                            Floating head pressure.
                                            Condenser fan control.
                                            Economizer cooling.
------------------------------------------------------------------------


[[Page 37697]]


  Table II.13--Potential New Technology Options for WICF Refrigeration
                                 Systems
------------------------------------------------------------------------
                 Component                       Technology options
------------------------------------------------------------------------
Refrigeration Systems.....................  Improved Thermal Insulation.
                                            Crankcase Heater Controls.
                                            Refrigerant.
------------------------------------------------------------------------

    As discussed in sections II.A.2, II.A.3, and II.A.4 of this 
document, DOE is interested specifically in high-temperature freezers, 
single-package refrigeration systems, and wine cellar refrigeration 
systems and how their particular applications may influence the use of 
the technology options listed in Table II.12 and Table II.13 of this 
document.
    Issue 19: DOE requests comment on whether there are technology 
options or other design features that would be unique to high-
temperature freezer refrigeration systems (i.e., medium-temperature 
systems operating at a temperature between 10 [deg]F to 32 [deg]F) as 
compared to technology options or design features for medium-
temperature refrigeration systems operating at above-freezing (cooler) 
temperatures. If high-temperature freezer refrigeration systems have 
certain unique features, DOE seeks information on those features and 
how they impact refrigeration system performance.
    As discussed in section II.A.3 and II.A.4 of this document, single-
package and wine cellar refrigeration systems have structural designs 
different from other walk-in split systems. Due to differences in 
design, DOE expects that the design options for these products may be 
different from dedicated condensing units and unit coolers sold 
separately.
    Issue 20: DOE requests comment on which of the technology options 
listed in Table II.12 and Table II.13 of this document are available 
and used in single-package refrigeration systems. DOE also requests 
comment on whether there are other technologies that apply to single-
package refrigeration systems not mentioned in Table II.12 or Table 
II.13 of this document. Additionally, DOE requests comment on which 
technology options are feasible for dedicated condensing systems and 
unit coolers but may not be feasible for single-packaged refrigeration 
systems due to structural design constraints.
    Issue 21: DOE requests comment on which of the technology options 
listed in Table II.12 and Table II.13 of this document are available 
and used in wine cellar refrigeration systems. DOE also seeks 
information on whether there are additional technologies that apply to 
wine cellar refrigeration systems that are not mentioned in Table II.12 
or Table II.13 of this document. Additionally, DOE requests comment on 
the specific design constraints for wine cellar refrigeration systems 
and how these constraints may impact the use of certain technology 
options.
    In the July 2017 ECS final rule, DOE considered and ultimately 
screened out improved compressor technology options, such as multiple-
capacity or variable-capacity compressors. 82 FR 31808, 31839. The 
current DOE test procedure does not allow testing of multiple-capacity 
or variable-capacity systems using the condenser-alone rating method. 
Although the test procedure does have provisions for testing multiple-
capacity and variable-capacity matched-pair refrigeration systems, DOE 
did not analyze matched-pair systems in the engineering analysis and 
thus did not further consider this option. 82 FR 31808, 31839. DOE 
requested information and comment on testing multiple-capacity and 
variable-capacity compressors in the June 2021 TP RFI. 86 FR 32332, 
32348-32349.
    Issue 22: DOE seeks information on the availability of multiple-
capacity or variable-capacity compressors in the current market. DOE is 
also interested in any end-user requirements that may restrict the use 
of, or reduce the potential benefits of, multi- or variable-capacity 
compressors in the field.
    In the July 2017 ECS final rule, DOE evaluated scroll compressors 
for smaller capacity systems (capacities between 6,000 Btu/h and 25,000 
Btu/h) and semi-hermetic compressors for larger capacity systems 
(capacities between 25,000 Btu/h and 72,000 Btu/h). 82 FR 31808, 31837-
31838. For most evaluated representative capacities, DOE assigned the 
expected compressor type and did not evaluate compressor type as a 
design option. (At the 25,000 Btu/h overlap representative capacity, 
DOE applied a blended analysis, but also did not consider compressor 
type as a design option for efficiency improvement.) However, DOE is 
aware that some compressor types are more efficient than others. For 
example, a preliminary evaluation of DOE's CCMS database indicates that 
for those reported models with an AWEF value higher than the minimum 
standard, low-temperature dedicated condensing units (less than 25,000 
Btu/h) with semi-hermetic compressors have reported AWEF values six 
percent, on average, higher than similar units that use a scroll 
compressor. DOE is interested in understanding how manufacturers select 
compressors when designing their equipment and the utility advantages 
and disadvantages of scroll versus semi-hermetic compressors over a 
range of capacities for which both compressors types could be 
considered.
    Issue 23: DOE requests comment on the relative efficiency 
difference between scroll and semi-hermetic compressors in the range of 
capacities in which both are available. DOE also requests comment on 
other design parameters that would lead a manufacturer to select a 
certain compressor design over another and would represent potential 
utility differences of different compressor designs, specifically, (1) 
compressor weight relative to the final equipment weight and its impact 
on equipment shipping, installation, and end-use; (2) compressor 
durability, equipment warranty, and equipment lifetime; and (3) any 
other relevant differences.
    DOE is also interested in understanding if other higher efficiency 
single-capacity compressors have become available for use in walk-in 
systems since the last rulemaking. For instance, DOE is interested in 
information on whether some compressors are more efficient than others 
at certain walk-in capacity ranges or operating conditions..
    Issue 24: DOE seeks information on the availability and 
efficiencies of single-speed compressors (e.g., scroll compressors, 
rotary compressors, semi-hermetic compressors) that were not available 
or were not considered in the analysis during the rulemaking finalized 
in 2017. Additionally, DOE is interested in understanding the 
availability of rotary compressors for use in single-package and wine 
cellar refrigeration systems.
    As shown in Table II.13 of this document, DOE is investigating 
crankcase heater controls to understand how they are used in, and the 
field requirements for, outdoor walk-in refrigeration systems. There 
are several types of crankcase heater control systems that are 
available on the market for other types of equipment, specifically, 
central air conditioners and heat pumps (``CACs''). The technical 
support document from the direct final rule amending standards for CACs 
published on January 6, 2017 (``CAC 2017 direct final rule'') provides 
descriptions of different crankcase heater control systems.\32\

[[Page 37698]]

Thermostatically-controlled crankcase heaters adjust whether the heater 
is on or off based on a temperature sensor that measures outdoor 
ambient air. When the outside ambient temperature is high enough the 
heater turns off, thus reducing energy use. (Id.). Self-regulating 
crankcase heaters have control systems that vary the resistivity as a 
function of temperature, thus providing ``internal'' thermostatic 
control to reduce energy use. (Id.) In its testing, DOE has observed 
that some walk-in refrigeration systems have the crankcase heater 
energized 100 percent of the time including when the compressor is 
operating, without demand-based controls. DOE is considering whether 
crankcase heater control technology might be applied to WICF 
refrigeration systems to improve efficiency.
---------------------------------------------------------------------------

    \32\ See sections 3.4.1 at p. 3-34 of the TSD for the CAC 2014 
direct final rule. Docket EERE-2014-BT-STD-0048-0098. The docket and 
supporting materials for the CAC 2017 direct final rule can be 
accessed at www.regulations.gov/docket/EERE-2014-BT-STD-0048.
---------------------------------------------------------------------------

    Issue 25: DOE seeks comment on the prevalence of the use of 
crankcase heater controls for walk-in refrigeration systems. 
Additionally, DOE requests information on what type of crankcase heater 
controls are considered viable, and what application circumstances 
would make certain control approaches inappropriate e.g., by 
unacceptably increasing the chance of compressor failure.
    As discussed in section II.A.3 of this document, single-package 
refrigeration systems are susceptible to thermal losses associated with 
the structural design. Table II.13 lists thermal insulation as a 
potential technology option for these systems. Improved thermal 
insulation may reduce conduction losses, and better sealing of cabinet 
air leaks may reduce infiltration of warm outdoor air.
    Issue 26: DOE seeks information on the potential for improved 
thermal insulation and sealing of air leaks to improve the efficiency 
of single-package refrigeration systems. Specifically, DOE is 
interested in data on the range of typical insulation thickness used in 
single-package systems to insulate the indoor portion, in addition to 
the insulation materials that are typically used. Additionally, DOE 
requests information on the processes and materials that manufacturers 
utilize to ensure airtight enclosures. DOE is also interested in 
understanding the quality control processes manufacturers have in place 
to ensure that airtight units are released to the market.
    Evaluation of outdoor dedicated condensing units in DOE's CCMS 
database \33\ indicate that 86 percent of medium-temperature and 91 
percent of low-temperature models are offered with R-404A, R-407A, R-
448A/R-449A, or R-507A. R-448A/R-449A has low Global Warming Potential 
(``GWP'') compared to R-407A, which in turn has lower GWP than R-404A 
and R-507A. The remaining medium- and low-temperature condensing unit 
models are offered with R-407C, R-407F, and R-52A. Additionally, DOE is 
aware that wine cellar walk-in refrigeration systems are currently 
offered with R-134A.
---------------------------------------------------------------------------

