Energy Conservation Program for Certain Industrial Equipment:
Federal Register Volume 76, Number 87 (Thursday, May 5, 2011)
Proposed Rules
Pages 25622-25648
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
FR Doc No: 2011-10877
DEPARTMENT OF ENERGY 10 CFR Part 431
Docket No. EERE-2011-BT-STD-0029
RIN 1904-AC47
Energy Conservation Program for Certain Industrial Equipment:
Energy Conservation Standards for Commercial Heating, Air-Conditioning, and Water-Heating Equipment
AGENCY: Office of Energy Efficiency and Renewable Energy, Department of
Energy.
ACTION: Notice of data availability and request for public comment.
SUMMARY: The Energy Policy and Conservation Act of 1975 (EPCA), as amended, directs the U.S. Department of Energy (DOE) to establish energy conservation standards for certain commercial and industrial equipment, including commercial heating, air-conditioning, and water- heating products. Of particular relevance here, the statute also requires that each time the corresponding consensus standard--the
American Society of Heating, Refrigerating and Air-Conditioning
Engineers, Inc. (ASHRAE)/Illuminating Engineering Society of North
America (IESNA) Standard 90.1--is amended by the industry, DOE must assess whether there is a need to update the uniform national energy conservation standards for the same equipment covered under EPCA.
ASHRAE officially released an amended version of this industry standard
(ASHRAE 90.1-2010) on October 29, 2010, thereby triggering DOE's related obligations under EPCA. In addition, the Energy Independence and Security Act of 2007 (EISA 2007) amended EPCA to require DOE to review the most recently published ASHRAE/IES Standard 90.1 with respect to single-package vertical air conditioners and single-package vertical heat pumps in accordance with the procedures established for reviewing the energy conservation standards for other
Page 25623
ASHRAE products. As a first step in meeting these statutory requirements, today's notice of data availability (NODA) discusses the results of DOE's analysis of the energy savings potential of amended energy conservation standards for certain types of commercial equipment covered by ASHRAE Standard 90.1, including single-package vertical air conditioners and single-package vertical heat pumps. The energy savings potentials are based upon either the efficiency levels specified in the amended industry standard (i.e., ASHRAE Standard 90.1-2010) or more stringent levels that would result in significant additional conservation of energy and are technologically feasible and economically justified. DOE is publishing this NODA to: Announce the results and preliminary conclusions of DOE's analysis of potential energy savings associated with amended standards for this equipment, and request public comment on this analysis, as well as the submission of data and other relevant information.
DATES: DOE will accept comments, data, and information regarding this
NODA submitted no later than June 6, 2011. See section IV, ``Public
Participation,'' of this notice for details.
ADDRESSES: Any comments submitted must identify the NODA for ASHRAE
Products and provide the docket number EERE-2011-BT-STD-0029 and/or
Regulatory Information Number (RIN) 1904-AC47. Comments may be submitted using any of the following methods: 1. Federal eRulemaking Portal: http://www.regulations.gov. Follow the instructions for submitting comments. 2. E-mail: ASHRAE90.1-2011-STD-0029@ee.doe.gov. Include the Docket
Number EERE-2011-BT-STD-0029 and/or RIN number 1904-AC47 in the subject line of the message. 3. Postal Mail: Ms. Brenda Edwards, U.S. Department of Energy,
Building Technologies Program, Mailstop EE-2J, 1000 Independence
Avenue, SW., Washington, DC 20585-0121. If possible, please submit all items on a compact disc (CD), in which case it is not necessary to include printed copies. 4. Hand Delivery/Courier: Ms. Brenda Edwards, U.S. Department of
Energy, Building Technologies Program, 950 L'Enfant Plaza, SW., Suite 600, Washington, DC 20024. Telephone: (202) 586-2945. If possible, please submit all items on a CD, in which case it is not necessary to include printed copies.
No telefacsimilies (faxes) will be accepted. For detailed instructions on submitting comments and additional information on the rulemaking process, see section IV of this document (Public
Participation).
Docket: The docket is available for review at www.regulations.gov, including Federal Register notices, comments, and other supporting documents/materials. All documents in the docket are listed in the www.regulations.gov index. However, not all documents listed in the index may be publicly available, such as information that is exempt from public disclosure.
A link to the docket web page can be found at: www.regulations.gov.
The www.regulations.gov web page contains a link to the docket for this notice, along with simple instructions on how to access all documents, including public comments, in the docket. See section IV.A for further information on how to submit comments through www.regulations.gov.
For further information on how to submit a comment or review other public comments and the docket, contact Ms. Brenda Edwards at (202) 586-2945 or by email: Brenda.Edwards@ee.doe.gov.
FOR FURTHER INFORMATION CONTACT: Mr. Mohammed Khan, U.S. Department of
Energy, Office of Energy Efficiency and Renewable Energy, Building
Technologies Program, Mailstop EE-2J, 1000 Independence Avenue, SW.,
Washington, DC 20585-0121. Telephone: (202) 586-7892. E-mail:
Mohammed.Khan@ee.doe.gov.
Mr. Eric Stas, U.S. Department of Energy, Office of the General
Counsel, Mailstop GC-71, 1000 Independence Avenue, SW., Washington, DC 20585-0121. Telephone: (202) 586-9507. E-mail: Eric.Stas@hq.doe.gov.
For information on how to submit or review public comments, contact
Ms. Brenda Edwards, U.S. Department of Energy, Office of Energy
Efficiency and Renewable Energy, Building Technologies Program,
Mailstop EE-2J, 1000 Independence Avenue, SW., Washington, DC 20585- 0121. Telephone: (202) 586-2945. E-mail: Brenda.Edwards@ee.doe.gov.
SUPPLEMENTARY INFORMATION:
Table of Contents
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Introduction
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Authority
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Purpose of the Notice of Data Availability
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Background 1. ASHRAE Standard 90.1-2010 2. ASHRAE Standard 90.1 Proposed Addenda
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Summary of DOE's Preliminary Assessment of Equipment for
Energy-Savings Analysis
-
-
Discussion of Changes in ASHRAE Standard 90.1-2010
-
Commercial Warm-Air Furnaces
-
Commercial Package Air-Conditioning and Heating Equipment 1. Water-Cooled Equipment 2. Evaporatively-Cooled Equipment 3. Variable Refrigerant Flow Equipment 4. Packaged Terminal Air Conditioners and Heat Pumps 5. Small-Duct, High-Velocity, and Through-The-Wall Equipment 6. Single-Package Vertical Air Conditioners and Single-Package
Vertical Heat Pumps
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Air Conditioners and Condensing Units Serving Computer Rooms
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Test Procedures 1. Updates to AHRI 210/240 Test Method 2. Updates to AHRI 340/360 Test Method 3. Updates to UL 727 Test Method 4. Updates to ANSI Z21.47 Test Method 5. Updates to ANSI Z21.10.3 Test Method
-
-
Analysis of Potential Energy Savings
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Annual Energy Use 1. Water-Cooled Air Conditioners 2. Evaporatively-Cooled Air Conditioners 3. Single-Package Vertical Air Conditioners and Heat Pumps
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Shipments
-
Other Analytical Inputs 1. Site-to-Source Conversion 2. Product Lifetime 3. Compliance Date and Analysis Period
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Estimates of Potential Energy Savings
-
-
Public Participation
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Submission of Comments
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Issues on Which DOE Seeks Comment
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Approval of the Office of the Secretary
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Introduction
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Authority
Title III, Part C \1\ of the Energy Policy and Conservation Act of 1975 (EPCA or the Act), Public Law 94-163 (42 U.S.C. 6311-6317, as codified), added by Public Law 95-619, Title IV, Sec. 441(a), established the Energy Conservation Program for Certain Industrial
Equipment, which includes the commercial heating, air-conditioning, and water-heating equipment that is the subject of this rulemaking.\2\ In general, this program addresses the energy efficiency of certain types of commercial and industrial equipment. Relevant provisions of the Act specifically include definitions (42 U.S.C. 6311), test procedures (42
U.S.C. 6314), labelling provisions (42 U.S.C. 6315), energy conservation standards (42 U.S.C. 6313), and the authority to require information
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and reports from manufacturers (42 U.S.C. 6316).
\1\ For editorial reasons, upon codification in the U.S. Code,
Part C was redesignated Part A-1.
\2\ All references to EPCA in this document refer to the statute as amended through the Energy Independence and Security Act of 2007,
Public Law 110-140.
In relevant part here, EPCA contains mandatory energy conservation standards for commercial heating, air-conditioning, and water-heating equipment. (42 U.S.C. 6313(a)) Specifically, the statute sets standards for small, large, and very large commercial package air-conditioning and heating equipment, packaged terminal air conditioners (PTACs) and packaged terminal heat pumps (PTHPs), warm-air furnaces, packaged boilers, storage water heaters, instantaneous water heaters, and unfired hot water storage tanks. Id. In doing so, EPCA established
Federal energy conservation standards that generally correspond to the levels in ASHRAE Standard 90.1, Energy Standard for Buildings Except
Low-Rise Residential Buildings, as in effect on October 24, 1992 (i.e.,
ASHRAE Standard 90.1-1989), for each type of covered equipment listed in 42 U.S.C. 6313(a). EISA 2007 further amended EPCA by adding definitions and setting minimum standards for single-package vertical air conditioners (SPVACs) and single-package vertical heat pumps
(SPVHPs). (42 U.S.C. 6313(a)(10)(A)) The standards for SPVACs and
SPVHPs established by EISA 2007 corresponded to the levels contained in
ASHRAE Standard 90.1-2004, which originated as addendum ``d'' to
Standard 90.1-2001.
