### 46464 

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices

L. 92-463, 86 Stat. 770) requires that agencies publishthese notices inthe Federal Register to allow for public participation. This notice announces the meeting ofthe Biomass Research and Development Technical Advisory Committee

DATES: August 1, 2002.

TIME: 8:30 a.m.

ADDRESSES: Hilton Crystal City Hotel at National Airport, Crystal Room, 2399 Jefferson Davis Highway, Arlington, VA 22202.

FOR FURTHER INFORMATION CONTACT: Douglas E. Kaempf, Designated Federal Officer for the Committee, Office of Energy Efficiency and Renewable Energy, U.S. Department ofEnergy, 1000 Independence Avenue, SW, Washington, DC 20585; (202) 586-7766.

SUPPLEMENTARY INFORMATION: 

### Purpose of Meeting: To provide advice and guidance that promotes research and development leading to the production ofbiobased industrial products.



### TentativeAgenda:Agenda will include discussions on the following:

• Full committee discussion onthe development ofa Vision document for federal biomass research and development programs.



### Public Participation: In keeping with procedures, members ofthe public are welcome to observe thebusiness ofthe Biomass Research and Development Technical Advisory Committee. To attend the meeting and/or to make oral
statements regarding any ofthe items on the agenda, you should contactDouglas E. Kaempfat 202-586-7766 or 

### Bioenergy@ee.doe.gov (email). You
must make yourrequest for an oral
statement at least 5 business days before the meeting. Members ofthe public will be heard inthe order inwhich they sign
up atthe beginning ofthe meeting. Reasonable provision willbe made to includethe scheduled oral statements

on the agenda. The Chair ofthe Committee will make everv effort to hear the views ofall interested parties. Ifyou would like to file a written
statement with the Committee, you may do so eitherbefore or after the meeting. The Chair will conductthe meeting to facilitate the orderly conduct of business.



### Minutes: The minutes ofthe meeting willbe available for public review and copying within 60 days at the Freedom ofInformation Public Reading Room; Room 1E-190; Forrestal Building; 1000 Independence Avenue, SW, Washington, DC, between 9 a.m. and 4
p.m., Monday through Friday, except Federal holidays. Issued at Washington, DC onJuly 9, 2002. Rachel M. Samuel, DeputyAdvisoryCommitteeManagement Officer. [FR Doc. 02-17636 Filed 7-12-02; 8:45 am]

BILLING CODE 6450-01-P

DEPARTMENT OF ENERGY

Office of Energy Efficiency and Renewable Energy
[Docket No. EE-DET-02-001]

Building Energy Standards Program: Determination Regarding Energy Efficiency Improvements in the Energy Standard for Buildings, Except LowRise Residential Buildings, ASHRAE/ IESNA Standard 90.1-1999.

AGENCY: Office ofEnergy Efficiency and Renewable Energy, Department of Energy (DOE).

ACTION: Notice.

SUMMARY: TheDepartment ofEnergy (DOE or Department) today determines that the 1999 edition ofthe

### Energy StandardforBuildings, ExceptLow-Rise ResidentialBuildings, American Society ofHeating, Refrigerating and AirConditioningEngineers (ASHRAE) IlluminatingEngineering Society of North America (IESNA) Standard 90.1- 1999, (Standard 90.1-1999 or the 1999 edition) would achieve greater energy efficiency inbuildings, except low-rise residential buildings, than the 1989 edition (Standard 90.1-1989 or the 1989 edition). As a result ofthis positive determinationregarding Standard 90.1- 1999, each State is required to certify that it has reviewed and updated the provisions ofits commercialbuilding coderegarding energy efficiency to meet

or exceed Standard 90.1-1999 for any "building" within the meaning of Section 303(2) ofthe Energy Conservation and Production Act, as amended. This Notice provides guidance to States on Certifications, and Requests for Extensions ofDeadlines for Certification Statements.

DATES: Certifications and Requests for Extensions ofDeadlines, with regard to Standard 90.1-1999, are due at DOE on

or beforeJuly 15, 2004.

ADDRESSES: Certifications, or Requests for Extensions ofDeadlines shouldbe directed to the Assistant Secretary for Energy Efficiency and Renewable Energy, Office ofBuildingTechnology Assistance, EE-42, 1000 Independence Avenue, SW., Washington, DC. 20585- 0121. Envelopes or packages should be labeled, "State Certification of Commercial BuildingCodes Regarding Energy Efficiency." FOR FURTHER INFORMATION CONTACT: Jean J. Boulin, U.S. Department ofEnergy, Office ofEnergy Efficiency and Renewable Energy, Forrestal Building, Mail StationEE-2K, 1000 Independence Avenue, SW., Washington, DC 20585- 0121, Phone: 202-586-9870, FAX: 202- 586-1233.

SUPPLEMENTARY INFORMATION:
I. Introduction

A. Statutory Requirements B. Background 1. Publication ofStandard 90.1-1999 2. Workshop and Comments on Analysis

Methodology 3. Comments onPreliminary Quantitative

and Textual Analyses C. Summary ofthe Comparative Analysis 1. Quantitative Analysis 2. Detailed Textual Analysis D. Determination Statement II. Results ofQuantitative Analysis III. Discussion ofDetailed Textual Analysis

A. Lighting and Power
1. Interior LightingPower Exemptions 2. Exterior LightingPower 3. Lighting Controls-Interior 4. Ballast Efficacv Factor 5. Exit Signs 0
6. InteriorLightingPower-Whole

Building 7. Interior LightingPower-Space-BySpace 8. End Use Metering 9. Transformers
10. Motors B. BuildingEnvelope 1. Air Leakage 2. Insulation Installation 3. Allowance for Speculative Buildings 4. Envelope Thermal Transmittance in

Cold Climates 5. Skylight Thermal Transmittance and

Solar Heal Gain 6. Slab-On-Grade and Below Grade Wall

Insulation 7. RoofThermal Transmittance 8. Floors Over Unconditioned Spaces 9. OpaqueWall Thermal Transmittance
10. Window Thermal Transmittance and

Solar Heat Gain 11. Opaque Doors C. Mechanical Equipment and Systems 1. Load Calculations and Sizing 2. Separate air distribution systems 3. Temperature Controls 4. Off-Hour Controls and Setback 5. Dampers 6. Humidity Control 7. Radiant Heating 8. Ventilation 9. Pipe and Duct Insulation 10. Heat Recovery 11. Completion Requirements 12. Simultaneous Heating and Cooling

Controls 13. EconomizerControls 14. Fan System Design Criteria 15. Pumping System Design
16. Temperature Reset Controls 17. Hot Gas Bypass Restriction 18. Heating Ventilation and AirConditioning Equipment 19. ServiceWater Heating Equipment

Efficiency

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices 46465

20. Service Water Heating Controls D. Energy Cost Budget E. Conclusion About Detailed Textual

Analysis IV. Filing Certification Statements with DOE

A. Review and Update B. Certification C. Request for Extensions D. Submittals Appendix A. Description ofProposed Analysis Appendix B. Description ofthe Quantitative Analysis
I. Analysis Methodology IL Simulation Input Characterization

A. Envelope B. Lighting 1. LightingPower-1989 Edition 2. Lighting Power-1999Edition C. Mechanical Equipment 1. Cooling Equipment 2. Space Heating Equipment 3. Economizers 4. Service Water Heating Equipment D. Aggregation ofResults

I. Introduction



### A. StatutoryRequirements

Title III ofthe Energy Conservation and ProductionAct (ECPA), establishes requirements for the BuildingEnergy Efficiency Standards Program (42 U.S.C. 6831-6837).