    \33\ Please see footnote 15.
---------------------------------------------------------------------------

    In past rulemakings, DOE has conducted its walk-in refrigeration 
system engineering analysis using a single refrigerant--using R-404A 
for the June 2014 ECS final rule and using R-407A for the July 2017 ECS 
final rule. 79 FR 32050, 32073-32074 and 82 FR 31808, 31835-31836. 
However, for basic models certified with an AWEF value higher than the 
minimum standard in DOE's CCMS database, DOE observes that some 
refrigerants provide efficiency advantages over others for products 
with similar rated capacities. For instance, between certified 
capacities of 13,500 Btu/h and 16,500 Btu/h, one low-temperature 
condensing unit basic model was certified with a reported AWEF range 
from 3.5 to 3.87 and from 3.49 to 4.43 with R-407A and R-448A/R-449A, 
respectively.
    Issue 27: DOE requests comment and data to support whether it 
should include refrigerant as a design option in its engineering 
analysis for walk-in refrigeration systems. DOE also requests 
information on the availability and relative utility of R-452A, R-407C, 
and R-407F compared to R-407A and R-448A/R-449A for use in walk-in 
dedicated condensing units and single-package systems. Additionally, 
DOE is interested in understanding the availability and relative 
utility of R-450A, R-513A/R-513B, and R-515A compared to R-134A for 
wine cellar walk-in refrigeration systems. DOE is also interested in 
understanding what domestic and international activities may be driving 
trends in the market adoption of low GWP refrigerants.
    In addition to evaluating low GWP refrigerants, DOE is 
investigating the potential use of non-traditional refrigerants, such 
as hydrocarbon refrigerants.
    Issue 28: DOE requests information on the availability of specific 
non-traditional (e.g. hydrocarbon) refrigerants for use in dedicated 
condensing unit, unit cooler, single-package, and wine cellar walk-in 
refrigeration systems. DOE is interested in understanding what domestic 
and international activities may be driving trends in market adoption 
of non-traditional (e.g. hydrocarbon) refrigerants. DOE also seeks 
comment on whether and how the availability of higher-efficiency 
compressors might be impacted by the use of non-traditional (e.g. 
hydrocarbon) refrigerants. DOE requests information on whether charge 
limits or safety standards (e.g., standards issued by Underwriter's 
Laboratory) would restrict the use of non-traditional (e.g. 
hydrocarbon) refrigerants in walk-in refrigeration systems. Finally, 
DOE requests comment on any additional design changes or safety 
measures that may be necessary for WICFs to incorporate non-traditional 
(e.g. hydrocarbon) refrigerants.
    In its supporting analysis to the June 2014 ECS final rule, DOE 
evaluated evaporator coils with either 4 or 6 fins per inch for both 
low- and medium-temperature unit coolers.\34\ For the July 2017 ECS 
final rule, DOE's engineering analysis included evaporator coils with 4 
fins per inch for low-temperature and 6 fins per inch for medium-
temperature unit coolers.\35\ An evaluation of DOE's CCMS database \36\ 
indicates a minimum of 4 fins per inch and a maximum of 8 fins per inch 
for both low-temperature and medium-temperature units, with higher 
certified AWEF values for models with a higher number of fins per inch. 
Roughly 65 percent of low-temperature models have more than 4 fins per 
inch, while about 10 percent of medium-temperature models have more 
than 6 fins per inch.
---------------------------------------------------------------------------

    \34\ See Table 5.3.5 of the TSD for the June 2014 ECS final 
rule. Docket EERE-2008-BT-STD-0015-0131.
    \35\ See Table 5.3.2 of the TSD for the July 2017 ECS final 
rule. Docket EERE-2015-BT-STD-0016-0099.
    \36\ Please see footnote 15.
---------------------------------------------------------------------------

    Issue 29: DOE seeks comment on if 4 fins per inch and 6 fins per 
inch for low- and medium-temperature unit coolers, respectively, are 
still appropriate to use in its engineering analysis given the number 
of certified models at each operating temperature that do not meet 
these specifications--and if not, which fin configuration(s) should DOE 
use for its analysis?

[[Page 37699]]

    DOE also requests information and data on the potential impact on 
defrost frequency and/or daily energy use contributions for low-
temperature unit coolers with more than 4 fins per inch and for medium-
temperature unit coolers with more than 6 fins per inch used in high-
temperature freezer applications (i.e. freezers with an interior 
temperature range from 10 [deg]F to 32 [deg]F). Finally, DOE requests 
comment on whether the number of fins per inch would be different for 
medium-temperature unit coolers used for medium-temperature versus 
high-temperature freezer applications. If the number of fins per inch 
would differ, DOE seeks data to support a representative number of fins 
per inch for medium-temperature unit coolers used in high-temperature 
freezer applications.
b. Screening of Technology Options
    Table II.14 summarizes the refrigeration system technology options 
that DOE did not include in its analysis in the June 2014 ECS final 
rule and July 2017 ECS final rule, and the applicable screening 
criteria.

            Table II.14--Refrigeration Systems Technology Options Screened From the June 2014 ECS Final Rule and/or July 2017 ECS Final Rule
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                        EPCA criteria
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                      Practicability                        Adverse       Other reasons
                                                                     Technological    to manufacture,  Adverse  impact     impacts on        for not
                    Screened technology option                        feasibility      install, and      on  product       health and    considering the
                                                                                          service          utility           safety         technology
--------------------------------------------------------------------------------------------------------------------------------------------------------
Liquid suction heat exchangers....................................  ...............  ................  ...............  ...............             X *
Refrigeration system override.....................................  ...............  ................  ...............  ...............             X *
Economizer cooling................................................  ...............  ................  ...............  ...............             X *
Automatic evaporator fan shut-off.................................  ...............  ................  ...............  ...............             X *
Energy storage systems............................................               X   ................  ...............  ...............  ...............
High efficiency evaporator fan motor..............................               X   ................  ...............  ...............  ...............
3-Phase motors....................................................  ...............  ................               X   ...............  ...............
Improved evaporator coil..........................................  ...............  ................               X   ...............  ...............
Variable-capacity compressors.....................................  ...............  ................  ...............  ...............       X[dagger]
Adaptive defrost..................................................  ...............  ................  ...............  ...............             X *
On-cycle variable-speed evaporator fans...........................  ...............  ................  ...............  ...............             X *
Hot gas defrost...................................................  ...............  ................  ...............  ...............             X *
--------------------------------------------------------------------------------------------------------------------------------------------------------
* DOE screened out these technology options because they do not affect energy consumption as measured by the current DOE test procedure. (Docket EERE-
  2008-BT-STD-0015-0131, Section 4.2 at pp. 4-3 through 4-4; EERE-2015-BT-STD-0016-0099, Section 4.2 at pp. 4-2 through 4-4).
[dagger] DOE screened out variable-capacity compressors (a subset of higher-efficiency compressors) because the current DOE test procedure does not
  include a method for assessing variable-capacity dedicated condensing units tested without a matched unit cooler (see 10 CFR 431.304). 82 FR 31808,
  31839.