In acknowledgement of technological changes that yield energy efficiency benefits, Congress directed DOE through EPCA to consider amending the existing Federal energy efficiency standard for each type of equipment listed, each time ASHRAE Standard 90.1 is amended with respect to such equipment. (42 U.S.C. 6313(a)(6)(A)) For each type of equipment, EPCA directs that if ASHRAE Standard 90.1 is amended,\3\ DOE must adopt amended standards at the new efficiency level in ASHRAE
Standard 90.1, unless clear and convincing evidence supports a determination that adoption of a more stringent level as a national standard would produce significant additional energy savings and be technologically feasible and economically justified. (42 U.S.C. 6313(a)(6)(A)(ii)) If DOE decides to adopt as a national standard the minimum efficiency levels specified in the amended ASHRAE Standard 90.1, DOE must establish such standard not later than 18 months after publication of the amended industry standard. (42 U.S.C. 6313(a)(6)(A)(ii)(I)) However, if DOE determines that a more stringent standard is justified under 42 U.S.C. 6313(a)(6)(A)(ii)(II), then DOE must establish such more stringent standard not later than 30 months after publication of the amended ASHRAE Standard 90.1. (42 U.S.C. 6313(a)(6)(B))
\3\ Although EPCA does not explicitly define the term
``amended'' in the context of ASHRAE Standard 90.1, DOE provided its interpretation of what would constitute an ``amended standard'' in a final rule published in the Federal Register on March 7, 2007
(hereafter referred to as the ``March 2007 final rule''). 72 FR 10038. In that rule, DOE stated that the statutory trigger requiring
DOE to adopt uniform national standards based on ASHRAE action is for ASHRAE to change a standard for any of the equipment listed in
EPCA section 342(a)(6)(A)(i) (42 U.S.C. 6313(a)(6)(A)(i)) by increasing the energy efficiency level for that equipment type. Id. at 10042. In other words, if the revised ASHRAE Standard 90.1 leaves the standard level unchanged or lowers the standard, as compared to the level specified by the national standard adopted pursuant to
EPCA, DOE does not have the authority to conduct a rulemaking to consider a higher standard for that equipment pursuant to 42 U.S.C. 6313(a)(6)(A). DOE subsequently reiterated this position in a final rule published in the Federal Register on July 22, 2009. 74 FR 36312, 36313.
Additionally, EISA 2007 amended EPCA to require that DOE review the most recently published ASHRAE/IES Standard 90.1 with respect to single-package vertical air conditioners and single-package vertical heat pumps in accordance with the procedures established for ASHRAE products under paragraph 42 U.S.C. 6313(a)(6). (42 U.S.C. 6313(a)(10)(B)) However, DOE believes that this requirement is separate and independent from the requirement described in the paragraph above for all ASHRAE products and that it requires DOE to evaluate potential standards higher than the ASHRAE Standard 90.1-2010 level for single- package vertical air conditioners and heat pumps, even if the efficiency levels for SPVACs and SPVHPs have not changed since the last version of ASHRAE Standard 90.1.
As a preliminary step in the process of reviewing the changes to
ASHRAE Standard 90.1, EPCA directs DOE to publish in the Federal
Register for public comment an analysis of the energy savings potential of amended energy efficiency standards, within 180 days after ASHRAE
Standard 90.1 is amended with respect to any of the covered products specified under 42 U.S.C. 6313(a). (42 U.S.C. 6313(a)(6)(A))
On October 29, 2010, ASHRAE officially released for distribution and made public ASHRAE Standard 90.1-2010.\4\ This action by ASHRAE triggered DOE's obligations under 42 U.S.C. 6313(a)(6), as outlined above. This NODA embodies the analysis of the energy savings potential of amended energy efficiency standards, as required under 42 U.S.C. 6313(a)(6)(A)(i). This NODA also addresses DOE's obligations under 42
U.S.C. 6313(a)(10)(B) to consider the most recently published ASHRAE/
IES Standard 90.1 with respect to single-package vertical air conditioners and single-package vertical heat pumps in accordance with the procedures established for ASHRAE products under paragraph 42
U.S.C. 6313(a)(6).
\4\ This industry standard is developed with input from a number of organizations--most prominently ASHRAE, the American National
Standards Institute (ANSI), and the Illuminating Engineering Society of North America (IESNA). Therefore, this document may sometime be referred to more formally as ANSI/ASHRAE/IESNA Standard 90.1-2010.
See http://www.ashrae.org for more information.
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Purpose of the Notice of Data Availability
As explained above, DOE is publishing today's NODA as a preliminary step pursuant to EPCA's requirements for DOE to consider amended energy conservation standards for certain types of commercial equipment covered by ASHRAE Standard 90.1, whenever ASHRAE amends its standard to increase the energy efficiency level for that equipment type. This NODA also addresses the requirements to consider amended energy conservation standards for SPVACs and SPVHPs under 42 U.S.C. 6313(a)(10)(B).
Specifically, this NODA presents for public comment DOE's analysis of the potential energy savings estimates for amended national energy conservation standards for these types of commercial equipment based on: (1) The amended efficiency levels contained within ASHRAE Standard 90.1-2010,\5\ and (2) more stringent efficiency levels. DOE describes these analyses and preliminary conclusions and seeks input from interested parties, including the submission of data and other relevant information.
\5\ For SPVACs and SPVHPs, ASHRAE Standard 90.1-2010 did not change the efficiency levels from the Federal standards, so DOE did not review ASHRAE Standard 90.1 levels for those equipment classes for that purpose, and only estimated potential energy savings for more stringent efficiency levels.
DOE is not required by EPCA to review additional changes in ASHRAE
Standard 90.1-2010 for those equipment types where ASHRAE did not increase the efficiency level. For those types of equipment for which efficiency levels clearly did not change, DOE has conducted no further analysis (with the exception of SPVACs and SPVHPs, for which EPCA requires DOE to review standard levels regardless of whether there was a change to ASHRAE Standard 90.1). However, for certain
Page 25625
equipment classes of ASHRAE covered equipment, DOE found that while
ASHRAE had made changes in ASHRAE Standard 90.1-2010, it was not immediately clear that the revisions to Standard 90.1 would increase the efficiency requirement in that Standard as compared to the existing
Federal energy conservation standards. For example, for commercial warm-air furnaces, ASHRAE Standard 90.1-2010 changes the efficiency metric to thermal efficiency from combustion efficiency, which was the metric used in the previous version of ASHRAE Standard 90.1 (i.e.,
ASHRAE Standard 90.1-2007). However, as discussed in section II.A of this NODA, the change does not result in an increase to the required efficiency, so DOE did not perform additional analysis for that equipment. Therefore, DOE carefully examined the changes for such products in ASHRAE Standard 90.1 in order to thoroughly evaluate the amendments in ASHRAE 90.1-2010, thereby permitting DOE to determine what action, if any, is required under its statutory mandate.
Section II of this notice contains a discussion of DOE's evaluation of each ASHRAE equipment type for which energy conservation standards have been set pursuant to EPCA (``covered equipment''), in order for
DOE to determine whether the amendments in ASHRAE Standard 90.1-2010 have resulted in increased efficiency levels. For covered equipment types determined to have increased efficiency levels in ASHRAE Standard 90.1-2010, DOE subjected that equipment to further analysis as discussed in section III of this NODA.
In summary, the energy savings analysis presented in this NODA is a preliminary step required under 42 U.S.C. 6313(a)(6)(A)(i) and 6313(a)(10)(B). After review of the public comments on this NODA, if
DOE determines that the amended efficiency levels in ASHRAE Standard 90.1-2010 have the potential for additional energy savings for types of equipment currently covered by uniform national standards, DOE will commence a rulemaking to consider amended standards, based upon either the efficiency levels in ASHRAE Standard 90.1-2010 or more-stringent efficiency levels which would be expected to result in significant additional conservation of energy and are technologically feasible and economically justified. In conducting such rulemaking, DOE will address the general rulemaking requirements for all energy conservation standards, such as the anti-backsliding provision \6\ (42 U.S.C. 6316(a); 42 U.S.C. 6295(o)(1)), the criteria for making a determination that a standard is economically justified \7\ (42 U.S.C. 6316(a); 42
U.S.C. 6295(o)(2)(B)(i)-(ii)), and the prohibition on making unavailable existing products with performance characteristics generally available in the U.S.\8\ (42 U.S.C. 6316(a); 42 U.S.C. 6295(o)(4)).