ECPA provides that whenever the Standard 90.1-1989, or any successor to that code, is revised, the Secretary must make a determination, not later than 12 months after such revision, whetherthe revised code would improve energy efficiency in commercial buildings and must publish notice ofsuch determination in the Federal Register (42 U.S.C. 6833 (b)(2)(A)). The Secretary may determine that the revision of Standard 90.1-1989, or any successor thereof, improves the level ofenergy efficiency in commercialbuildings. If the Secretary makes a determination that the revised standard will improve
energy efficiency in commercial buildings, then not later than two years after the date ofthe publication ofsuch affirmative determination, each State is required to certify that it has reviewed and updated the provisions ofits commercial building coderegarding
energy efficiency with respectto the revised or successor code for any "building" within the meaning of Section 303(2) ofECPA. The State must include in its certification a demonstration that the provisions ofits commercial building code, regarding
energy efficiency, meet or exceed the revised standard (in this case, Standard 90.1-1999) (42 U.S.C. 6833(b)(2)(B)(i)). Ifthe Secretary makes a determination that the revised standard will not improve energy efficiency in commercial buildings, State commercial codes shall meet or exceed Standard 90.1-1989 or the last revised standard for whichthe Secretary has made a positive determination (42 U.S.C. 6833(b)(2)(B)(ii)).

ECPA also requires the Secretary to permit extensions ofthe deadlines for the State certification ifa state can demonstrate that it has made a good faith effort to comply withthe requirements ofSection 304(b) and that it has made significant progress in doing

so (42 U.S.C. 6833(c)).



### B. Background

1. Publication ofStandard 90.1-1999

The American Society ofHeating, Refrigerating and Air-Conditioning Engineers (ASHRAE) and the IlluminatingEngineering Society of North America (IESNA) approved the publication ofthe 1999 edition of 

### Energy StandardforBuildings Except Low-rise ResidentialBuildings, inJune 1999. Several appeals to this decision

were heard and subsequently rejected and the 1999 edition was published in February 2000.

The Standard was developed under American National Standards Institute approved consensus standard procedures. The American Society of Heating Refrigerating andAirConditioningEngineers submitted the standard to the AmericanNational Standards Institute (ANSI) for designation as an approved ANSI standard. In December 2000, after several appeals by the American Gas Association, the 1999 edition of Standard 90.1 was approved as an American National Standard.

2. Workshop and Comments on Analysis Methodology

In arriving at a determination, the Department first reviewed all significant changes between the 1989 edition and the 1999 edition ofStandard 90.1. Standard 90.1 is complex and covers a broad spectrum ofthe energy related components and systems in buildings ranging from simple storage buildings to complex hospitals and laboratories. The size ofbuildings addressed range from those smaller than single family homes
to the largest buildings in the world. The approach to development ofthe standard changed from that used for the 1989 edition, as did the scope and the
way components were defined. We concludedthat a simple comparison of the two editions would not be possible. Therefore, we decided to hold a public workshop and seek public comment on

ourproposed analysis methodology. On February 8, 2000, we proposed a methodology, announced a public workshop, and sought public comment. 65 FR 6195. On February 17, 2000, we held a workshop to obtain comment on the approach we proposedto use. See the summary ofthe proposed approach inAppendix A.

We requested comments and/or data concerning issues relating to the comparative analysis ofStandard 90.1- 1989 and Standard 90.1-1999. We especially expressed interestin any comments or data regarding: (1) The

sevenbuildingtypes selected for analysis; (2) the 11 representative climate locations proposed for the analysis; (3) the frequency ofuse of alternative paths to compliance in building standards (e.g., space-by-space

versus wholebuilding lighting power allowances); (4) new non-residential building construction data by state or

census division andbuildingtype; (5) data to quantify the impact ofStandard 90.1-1999 on additions and renovations
to existing buildings; (6) the prevalence ofthe semi-heatedbuilding envelope subcategory in thebuildingtypes proposed for analysis; and (7) specific
comments onthe preliminary energy savings analysis distributed inJune 1999.

We received comments from American Electric Power, the American Gas Association, theEdisonElectric Institute, GARD Analytics, Inc., the New Buildings Institute, and Virginia Power.

American Electric Power, theEdison Electric Institute, and Virginia Power recognized that, given the numerous assumptions required to simulatethe potential impact ofthe new standard, reasonable minds could differ over both the specific model employed and over the assumptions used inthose models. For thatreason, they cautionedthe Department against becoming involved in a lengthy process aimed at reconciling all approaches. They expressed beliefinthe results ofthe initial analysis that the 1999 edition would save energy across a broad section ofcommercial buildings. We recognized their cautions about the complexity ofthe problem and magnitude ofalternative compliance approaches inthe standard. However,

we felt obligated to extendthe analysis

as far as feasible.

The New Buildings Institute supported the proposed methodology for the purpose ofa simple yes/no determinationbut felt that the proposed methodology was inadequate for determining energy savings estimates associated with using Standard 90.1- 1999. Here too, we recognized the difficulty ofabsolute quantification of savings, and make no such claim for the

### 46466 

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002 /Notices

analysis on whichthis determination relies.

The American Gas Association argued that the Department should rely solely

on quantitative estimates ofenergy savings as a means ofcomparing the two editions ofStandard 90.1 and minimize the use ofqualitative comparisons. We tend to agree with the previous
comments from American Electric Power, the Edison Electric Institute, and VirginiaPower, and the New Buildings Instituteregarding the details ofthe analysis, and concludedthat it was necessary to note changes that individually, or in net, result in increased energy efficiency, even where they could not be accurately quantified. We believe that States canuse this information when upgrading their energy codes.