    Issue 30: DOE requests feedback on what impact, if any, DOE's 
screening criteria (technological feasibility; practicability to 
manufacture, install, and service; adverse impacts on product utility 
or product availability; adverse impacts on health or safety; and 
unique-pathway proprietary technologies) would have on each of the 
technology options listed in Table II.12 or Table II.13 of this 
document. Similarly, DOE seeks information regarding how these same 
criteria would affect any other technology options not already 
identified in this document with respect to their potential use in 
walk-in refrigeration systems.
    The current test procedure includes a method to address systems 
with adaptive defrost. Section 3.3.5 of appendix C to subpart R of 10 
CFR part 431. As provided in the DOE test procedure, adaptive defrost 
is not included in the determination of AWEF to demonstrate compliance 
but a manufacturer may voluntarily account for a unit's improved 
performance with adaptive defrost activated in its market 
representations. Id. As discussed in the June 2021 TP RFI, an adaptive 
system with a long period (i.e., when too much frost builds up on the 
coils) between defrosts may significantly affect the on-cycle 
performance of the refrigeration system; however, a system that 
defrosts frequently could increase defrost energy use. 86 FR 32332, 
32348. DOE recognizes the potential efficiency advantage offered by 
adaptive defrost and is considering how best to incorporate adaptive 
defrost into its analysis.
    In a future rulemaking, DOE may consider allowing walk-in 
refrigeration systems with adaptive defrost to continue to 
qualitatively represent improved efficiency performance solely for 
marketing purposes and not for demonstrating compliance with the 
current standards. Adaptive defrost could also be used to demonstrate 
compliance with energy conservation standards. DOE could also include 
adaptive defrost in its analysis for setting new energy conservation 
standards; however, DOE would need to determine whether adaptive 
defrost would be included in the engineering analysis for dedicated 
condensing unit or for unit coolers (since DOE's analysis is based on a 
single component).
    Issue 31: DOE requests stakeholder feedback on how to address 
adaptive defrost in a future rulemaking. Specifically, DOE is 
interested in data that support whether DOE should continue to screen 
adaptive defrost from its engineering analysis, and if not, DOE is 
interested in understanding whether adaptive defrost functionality and 
cost burden should be included in its analysis of dedicated condensing 
units or in its analysis of unit coolers. DOE additionally requests 
comment on how the screening results summarized in Table II.14 may have 
changed for adaptive defrost, such that the approaches used in the 
prior rulemaking analyses may no longer be appropriate.
    DOE removed hot gas defrost as a design option in its analysis for 
the July 2017 ECS final rule. 82 FR 31808, 31834. Instead, DOE assigned 
to hot gas defrost unit coolers the same default values for electric 
defrost heat and energy use calculations that the test procedure 
assigns to dedicated condensing units that are not matched with a unit 
cooler for testing (i.e., tested

[[Page 37700]]

alone). 81 FR 95758, 95774-95777, see also section 3.5 of appendix C to 
subpart R of 10 CFR part 431. In a test procedure final rule published 
on March 26, 2021 (``March 2021 TP final rule''), DOE updated the 
defrost energy use and thermal load equations for hot gas defrost unit 
coolers tested alone to provide a consistent performance evaluation 
between hot gas defrost and electric defrost unit coolers when tested 
alone. 86 FR 16027, 16030. However, this approach does not measure or 
account for actual hot gas defrost thermal load and energy use. 81 FR 
95758, 95774-95777.
    As discussed in the June 2021 TP RFI, defrost heat and energy 
values specific to hot gas defrost units are included in the most 
recent industry test method, ``2020 Standard for Performance Rating of 
Walk-In Coolers and Freezers,'' (``AHRI 1250-2020''). 86 FR 32332, 
32347. Similar to the current approach for adaptive defrost, DOE could 
allow walk-in refrigeration systems with hot gas defrost to 
qualitatively represent improved efficiency performance solely for 
marketing purposes and not for demonstrating compliance with the 
current standards. Hot gas defrost could also be used to demonstrate 
compliance with energy conservation standards. DOE could also include 
hot gas defrost as a design option in its analysis for setting new 
energy conservation standards.
    Issue 32: DOE requests stakeholder feedback on how to address hot 
gas defrost in a future rulemaking. Specifically, DOE is interested in 
data that support whether DOE should continue to screen hot gas defrost 
from its engineering analysis, and if not, DOE is interested in 
understanding whether hot gas defrost functionality and cost burden 
should be included in its analysis of dedicated condensing units or in 
its analysis of unit coolers. DOE additionally requests comment on how 
the screening results presented in Table II.14 of this document have 
changed for hot gas defrost, such that the approaches used in the prior 
rulemaking analyses may no longer be appropriate.
c. Representative Units
    In the June 2014 ECS final rule and July 2017 ECS final rule, DOE 
analyzed the representative refrigeration system capacities presented 
in Table II.15. 79 FR 32050, 37073 and 82 FR 31808, 31835. However, 
data retrieved from DOE's CCMS database \15\ indicates that:
    <bullet> For outdoor medium-temperature dedicated condensing units, 
39 percent of certified units have a nominal capacity greater than 
96,000 Btu/h and 19 percent of certified units have a capacity greater 
than 200,000 Btu/h;
    <bullet> For low-temperature unit coolers, 48 percent of certified 
units have a rated capacity of greater than 40,000 Btu/h and 19 percent 
are rated at greater than 100,000 Btu/h;
    <bullet> For medium-temperature unit coolers, 55 percent of 
certified units have a nominal capacity greater than 24,000 Btu/h, with 
16 percent rated at greater than 100,000 Btu/h.
    These data are based on a count of basic models submitted to the 
CCMS database and do not indicate the volume of shipments of each 
model.

 Table II.15--Representative Refrigeration System Units Evaluated in the June 2014 and July 2017 ECS Final Rules
----------------------------------------------------------------------------------------------------------------
                                          Representative
             Equipment class               unit capacity      Representative unit        Associated rulemaking
                                              (Btu/h)           compressor type
----------------------------------------------------------------------------------------------------------------
Dedicated Condensing, Medium, Indoor....           6,000  Hermetic..................  June 2014 ECS final rule.*
                                                   6,000  Semi-hermetic.............
                                                  18,000  Hermetic..................
                                                  18,000  Scroll....................
                                                  18,000  Semi-hermetic.............
                                                  54,000  Scroll....................
                                                  54,000  Semi-hermetic.............
                                                  96,000  Scroll....................
                                                  96,000  Semi-hermetic.............
Dedicated Condensing, Medium, Outdoor...           6,000  Hermetic..................
                                                   6,000  Semi-hermetic.............
                                                  18,000  Hermetic..................
                                                  18,000  Scroll....................
                                                  18,000  Semi-hermetic.............
                                                  54,000  Scroll....................
                                                  54,000  Semi-hermetic.............
                                                  96,000  Scroll....................
                                                  96,000  Semi-hermetic.............
Dedicated Condensing, Low, Indoor,                 6,000  Scroll....................  July 2017 ECS final
 <6,500 Btu/h.                                                                         rule.**
Dedicated Condensing, Low, Indoor,                 9,000  Scroll....................
 >=6,500 Btu/h.
                                                  25,000  Scroll....................
                                                  25,000  Semi-hermetic.............
                                                  54,000  Semi-hermetic.............
Dedicated Condensing, Low, Outdoor,                6,000  Scroll....................
 <6,500 Btu/h.
Dedicated Condensing, Low, Outdoor,                9,000  Scroll....................
 >=6,500 Btu/h.
                                                  25,000  Scroll....................
                                                  25,000  Semi-hermetic.............
                                                  54,000  Semi-hermetic.............
                                                  72,000  Semi-hermetic.............
Unit Cooler, Medium.....................           4,000  N/A.......................
                                                   9,000  N/A.......................
                                                  24,000  N/A.......................
Unit Cooler, Low, <15,500 Btu/h.........           4,000  N/A.......................
                                                   9,000  N/A.......................
Unit Cooler, Low, >=15,500 Btu/h........          18,000  N/A.......................

[[Page 37701]]

 
                                                  40,000  N/A.......................
----------------------------------------------------------------------------------------------------------------
* See section 5A.5 at pp. 5A-28 through 5A-45 of the TSD for the June 2014 ECS final rule, Docket EERE-2008-BT-
  STD-0015-0131.
** See section 5A.2 at pp. 5A-1 through 5A-18 of the TSD for the July 2017 ECS final rule, Docket EERE-2008-BT-
  STD-0015-0099.