\6\ EPCA contains what is commonly known as an ``anti- backsliding'' provision. (42 U.S.C. 6316(a); 42 U.S.C. 6295(o)(1))
This provision mandates that the Secretary not prescribe any amended standard that either increases the maximum allowable energy use or decreases the minimum required energy efficiency of covered equipment.
\7\ In deciding whether a more stringent standard is economically justified, DOE must review comments on the proposed standard, and then determine whether the benefits of the standard exceed its burdens by considering the following seven factors to the greatest extent practicable:
(1) The economic impact on manufacturers and consumers subject to the standard;
(2) The savings in operating costs throughout the estimated average life of the product in the type (or class), compared to any increase in the price, initial charges, or maintenance expenses of the products likely to result from the standard;
(3) The total projected amount of energy savings likely to result directly from the standard;
(4) Any lessening of product utility or performance likely to result from the standard;
(5) The impact of any lessening of competition, as determined in writing by the Attorney General, likely to result from the standard;
(6) The need for national energy conservation; and
(7) Other factors the Secretary considers relevant.
(42 U.S.C. 6316(a); 42 U.S.C. 6295(o)(2)(B)(i)-(ii)).
\8\ The Secretary may not prescribe an amended standard if interested persons have established by a preponderance of evidence that the amended standard would likely result in unavailability in the U.S. of any covered product type or class of performance characteristics, such as reliability, features, capacities, sizes, and volumes that are substantially similar to those generally available in the U.S. at the time of the Secretary's finding. (42
U.S.C. 6316(a); 42 U.S.C. 6295(o)(4)).
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Background 1. ASHRAE Standard 90.1-2010
As noted above, ASHRAE released a new version of ASHRAE Standard 90.1 on October 29, 2010. The ASHRAE standard addresses efficiency levels for many types of commercial heating, ventilating, air- conditioning (HVAC), and water-heating equipment covered by EPCA.
ASHRAE Standard 90.1-2010 revised the efficiency levels for certain commercial equipment, but for the remaining equipment, ASHRAE left in place the preexisting levels (i.e. the efficiency levels specified in
EPCA or the efficiency levels in ASHRAE Standard 90.1-2007).
Table I.1 below shows the equipment classes (and corresponding efficiency levels) where ASHRAE Standard 90.1-2010 efficiency levels differed from the previous version of ASHRAE Standard 90.1 (i.e.,
ASHRAE Standard 90.1-2007), as well as the requirements for SPVAC and
SPVHP equipment (which were unchanged in ASHRAE Standard 90.1-2010 but which nonetheless must be addressed in this rulemaking for the reasons discussed above). Table I.1 also displays the existing Federal energy conservation standards and the corresponding standard levels in the latest version of ASHRAE Standard 90.1 for those equipment classes.
Section II of this document assesses each of these equipment types to determine whether the amendments in ASHRAE Standard 90.1-2010 constitute increased energy efficiency levels, as would necessitate further analysis of the potential energy savings from amended Federal energy conservation standards, the conclusions of which are presented in the final column of Table I.1.
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Table I.1--Federal Energy Conservation Standards and Energy Efficiency Levels in ASHRAE Standard 90.1-2010 for
Specific Types of Commercial Equipment *
Energy efficiency
Energy efficiency
Federal energy
Energy-savings
ASHRAE equipment class **
levels in ASHRAE levels in ASHRAE
conservation
potential analysis standard 90.1-2007 standard 90.1-2010
standards
required?
Commercial Warm-Air Furnaces
Gas-Fired Commercial Warm-Air
Ec = 80%
Et = 80%
Et = 80%.......... No. See section furnace.
Interrupted or
Interrupted or
II.A. intermittent
intermittent ignition device,
ignition device, jacket losses not jacket losses not exceeding 0.75% of exceeding 0.75% input rating,
of input rating, power vent or flue power vent or damper ***.
flue damper ***.
Commercial Package Air-Conditioning and Heating Equipment--Water-Cooled
Water-cooled Air Conditioner, 11.5 EER........... 12.1 EER (as of 6/ 11.5 EER.......... Yes. See section
>=65,000 and =65,000 and =135,000 and =135,000 and =240,000 Btu/h, Electric
1/11).
II.B.1.
Resistance Heating or No
Heating.
Water-cooled Air Conditioner, 10.8 EER........... 12.2 EER (as of 6/ 10.8 EER.......... Yes. See section
>=240,000 Btu/h, All Other
1/11).
II.B.1.
Heating.
Commercial Package Air-Conditioning and Heating Equipment--Evaporatively-Cooled
Evaporatively-cooled Air
11.5 EER........... 12.1 EER (as of 6/ 11.5 EER.......... Yes. See section
Conditioner, >=65,000 and
1/11).
II.B.2.
=65,000 and
1/11).
II.B.2.
=135,000 and
1/11).
II.B.2.
=135,000 and
1/11).
II.B.2.
=240,000 and
1/11).
II.B.2.
=240,000 and
(as of 6/1/11).
II.B.2.
=65,000 and =135,000 and =240,000 Btu/h,
II.B.3.
Electric Resistance or No
Heating.
VRF Heat Pumps, Air-cooled,
N/A................ 13.0 SEER, 7.7
13.0 SEER, 7.7
No. See section
=65,000 and =65,000 and =135,000 and =135,000 and =240,000 Btu/h, without heat
II.B.3. recovery, Electric Resistance or No Heating.
VRF Heat Pumps, Air-cooled,
N/A................ 9.3 EER, 3.2 COP.. 9.5 EER (electric No. See section
>=240,000 Btu/h, with heat
resistance
II.B.3. recovery, Electric Resistance
heating), 9.3 EER or No Heating.
(no electric resistance heating)[dagger][ dagger][dagger] 3.2 COP.
VRF Heat Pumps, Water-source,
N/A................ 12.0 EER, 4.2 COP. 11.2 EER (=17,000 Btu/h
(>=17,000 Btu/h
and =
>=17,000 Btu/h 17,000 Btu/h and and =65,000 and =65,000 and =135,000 Btu/h, without heat
am]. See section recovery.
II.B.3.
VRF Heat Pumps, Water-source,
N/A................ 9.8 EER, 3.9 COP.. N/A............... Yes[diam][diam][di
>=135,000 Btu/h, with heat
am]. See section recovery.
II.B.3.
Commercial Package Air-Conditioning and Heating Equipment--PTACs and PTHPs[Dagger][Dagger]
Package Terminal Air
EER = 11.0......... EER = 11.7 (as of EER = 11.7........ No. See section
Conditioner, =7,000 and
x Cap[diam]).
x Cap[diam]) (as x Cap[diam]).
II.B.4. 15,000 Btu/h,
II.B.4.
Standard Size (New
Construction)[Dagger][Dagger][
Dagger].
Package Terminal Heat Pump,
EER = 10.8, COP =
EER = 11.9, COP = EER = 11.9, COP = No. See section
=7,000 and 15,000 Btu/h, Standard Size
2.8.
2.9.
2.9.
II.B.4.
(New
Construction)[Dagger][Dagger][
Dagger].
Commercial Package Air-Conditioning and Heating Equipment--SDHV and TTW
Through-the-Wall, Air-cooled
12.0 SEER, 7.4 HSPF 13.0 SEER, 7.4
13.0 SEER, 7.7
No. See section
Heat Pumps, =65,000 and
II.B.6.
=65,000 and
II.B.6.
=65,000 and =65,000 and =65,000 and =240,000 Btu/h.
(downflow), 1.79
am]. See section
SCOP (upflow).
II.C.
Air conditioners, water-cooled, N/A................ 2.60 SCOP
N/A............... Yes[diam][diam][di
=65,000 and =240,000 Btu/h.
(downflow), 2.29
am]. See section
SCOP (upflow).
II.C.
Air conditioners, water-cooled N/A................ 2.55 SCOP
N/A............... Yes[diam][diam][di with fluid economizer, =65,000 and =240,000 Btu/h.
SCOP (upflow).
II.C.
Air conditioners, glycol-
N/A................ 2.50 SCOP
N/A............... Yes[diam][diam][di cooled, =65,000 and =240,000 Btu/h.
(downflow), 1.99
am]. See section
SCOP (upflow).
II.C.
Air conditioners, glycol-cooled N/A................ 2.45 SCOP
N/A............... Yes[diam][diam][di with fluid economizer, =65,000 and =240,000 Btu/h.
SCOP (upflow).
II.C.
* ``Ec'' means combustion efficiency; ``Et'' means thermal efficiency; ``EER'' means energy efficiency ratio;
``SEER'' means seasonal energy efficiency ratio; ``HSPF'' means heating seasonal performance factor; ``COP'' means coefficient of performance; ``Btu/h'' means British thermal units per hour; and ``SCOP'' means sensible coefficient of performance.
** ASHRAE Standard 90.1-2010 equipment classes may differ from the equipment classes defined in DOE's regulations, but no loss of coverage will occur (i.e., all previously covered DOE equipment classes remained covered equipment).