The American Gas Association also expressed a strong beliefthat the analysis shouldbe based onthe minimumrequirements ofeach edition and not on typical design and construction practice. In the area of heating, ventilating and air-conditioning and water heating equipment, the American Gas Association expressed the opinion that the Department should include analysis ofequipment market share impacts in its analysis. It also expressed the opinion that the analysis be based on consensus forecasts of commercial construction activity, rather than on existing building stock, and use these forecasts as thebasis for energy consumption calculations. It was concernedthat the Department select the correct version ofthe 1989 edition for thebaseline and recommended that the baselinebe the 1989 edition plus all addendato that edition, up to the publication ofthe 1999 edition. Finally, the American Gas Association expressed the beliefthatthe analysis must include

a cost-effectiveness and economic justification review.

We agree that the analysis shouldbe based on the minimumrequirements of each standard but in assessing the impact ofthose requirements, we believe that assessment shouldbe based

on a realistic estimate ofwhat is being built. We believe that we have done this in our analysis.

We do notbelieve it is necessary for the Departmentto perform a quantitative analysis ofthe likely effects ofStandard 90.1-1999 on fuel and equipmentmarket shares in order to support a conclusion regarding the likely net energy savings that would result. Without performing a quantitative analysis ofthe possible effects on fuel or equipment market shares, there are several reasons why the Department has concluded that these effects are likely to be insignificant. First, since Standard 90.1-1999 places the same requirements on buildings with different types ofheating or cooling equipment (and this was also
true ofprevious ASHRAE standards), the impacts ofthe standard on most building costs should be identical, regardless ofthe type ofenergy or equipmentused. Second, ifthe comparative costs and market shares of equipmentused inbuildings covered by the ASHRAE standard are influenced by other administrative actions taken by theDepartment ofEnergy or other government agencies, any effects on fuel market shares thatresult from such other actions cannotproperly be attributed to the ASHRAE standardthat is the subject oftoday's determination. Finally the choice offuels and equipmentby new building designers, builders, and owners is affected by many factors, only a few ofwhich are related to the comparative first costs of the equipment andbuilding systems involved. In cases where comparative equipment and system costs are a significant factor in fuel choice, the small changes in these costs that might be attributable to the ASHRAE 90.1- 1999 building standard are very unlikely to significantly affect market shares or the resulting energy savings.

We considered using what the American Gas Association referred to as

consensus forecasts ofcommercial construction activity, rather than data

on the existing building stock in our analyses. We concluded, however, that available forecasts are not really

consensus forecasts. These latter forecasts are extremely short term in perspective, andreflect that the construction market is likely to remain volatile over the intermediate term. We have therefore used the new construction square footage data from 2001-2010, extracted from the Energy Information Administration's National Energy Modeling System, as the basis for our analysis.

Furthermore, AGA believes that each addendum shouldbe treated as a revision to the standard, thus requiring DOE to issue a determination for each addendum pursuantto Section 304(b)(2) ofECPA, as amended, 42 U.S.C. 6834 (b)(2). AGA has also questioned the appropriateness ofthe baseline DOE used when comparing the revised ASHRAE Standard 90.1-1999 with its predecessor, ASHRAE Standard 90.1- 1989, in order to determine whether the

newASHRAE Standard improves
energy efficiency. AGA would have DOE use ASHRAE Standard 90.1-1989 with all ofthe addenda up until the publication ofASHRAE 90.1-1999 for the comparison.

Section 304(b)(2) ofECPA, as amended, which applies to commercial building code updates, requires that whenthe provisions ofASHRAE Standard 90.1-1989, or any successor standard, are revised, the Secretary shall, not later than 12 months after the date ofsuch revision, publish a notice in the Federal Register, with its determination as to whether the revised standard will improve energy efficiency in commercialbuildings. Once the Secretary issues a determination, States have two years, with possible extensions for good faith efforts, to comply withthe certification requirements in Section 304(b)(2).

DOE interprets the language in Section 304(b)(2) to mean that when a comprehensiverevision ofthe ASHRAE Standard is published, which inthis

case is ASHRAE Standard 90.1-1999, then thatrevised or successor standard triggers the Secretary's obligation to issue a determination as to whetherthe revised standard improves energy efficiency. This determination is made by comparing therevised or successor standard to the last predecessor standard.

While it is true thatthe addenda process is part ofthe ongoing maintenance ofthe standard and thus continually modifies the existing standard over time, it wouldbe an unreasonable reading ofthe statute to categorize each addendum in this maintenance process as a "revised or

successor standard" withinthe meaning ofSection 304(b)(2), so as to require a determination by the Secretary. Such an interpretation ofthe statute would put

an unreasonable burden both on the States and DOE. For the States, a determination by the Secretary requires

some State action, and whatis required depends upon whether the Secretary issues an affirmative or a negative determination. Ifthe Secretary were required to issue a determination after each addendum was published, the States wouldbe constantlyrequired to change their codes. This would affect the stability and certainty ofState commercial building codes. DOE believes that Congress could not have intended this result. Therefore, DOE concludes thatthe statute only requires

a determination by the Secretary when there is a comprehensive revision to the standard.

With respect to the baseline for comparing the energy efficiency of revised ASHRAE Standard 90.1-1999 with its predecessor, ASHRAE Standard 90.1-1989, DOE's position is that the appropriate baseline is ASHRAE

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices 46467

Standard 90.1-1989 with addendain effect at the time EPACT was enacted. Sincethis is the first determination for commercialbuilding codes since ECPA

was amendedby EPACT on October 24, 1992, it is reasonable to interpret section 304(b)'s reference to ASHRAE Standard 90.1-1989 to includethe addenda in effect on the date ofenactment. DOE interprets the statuteto require a comparison ofthat version ofASHRAE 90.1-1989 (and not any subsequent addenda) withASHRAE Standard 90.1- 1999. IfDOE were to adoptthe AGA position and include all ofthe intervening addendato ASHRAE Standard 90.1-1989 up to the adoption ofASHRAE 90.1-1999 inthe baseline, it wouldrender DOE's determination almost meaningless. That is, ifall ofthe post-enactment addendato ASHRAE Standard 90.1-1989 were included in the baseline, the real energy efficiency improvements (assumingthere are any) oftherevised standard wouldbe reflected inthe baseline. A comparison ofa revised standard andthe previous standard (under such an interpretation) would always show little, ifany, energy efficiency gains. Thatwould defeat the statute's purpose ofrequiring DOE to comparethe energy efficiency ofrevised standards (i.e., comprehensiverevisions ofASHRAE Standard 90.1-1989 or
successor standards) with the prior or last standard.