    Issue 33: DOE seeks comment on whether the representative minimum 
and maximum capacities listed in Table II.15 of this document are 
appropriate for walk-ins of 3,000 square feet or less. Specifically, 
DOE is interested in whether the highest capacities listed for each 
equipment class in Table II.15 of this document appropriately represent 
walk-ins within the scope of DOE's energy conservation standards (and/
or sufficiently representative of models up to the largest capacities). 
If the highest capacities listed for each equipment class in Table 
II.15 of this document are not representative, DOE requests data and 
supporting information as to why they are not representative, and what 
appropriate maximum capacities for each equipment class would be.
    Issue 34: DOE seeks comment on the appropriateness of the 
compressor types associated with each representative unit. 
Specifically, DOE seeks data on the respective ranges of refrigeration 
system capacities for which each compressor type (scroll, hermetic, and 
semi-hermetic) may realistically be used. Further, DOE seeks comment on 
if there are refrigeration system capacity ranges for which multiple 
types of compressors may be used.
    DOE's initial research into single-package refrigeration systems 
indicates that capacities range between 1,900 Btu/h and 29,000 Btu/h, 
with most units less than 17,000 Btu/h. In order to conduct an 
engineering analysis for single-package refrigeration systems, DOE 
seeks information on the capacities of the most representative units on 
the market.
    Issue 35: DOE requests comment on appropriate representative 
capacities for single-package refrigeration systems. Specifically, DOE 
requests data on the availability and prevalence of single-package 
units sized between 17,000 Btu/h and 29,000 Btu/h, and whether DOE 
should consider including a representative single-packaged 
refrigeration system with capacity in this range.
    To conduct an engineering analysis for wine cellar refrigeration 
systems, DOE seeks information on the size and capacities of the most 
representative units on the market. DOE's initial research into wine 
cellar refrigeration systems indicates that the capacity for most 
single-package and matched-pair units ranges from 1,000 Btu/h to 18,000 
Btu/h, with very few units between 13,000 Btu/h and 18,000 Btu/hr. 
Additionally, DOE received information from AHRI in 2019 listing 
capacity, AWEF, condenser fan power, and compressor type for wine 
cellar refrigeration systems.\37\
---------------------------------------------------------------------------

    \37\ The AHRI Wine Cellar AWEF Technical Justification document 
containing the performance data of wine cellar refrigeration systems 
can be found at www.regulations.gov Docket No. EERE-2017-BT-STD-
0009-0011.
---------------------------------------------------------------------------

    Issue 36: DOE requests comment on if the capacity, AWEF, condenser 
fan power, and compressor types provided by AHRI are representative of 
the market for single-package and matched-pair wine cellar 
refrigeration systems. DOE also seeks information on the availability 
and prevalence of wine cellar refrigeration systems between 13,000 and 
18,000 Btu/h for walk-in wine cellars with a square footage of 3,000 
square feet or less.

D. Significant Savings of Energy

    In determining whether a proposed energy conservation standard is 
economically justified, DOE analyzes, among other things, the potential 
economic impact on consumers, manufacturers, and the Nation. DOE seeks 
comment on whether there are economic barriers to the adoption of more 
stringent energy conservation standards. DOE also seeks comment and 
data on any other aspects of its economic justification analysis from 
the June 2014 ECS final rule and July 2017 ECS final rule that may 
indicate whether a more stringent energy conservation standard would be 
economically justified or cost effective.
    While DOE is particularly interested in comment, information, and 
data on the following issues, this request for information is not 
strictly limited to them.
1. Markups Analysis--Distribution Channels
    DOE derives customer prices based on manufacturer markups, retailer 
markups, distributor markups, contractor markups (where appropriate), 
and sales taxes. In deriving these markups, DOE determines the major 
distribution channels for product sales, the markup associated with 
each party in each distribution channel, and the existence and 
magnitude of differences between markups for baseline products 
(``baseline markups'') and higher-efficiency products (``incremental 
markups''). The identified distribution channels (i.e., how the 
products are distributed from the manufacturer to the consumer) and 
estimated relative sales volumes through each channel are used in 
generating end-user price inputs for the life-cycle cost (``LCC'') 
analysis and national impact analysis (``NIA'').
    In the June 2014 ECS final rule and July 2017 ECS final rule, DOE 
defined the distribution channels for WICFs and estimated their 
respective shares of shipments as: (1) Direct to customer sales, 
through national accounts or contractors; (2) refrigeration wholesalers 
to consumers; (3) Original Equipment Manufacturers (``OEM'') to 
consumers--the OEM distribution channel primarily represents 
manufacturers of WICF refrigeration systems who may also install and 
sell entire WICF refrigeration units; (4) contractors who primarily 
install WICF envelope components (panels and doors); and (5) 
refrigeration equipment distributors of panels and non-display doors. 
WICF distribution channels evaluated in DOE's previous rulemakings are 
summarized in Table II.16.

[[Page 37702]]



                                       Table II.16--Distribution Channels
----------------------------------------------------------------------------------------------------------------
                                                                          Equipment type
                                                 ---------------------------------------------------------------
                          Distribution channel       Dedicated                    Panels and non-
                                                    condensing     Unit coolers    display doors   Display doors
                                                  equipment  (%)        (%)             (%)             (%)
----------------------------------------------------------------------------------------------------------------
1.....................  Direct (National                       3              45              49              30
                         Accounts).
2.....................  Refrigeration                         42              45  ..............  ..............
                         Wholesalers.
3.....................  OEM.....................              55              10  ..............              70
4.....................  General Contractor......  ..............  ..............               8  ..............
5.....................  Equipment Distributor...  ..............  ..............              43  ..............
                                                 ---------------------------------------------------------------
                           Total................             100             100             100             100
----------------------------------------------------------------------------------------------------------------

    Issue 37: DOE seeks comment on whether the distribution channels 
used in the June 2014 ECS final rule and July 2017 ECS final rule (as 
depicted in Table II.16) remain relevant today, and if not, DOE 
requests information on these channels as well as the existence of any 
additional channels that are used to distribute walk-in components into 
the market. Additionally, DOE requests comment on the appropriateness 
of these channels, and their respective fractions for the following 
equipment: display-panels, high-temperature freezers, single-package 
refrigeration systems, and wine cellars as described in sections II.A.1 
through II.A.4 of this document.
2. Lifetime Analysis
    The equipment lifetime is the age at which the equipment is retired 
from service. To reflect the uncertainty of equipment lifetimes the LCC 
analysis uses Weibull probability distributions for each equipment 
class. For the June 2014 ECS final rule and July 2017 ECS final rule 
DOE developed separate lifetime distributions for WICF envelope 
components and refrigeration system components. 79 FR 32050, 32086 and 
82 FR 31808, 31846. The average values of these distributions are shown 
in Table II.17.

         Table II.17--Estimated Average WICF Equipment Lifetimes
                                 [Years]
------------------------------------------------------------------------
                                                                Average
                          Component                             lifetime
                                                                (years)
------------------------------------------------------------------------
Refrigeration Systems (condensing systems and unit coolers)..       10.5
Non-display Doors (freight and passage doors)................          6
Display Doors................................................         12
Panels.......................................................         12
------------------------------------------------------------------------

    Issue 38: DOE seeks comment on its estimated equipment lifetime for 
WICF refrigeration system and envelope components. Specifically, DOE 
requests data on appropriate average lifetimes that DOE's analyses 
should use for: display-panels, high-temperature freezers, single-
package refrigeration systems, and wine cellars as described in 
sections II.A.1 through II.A.4 of this document.
3. Shipments Analysis
    DOE develops shipments forecasts of walk-ins to calculate the 
national impacts of potential amended energy conservation standards on 
energy consumption, net present value (``NPV''), and future 
manufacturer cash flows.\38\ DOE's shipments projections are based on 
available data broken out by equipment class, capacity, and efficiency. 
Current sales estimates allow for a more accurate model that captures 
recent trends in the market.
---------------------------------------------------------------------------

    \38\ DOE uses data on manufacturer shipments as a proxy for 
national sales, as aggregate data on sales are not readily available 
for DOE to examine. In general, one would expect a close 
correspondence between shipments and sales in light of their direct 
relationship with each other.
---------------------------------------------------------------------------

    The envelope component shipments model for panels and doors, and 
the refrigeration system shipments model for dedicated condensing 
systems and unit coolers, take an accounting approach, tracking market 
shares of each equipment class and the vintage of units in the existing 
stock over time. Stock accounting uses equipment shipments as inputs to 
estimate the age distribution of in-service equipment stocks for all 
the years covered under a potential revised standard. The age 
distribution of in-service equipment stocks is a key input to 
calculations of both the National Energy Savings (``NES'') and NPV of a 
potential new standard because operating costs for any year depend on 
the age distribution of the stock.
    DOE's shipments model of walk-in refrigeration systems and envelope 
components are driven by new purchases and stock replacements due to 
failures. Equipment failure rates are related to equipment lifetimes 
(see section II.D.2 of this document). In the analyses done for the 
June 2014 ECS final rule and July 2017 ECS final rule, DOE modeled 
projections for new equipment using the commercial building floor space 
growth rates of buildings classified as ``food sales,'' ``food 
service,'' and ``other'' from the Energy Information Administration's 
Annual Energy Outlook.\39\ In both the June 2014 ECS final rule and 
July 2017 ECS final rule DOE assumed that the share of shipments for 
each equipment class and capacity would remain constant over time. \40\ 
82 FR 31808, 31847.
---------------------------------------------------------------------------

    \39\ See chapter 9, section 9.2 of the June 2014 ECS final rule 
TSD, available at: www.regulations.gov/document/EERE-2008-BT-STD-0015-0131. See chapter 9, section 9.3 of the July 2017 ECS final 
rule TSD, available at: www.regulations.gov/document/EERE-2015-BT-STD-0016-0099. For more information see: www.eia.gov/outlooks/aeo/.
    \40\ The assumption that shipments for each capacity of each 
equipment class would remain constant over time were not explicitly 
stated in either the Notice or the TSD of the June 2014 ECS final 
rule. However, the results for the shipments analysis, where this 
assumption is applied, can be reviewed in the final rule National 
Impacts Analyses (NIA) models for both refrigeration systems, 
panels, and doors. For refrigeration systems: www.regulations.gov/document/EERE-2008-BT-STD-0015-0135. For panels and doors: 
www.regulations.gov/document/EERE-2008-BT-STD-0015-0134.
---------------------------------------------------------------------------

    Previously, complete historical shipments data for walk-ins could 
not be obtained from any single source. Therefore, in the June 2014 ECS 
final rule DOE used data from multiple sources to estimate historical 
shipments. 79 FR 32050, 32088. For the July 2017 ECS final rule, DOE 
continued with the same sources of shipments described in the NOPR 
published on September 13, 2016. 81 FR 62980, 63012.
    Issue 39: DOE requests comment on its assumption that the market 
share of shipments for each equipment class would remain constant over 
time.