*** A vent damper is an acceptable alternative to a flue damper for those furnaces that draw combustion air from conditioned space.
dagger
ASHRAE Standard 90.1-2010 specifies this efficiency level as 12.2 EER. However, as explained in section
II.B of this NODA, DOE believes this level was a mistake and that the correct level is 11.7 EER.
dagger
dagger Variable Refrigerant Flow (VRF) systems are newly defined equipment classes in ASHRAE Standard 90.1-2010. As discussed in section II.B.3 of this NODA, DOE believes these systems are currently covered by
Federal standards for commercial package air conditioning and heating equipment.
dagger
dagger[dagger] For these equipment classes, ASHRAE sets lower efficiency requirements for equipment with heat recovery systems. DOE believes systems with heat recovery and electric resistance heating would be required to meet the current Federal standard for equipment with electric resistance heating (i.e., the
Federal standard level shown in the table). However, for equipment with heat recovery and no electric resistance heating, DOE believes heat recovery would be an ``other'' heating type allowing for a 0.2 EER reduction in the Federal minimum requirement.
Dagger
The Federal energy conservation standards for this equipment class are specified differently for equipment with cooling capacity =16 inches high, or >=42 inches wide.
diam
``Cap'' means cooling capacity in kBtu/h at 95[deg]F outdoor dry-bulb temperature.
diam
diam ASHRAE Standard 90.1-2010 includes an efficiency level of 10.0 SEER for these products. However, as explained in section II.B.5 of this NODA, DOE believes that ASHRAE did not intend to set an efficiency level for these products.
diam
diam[diam] An energy-savings analysis for this class of equipment was not conducted due to either a lack of data or because there is no equipment on the market that would fall into this equipment class. 2. ASHRAE Standard 90.1 Proposed Addenda
Since officially releasing ASHRAE Standard 90.1-2010 on October 29, 2010, ASHRAE has released three proposed addenda relevant to today's
NODA: Proposed Addendum h, Proposed Addendum i, and Proposed Addendum j. ASHRAE released all three addenda for first public review in March 2011, and the 45-day public review period ends May 9, 2011. Proposed
Addendum h would remove the small-duct high-velocity (SDHV) product class from one of the tables of standards and correct the minimum efficiencies for through-the-wall products. In addition, it would amend the minimum energy efficiency standards (and change the product class names) for water-to-air heat pumps, including some product classes regulated by DOE (e.g., ``water-source'' would become ``water-to-air:
Water loop''), with a proposed effective date immediately upon publication of the addendum.\9\ Proposed Addendum i would amend the minimum energy efficiency standards for SPVACs and SPVHPs. It would also add a new product class designed to address SPVACs and SPVHPs in space-constrained applications. These would become effective January 1, 2012. Proposed Addendum j would remove SDHV from both tables of standards in which it was listed, and would also correct the EER for one product class of evaporatively-cooled units, as discussed in section II.B.5.
\9\ Ground water source (water to air: ground water) and ground source (brine to air: Ground loop) heat pumps are not covered products.
Because these proposed addenda have not yet been approved, DOE is not obligated to address these changes until the addenda are formally adopted and ASHRAE issues the next version of Standard 90.1 (expected in 2013). However, DOE acknowledges that these proposed addenda may affect the market which is addressed in today's NODA. As a result, DOE seeks comments on what impact, if any, these proposed addenda might have, if adopted, on the national energy savings analysis presented in today's NODA. This is Issue 1 under ``Issues on Which DOE Seeks
Comment'' in section IV.B of this NODA.
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Summary of DOE's Preliminary Assessment of Equipment for Energy-
Savings Analysis
DOE has reached a preliminary conclusion for each of the classes of commercial equipment in ASHRAE Standard 90.1-2010 addressed in today's
NODA. For each class of commercial equipment addressed in this NODA, section II presents DOE's initial determination as to whether ASHRAE increased the efficiency level for a given type of product, a change which would require an energy-savings potential analysis. Since DOE is not required by EPCA to review additional changes in ASHRAE Standard 90.1-2010 for those equipment types where ASHRAE did not increase the efficiency level, DOE has conducted no further analysis for those types of equipment where efficiency levels clearly did not change.
Additionally, for equipment where ASHRAE Standard 90.1-2010 has increased the level in comparison to the previous version of ASHRAE
Standard 90.1, but does not exceed the current Federal standard level,
DOE does not have the authority to conduct a rulemaking to consider a higher standard for that equipment pursuant to 42 U.S.C. 6313(a)(6)(A) and did not perform an potential energy savings analysis. For those equipment classes where ASHRAE increased the efficiency level (in comparison to the Federal standard), DOE performed an analysis of the energy-savings potential,
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unless DOE found no products in the market in that equipment class (in which case there is no potential for energy savings) or there was a significant lack of data and information available that would allow DOE to reasonably estimate the potential for energy savings.
Based upon DOE's analysis discussed in section II, DOE has determined that ASHRAE increased the efficiency level for the following equipment classes:
Small, Large, and Very Large Water-cooled Air
Conditioners;
Small, Large, and Very Large Evaporatively-cooled Air
Conditioners;
Certain Small (only those with cooling capacity Air Conditioners and Condensing Units Serving Computer
Rooms.
Out of those equipment classes, when DOE found that equipment is available on the market and adequate information exists to reasonably estimate potential energy savings, DOE performed the analysis of the energy-savings potential which is described in section III. However, when DOE did not find equipment available on the market (such as for small variable refrigerant flow water-source heat pumps with capacities below 17,000 Btu/h), or found that adequate efficiency and/or shipments data was unavailable (such as for air conditioners and condensing units serving computer rooms), DOE did not perform a potential energy savings analysis.
In addition, although ASHRAE did not increase the efficiency level for SPVACs and SPVHPs, DOE is required by EPCA to consider amending the energy conservation standards for these equipment classes using the procedures set forth by 42 U.S.C. 6313(a)(6) for ASHRAE products.
Accordingly, DOE also performed an energy-savings analysis for SPVACs and SPVHPs and presents the results in section III.
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Discussion of Changes in ASHRAE Standard 90.1-2010
Before beginning an analysis of the potential energy savings that would result from adopting the efficiency levels specified by ASHRAE
Standard 90.1-2010 or more-stringent efficiency levels, DOE first determined whether or not the ASHRAE Standard 90.1-2010 efficiency levels actually represented an increase in efficiency above the current
Federal standard levels, thereby triggering DOE action. This section contains a discussion of each equipment class where the ASHRAE Standard 90.1-2010 efficiency level differs from the current Federal standard level, along with DOE's preliminary conclusion regarding the appropriate action to take with respect to that equipment. In addition, this section contains a discussion of DOE's determination with regard to newly created equipment classes in ASHRAE Standard 90.1-2010 (i.e.,
VRF commercial package air-conditioning and heating equipment and air conditioners serving computer rooms), and DOE's decisions with regard to the requirements for analyzing SPVACs and SPVHPs in EPCA. Finally, this section provides a brief discussion of the test procedure updates contained in ASHRAE Standard 90.1-2010.
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Commercial Warm-Air Furnaces
Under 42 U.S.C. 6311(11)(A), a ``warm air furnace'' is defined as
``a self-contained oil- or gas-fired furnace designed to supply heated air through ducts to spaces that require it and includes combination warm air furnace/electric air-conditioning units but does not include unit heaters and duct furnaces.'' In its regulations, DOE defines a
``commercial warm air furnace'' as a ``warm air furnace that is industrial equipment, and that has a capacity (rated maximum input) of 225,000 Btu per hour or more.'' 10 CFR 431.72.
Gas-fired commercial warm-air furnaces are fueled by either natural gas or propane. The Federal minimum energy conservation standard for commercial gas-fired warm-air furnaces corresponds to the efficiency level in ASHRAE Standard 90.1-1989, which specifies for equipment with a capacity of 225,000 Btu/h or more, the thermal efficiency at the maximum rated capacity (rated maximum input) must be no less than 80 percent. 10 CFR 431.77(a). The Federal minimum energy conservation standard for gas-fired commercial warm-air furnaces applies to equipment manufactured on or after January 1, 1994. 10 CFR 431.77.
The current Federal standard for gas-fired commercial warm-air furnaces is in terms of ``thermal efficiency,'' which is defined as
``100 percent minus percent flue loss.'' 10 CFR 431.72. The previous version of ASHRAE Standard 90.1 (i.e., ASHRAE 90.1-2007) specified a minimum efficiency level of 80 percent combustion efficiency, but it defined ``combustion efficiency'' as ``100 percent minus flue losses'' in the footnote to the efficiency table for commercial warm-air gas- fired furnaces, which references ANSI Z21.47-2001, ``Standard for Gas-
Fired Central Furnaces,'' as the test procedure. In its analysis for the 2009 notice of proposed rulemaking (NOPR) regarding standards for
ASHRAE Products in which DOE considered the updates in ASHRAE Standard 90.1-2007, DOE noted that upon reviewing the efficiency levels and methodology specified in ASHRAE Standard 90.1-2007, it concluded that
ASHRAE changed the efficiency metric for gas-fired commercial warm-air furnaces in name only, and not in the actual test or calculation method. 74 FR 12000, 12008-09 (March 20, 2009). Therefore, DOE stated its understanding that despite using the term ``combustion efficiency'' rather than ``thermal efficiency,'' ASHRAE did not intend to change the substance of the metric. Consequently, DOE left the existing Federal energy conservation standards in place for gas-fired commercial warm- air furnaces, which specify a ``thermal efficiency'' of 80 percent using the definition of ``thermal efficiency'' presented at 10 CFR 431.72.