AGA and the Natural Resources Defense Council argue that DOE has a statutoryresponsibility to determine whetherthe revised standard would improve energy efficiency in commercialbuildings and also whether all new energy efficiency measures are technologically feasible and economicallyjustified. (Letter dated April 12, 2000, from the American Gas Association andthe Natural Resources Defense Council, signedby Charles H. Fritts and Katherine Kennedy, to Dan W. Reicher, Assistant Secretary Energy Efficiency and Renewable Energy) They contend that DOE is required to conduct cost-effectiveness and economic justification analyses as part ofthe process in making its determination concerningASHRAE Standard 90.1- 1999 pursuantto Section 304 ofECPA,

as amended. These who commented believe thatthe statutory scheme, including Section 307, entitled "Supportfor Voluntary BuildingEnergy Codes," supports its argument.

The statutory language in Section 304(b) states that the Secretary is required to make a determination as to whether any successor standardto ASHRAE Standard 90.1-1989 will improve energy efficiency. The Secretary mustpublish a notice ofthis determination in the Federal Register. The language does notrequire that DOE perform an independent economic analysis as part ofthe determination process. As a matter offact, Section 304(b) omits any reference to language concerning economicjustification.

However, Congress was concerned thatthe technological feasibility and
cost effectiveness ofthe Voluntary BuildingEnergy Codes be considered. Section 307 clearly requires DOE to participate in theASHRAE process and
to assist in determiningthe cost effectiveness and technical feasibility of the ASHRAE standard. Italso requires DOE to periodically review the economic basis ofthe voluntary building energy codes and participate in the industry process for review and modification, including seeking adoption ofall technologically feasible and economicallyjustified energy efficiency measures.

Unlike Section 307 which specifically includes language concerning economic justification, Section 304 omits any reference to economicjustification. Itis generally presumedthat Congress acts intentionally and purposefully where it includes particular language in one section ofa statutebut omits it in another section. 

### See Bates v. 

### United States, 522 U.S. 23, 29-30 (1997). Accordingly, the statutory scheme
cannotbe read to require an economic analysis as part ofthe determination process in Section 304(b).

The fact thatthe Section 304 determination process does notrequire the Secretary to perform an economic analysis does not diminish the importance that the ASHRAE standards be technologically feasible and economicallyjustified. However, it appears that Congress assumed that these concerns would be worked out by stakeholders, withDOE participating in the ASHRAE process itself. The language ofSection 307 clearly delineates DOE as one participant in the process, not the ultimate decision maker ofthe ASHRAE standard or successor revisions.

Accordingly, for all ofthese reasons, DOE has determined that it is not required to perform an economic analysis as part ofits determination process in Section 304 ofECPA, as amended.

A number ofthe GARD Analytics
comments were incorporated into our analysis. They include: (1) Extending the aggregation to cover buildings with different window area fractions instead ofdoing a sensitivity analysis; (2) use of the Alternate Component Packages tables in the 1989 edition's envelope section, to make it easier to identify the criteria which shouldbe used in modeling the 1989 edition's envelope criteria; and (3) eliminating estimates of equipment operating hours in weighting equipmentefficiency. In addition, we estimated efficiency improvement for cooling equipment and incorporated estimates ofboth single and three phase unitary cooling equipment less than 65,000 Btu per hour, shippedto commercial buildings.

GARD Analytics suggested we use specific prototype buildings as it did in its analysis, instead ofour scaling approach. Italso urged us to select specific building sizes for analysis. We believe thatby using a scaling approach,

we canbetter assess the impact of building envelope changes. Scaling permits us to better account for the actual ratio ofbuilding wall areato floor

area in a population ofbuildings, rather than assume some fraction ofthe building population has a single size and geometry and thatthose characteristics hold for all buildings in thatfraction ofthebuilding population. The size selection ofthe prototype used for scaling is nearthe median square footage for mostbuilding categories. Using abuilding size thatis close to the medianhelps ensurethatthe characterization ofsecondary effects, such as the transitional performance of thebuildingunderthermostat setback conditions, is captured in a mannerthat is reasonable for the majority ofthe building population.

GARD Analytics also commented on
ouruse ofa one-to-one aspect ratio (the ratio oflength to width ofabuilding) in the prototype. While we use an aspect ratio ofone-to-one in the prototype simulation, to make the simulation orientation neutral, our scaling process does includetypical aspectratios for all building types to correctly determine theratio ofperimeter and core areas in thebuildingpopulation. GARD Analytics commentedthat the use of scaling does not allow the use of different lighting power densities for differentbuilding sizes, as are shown in the 1989 edition. In our approach the weighted average lighting power density

over all Commercial BuildingEnergy Consumption Survey building sizes was used as thebasis ofour simulation of the 1989 edition's requirements. This correctly characterizes the average lighting improvement over all building sizes.

GARD Analytics also had a number of
comments on our proposed methodology. It suggested that selection ofbuilding types by baseline energy use

was less correct than ifit was done by square footage. We disagree. The purpose ofselection by energy use, as

### 46468 

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices

opposed to square footage, is to select the buildingtypes that will be most significant interms ofnational energy
use. We believe that as the number of buildingtypes used is increased, the set ofbuildings types selected by either method will converge to the same set.

GARD Analytics also questioned elimination ofthe in-patient health care facilities category from our analysis and statedthat available hospital models couldbe used. In-patient health care facilities are perceived to have high thermal loads and equipment loads withinthe health care category. Given the requirements ofthe 1999 edition, inclusion ofthis category would increase estimates ofenergy savings. However, we consideredtherelatively low ranking ofin-patienthealth care buildings interms ofnet energy use and the modest level offuture in-patient health care new building growth. This reduced the importance ofmodeling this category. Finally, we did not have confidence inthe representative nature ofavailable in-patienthealthcare models. We therefore chose not to simulatethisbuildingtype separately in

our analysis. We believe that not doing

so resulted in a conservative estimate of the energy savings attributable to the 1999 edition.

GARD Analytics also commentedthat

we should use the operating schedules and loads from the 1999 edition for the analysis. Our selected schedules are based on accurate measured data and

we believe thatthey are at least as representative oftypical buildings as those in the 1999 edition.

GARD Analytics commented onthe

use ofsupplemental lighting power allowances. We concludedthat the most appropriate lighting power allowances for our quantitative comparison were the whole-building lighting requirements. We commented on the space-by-space requirements andthe impact ofthe supplemental lighting power allowances in our detailed textual analysis.