[[Page 37703]]

a. Dedicated Condensing Systems and Unit Coolers
    For the July 2017 ECS final rule, DOE initialized its stock and 
shipments model for low-temperature dedicated condensing equipment and 
unit coolers based on shipments data provided by stakeholders.\41\ 82 
FR 31808, 31847. These data did not explicitly state the share of 
medium-temperature dedicated condensing units and were inferred from 
both the fraction of low-temperature dedicated condensing equipment for 
various applications, and from medium-temperature unit cooler 
shipments. Walk-in shipments data used in the July 2017 ECS final rule 
analysis are summarized in Table II.18.
---------------------------------------------------------------------------

    \41\ www.regulations.gov/document?D=EERE-2015-BT-STD-0016-0029, 
WICF Refrigeration Equipment Shipment Data--10212015.

                                        Table II.18--Estimated Condensing System and Unit Cooler Shipments, 2020
                                                                         [Units]
--------------------------------------------------------------------------------------------------------------------------------------------------------
                                                                                                  Equipment class
                                                         -----------------------------------------------------------------------------------------------
                                                              DC.L.I          DC.L.O           UC.L           DC.M.I          DC.M.O           UC.M
--------------------------------------------------------------------------------------------------------------------------------------------------------
Dedicated Condensing Unit Only..........................           3,202           4,075  ..............           6,459          11,481  ..............
Field Paired (Dedicated Condensing Systems and Unit               14,943          19,019  ..............          30,141          53,586  ..............
 Coolers)...............................................
Unit Coolers Only (connected to Dedicated Condensing      ..............  ..............           7,277  ..............  ..............          17,941
 Units).................................................
Unit Coolers Only (connected to Multiplexing Condensing   ..............  ..............          11,635  ..............  ..............          20,459
 Units).................................................
--------------------------------------------------------------------------------------------------------------------------------------------------------

    These data showed that:
    <bullet> 4 percent of shipments were manufacturer-matched dedicated 
condensing units and unit coolers (manufacturer matched-paired), and 
the remaining 96 percent were sold as individual dedicated condensing 
units or unit coolers that installers matched in the field (stand-
alone, and field-paired);
    <bullet> 82 percent of low-temperature unit coolers were paired 
with dedicated condensing systems, and the remaining 18 percent were 
paired with multiplex systems. With respect to medium-temperature unit 
coolers, 85 percent of these were paired with dedicated condensing 
systems while the remaining 15 percent were paired with multiplex 
systems; and
    <bullet> 46 percent of low-temperature dedicated condensing systems 
were installed indoors with the remaining 54 percent installed 
outdoors. Among medium-temperature dedicated condensing systems, 36 
percent of these were installed indoors with the remaining 64 percent 
installed outdoors.\42\
---------------------------------------------------------------------------

    \42\ See Chapter 9 of the TSD for the July 2017 ECS final rule. 
Docket EERE-2015-BT-STD-0016-0099.
---------------------------------------------------------------------------

    These shipments estimates are exclusive of single-package 
refrigeration systems, high-temperature freezers, and wine cellar 
refrigeration systems described in sections II.A.2 through II.A.4 of 
this document.
    Issue 40: DOE seeks input from stakeholders on whether the 
shipments shown for low-temperature dedicated condensing equipment and 
unit coolers are still relevant. Further, DOE seeks data on the annual 
shipments of low-temperature single-package refrigeration systems (see 
section II.A.3 of this document) and the distribution of rated 
capacities as shown in Table II.15 of this document.
    Issue 41: DOE seeks input from stakeholders on whether the 
shipments shown for medium-temperature condensing equipment and unit 
coolers reflect the state of the current market.
    Issue 42: DOE seeks data on the annual shipments of medium-
temperature single-package refrigeration systems (see section II.A.3 of 
this document), high-temperature freezers (see section II.A.2 of this 
document) and wine cellar refrigeration systems (see section II.A.4 of 
this document) and the distribution of rated capacities of each (Btu/
h). DOE also seeks data on the fraction of high-temperature freezers 
and wine cellar refrigeration systems that are sold as single-package, 
manufacturer matched-pair or split systems. Additionally, DOE requests 
data on the relative market size of refrigeration systems used in high 
temperature freezers compared to the refrigeration system market sizes 
for cooler applications (i.e., temperature greater than 32 [deg]F) and 
low-temperature (e.g., less than or equal to -10 [deg]F) freezer 
applications.
b. Doors and Panels
    For the July 2014 ECS final rule, DOE initialized its stock and 
shipments model for panels and doors based on the number of complete 
WICF units per unit of floor space area, per building of a given type 
and size having any WICF unit. These data were derived from the 
Commercial Buildings Energy Consumption Survey (``CBECS'') 1999 \43\ 
and CBECS 2003.<SUP>44 45</SUP>
---------------------------------------------------------------------------

    \43\ U.S. Department of Energy--Energy Information 
Administration. Commercial Buildings Energy Consumption Survey 1999. 
Washington, DC.
    \44\ U.S. Department of Energy--Energy Information 
Administration. Commercial Buildings Energy Consumption Survey 2003. 
Washington, DC.
    \45\ See Chapter 9 TSD for the June 2014 ECS final rule. Docket 
EERE-2008-BT-STD-0015-0131.
---------------------------------------------------------------------------

    These data show that 70 percent of panel shipments are medium-
temperature, 23 percent are low-temperature wall panels, and the 
remaining 7 percent are low-temperature floor panels (in terms of ft\2\ 
shipped). DOE's forecasted shipments for WICF panels in 2020 are shown 
in Table II.19 of this document. For the June 2014 ECS final rule, DOE 
did not include panels and non-display doors that were installed 
outdoors its analysis.

              Table II.19--Estimated Panel Shipments, 2020
                              [Million ft2]
------------------------------------------------------------------------
                                                             Shipments
              Utility                    Temperature       (million ft2)
 
------------------------------------------------------------------------
Wall Panels.......................  Medium..............              74

[[Page 37704]]

 
Wall Panels.......................  Low.................              27
Floor Panels......................  Low.................               8
------------------------------------------------------------------------

    For display and non-display (freight and passage) doors, the CBECS 
data show that:
    <bullet> 92 percent of display doors shipments were medium-
temperature with low-temperature making up the remaining 8 percent;
    <bullet> 67 percent of passage doors shipments were medium-
temperature and 33 percent were low-temperature; and
    <bullet> 65 percent of freight doors shipments were medium-
temperature and 35 percent were low-temperature.
    DOE's forecasted shipments for WICF doors in 2020 are shown in 
Table II.20. For the June 2014 ECS final rule DOE assumed that all 
doors were installed indoors.

               Table II.20--Estimated Door Shipments, 2020
                                 [Units]
------------------------------------------------------------------------
                                                             Shipments
              Utility                    Temperature          (units)
------------------------------------------------------------------------
Display Door......................  Medium..............         325,869
Display Door......................  Low.................          26,751
Passage Door......................  Medium..............         328,103
Passage Door......................  Low.................         161,848
Freight Door......................  Medium..............          19,477
Freight Door......................  Low.................          10,529
------------------------------------------------------------------------

    These shipments estimates are exclusive of display panels described 
in section II.A.1 of this document.
    Issue 43: DOE requests data on the fraction of low-temperature and 
medium-temperature panels that are installed outdoors versus indoors. 
Additionally, DOE requests data on the fraction of low-temperature and 
medium-temperature freight and passage doors that are installed 
outdoors versus indoors.
    Issue 44: DOE seeks input from stakeholders on whether the 
shipments shown for panels and doors reflect the state of the current 
market. Further, DOE seeks data on the annual shipments, in terms of 
units shipped, of low-temperature and medium-temperature display panels 
described in section II.A.1 of this document.
    Issue 45: DOE also requests specific information on high-humidity 
medium-temperature display door shipments (see section II.C.1.a of this 
document) and their fraction of annual display door shipments.