ASHRAE Standard 90.1-2010 updated the tabulated requirements for gas-fired commercial warm-air furnaces to specify a minimum efficiency level of 80 percent ``thermal efficiency'' and references ANSI Z21.47- 2006, ``Standard for Gas-Fired Central Furnaces,'' as the test procedure. ANSI Z21.47-2006 defines ``thermal efficiency'' as ``100 percent minus flue losses,'' which is the same as DOE's definition of
``thermal efficiency'' for this equipment. Because of this, DOE believes that the purpose of the ASHRAE metric change to ``thermal efficiency'' was to clarify the alignment to the existing Federal standards and the ANSI Z21.47-2006 test procedure. As a result, DOE tentatively concluded that this change does not constitute a revision to the actual efficiency level for gas-fired commercial warm-air furnaces and that no further action by the Department is required.
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Commercial Package Air-Conditioning and Heating Equipment
EPCA, as amended, defines ``commercial package air conditioning and heating equipment'' as air-cooled, evaporatively-cooled, water-cooled, or water source (not including ground water source) electrically operated, unitary central air conditioners and central air conditioning heat pumps for commercial use. (42 U.S.C. 6311(8)(A); 10 CFR 431.92)
EPCA also defines ``small,'' ``large,'' and ``very large'' commercial package air conditioning and heating equipment based on the equipment's rated cooling capacity. (42 U.S.C. 6311(8)(B)-(D); 10 CFR 431.92)
``Small commercial package air conditioning and heating equipment'' means equipment rated below 135,000 Btu per hour (cooling capacity).
(42 U.S.C. 6311(8)(B); 10 CFR 431.92) ``Large
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commercial package air conditioning and heating equipment'' means equipment rated--(i) at or above 135,000 Btu per hour; and (ii) below 240,000 Btu per hour (cooling capacity). (42 U.S.C. 6311(8)(C); 10 CFR 431.92) ``Very large commercial package air conditioning and heating equipment'' means equipment rated--(i) at or above 240,000 Btu per hour; and (ii) below 760,000 Btu per hour (cooling capacity). (42
U.S.C. 6311(8)(D); 10 CFR 431.92) 1. Water-Cooled Equipment
The current Federal energy conservation standards for the six classes of water-cooled commercial package air conditioners for which
ASHRAE Standard 90.1-2010 amended efficiency levels are shown in Table
I.1. The Federal energy conservation standards for water-cooled equipment are differentiated based on the cooling capacity (i.e., small, large, or very large) and heating type (i.e., electric resistance heating/no heating or some other type of heating). ASHRAE
Standard 90.1-2010 increased the energy efficiency levels for all six equipment classes to efficiency levels that surpass the current Federal energy conservation standard levels. Therefore, the Department conducted an analysis of the potential energy savings due to amended standards for these products, which is described in section III of this
NODA. 2. Evaporatively-Cooled Equipment
The current Federal energy conservation standards for the six classes of evaporatively-cooled commercial package air conditioners for which ASHRAE Standard 90.1-2010 amended efficiency levels are shown in
Table I.1. Similar to water-cooled equipment, Federal energy conservation standards divide evaporatively-cooled equipment based on the cooling capacity (i.e., small, large, or very large) and heating type (i.e., electric resistance heating/no heating or some other type of heating). ASHRAE Standard 90.1-2010 increased the energy efficiency levels for all six equipment classes to efficiency levels that surpass the current Federal energy conservation standard levels.
DOE reviewed the market for evaporatively-cooled equipment and could not identify any models available on the market in the ``small'' unit product class (i.e., cooling capacity = 135,000 and = 240,000 Btu/h) evaporatively-cooled air conditioners, DOE was able to identify a number of models on the market, and, therefore, DOE conducted an analysis of the potential energy savings for these products which is discussed in section III. For very large evaporatively-cooled air conditioners, ASHRAE Standard 90.1-2010 set the efficiency level for equipment with electric resistance or no heating at 11.9 EER and for equipment with all other heating at 12.2 EER. However, ASHRAE historically has set the levels for equipment with other heating at 0.2
EER points below the efficiency levels for equipment with electric heating or no heating, which would make the expected efficiency level for very large evaporatively-cooled equipment with other heating 11.7
EER. In February 2011, the Department received a letter from the Air-
Conditioning, Heating, and Refrigeration Institute (AHRI) indicating that the ASHRAE Standard 90.1-2010 efficiency level for very large evaporatively-cooled equipment with other heating is incorrect, and that the correct minimum energy efficiency standard for this category is 11.7 EER, as would be expected given the historical ASHRAE Standard 90.1 efficiency levels for these products. (AHRI, No. 0001 at p. 1)
Further, AHRI indicated that at its winter 2011 meeting, the ASHRAE 90.1 committee approved an addendum for public review that corrects this error. In March 2011, ASHRAE released proposed Addendum j to
ASHRAE Standard 90.1-2010, which corrects the value from 12.2 to 11.7
EER. Based on release of the public review draft of this addendum, the
Department has tentatively decided to analyze the potential energy savings for this category at an ASHRAE Standard 90.1 level of 11.7 EER. 3. Variable Refrigerant Flow Equipment
ASHRAE 90.1-2010 created a separate product class for variable refrigerant flow (VRF) air-conditioning and heating equipment. These products are currently covered under DOE's standards for commercial air conditioners and heat pumps, but they are not broken out as a separate product class.
In general, a VRF system will have a single condensing unit serving multiple evaporator coils within a building. Specific ``subclasses'' of variable refrigerant flow heat pumps equipped with heat recovery capability have been specified in ASHRAE/IES Standard 90.1-2010 with lower efficiency requirements than specified for VRF systems without heat recovery. (Heat recovery capability provides for shuttling of heat from one part of the building to another and allows for simultaneous cooling and heating of different zones within a building.)
Specifically, the efficiency requirements in ASHRAE Standard 90.1-2010 for air-cooled VRF heat pumps with heat recovery are equivalent to the
Federal minimum energy conservation standards defined for air-cooled heat pumps with ``all other heating system types that are integrated into the equipment,'' and the efficiency requirements for air-cooled
VRF heat pumps without heat recovery are equivalent to the Federal minimum standards for air-cooled heat pumps with electric or no heating.\10\ The VRF systems with heat recovery specified by ASHRAE may often have electric resistance heating systems, as a back-up. For air- cooled VRF heat pump systems that have both electric resistance heating and heat recovery heating capability, the Department has tentatively concluded that these systems must meet the efficiency requirements contained in EPCA for small, large, and very large air-cooled central air-conditioning heat pumps with electric resistance heating, which are codified at 10 CFR 431.97(b). (42 U.S.C. 6313(a)(7)-(9)) In addition, the Department has tentatively concluded that air-cooled VRF systems without electric resistance heating but with heat recovery can qualify as having an ``other'' means of heating and that these systems must meet the efficiency requirements contained in EPCA for small, large, and very large air-cooled central air-conditioning heat pumps with other heating, which are codified at 10 CFR 431.97(b). (42 U.S.C. 6313(a)(7)-(9))
\10\ Section 136 of the Energy Policy Act of 2005 (EPACT 2005;
Pub, L. 109-58) amended EPCA to include separate minimum efficiency requirements for commercial package air-cooled air conditioners and heating equipment with ``all other heating system types that are integrated into the equipment'' and with electric resistance or no heating.
Table II.1 shows the ASHRAE Standard 90.1-2010 efficiency levels for
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VRF water-source heat pumps in comparison to the current Federal minimum energy conservation standards for water-source heat pumps, which DOE has preliminarily determined would apply to VRF systems. For water-source VRF heat pumps, ASHRAE Standard 90.1-2010 generally maintains the existing energy efficiency requirements that apply to commercial package air-conditioning and heating equipment for the VRF systems, with several notable exceptions. For VRF water-source heat pumps under 17,000 Btu/h and VRF water-source heat pumps over 135,000
Btu/h, ASHRAE Standard 90.1-2010 raises the efficiency levels above current Federal energy conservation standards (or in the case of water- source heat pumps over 135,000 Btu/h, ASHRAE sets standards for products where DOE did not previously have standards). As a result, the
Department conducted further analysis for these classes. DOE began by reviewing the current market for VRF water-source heat pumps with cooling capacities below 17,000 Btu/h or above 135,000 Btu/h and less than 760,000 Btu/h. The Department did not identify any models under 17,000 Btu/h on the market. DOE did identify 19 models above 135,000
Btu/h on the market and attempted to contact the manufacturer producing most of these models, but DOE was unable to obtain EER information for most of the models and has no shipment information for this product class. Because DOE could not identify any VRF water-source heat pumps being manufactured with cooling capacities below 17,000 Btu/h, DOE believes that there are no energy savings associated with this equipment class. Therefore, DOE did not perform a potential energy- savings analysis for this equipment. In addition, due to the lack of available information and data on VRF water-source heat pumps with cooling capacities above 135,000 Btu/h at this time, the Department has not conducted a preliminary energy saving estimate for the additional energy savings beyond the levels anticipated in ASHRAE Standard 90.1- 2010 for this VRF water source heat pump product class. DOE is requesting public comment regarding the market for this equipment and is seeking data and information that would allow it to accurately characterize the energy savings from amended energy conservation standards for these products. This is identified as Issue 3 in section
IV.B ``Issues on Which DOE Seeks Comment.''