GARD Analytics commented that we should use the maximum fan power allowances underboth standards in our comparison. However, since the maximum fan power allowances are effectivelythe same inboth standards, and are notbelievedrepresentative of typical building design, we chose to use

a more typical fan power usage andthus show a more realistic level ofenergy usage for buildings underboth standards. Utilizing the maximum fan power would increase internal building loads, decrease heating loads and lower buildingbalance temperature. The impact wouldbe to increase absolute energy savings over the 1989 edition. DOE2.1 and BLAST (Building Loads and System Thermodynamics) are both buildingenergy analysis computer programs. GARD Analytics commented thatDOE shoulduse DOE2.1, instead of BLAST, as the basis ofthe energy simulations. They state that DOE2.1 is

more commonly used by building designers and that further development ofBLAST is being phased out. DOE disagrees with the comment since BLAST forms thebasis ofthe Department's new, improved simulation tool, Energy Plus, and since DOE is actually phasing out supportfor DOE2.1.

GARD Analytics commented thatwe should use the most stringent compliance path on whichto do our quantitative analysis. The Department considered this but selected the prescriptive compliance paths on which
to base its quantitative analysis, since it is those paths for which specific requirements can be accurately identified for "prototype" buildings. Selecting representative requirements from the variable requirements in the other pathsbecomes highly speculative. We have addressed requirements from these other compliance paths inthe detailed textual analysis.

GARD Analytics commented on the selection ofclimates andregional weighting for our analysis. Itfelt that DOE's strategy to select the cities (which represent sets ofclimate data) is suboptimal and ignores the real effect of the standard having different criteria in different climates. We have reviewed

our selection ofclimates and methodology and believe it to be entirelyrepresentative and appropriate for this analysis. GARD Analytics also commentedthat it was unnecessary to

use sub-census regions in our aggregation approach. However, wefeel that the use ofsub-census regions is necessary to correctly represent the variation inenergy costs inthe western U.S. We believe that it introduces no additional error in theremainder ofthe analysis.

GARD Analytics made a number of
comments that we should do more detailed analyses. Examples offurther analysis suggested by GARD Analytics included: state by state comparisons of the standards, the development of lighting power usage using the space-byspace method, inclusion ofroom air conditioners inthe development ofthe cooling equipment efficiencies, the use ofbelowground building spaces in the comparison, and the use ofmarginal energy costs. We reviewed these comments, but concludedthat the limited data available for describing building populations and weighting the results ofmore simulations would not result in a more accurate conclusionto

our analysis. A number ofthese
comments are addressed in our detailed textual analysis.

3. Comments on Preliminary Quantitative and Textual Analyses

As a matter ofpolicy to further the determination process, we sought further comments on the application of the methodology and the validity of preliminary conclusions posted on our web site. A summary ofcomments and responses on common topical issues, regarding the application ofthe methodology and the preliminary conclusions, follows below. For detailed responses to the comments received, see 

### Response to Comments on Preliminary Analyses SupportingDOE's Determination Regarding Standard 90.1-1999, which is part ofthe administrative record for this Determination Notice. This document may be viewed at the DOE Freedom of Information Reading Room, U.S. Department ofEnergy, Forrestal Building, Room lE-190, 1000 IndependenceAvenue S.W., Washington, D.C. 20585, (202) 586- 3142, betweenthe hours of9:00 a.m. and4:00 p.m., except Federal holidays,

or a copy may be obtained from the Department from the contactperson identified above.

We received 12 comments, two from design practitioners (G. Johnson and Kay), four from States or code officials (Lloyd, Weitz, Cowen, Hogan), one representing States in a region (Coakley), onejointly from the two professional societies sponsoring the

consensus process that developed the Standard (WolfandTimmings), one from a public interest group (Goldstein),

one from an energy code consultant (J. Johnson), andtwo representing the gas industry (Ranfone and Hemphill). Two who commented (Johnson and Kay) did
not comment on the analysis. One of those who did not comment on the analysisjoined four others who commented that the Department was late in making its determination and that the delay was hampering the Region's or State's updating ofits energy codes (G. Johnson, Lloyd, Coakley, and Weitz). Ofthe nine commenting on the analysis, seven felt the analysis was well done or reasonable and agreed with the results. (Lloyd, Cowen, Coakley, Weitz, Wolfand Timmings, Goldstein andJ. Johnson). One who commented suggested a change and wanted some further analysis done (Hogan), and another who commented had 35 detailed comments (Hemphill).

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices 46469

Five complained aboutthe amount of time it is taking the Department to make

a determination Uohnson, Cowen, Coakley, Weitz, and Goldstein). They statedthatthe delaywas adversely impacting States ability to update their energy codes and gain energy and greenhouse gas benefits.

Five commentedthat they interpreted the analyses to conclude thatthere wouldbe a net positive increase in commercial building energy efficiency and agreed with the conclusion for a positive determination. (Coakley, Lloyd, Weitz, WolfandTimmings, Goldstein, andJ. Johnson). Three ofthese further commentedthatthe analyses were reasonable. One (Weitz) expressed the opinionthat this is an achievable standard and indicatedthat Massachusetts has already adopted a
new construction energy code based on the 1999 edition. However, one (Ranfone) commentedthat DOE should
not complete its determination, until such time as an analysis is done to determine whether all new energy efficiency measures are technologically feasible and economicallyjustified, a commentDOE previously addressed above.

One (Hogan) commented, and we agree, that thebuilding envelope criteria for the "lodging" category in our quantitative analysis shouldbe taken from the "residential" column in the tables in AppendixBofthe 1999 edition, rather than from the "nonresidential" category, since the only change was inthe opaque envelope. We have revised the analysis accordingly.

Hogan also commentedthat the quantitative analysis shouldbe expandedto include all energy usedin buildings, including elevators, exterior lighting for entrances and facades, parking lighting, and parking ventilation, andbe expanded to differentiate part-load operation between fan systems with and without variable frequency fans. Data on buildings andbuilding component characteristics are insufficient to accurately includethese in our analysis. However, each is addressed inthe detailed textual analysis, except for elevators which are not addressed in eitherthe 1989 or 1999 editions of Standard 90.1.

One who commented (Hemphill) submitted 35 detailed comments on our analyses. We agreed in whole or in some part with eleven ofthese comments and have accordingly made changes or clarifications to ourtextual analysis. These eleven include comments on: exterior lighting power, interior lighting power-space-by-space, envelope air leakage, floors over unconditioned spaces, opaque wall thermal transmittance, opaque doors, load calculations and sizing, off-hour controls and setbacks, simultaneous heating and cooling controls, airconditioning equipment, and non-code language. In several cases, while we disagreed with comments, we further clarified our rationale, as noted below.