III. Submission of Comments

    DOE invites all interested parties to submit in writing by the date 
under the DATES heading, comments and information on matters addressed 
in this notification and on other matters relevant to DOE's early 
assessment of whether more-stringent energy conservation standards are 
warranted for walk-in coolers and freezers.
    Submitting comments via www.regulations.gov. The 
www.regulations.gov web page requires you to provide your name and 
contact information. Your contact information will be viewable to DOE 
Building Technologies staff only. Your contact information will not be 
publicly viewable except for your first and last names, organization 
name (if any), and submitter representative name (if any). If your 
comment is not processed properly because of technical difficulties, 
DOE will use this information to contact you. If DOE cannot read your 
comment due to technical difficulties and cannot contact you for 
clarification, DOE may not be able to consider your comment.
    However, your contact information will be publicly viewable if you 
include it in the comment or in any documents attached to your comment. 
Any information that you do not want to be publicly viewable should not 
be included in your comment, nor in any document attached to your 
comment. If this instruction is followed, persons viewing comments will 
see only first and last names, organization names, correspondence 
containing comments, and any documents submitted with the comments.
    Do not submit to www.regulations.gov information for which 
disclosure is restricted by statute, such as trade secrets and 
commercial or financial information (hereinafter referred to as 
Confidential Business Information (``CBI'')). Comments submitted 
through www.regulations.gov cannot be claimed as CBI. Comments received 
through the website will waive any CBI claims for the information 
submitted. For information on submitting CBI, see the Confidential 
Business Information section.
    DOE processes submissions made through www.regulations.gov before 
posting. Normally, comments will be posted within a few days of being 
submitted. However, if large volumes of comments are being processed 
simultaneously, your comment may not be viewable for up to several 
weeks. Please keep the comment tracking number that www.regulations.gov 
provides after you have successfully uploaded your comment.
    Submitting comments via email. Comments and documents submitted via 
email also will be posted to www.regulations.gov. If you do not want 
your personal contact information to be publicly viewable, do not 
include it in your comment or any accompanying documents. Instead, 
provide your contact information in a cover letter. Include your first 
and last names, email address, telephone number, and optional mailing 
address. The cover letter will not be publicly viewable as

[[Page 37705]]

long as it does not include any comments.
    Include contact information each time you submit comments, data, 
documents, and other information to DOE. Faxes will not be accepted.
    Comments, data, and other information submitted to DOE 
electronically should be provided in PDF (preferred), Microsoft Word or 
Excel, WordPerfect, or text (ASCII) file format. Provide documents that 
are not secured, written in English, and free of any defects or 
viruses. Documents should not contain special characters or any form of 
encryption and, if possible, they should carry the electronic signature 
of the author.
    Campaign form letters. Please submit campaign form letters by the 
originating organization in batches of between 50 to 500 form letters 
per PDF or as one form letter with a list of supporters' names compiled 
into one or more PDFs. This reduces comment processing and posting 
time.
    Confidential Business Information. Pursuant to 10 CFR 1004.11, any 
person submitting information that he or she believes to be 
confidential and exempt by law from public disclosure should submit via 
email two well-marked copies: One copy of the document marked 
``confidential'' including all the information believed to be 
confidential, and one copy of the document marked ``non-confidential'' 
with the information believed to be confidential deleted. DOE will make 
its own determination about the confidential status of the information 
and treat it according to its determination.
    It is DOE's policy that all comments may be included in the public 
docket, without change and as received, including any personal 
information provided in the comments (except information deemed to be 
exempt from public disclosure).
    DOE considers public participation to be a very important part of 
the process for developing test procedures and energy conservation 
standards. DOE actively encourages the participation and interaction of 
the public during the comment period in each stage of this process. 
Interactions with and between members of the public provide a balanced 
discussion of the issues and assist DOE in the process. Anyone who 
wishes to be added to the DOE mailing list to receive future notices 
and information about this process should contact Appliance and 
Equipment Standards Program staff at (202) 287-1445 or via email at 
<a href="/cdn-cgi/l/email-protection#ca8bbabaa6a3aba4a9af99beaba4aeabb8aeb99bbfafb9bea3a5a4b98aafafe4aea5afe4ada5bc"><span class="__cf_email__" data-cfemail="39784949555058575a5c6a4d58575d584b5d4a684c5c4a4d5056574a795c5c175d565c175e564f">[email protected]</span></a>.

IV. Issues on Which DOE Seeks Comment

    Although DOE welcomes comments on any aspect of this proposal, DOE 
is particularly interested in receiving comments and views of 
interested parties concerning the following issues:
    Issue 1: DOE seeks information regarding the thermal transmission 
through display panels and design characteristics which would affect 
the thermal transmission, specifically, ``glass pack'' design and frame 
design. DOE also seeks information regarding the amount of direct 
electrical energy consumption of electricity-consuming devices sited on 
or within display panels, including the amount of anti-sweat heat 
required, if any. DOE additionally requests information on any specific 
design or use characteristics differentiating display panels from 
display doors.
    Issue 2: DOE requests comment on (1) whether there are medium-
temperature refrigeration system models that are used exclusively in 
high temperature freezers, and (2) if a medium-temperature 
refrigeration system is efficient for cooler applications, will it also 
be efficient for use in high-temperature freezer applications. To the 
extent available, DOE requests data on dedicated condensing unit energy 
efficiency ratio (``EER'') at both high-temperature freezer and medium-
temperature refrigeration operation.
    Issue 3: DOE requests data and information on the impact of single-
package system design limitations on efficiency and how single-package 
systems differ from split systems. DOE additionally requests 
information showing the trend of efficiency as a function of capacity 
for single-package refrigeration systems.
    Issue 4: DOE seeks information on how trends in wine cellar 
installations (e.g., commercial vs. residential, square footage, etc.) 
are expected to impact the type of refrigeration system (i.e., single-
package, matched-pair, dedicated condensing unit, or unit cooler 
system) used in wine cellars over the next 5 to 10 years. Additionally, 
DOE requests information and data on the extent to which capacity may 
impact the efficiency of wine cellar refrigeration systems.
    Issue 5: DOE seeks input and data as to the daily run-time hours, 
sizing practice, and ambient conditions for the following: single-
package refrigeration systems, high-temperature freezers, and wine 
cellars described in sections II.A.2 through II.A.4 of this document. 
DOE also requests information and data regarding any other aspects of 
the operation of such equipment that would influence run-time hours.
    Issue 6: DOE seeks input and data on the appropriate PTO values for 
display doors that would be exposed to higher levels of humidity. 
Specifically, DOE requests information on high-humidity walk-in cooler 
doors, including the range of typical installation conditions (e.g., 
relative humidity throughout the year in store). DOE also requests data 
on the average amount of time per day or per year that anti-sweat 
heaters with timers, control systems, or demand-based controls are 
operating at their full power and partial power (if applicable) for 
walk-in cooler display doors marketed for high-humidity applications.
    Issue 7: DOE seeks input on whether the combined safety and 
capacity mismatch oversizing factors for adjusting daily nominal run-
time hours relied on in the June 2014 ECS final rule and the July 2017 
ECS final rule are appropriate for single-package refrigeration 
systems, high-temperature freezers, and wine cellars as described in 
sections II.A.2 through II.A.4 of this document. If different factors 
would be appropriate for such equipment, DOE requests data in support 
of alternate assumptions.
    Issue 8: DOE seeks data and information regarding the current, and 
projected future market shares of WICF equipment by efficiency level 
(e.g., expressed in terms of increments of 10 percent improvement in 
AWEF, R-values, and kWh/day for refrigeration systems, panels, and 
doors, respectively, above or below the existing standards in 10 CFR 
431.306) to establish market trends in equipment efficiency over time. 
DOE also seeks information on how the current regulatory environment 
has affected the market share of WICF equipment by efficiency rating.
    Issue 9: DOE seeks information on how the physical construction of 
a display door, including the glass pack and the frame, impact the 
amount of anti-sweat heater wire power needed to prevent condensation 
accumulating on any part of the door. Specifically, DOE seeks 
quantitative data, if available, on the change in anti-sweat heater 
power (1) with a specific change in door frame design but no change in 
glass pack design, (2) with a specific change in glass pack design but 
no change in door frame design, and/or (3) with specific changes to the 
entire assembly. If there are specific design choices which are more 
costly but result in less or no anti-sweat heat, DOE requests cost data 
based on the capability of the door to prevent condensation from 
forming and the respective design options chosen.