In addition to the changes for the two equipment classes discussed above, ASHRAE Standard 90.1-2010 includes efficiency levels for VRF water-source heat pumps that provide for a 0.2 EER reduction in the efficiency requirement for systems with heat recovery. However, the current Federal minimum standards for water-source heat pumps do not provide for any reduction in the EER requirements for equipment with
``other'' heating types. Therefore, the 0.2 EER reduction below the current Federal standard levels for the VRF water-source heat pump equipment classes in which ASHRAE did not raise the standard from the existing Federal minimum for water-source heat pumps (i.e., water- source heat pumps with cooling capacities >= 17,000 and = 65,000 and = 17,000 12.0 EER.......... 12.0 EER (without and.
heat recovery).
= 65,000 12.0 EER.......... 12.0 EER (without and.
heat recovery).
=
N/A............... 10.0 EER (without 135,000 and.
heat recovery). 2O to +0.05 in H2O). Since DOE does not regulate or require manufacturers to certify part-load ratings, the change from
IPLV to IEER does not affect the Federal energy conservation standards.
Also, DOE believes that the added tolerance criterion does not significantly impact the measure of energy efficiency. DOE seeks comments on its preliminary determination that the changes to AHRI 340/ 360-2007 do not significantly impact energy efficiency ratings. This is identified as Issue 9 in section IV.B, ``Issues on Which DOE Seeks
Comment.'' 3. Updates to UL 727 Test Method
In 2006, Underwriters Laboratories (UL) updated its standard UL 727, Standard for Safety for Oil-Fired Central Furnaces. DOE's test procedure for measuring the energy efficiency of commercial warm-air furnaces at 10 CFR 431.76 only references the procedures pertinent to the measurement of the steady-state efficiency for this equipment in UL 727 (i.e., the measurements described in sections 1 through 3, 37 through 42 (but not 40.4 and 40.6.2 through 40.6.7), 43.2, 44, 45, and 46 of UL 727). Therefore, when reviewing the test procedure, DOE only looked at the changes to these sections. Most of the changes to UL 727 were to reorganize the document and convert it to the Standard
Generalized Markup Language (SGML) \14\ as a way of keeping the data consistent, reusable, shareable, and portable. In addition, UL removed a section from the scope that allowed a manufacturer to propose appropriate revisions to requirements of UL 727 if the product's new features, components, materials, or systems are unsafe to be tested with the UL 727 Standard, provided that the new revisions conforms to the intent of the Standard. DOE believes that these changes to UL 727- 2006 do not significantly impact the energy efficiency ratings and seeks comments as to its tentative conclusion. This is identified as
Issue 9 in section IV.B, ``Issues on Which DOE Seeks Comment.''
\14\ SGML is a document markup language developed by the
International Organization for Standardization (ISO) to allow for the sharing of machine-readable documents in government or law.
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Updates to ANSI Z21.47 Test Method
In 2006, the American National Standards Institute (ANSI) updated
ANSI Z21.47, Standard for Gas-Fired Central Furnaces. DOE's test procedure for measuring the energy efficiency of gas-fired warm air furnaces at 10 CFR 431.76 only references the procedures contained in
ANSI Z21.47 that are relevant to the steady-state efficiency measurement (i.e., sections 1.1, 2.1 through 2.6, 2.38, and 4.2.1 of
ANSI Z21.47). As a result, DOE focused its test procedure review on the relevant sections of ANSI Z21.47 that DOE's test procedure references.
In those sections referenced by DOE's test procedures, ANSI made several updates. First, ANSI updated the scope section to include optional special construction provisions for furnaces designed to operate at altitudes over 2000 feet. ANSI also added an entirely new section for a Proved Igniter and renumbered the other sections to accommodate this addition. The newly added section does not fall under the procedures relevant for steady-state efficiency measurement; however, it does cause the Thermal Efficiency section (which is relevant for the steady-state efficiency measurement) to move from section 2.38 to section 2.39 of the test procedure. DOE preliminarily determined that these changes to ANSI Z21.47-2006 do not impact the energy efficiency ratings for gas-fired furnaces and seeks comments regarding this tentative conclusion. This is identified as Issue 9 in section IV.B, ``Issues on Which DOE Seeks Comment.'' 5. Updates to ANSI Z21.10.3 Test Method
In 2004, ANSI updated ANSI Z21.10.3, Gas Water Heaters, Volume III,
Storage Water Heaters with Input Ratings Above 75,000 Btu Per Hour,
Circulating and Instantaneous. DOE's test procedure for gas-fired water heaters at 10 CFR 431.106 only references sections 2.9 (Thermal
Efficiency) and 2.10 (Standby Loss) of the ANSI Z.21.10 test procedure.
Accordingly, DOE's review focused on those sections, as well as any other sections to which sections 2.9 and 2.10 refer. In the updated version, ANSI moved both of these sections to Exhibit G. In addition,
ANSI added a provision to limit the duration of the standby loss test to a maximum of 48 hours if there is no cutout (i.e., the thermostat acts to shut off the burner) after the 24-hour mark. Currently, there is already an additional stipulation in DOE's test procedure at 10 CFR 431.106 that the standby test should last from the first fuel and/or electric consumption measurement until either the first cutout after the 24-hour mark or a maximum of 48 hours, if the water heater is not in the heating mode at that time. This stipulation was added by a direct final rule amending the test procedure for commercial water heaters (which was published on October 21, 2004) to limit the duration of the standby test and reduce the testing burden for manufacturers. 69
FR 61974, 61979.
DOE notes that its provision limiting the duration of the standby loss test is slightly different than the provision included in ANSI Z 21.10.3-2004. Using DOE's test procedure, if the water heater is in heating mode at the 48-hour mark, the tester is instructed to let the heating mode complete before ending the test. However, the updated ANSI
Z21.10.3 test method directs the tester to end the test at 48 hours regardless of whether the water heater is in heating mode. DOE believes that this slight difference between the ANSI test procedure and the current DOE test procedure may have a very small impact on the measured energy efficiency if the water heater has not yet cut off after 24 hours and is in heating mode at the 48-hour mark. In such a situation, the DOE test procedure would allow the water heater to continue operating in heating mode to continue until a cutout before ending the test, whereas the ANSI test method would end the test immediately and possibly not capture the energy used during that final heating cycle.
However, as noted above, DOE's test procedure already includes a provision to address the standby mode energy loss that is independent of the ANSI Z21.10.3 test method. Therefore, the update to the provision for the duration of the standby mode test in ANSI Z21.10.3 would be superseded by DOE's test requirements at 10 CFR 431.106 and would not change the standby test method. As a result, DOE believes that the new changes to ANSI Z21.10.3 would not significantly affect the measure of energy efficiency. DOE seeks comment regarding its preliminary conclusion that the updated ANSI Z21.10.3-2004 does not significantly impact energy efficiency ratings of
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commercial gas-fired water heaters. This is identified as Issue 9 in section IV.B, ``Issues on Which DOE Seeks Comment.''
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Analysis of Potential Energy Savings
As required under 42 U.S.C. 6313(a)(6)(A), DOE performed an analysis to determine the energy-savings potential of amending Federal minimum energy conservation standard levels to the efficiency levels specified in ASHRAE Standard 90.1-2010, as well as more-stringent efficiency levels than those specified in ASHRAE Standard 90.1-2010. As explained above, DOE's energy-savings analysis is limited to types of equipment covered by Federal energy conservation standards for which the amended ASHRAE Standard 90.1-2010 increased the efficiency levels and for which a market exists and sufficient data are available.\15\
Based upon the conclusions reached in section II, DOE is conducting the energy-savings analysis for eight equipment classes of water-cooled and evaporatively-cooled products: (1) Small water-cooled air conditioners with electric resistance or no heating (65,000 to less than 135,000
Btu/h); (2) small water-cooled air conditioners with other heating
(65,000 to less than 135,000 Btu/h); (3) large water-cooled air conditioners with electric resistance or no heating (135,000 to less than 240,000 Btu/h); (4) large water-cooled air conditioners with other heating (135,000 to less than 240,000); (5) very large water-cooled air conditioners with electric resistance or no heating (240,000 Btu/h to less than 760,000 Btu/h); (6) very large water-cooled air conditioners with other heating (240,000 Btu/h to less than 760,000 Btu/h); (7) very large evaporatively-cooled air conditioners with electric resistance or no heating (240,000 Btu/h to less than 760,000 Btu/h); and (8) very large evaporatively-cooled air conditioners with other heating (240,000
Btu/h to less than 760,000 Btu/h).