Six comments received had to do with differing interpretations ofthe standard. These included comments havingto do with lighting power exemptions, lighting integral to equipment, transformers, transportation systems, energy management systems, and the energy costbudget compliance path. On review, we disagreed with the interpretations presented in the
comment and made no change. For example, in the case ofenergy management systems, they are recommended not required, as implied in the comment, inbuildings over 40,000 square feet in the 1989 edition. Inthe 1999 edition, energy management systems are not omittedbut are addressed differently, under controls. In the case ofthe comment on the energy cost budget compliance path, we believe thatboth editions establish a baseline of requirements from the prescriptive compliance approach and require the energy cost ofthe design to be equivalent or less thanthebaseline. We therefore believe that in each edition the energy costbudget compliance path criteria are roughly equivalent to the prescriptive compliance path.

The comments ofHemphill, which related to transformers, transportation systems, and energy management systems, suggested that we might have missed some differences betweenthe
two editions ofthe standard. On inspection we found thatwe had missed

some differences. Therefore we have added analysis that addresses the subdivision ofelectric power feeders and provisions for check metering of loads.

Eight comments received hadto do with differing opinions on appropriate approaches to the textual analysis. These included comments on the subjective nature ofthe analysis ofthe envelope section, exit signs, the use of the prescriptive compliance path and
not the performance paths in the analysis, our conclusions on the lighting power exemptions, window thermal transmittance and solar heat gain, temperature reset controls, and heating equipment. Four ofthese comments provide no suggestion ofan alternative approach. We believe that our approach in the textual analysis provides useful information to states which will adopt the standard, even ifthe changes cannot be fully quantified. In the case ofexit signs, and heating equipment, we did
not agree that, where there were no criteria inthe 1989 edition and there

were criteriainthe 1999 edition, we could not or shouldnot project savings. No changes were made inresponse to these comments except for the comment

on windowthermal transmittance, where explanatory text was addedto the textual analysis.

Six other comments werereceived with which we disagreed butwhich led

us to adding explanatory text to the textual analysis. This was done inthe analysis relative to speculative building envelopes, envelope thermal transmittance in cold climates, slab on grade and below grade wall insulation, roofthermal transmittance, temperature controls, and pipe and duct insulation. One ofthese, the comment on pipe and duct insulation appeared to be a misinterpretation ofwhat we wrote. In addition, more analysis was done on the subject ofroofthermal transmittance.

Five comments appear to have been a misinterpretation ofour written analysis. These comments concerned parts ofourwholebuildinginterior lighting power criteria, interior lighting controls and separate air distribution systems, radiant heating, and service
water heating equipment. In the case of the comment on interior lighting controls, there are also opinions stated without support. Review ofour explanations did not suggest any change.

One (Hemphill) argued thatthere was
no difference in scope between the two editions. However, four others (Coakley, Weitz, Wolfand Timmings, and Goldstein) all recognized the expansion ofthe scope ofthe 1999 editionto renovations ofexistingbuildings. We agree withthe latter majority opinion including those representing the organizations sponsoring the two editions. We note that through the mid 1990s the American National Standards Institute recognized the ASHRAE Standard 100 series, that explicitly addressed existing buildings. Under American National Standards Institute policy, two standards (Standard 90.1- 1989 and ASHRAE Standard 100) could
not address existing buildings.

One (Hemphill) interpreted our analysis regarding increasing the scope ofthe 1999 editionto existing buildings
to imply that the increased energy efficiency could approach 50 percent of the energy use reduction from new construction and expressed the opinion that there was absolutely no basis for this assertion, and that the implication

was wholly inappropriate. Another

### 46470 

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices

(WolfandTimmings) commented onthe subject that industry estimates indicate that at least 60 percent ofheating and cooling equipment sales are for replacement markets, and only 40 percent for newbuildings, but did not provide a source for this estimate. We continueto believe that it is difficult to quantify the energy efficiency impact of the change in scopeto include existing buildings. We will not attempt to estimate the impact ofthis change. Today's determination does not address

or rely on this difference.

C. 

### Summaryof the Comparative Analysis

We carried outboth a broad quantitative analysis and a detailed textual analysis ofthe differences betweenthe requirements andthe stringencies in the 1989 and the 1999 editions.

1. QuantitativeAnalysis

The quantitative comparison of
energy codes was done using wholebuilding energy simulations ofbuildings builtto each standard. We simulated

sevenrepresentative building types in 11 representative U.S. climates. Only differences between newbuilding requirements were considered inthis quantitative analysis. The simulations

were based on a 15 zone building prototype used in previous DOE building research. The simulated Energy Use Intensities (EUI) for each zone were scaledto correctly reflect variations in building size and shapes for each representative buildingtype. Energy use intensities developed for each representative buildingtype were weightedbytotal national square footage ofeachrepresentative building typeto provide an estimate ofthe difference between the national energy

use inbuildings constructedto both editions. A more detailed explanation is located in AppendixBto this notice.

The quantitative analysis ofthe
energy consumption ofbuildingsbuilt
to the 1999 edition, compared with buildingsbuiltto the 1989 edition for

newbuildings, indicates national source energy savings ofapproximately 6.4 percent ofcommercial building energy consumption. Site energy savings are estimatedto be approximately 4.5 percent. These figures represent a conservative estimate ofenergy savings for newbuildings. 2. Detailed Textual Analysis
We also performed a detailed analysis ofthe differences between the textual requirements and stringencies ofthe
two editions ofStandard 90.1 concerningthe scope ofthe standard, the building envelope requirements, the building lighting and power requirements, and the building mechanical equipmentrequirements. The detailed textual analysis addresses

a number ofdifferences that, while very real, we could not accurately or reliably quantify because oflack ofreliable information aboutthebuilding stock andthe incorporation ofvarious components and equipment in various parts ofthe country. Therefore, the detailed textual analysis makes no attempt to quantify the differences between the 1989 and 1999 editions.

The emphasis ofour detailed requirement and stringency analysis

was on differences between the envelope, lighting, and mechanical sections ofboth editions ofStandard 90.1.

The lighting requirements comparison focused on the impactthe different lighting requirements have on lighting energy use, as well as onbuilding loads. The comparison looked separately at the whole building and space-by-space lighting requirements inboth standards in a variety ofcommercial building types, as well as examined the effect of any "additional lighting power allowances." Italso looked at controls.

The mechanical requirements comparison looked at equipment efficiency requirements and system design requirements. The system design requirements affect the system efficiency, system thermal load, and also had some direct energy impacts.

In comparing the envelope requirements, we madejudgements of relative stringency and frequency of

occurrence ofcomponents.

Each standard has multiple ways to demonstrate compliance. We did not perform a detailed comparison ofthe relative stringency ofthe alternate paths internal to a single standard or between standards. The large number ofvariables among the alternative compliance paths made such a comparison prohibitive to undertake. Further, we knew ofno data

on whichto base the selection of representative requirements for such an analysis. Assignment ofrequirements would have been arbitrary. Rather we focused on the prescriptive compliance paths ineach section, which we believe represent the most common approach to usingthe standard in question for most buildings.