[[Page 37706]]

DOE also requests comment on any other considerations which may impact 
the use and power of anti-sweat heaters.
    Issue 10: DOE seeks specific data and information on the 
correlation between relative humidity conditions at installation and 
the anti-sweat heater power needed to prevent condensation from 
accumulating on a walk-in door.
    Issue 11: DOE requests comment on the differences in design, 
typical conditions, and usage of a walk-in display door as compared to 
a display door for commercial refrigeration equipment which result in 
commercial refrigeration equipment door designs with no anti-sweat 
heaters.
    Issue 12: DOE seeks specific data and information on how the 
physical construction of both passage and freight doors impact the 
amount of anti-sweat heater wire power needed to prevent condensation 
accumulation on any part of the door. DOE requests specific comment on 
any technologies that may reduce or eliminate the need for anti-sweat 
heat on passage or freight doors. DOE also requests door design 
information and data that explain why many passage and freight doors 
are able to perform without any anti-sweat heater power in the field 
but some doors, specifically low-temperature passage and freight doors, 
still require anti-sweat power that is greater than that required for 
display doors to prevent condensation accumulation.
    Issue 13: DOE requests comment on the prevalence of vacuum-
insulated glass for walk-in doors and whether other manufacturers are 
considering adopting this technology. DOE requests specific feedback on 
any obstacles or concerns (e.g., patents, proprietary use, durability, 
practicability to manufacture, etc.) which would prevent manufacturers 
from using vacuum-insulated glass in walk-in doors. DOE also requests 
cost data for implementing vacuum-insulated glass in walk-in display 
doors.
    Issue 14: DOE requests feedback on what impact, if any, DOE's 
screening criteria (technological feasibility; practicability to 
manufacture, install, and service; adverse impacts on product utility 
or product availability; adverse impacts on health or safety; and 
unique-pathway proprietary technologies) would have on each of the 
technology options listed in Table II.6, Table II.7, and Table II.8 of 
this document. DOE also seeks information regarding how these same 
criteria would affect any other technology options not already 
identified in this document with respect to their potential use in 
walk-in doors and panels.
    Issue 15: DOE requests comment on whether 6 inches is an 
appropriate upper limit for screening out insulation thickness for 
panels and doors. For manufacturers that produce and certify panels 
with insulation thicknesses exceeding 6 inches, DOE requests feedback 
on what manufacturing investments have been made to do so. For 
manufacturers that do not produce panels with insulation thicknesses 
exceeding 6 inches, DOE requests feedback on the obstacles preventing 
them from increasing panel thickness.
    Issue 16: DOE requests feedback on the representative units for 
display doors used for the 2014 ECS final rule engineering analysis and 
whether multi-door configurations should be included as representative 
units. If so, DOE seeks comment on panel size and the number of panels 
that would be most representative for multi-door configurations. 
Additionally, DOE seeks specific data on the appropriate number of door 
openings and door sizes to consider and the additional electrical 
component power (e.g., anti-sweat heater power, lighting, etc.) 
required for each additional door opening. DOE is also interested in 
any other differences between single-door and multi-door configurations 
that would impact energy use.
    Issue 17: DOE seeks comment on the appropriateness of the 
representative units chosen for the previous analysis of passage and 
freight doors. DOE requests specific feedback on what the minimum and 
maximum sizes of both passage and freight doors are and if there are 
other attributes besides size which differentiate passage doors from 
freight doors and vice versa.
    Issue 18: DOE seeks comment on the prevalence of motorized door 
openers for both display and non-display doors. DOE requests specific 
feedback on the prevalence of motorized door openers by equipment 
class, the minimum door size that might have a motorized door opener, 
the percentage of doors sold which typically include a motorized door 
opener, and any data relating power of a motorized door opener to door 
size.
    Issue 19: DOE requests comment on whether there are technology 
options or other design features that would be unique to high-
temperature freezer refrigeration systems (i.e., medium-temperature 
systems operating at a temperature between 10 [deg]F to 32 [deg]F) as 
compared to technology options or design features for medium-
temperature refrigeration systems operating at above-freezing (cooler) 
temperatures. If high-temperature freezer refrigeration systems have 
certain unique features, DOE seeks information on those features and 
how they impact refrigeration system performance.
    Issue 20: DOE requests comment on which of the technology options 
listed in Table II.12 and Table II.13 of this document are available 
and used in single-package refrigeration systems. DOE also requests 
comment on whether there are other technologies that apply to single-
package refrigeration systems not mentioned in Table II.12 or Table 
II.13 of this document. Additionally, DOE requests comment on which 
technology options are feasible for dedicated condensing systems and 
unit coolers but may not be feasible for single-packaged refrigeration 
systems due to structural design constraints.
    Issue 21: DOE requests comment on which of the technology options 
listed in Table II.12 and Table II.13 of this document are available 
and used in wine cellar refrigeration systems. DOE also seeks 
information on whether there are additional technologies that apply to 
wine cellar refrigeration systems that are not mentioned in Table II.12 
or Table II.13 of this document. Additionally, DOE requests comment on 
the specific design constraints for wine cellar refrigeration systems 
and how these constraints may impact the use of certain technology 
options.
    Issue 22: DOE seeks information on the availability of multiple-
capacity or variable-capacity compressors in the current market. DOE is 
also interested in any end-user requirements that may restrict the use 
of, or reduce the potential benefits of, multi- or variable-capacity 
compressors in the field.
    Issue 23: DOE requests comment on the relative efficiency 
difference between scroll and semi-hermetic compressors in the range of 
capacities in which both are available. DOE also requests comment on 
other design parameters that would lead a manufacturer to select a 
certain compressor design over another and would represent potential 
utility differences of different compressor designs, specifically, (1) 
compressor weight relative to the final equipment weight and its impact 
on equipment shipping, installation, and end-use; (2) compressor 
durability, equipment warranty, and equipment lifetime; and (3) any 
other relevant differences.
    Issue 24: DOE seeks information on the availability and 
efficiencies of single-speed compressors (e.g., scroll compressors, 
rotary compressors, semi-hermetic compressors) that were not available 
or were not considered in the analysis during the rulemaking finalized 
in 2017. Additionally, DOE is interested in understanding the 
availability of

[[Page 37707]]