\15\ As discussed in section II, when no products are available on the market or no reliable data exist for calculating potential energy savings, DOE did not perform an analysis. The products for which ASHRAE Standard 90.1-2010 increased the efficiency level, but for which DOE did not perform an analysis due to lack of a market or lack of data include: (1) VRF water-source heat pumps under 17,000
Btu/h (see section II.B.3); (2) VRF water-source heat pumps over 135,000 Btu/h (see section II.B.3); and (3) air conditioners and condensing units serving computer rooms (see section II.C).
In addition, although ASHRAE did not increase the efficiency level for SPVACs and SPVHPs, DOE is required by EPCA to consider amending the energy conservation standards for these equipment classes using the procedures set forth by 42 U.S.C. 6313(a)(6) for ASHRAE products.
Accordingly, DOE also performed an energy-savings analysis for four equipment classes of SPVACs and SPVHPs where there is a market and sufficient data are available: (1) Single-phase SPVACs under 65,000
Btu/h; (2) three-phase SPVACs under 65,000 Btu/h; (3) single-phase
SPVHPs under 65,000 Btu/h; and (4) three-phase SPVHPs under 65,000 Btu/ h.
The following discussion provides an overview of the energy-savings analysis conducted for these twelve classes of products, followed by summary results of that analysis. For each efficiency level analyzed,
DOE calculated the potential energy savings to the Nation as the difference between a base-case forecast (without amended standards) and the standards-case forecast (with amended standards). The national energy savings (NES) refers to cumulative energy savings for a 30-year period that differs by product. The analysis is based on a stock accounting method. In the standards case, equipment that is more efficient gradually replaces less-efficient equipment over time. This affects the calculation of the potential energy savings, which are a function of the total number of units in use and their efficiencies.
Savings depend on annual shipments and equipment lifetime. Inputs to the energy-savings analysis are presented below, and details are available in the ASHRAE NODA TSD on DOE's website.\16\
\16\ The ASHRAE NODA TSD is available on the webpage for ASHRAE
Products at: http://www1.eere.energy.gov/buildings/appliance_standards/commercial/ashrae_products_docs_meeting.html.
While DOE did not have sufficient data to follow this analytical method for large SPVACs, DOE approximated the energy savings potential for this product class based on the energy savings results from the small SPVAC product classes. The calculation method and results for estimating the energy savings potential for large SPVACs are summarized in section III.D.
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Annual Energy Use
DOE's analysis of the annual unit energy consumption (UEC) for each class of equipment analyzed was based on the use of building simulation models or previously available building simulation data for equipment at or near the current Federal standard baseline for each equipment class analyzed. DOE then used a scaling process to assess the UEC corresponding to higher efficiency levels, including the efficiency levels provided in ASHRAE 90.1-2010. These UEC estimates form the basis of the national energy savings estimates discussed in section III.D.
This section describes the energy use analysis performed for water- cooled and evaporatively-cooled products, as well as for SPVUs. For each of these equipment types, the Federal standard and higher efficiency levels are expressed in terms of an efficiency metric or metrics (EER for cooling efficiency, Coefficient of Performance (COP) for heating efficiency). For each equipment class, this section describes how DOE developed estimates of annual energy consumption at the baseline efficiency level and higher levels for each equipment type. More detailed discussion is found in the ASHRAE NODA TSD. 1. Water-Cooled Air Conditioners
The analysis to assess the per-unit energy saving of water-cooled air conditioners began with review of the existing market, as well as the review of historical shipments data provided by AHRI for the period from 1989-2009.\17\ The review of the market for equipment from 65,000
Btu/h to 760,000 Btu/h suggested that most of the water-cooled air conditioner units currently on the market are designed for installation inside of commercial buildings (as opposed to on building rooftops), and the shipments data suggested that in recent years, shipments were dominated by larger equipment (>= 240,000 Btu/h capacity), with relatively few shipments of smaller-capacity units. Given these findings, DOE's analysis of energy savings focused on typical applications for this larger equipment. Review of manufacturer's literature suggested that a common application is floor-by-floor cooling in a multi-story building.
\17\ Air-Conditioning, Heating, and Refrigeration Institute,
Historical Shipment Data Commercial Air Conditioners Water Cooled, 2011. This information was provided by AHRI to the U.S. Department of Energy on March 4, 2011.
To provide an estimate of the energy use of water-cooled air conditioners in this application, DOE used annual hourly simulation data developed from computer simulations of a prototypical commercial office building. The prototype building model was a 3-story, 53,600 square foot (sf) commercial office building developed as part of DOE's commercial reference building models.\18\ This building has each floor
Page 25638
served by a separate packaged air-conditioning unit. The hourly data used in this analysis were previously developed from simulations using the DOE EnergyPlus \19\ building simulation software and reflected building simulations in 15 climate locations in the U.S., with each climate representing one of 15 climate regions that have been developed in DOE's Building Energy Codes Program and subsequently used in the development of the commercial reference building models.
\18\ The commercial reference building models are available on
DOE's website as Energy Plus input files at: http://www1.eere.energy.gov/buildings/commercial_initiative/new_construction.html. Documentation of the model development is provided in: Deru, M., et al. U.S. Department of Energy Commercial
Reference Building Models of the National Building Stock. (NREL/TP- 5500-46861) (2011).
\19\ For more information on EnergyPlus, refer to DOE's
EnergyPlus documentation, available at: http://apps1.eere.energy.gov/buildings/energyplus/energyplus_documentation.cfm. EnergyPlus software is freely available for public download at: http://apps1.eere.energy.gov/buildings/energyplus/energyplus_about.cfm.
The office building model selected utilized packaged variable air volume rooftop cooling units in the original reference building simulations, with each packaged unit serving one floor of the office model. DOE determined that the cooling thermal loads from modeling of this type of equipment would be representative of similar cooling distribution systems served by larger water-cooled equipment that also provides floor-by-floor cooling and serves multiple building thermal zones. EnergyPlus does not have an equipment simulation model developed around a water-cooled air conditioner for this application. For this reason, DOE relied on using the previously developed hourly cooling thermal load, air flow, and system air temperature data for the air- cooled packaged rooftop equipment used in the medium office reference building model. Since the thermal loads for the specific application would be essentially the same whether served by air-cooled or water- cooled packaged cooling equipment, and since the water-cooled packaged air conditioner equipment performance would be modeled explicitly in the spreadsheet, DOE believes this is approach provides an accurate method of estimating energy consumption for the water-cooled equipment classes.
To process the hourly data into annual equipment energy consumption for water-cooled air conditioners, DOE developed a spreadsheet model of the typical equipment performance using actual manufacturer performance data for a 25-ton water-cooled air conditioner. Cooling capacity and condenser power consumption curve fits to this data were developed using polynomial relationships and the independent variables recommended for modeling of cooling efficiency for water-source heat pumps in Energy Plus. In addition, DOE used part-load performance degradation curves previously developed for air-source air conditioners that already existed in the medium office reference building model. As these part-load curves reflect the effects of compressor cycling at part load, it was determined that these curves should be representative of the compressor cycling impacts for water-cooled air conditioners as well.
For each climate, DOE's spreadsheet model sized the equipment to reflect the sizing in the original simulation's hourly load data. To accurately account for fan power, DOE used the normalized fan power- versus-supply air flow curves in the original office reference building model.
The performance equations developed in this spreadsheet model separately accounted for the water-cooled gross cooling capacity and power consumption as a function of entering air conditions and supply water temperature and flow rate. In addition, the spreadsheet model requires an hourly entering water temperature and entering water flow rate. For this analysis, a simple cooling tower supply water temperature model was developed based on a defined control profile with minimum 70 [deg]F return water temperature and using a 7 [deg]F approach temperature (the temperature between the return water temperature from the cooling tower and the outdoor air wet bulb temperature). Condenser water flow rates were assumed to be equivalent to the nominal rating condition water flow rates for all cooling hours.
For analysis of energy use at each specific efficiency (EER) level,
DOE first developed estimates for the condenser efficiency (condenser- only cooling COP) based on the nominal rating conditions. This was done by backing out the estimated fan power at nominal rating conditions from the input power and separately accounting for the impact of fan heat to arrive at the gross cooling capacity of the equipment. DOE developed estimates of peak fan power at design air flow conditions and used the fan power versus flow relationships to adjust the fan power appropriately for periods when air flow was not at design air flow rates.