### D. Determination Statement

The Department's review and evaluation found thatthere are significant differences betweenthe 1989 edition andthe 1999 edition. Our overall conclusion is that the 1999 edition will improve the energy efficiency ofcommercial buildings, even though in certain limited instances stringencies for some requirements are reduced. However, we found a number ofchanges in textual requirements and stringencies that will decrease energy efficiency. Overall, we concludedthe changes intextual requirements and stringencies are "positive," inthe sense that they will improve energy efficiency in commercial construction. Our quantitative analysis shows, nationally,

newbuilding efficiency should improve by about sixpercent, looking at source energy, andby about four percent, when considering site energy. DOE has therefore concludedthat the 1999 edition shouldreceive an affirmative determination under Section 304(b) of the Energy Conservation and Production Act for "buildings" withinthe meaning ofSection 303(2).

II. Results ofQuantitativeAnalysis

Tables 1 and 2 showthe aggregated energy use and associated energy savings bybuilding type for the seven categories analyzed and on an aggregated national basis for the 1989 and 1999 editions, respectively. See Appendix B for an explanation ofthe methodology we used. For each edition the buildingfloor area weight is usedto calculate thebuilding energy or cost use intensity. The electric and gas building energy use intensity is presented for each type analyzed with electric predominating in all types. Site energy
use intensities ranges from more than 137 thousand Btu per square foot annually for the Foodbuilding type to

more than 18 thousand Btu per square foot annually for theWarehouse building type. Source energy use intensities have similarranges as site
energy ranges butvary in quantitative order from site energy intensities. (Lodging and Office rank 4th and 5th respectively for site energy, while for

source energytheirranking is reversed, 5th and 4threspectively.). Building energy cost intensities are also presented.

### Federal 

### Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices

TABLE 1.-ESTIMATED ENERGY USE INTENSITY BY BUILDING TYPE-1989 EDITION

Building type

Assembly

.......................................................................... Education

......................................................................... Food

................................................................................. Lodging

............................................................................ Office

................................................................................ Retail

...........................:

.................................................... Warehouse

....................................................................... National

............................................................................ Building type floor

area weight

0.068 0.218 0.027 0.079 0.190 0.246 0.173 Electric

61.55 35.65 101.60 42.80 49.85 57.14 10.43 43.36 Whole building energy use intensity (kBtu/sf-yr or $/sf-yr)

Gas Site EUI Source EUI

32.18 93.73 231.78 18.86 54.50 134.47 35.52 137.12 363.04 17.61 60.41 155.88 5.61 55.45 165.00 3.95 61.09 186.39 8.19 18.62 42.32 12.09 55.44 151.52

TABLE 2.-ESTIMATED ENERGY USE INTENSITY BY BUILDING TYPE-1999 EDITION

Building type

Assembly

.......................................................................... Education

......................................................................... Food

................................................................................. Lodging

............................................................................ Office

................................................................................ Retail

................................................................................ Warehouse

....................................................................... National

............................................................................ Building type floor
area weight

0.068 0.218 0.027 0.079 0.190 0.246 0.173 Electric

55.71 31.59 102.78 41.04 44.56 48.14 17.91 40.04 Whole building energy use intensity (kBtu/sf-yr or $/sf-yr)

Gas Site EUI Source EUI

33.88 89.59 215.04 20.05 51.64 122.88 34.91 137.69 366.12 15.94 56.98 148.41 6.32 50.88 148.95 5.17 53.31 159.08 9.11 27.02 67.15 12.91 52.95 141.88 46471

$UI

1.48 0.87 2.32 1.00 1.09 1.23 0.27 0.99

$UI

1.37 0.79 2.35 0.95 0.98 1.05 0.43 0.92

Table 3 presents the estimated percent energy savings betweenthe 1989 and 1999 editions. Overall, considering those differences that can be reasonably quantified, the 1999 edition will increase the energy efficiency of commercialbuildings. However, this is
nottrue for newbuildings ofall building types. In the case ofthe Food Service and the Warehouse building categories, the 1999 edition will allow increased energy usage. This is primarily due to an increased lighting power allowance for these building categories under the 1999 edition. Numbers in Table 3represent percent energy savings. Thus, negative numbers represent increased energy use.

TABLE 3.-ESTIMATED PERCENT ENERGY SAVINGS WITH 1999 EDITION-BY BUILDING TYPE

Building type

Assembly

.......................................................................... Education

......................................................................... Food

................................................................................. Lodging

............................................................................ Office

................................................................................ Retail

................................................................................ Warehouse

....................................................................... National

............................................................................ Building type floor

area weight

0.068 0.218 0.027 0.079 0.190 0.246 0.173 1.000 Percent reduction in whole building energy use intensity

Electric Gas Site EUI Source EUI

9.5 5.3 4.4 7.2 11.4 -6.3 5.2 8.6 -1.2 1.7 -0.4 -0.8

4.1 9.5 5.7 4.8 10.6 12.7 8.2 9.7 15.7 -30.7 12.7 14.7 71.6 -11.3 -45.1 -58.7

7.6 -6.8 4.5 6.4 $UI

7.5 9.0 -0.9

4.7 9.8 14.9 -59.7 6.6

A comparison ofenergy savings by buildingtype for each ofthe different standard scenarios modeled is shown in Table 4, to give an idea ofwhere most ofthe savings or increases derive. For example, we estimate a slight percentage increase in energy use intensity indicated in the "1989 edition with 1999 edition envelope requirements" row, indicatedby the negative savings. Similarly there is an estimated percentage increase in gas energy use intensity indicated in the "Gas EUI" column, also indicatedby negative savings. Conversely, otherrows indicate estimated percentage reduction in energy use intensity for lighting and mechanical requirements.

TABLE 4.-PERCENT ENERGY SAVINGS FROM 1989 EDITION [National figures, all building types]

Standard scenario Electric EUI Gas EUI Site EUI

1989 edition

............................................................................................. 0 0 0 1989 edition with 1999 edition envelope requirements

........................... 0.1 -4.3 -0.9 1989 edition with 1999 edition lighting requirements

.............................. 5.9 -8.3 2.8 1989 edition with 1999 edition lighting and envelope requirements

....... 6.0 10.1 2.5 Source EUI 

# I $UI 

# ol 0

-0.31 -0.3

4.6 4.9 4.6 4.846472 

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices

TABLE 4.-PERCENT ENERGY SAVINGS FROM 1989 EDITION-Continued [National figures, all building types]

Standard scenario Electric EUI Gas EUI Site EUI Source EUI $UI

1989 edition with 1999 edition mechanical requirements
······················· 2.2 1999 edition compliant buildings

............................................................. 7.6

III. Discussion ofDetailed Textual Analysis

The 1999 edition is written in code language and as a result excludes some ofthe guidance provided inthe 1989 edition. Although the guidance inthe 1989 edition is not enforceable, it provided designers with suggestions for implementing energy efficient solutions. However, the guidance in the 1989 edition made it difficult for designers and code officials to quickly identify the relevant criteria.