rotary compressors for use in single-package and wine cellar 
refrigeration systems.
    Issue 25: DOE seeks comment on the prevalence of the use of 
crankcase heater controls for walk-in refrigeration systems. 
Additionally, DOE requests information on what type of crankcase heater 
controls are considered viable, and what application circumstances 
would make certain control approaches inappropriate e.g., by 
unacceptably increasing the chance of compressor failure.
    Issue 26: DOE seeks information on the potential for improved 
thermal insulation and sealing of air leaks to improve the efficiency 
of single-package refrigeration systems. Specifically, DOE is 
interested in data on the range of typical insulation thickness used in 
single-package systems to insulate the indoor portion, in addition to 
the insulation materials that are typically used. Additionally, DOE 
requests information on the processes and materials that manufacturers 
utilize to ensure airtight enclosures. DOE is also interested in 
understanding the quality control processes manufacturers have in place 
to ensure that airtight units are released to the market.
    Issue 27: DOE requests comment and data to support whether it 
should include refrigerant as a design option in its engineering 
analysis for walk-in refrigeration systems. DOE also requests 
information on the availability and relative utility of R-452A, R-407C, 
and R-407F compared to R-407A and R-448A/R-449A for use in walk-in 
dedicated condensing units and single-package systems. Additionally, 
DOE is interested in understanding the availability and relative 
utility of R-450A, R-513A/R-513B, and R-515A compared to R-134A for 
wine cellar walk-in refrigeration systems. DOE is also interested in 
understanding what domestic and international activities may be driving 
trends in the market adoption of low GWP refrigerants.
    Issue 28: DOE requests information on the availability of specific 
non-traditional (e.g., hydrocarbon) refrigerants for use in dedicated 
condensing unit, unit cooler, single-package, and wine cellar walk-in 
refrigeration systems. DOE is interested in understanding what domestic 
and international activities may be driving trends in market adoption 
of non-traditional (e.g., hydrocarbon) refrigerants. DOE also seeks 
comment on whether and how the availability of higher-efficiency 
compressors might be impacted by the use of non-traditional (e.g., 
hydrocarbon) refrigerants. DOE requests information on whether charge 
limits or safety standards (e.g., standards issued by Underwriter's 
Laboratory) would restrict the use of non-traditional (e.g., 
hydrocarbon) refrigerants in walk-in refrigeration systems. Finally, 
DOE requests comment on any additional design changes or safety 
measures that may be necessary for WICFs to incorporate non-traditional 
(e.g., hydrocarbon) refrigerants.
    Issue 29: DOE seeks comment on if 4 fins per inch and 6 fins per 
inch for low- and medium-temperature unit coolers, respectively, are 
still appropriate to use in its engineering analysis given the number 
of certified models at each operating temperature that do not meet 
these specifications--and if not, which fin configuration(s) should DOE 
use for its analysis? DOE also requests information and data on the 
potential impact on defrost frequency and/or daily energy use 
contributions for low-temperature unit coolers with more than 4 fins 
per inch and for medium-temperature unit coolers with more than 6 fins 
per inch used in high-temperature freezer applications (i.e., freezers 
with an interior temperature range from 10 [deg]F to 32 [deg]F). 
Finally, DOE requests comment on whether the number of fins per inch 
would be different for medium-temperature unit coolers used for medium-
temperature versus high-temperature freezer applications. If the number 
of fins per inch would differ, DOE seeks data to support a 
representative number of fins per inch for medium-temperature unit 
coolers used in high-temperature freezer applications.
    Issue 30: DOE requests feedback on what impact, if any, DOE's 
screening criteria (technological feasibility; practicability to 
manufacture, install, and service; adverse impacts on product utility 
or product availability; adverse impacts on health or safety; and 
unique-pathway proprietary technologies) would have on each of the 
technology options listed in Table II.12 or Table II.13 of this 
document. Similarly, DOE seeks information regarding how these same 
criteria would affect any other technology options not already 
identified in this document with respect to their potential use in 
walk-in refrigeration systems.
    Issue 31: DOE requests stakeholder feedback on how to address 
adaptive defrost in a future rulemaking. Specifically, DOE is 
interested in data that support whether DOE should continue to screen 
adaptive defrost from its engineering analysis, and if not, DOE is 
interested in understanding whether adaptive defrost functionality and 
cost burden should be included in its analysis of dedicated condensing 
units or in its analysis of unit coolers. DOE additionally requests 
comment on how the screening results summarized in Table II.14 may have 
changed for adaptive defrost, such that the approaches used in the 
prior rulemaking analyses may no longer be appropriate.
    Issue 32: DOE requests stakeholder feedback on how to address hot 
gas defrost in a future rulemaking. Specifically, DOE is interested in 
data that support whether DOE should continue to screen hot gas defrost 
from its engineering analysis, and if not, DOE is interested in 
understanding whether hot gas defrost functionality and cost burden 
should be included in its analysis of dedicated condensing units or in 
its analysis of unit coolers. DOE additionally requests comment on how 
the screening results presented in Table II.14 of this document have 
changed for hot gas defrost, such that the approaches used in the prior 
rulemaking analyses may no longer be appropriate.
    Issue 33: DOE seeks comment on whether the representative minimum 
and maximum capacities listed in Table II.15 of this document are 
appropriate for walk-ins of 3,000 square feet or less. Specifically, 
DOE is interested in whether the highest capacities listed for each 
equipment class in Table II.15 of this document appropriately represent 
walk-ins within the scope of DOE's energy conservation standards (and/
or sufficiently representative of models up to the largest capacities). 
If the highest capacities listed for each equipment class in Table 
II.15 of this document are not representative, DOE requests data and 
supporting information as to why they are not representative, and what 
appropriate maximum capacities for each equipment class would be.
    Issue 34: DOE seeks comment on the appropriateness of the 
compressor types associated with each representative unit. 
Specifically, DOE seeks data on the respective ranges of refrigeration 
system capacities for which each compressor type (scroll, hermetic, and 
semi-hermetic) may realistically be used. Further, DOE seeks comment on 
if there are refrigeration system capacity ranges for which multiple 
types of compressors may be used.
    Issue 35: DOE requests comment on appropriate representative 
capacities for single-package refrigeration systems. Specifically, DOE 
requests data on the availability and prevalence of single-package 
units sized between 17,000 Btu/h and 29,000 Btu/h, and whether DOE 
should consider including a representative single-packaged 
refrigeration system with capacity in this range.

[[Page 37708]]

    Issue 36: DOE requests comment on if the capacity, AWEF, condenser 
fan power, and compressor types provided by AHRI are representative of 
the market for single-package and matched-pair wine cellar 
refrigeration systems. DOE also seeks information on the availability 
and prevalence of wine cellar refrigeration systems between 13,000 and 
18,000 Btu/h for walk-in wine cellars with a square footage of 3,000 
square feet or less.
    Issue 37: DOE seeks comment on whether the distribution channels 
used in the June 2014 ECS final rule and July 2017 ECS final rule (as 
depicted in Table II.16) remain relevant today, and if not, DOE 
requests information on these channels as well as the existence of any 
additional channels that are used to distribute walk-in components into 
the market. Additionally, DOE requests comment on the appropriateness 
of these channels, and their respective fractions for the following 
equipment: display-panels, high-temperature freezers, single-package 
refrigeration systems, and wine cellars as described in sections II.A.1 
through II.A.4 of this document.
    Issue 38: DOE seeks comment on its estimated equipment lifetime for 
WICF refrigeration system and envelope components. Specifically, DOE 
requests data on appropriate average lifetimes that DOE's analyses 
should use for: Display-panels, high-temperature freezers, single-
package refrigeration systems, and wine cellars as described in 
sections II.A.1 through II.A.4 of this document.
    Issue 39: DOE requests comment on its assumption that the market 
share of shipments for each equipment class would remain constant over 
time.
    Issue 40: DOE seeks input from stakeholders on whether the 
shipments shown for low-temperature dedicated condensing equipment and 
unit coolers are still relevant. Further, DOE seeks data on the annual 
shipments of low-temperature single-package refrigeration systems (see 
section II.A.3 of this document) and the distribution of rated 
capacities as shown in Table II.15 of this document.
    Issue 41: DOE seeks input from stakeholders on whether the 
shipments shown for medium-temperature condensing equipment and unit 
coolers reflect the state of the current market.
    Issue 42: DOE seeks data on the annual shipments of medium-
temperature single-package refrigeration systems (see section II.A.3 of 
this document), high-temperature freezers (see section II.A.2 of this 
document) and wine cellar refrigeration systems (see section II.A.4 of 
this document) and the distribution of rated capacities of each (Btu/
h). DOE also seeks data on the fraction of high-temperature freezers 
and wine cellar refrigeration systems that are sold as single-package, 
manufacturer matched-pair or split systems. Additionally, DOE requests 
data on the relative market size of refrigeration systems used in high 
temperature freezers compared to the refrigeration system market sizes 
for cooler applications (i.e., temperature greater than 32 [deg]F) and 
low-temperature (e.g., less than or equal to -10 [deg]F) freezer 
applications.
    Issue 43: DOE requests data on the fraction of low-temperature and 
medium-temperature panels that are installed outdoors versus indoors. 
Additionally, DOE requests data on the fraction of low-temperature and 
medium-temperature freight and passage doors that are installed 
outdoors versus indoors.
    Issue 44: DOE seeks input from stakeholders on whether the 
shipments shown for panels and doors reflect the state of the current 
market. Further, DOE seeks data on the annual shipments, in terms of 
units shipped, of low-temperature and medium-temperature display panels 
described in section II.A.1 of this document.
    Issue 45: DOE also requests specific information on high-humidity 
medium-temperature display door shipments (see section II.C.1.a of this 
document) and their fraction of annual display door shipments.

Signing Authority

    This document of the Department of Energy was signed on July 7, 
2021, by Kelly Speakes-Backman, Principal Deputy Assistant Secretary 
and Acting Assistant Secretary for Energy Efficiency and Renewable 
Energy, pursuant to delegated authority from the Secretary of Energy. 
That document with the original signature and date is maintained by 
DOE. For administrative purposes only, and in compliance with 
requirements of the Office of the Federal Register, the undersigned DOE 
Federal Register Liaison Officer has been authorized to sign and submit 
the document in electronic format for publication, as an official 
document of the Department of Energy. This administrative process in no 
way alters the legal effect of this document upon publication in the 
Federal Register.

    Signed in Washington, DC, on July 8, 2021.
Treena V. Garrett,
Federal Register Liaison Officer, U.S. Department of Energy.
[FR Doc. 2021-14902 Filed 7-15-21; 8:45 am]
BILLING CODE 6450-01-P


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