Using the spreadsheet model, for each of the 15 climates, DOE first developed the annual equipment condenser energy consumption and blower energy consumption for nominal 11 EER water-cooled equipment, with 11
EER being the current Federal standard for water-cooled air conditioners with electric resistance or no heating, 240,000 Btu/h to less than 760,000 Btu/h . These were then normalized by dividing by the equipment capacity in cooling tons. The sum of the resulting condenser energy per cooling ton and blower energy per cooling ton represents the annual energy consumption per cooling ton for equipment at the 11 EER efficiency level. The resulting per-ton energy consumption figures were then multiplied by the typical equipment capacities developed for each water-cooled equipment class analyzed to establish the Unit Energy
Consumption (UEC) values for each equipment class at that 11 EER level.
To assess the annual energy consumption at the specific efficiency levels analyzed, DOE developed estimates of the condenser-only cooling
COP for each efficiency level. It then multiplied the annual condenser energy consumption for the 11 EER equipment for each climate by the ratio of the baseline condenser-only cooling COP to the condenser-only cooling COP at the higher efficiency levels.
The annual fan energy consumption estimates were held constant at the baseline level for all higher standards. A detailed engineering analysis of higher efficiency options might suggest a number of different ways to improve the EER including reducing supply fan energy consumption. However, several downsides to this approach were identified. First, the supply fan accounts for a relatively small portion of the energy use as compared to the condenser at the rating condition. In addition, because it appears that much of this equipment is installed inside the building space, changes which reduce fan power, such as increased case size and lower face velocity over the evaporator coil, would decrease the amount of rentable space available within the building. Accordingly, for the assessment of energy savings in this
NODA, supply fan energy use was held constant. The UEC for each efficiency level analyzed is the sum of the annual condenser energy consumption and the fan power. From these climate-region-specific results, DOE developed national average UEC values at each efficiency level using weighting factors developed for medium and large commercial office building floor space as part of the development of the DOE reference building models. A comparison of these office weighting factors with cumulative weighting factors developed for the larger stock of commercial floor space is provided in the ASHRAE NODA TSD.
Table III.1 shows the UEC estimates for the current Federal baseline levels, the proposed ASHRAE levels, and for the higher efficiency levels for the six water-cooled air conditioner classes analyzed.
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Table III.1--National UEC Estimates for Water-Cooled Air Conditioners
Small water-
Large water-
Very large water- cooled air
Small water-
cooled air
Large water-
cooled air
Very large water- conditioners
cooled air
conditioners
cooled air
conditioners
cooled air electric or no
conditioners
electric or no
conditioners
electric or no
conditioners heat 65,000- other heat 65,000- heat 135,000-
other heat
heat 240,000-
other heat 135,000 Btu/h
135,000 Btu/h
240,000 Btu/h 135,000-240,000
760,000 Btu/h 240,000-760,000
Btu/h
Btu/h
Average Cooling Capacity (tons).......
8
8
15
15
35
35
Efficiency Level (EER)
Base Case--Federal Standard...........
11.5
11.3
11.0
11.0
11.0
10.8
Efficiency Level 1....................
12.1
11.9
12.5
12.3
12.4
12.2
Efficiency Level 2....................
13.0
13.0
13.0
13.0
13.0
13.0
Efficiency Level 3....................
14.0
14.0
14.0
14.0
14.0
14.0
Efficiency Level 4....................
15.0
15.0
15.0
15.0
* NA
* NA
Efficiency Level 5--``Max-Tech''--....
16.4
16.4
16.1
16.1
14.8
14.8
Unit Energy Consumption (kWh/yr)
Base Case--Federal Standard...........
9,199
9,322
17,838
17,838
41,621
42,205
Efficiency Level 1....................
8,855
8,966
16,206
16,402
38,041
38,504
Efficiency Level 2....................
8,396
8,396
15,743
15,743
36,733
36,733
Efficiency Level 3....................
7,953
7,953
14,911
14,911
34,793
34,793
Efficiency Level 4....................
7,566
7,566
14,186
14,186
*NA
*NA
Efficiency Level 5--``Max-Tech''--....
7,101
7,101
13,490
13,490
33,422
33,422
*An efficiency level 4 was not identified for very large water-cooled air conditioners. 2. Evaporatively-Cooled Air Conditioners
The analysis to assess the per-unit energy use of evaporatively- cooled air conditioners began with review of the existing market. DOE did not identify any current models of evaporatively-cooled air conditioners with less than 240,000 Btu/h cooling capacity. The review of the market suggested that all of the currently shipping units appeared to be packaged rooftop evaporatively-cooled air conditioner units. Based on the available models, DOE estimated the average capacity at 40 tons. Because of this, DOE's analysis of energy savings focused on typical applications for the very large equipment class.
Because of the large capacity, DOE believes that a common system design would also be a packaged variable air volume (VAV) system. DOE modified the 3-story office reference building model discussed previously to serve as the simulation model for the very large evaporatively-cooled air conditioner equipment class.
The Energy Plus simulation tool has the capability to model evaporatively-cooled unitary air conditioners with only minor modifications from the air-cooled unitary air conditioner equipment models that were used in the original DOE medium office reference building model. DOE was not able to derive separate performance curves for evaporatively-cooled equipment, as these data were not available in the manufacturer literature reviewed. Therefore, DOE modified the air- cooled model using simulation defaults provided in the Energy Plus documentation for modeling evaporatively-cooled air conditioners. These modifications are discussed in the ASHRAE NODA TSD.
DOE performed simulations of the medium office reference building model in the 15 climates identified previously at an 11 EER efficiency level, because 11 EER is the current Federal standard for evaporatively-cooled air conditioners with electric resistance or no heating. To do this, DOE first developed estimates for the condenser- only cooling COP based on the nominal rating conditions as input for the simulation models. DOE used the fan power performance curves and peak fan power assumptions in the reference building model directly.
Using the spreadsheet model, for each of the 15 climates, DOE developed the annual equipment condenser energy consumption and blower energy consumption for the 11 EER evaporatively-cooled equipment simulated. These values were then normalized by dividing by the equipment capacity in cooling tons. The sum of the resulting condenser energy per cooling ton and blower energy per cooling ton represents the annual energy consumption per cooling ton for equipment at that 11 EER efficiency level. These per-ton energy consumption figures were then multiplied by the selected equipment capacities for the evaporatively- cooled equipment class analyzed to establish the UEC values for each equipment class at an 11 EER level.
To assess the annual energy consumption at the specific efficiency levels analyzed, DOE developed estimates of the condenser-only cooling
COP for each efficiency level. It then multiplied the baseline annual condenser energy consumption developed for each climate by the ratio of the baseline condenser-only cooling COP at 11 EER to the condenser-only cooling COP at the efficiency levels analyzed.
The annual fan energy consumption estimates were held constant at the baseline level for all higher standards. As with water-cooled air conditioners, a detailed engineering analysis might suggest that reduction in supply fan power might be a path to improved EER; however,
DOE did not conduct such a detailed analysis. Because supply fan power is a relatively small fraction of total system power at rating conditions, DOE concluded that improvement in condenser efficiency is likely a necessary path to achieve the most
Page 25640
significant system efficiency improvements. The UEC for each efficiency level analyzed is the sum of the annual condenser energy consumption and the fan power. As with water-cooled air conditioners discussed previously, DOE developed national average UEC values at each efficiency level using weighting factors developed for medium and large commercial office building floor space as part of the development of the DOE reference building models.
Table III.2 shows the unit energy consumption estimates for the current Federal baseline levels, the proposed ASHRAE levels, and for the higher efficiency levels for the very large evaporatively-cooled air conditioner classes.
Table III.2--National UEC Estimates for Evaporatively-Cooled Air Conditioners
Large evaporatively-
Large evaporatively- cooled air conditioner cooled air conditioner electric or no heat
other heat 240,000- 240,000-760,000 Btu/h
760,000 Btu/h
Average Cooling Capacity (tons)
40
40
Efficiency Level (EER)
Base case.....................................................
11.0
10.8
Level 1--ASHRAE...............................................
11.9
11.7
Level 2.......................................................
12.5
12.5
Max Tech......................................................
13.1
13.1
Unit Energy Consumption (kWh/yr)
Base case.....................................................
47,171
47,766
Level 1--ASHRAE...............................................
44,732
45,243
Level 2.......................................................
43,294
43,294
Max Tech......................................................
41,983
41,983
-
Single-Package Vertical Air Conditioners and Heat Pumps
Based on data developed during previous analysis of SPVU equipment by DOE,\20\ the Department believes that approximately 60 percent of the SPVU shipments go to educational facilities, the majority of which are for space conditioning of modular classroom buildings. Another approximately 20 percent of the shipments go to providing cooling for non-comfort cooling applications such as telecommunications and electronics enclosures. The remainder is used in a wide variety of commercial buildings including offices, temporary buildings, and some lodging facilities. In many of these commercial building applications, the buildings served are expected to be of modular construction.
\20\ U.S. Department of Energy, Technical Support Document:
Energy Efficiency Program for Commercial and Industrial Equipment:
Efficiency Standards for Commercial Heating, Air-Conditioning, and
Water Heating Equipment Including Packaged Terminal Air-Conditioners and Packaged Terminal Heat Pumps, Small Commercial Packaged Boiler,
Three-Phase Air-Conditioners and Heat Pumps
-