A. Lighting andPower

1. Interior Lighting Power Exemptions

The 1989 edition entirely exempts a number oflighting categories such as display or accent lighting for galleries, and lighting in spaces designed for the visually impaired. In doing so, it also exempts controls for those lights. While the 1999 edition exempts the lighting power requirements, itretains requirements for controls in the exempted areas. Lighting for outdoor manufacturing, commercial greenhouses, and process facilities; and special lighting for research are exempt inthe 1989 edition butnot in the 1999 edition. These differences canbe expectedto result in some reduction in lighting poweruse as a result ofthe additional coverage inthe 1999 edition. Conversely, there are a number of narrowly targeted exemptions in the 1999 editionthat are not in the 1989 edition. These include: lighting integral
to equipment installedby its manufacturer; lighting integral to open and glass enclosedrefrigerator and freezer cases; lighting integral to food warming and preparation equipment; lighting in interior spaces that have been designated as a registered interior historic landmark; exit signs; lighting that is for sale or lighting educational demonstration systems; and casino gaming areas. The first three ofthese are not generally controlledby the 1989 editionbecause they are rarely known at the time the lighting plans are approved. While portions ofgaming areas are often considered entertainment areas and exempt, the broader 1999 edition exemptioncanbe expectedto increase energy use in casinos. Lighting for landmarkinteriors might also increase in some cases. The net effect ofthese differences in exempted spaces is expected to be a small increase in efficiency inthe 1999 edition.

2. Exterior Lighting Power

The 1989 editionprescribes maximum installed lighting power (Watts/square foot or Watts/ linear foot) for exteriorbuilding and grounds areas that, when added together, become the allowed exterior wattage. The 1999 edition sets similar criteria for exits,
entrances and surface areas or facades, but also adds an efficacy requirement of 60 lumens per Watt in luminaries of

more than 100 Watts. There is a three Watts per lineal foot increase in allowable wattage for entrances without canopies in the 1999 edition. However, there is a decrease in allowable wattage for all exits (five Watts per lineal foot), and for high traffic canopied entrances (seven Watts per square foot), and for light traffic canopied entrances (one Watt per square foot). The netimpact is unknown as data on the number of building entrances and exits and their characteristics are not known.

For loading areas, loading doors, storage and non-manufacturing work
areas, and driveways, walkways, and parking lots, the 1999 edition deviates from the 1989 edition by eliminating any Watts/square foot or Watts/linear foot maximums and instead sets an efficacy requirement of60 lumens per Watt (more than 100 Watts per luminaire). This requirement in the 1999 edition eliminates the use oflow efficiency technologies, such as incandescent lamps, and allows the economics of fixture and energy cost to restrict the exterior lighting use to the minimum needed. We are aware ofno data on which to make ajudgement as to net decrease or increase in energy use from this change.

3. Lighting Controls-Interior

The 1989 editionrequires control points for each task or group oftasks within a 450 square foot area. It "counts" control "points" (one for manual, two for occupancy sensors, etc.)
to show compliance withthis requirement, giving credit to automatic controls versus manual ones. It further
sets a minimum ofone control for each 1,500 Watts oflighting. In place ofthis task control requirement, the 1999 3.0 2.4 2.3 2.2 6.8 4.5 6.4 6.6

editionrequires all buildings more than 5,000 square feet in size to have automatic lighting shutoffin all spaces usingtime ofday, occupancy sensor or similar methods. Buildings more than 5,000 square feet make up approximately halfthe number of commercial buildings built and more than 89 percent ofthe floor area constructed. This should save energy in thesebuildings during unoccupied hours. Where occupant sensors are used
to comply with the requirement, the savings shouldbe greatest, sincethis will shut offlights in unoccupied individual spaces, even during regular business hours.

The 1999 edition adds control requirements for six specific lighting functions: all task lighting, hotel/motel guestrooms, display/accent lighting,

case lighting, nonvisual (plant growth, food warming), and demonstration (for sale or for lighting demonstration). Furthermore, the 1999 editionrequires that spaces up to 10,000 square feet in size have at least one control per 2,500 square feet and that larger spaces have

one control per 10,000 square feet. In buildings with large open areas with multiple task areas lit by general lighting, the 1989 edition wouldrequire

more (total manual or automatic) switching than the 1999 edition. The 1999 edition instead reduces lighting

use in unoccupied spaces with automatic controls that do not require human intervention. The 1999 automatic control requirements are

more likely to reduce lighting energy

use in these spaces, thanthe manual controls permitted inthe 1989 edition.

The 1989 edition provides lighting control credits for use in calculating interior lighting power densities to encourage theuse ofautomatic controls. For each area or group oflights that are controlled by an occupancy sensor, lumen maintenance sensor, daylight
sensor, or combination ofsensors, the design connected lighting power value, used in showing compliance, canbe reduced from 10 percent to 40 percent, depending on the controls used. This allows more lighting power to be used in the space in exchange for the use of

an automatic lighting control. The 1999 editionrequires the use ofautomatic

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices 46473

controls without allowing an increase in connected power.

The 1989 editionrequires permanently wired lighting fixtures and switchedreceptacles inhotel suites of

rooms to be controlled at the entrance to each room. The 1999 edition further requires this control to be at the
entrance ofthe entire suite area. The 1999 edition should save energy by making it easier to turn offall the lights

on the way out.
4. Ballast Efficacy Factor

The 1989 edition includes a minimum ballast efficacy factor. The 1999 edition does not. However, newballast manufacturing standards, required under theEnergy Policy and Conservation Act, serve the same purpose and no longer make it necessary to include such criteria inthe 1999 edition. There will be no change in energy use as a result ofthis difference.

5. Exit Signs

The 1999 edition includes an additional section specifying a minimumefficiency (35 lumens per Watt) for all exit signs operating at greater than 20 Watts that is intendedto eliminatethe use ofstandard incandescent lamps in exit signs. This will essentially eliminate the use of incandescentexit signs thereby reducing energy consumption.

6. Interior Lighting Power-Whole Building

The 1999 edition provides greater clarity in specifying the calculation of luminaire or lighting system wattage that covers selfballasted, remote ballasted, track lighting systems and other miscellaneous lighting. This could eliminate some underestimation of installed lighting power. For example, it is common for a fluorescent lighting fixture to be described by builders (with respect to power consumption) as the simple sum ofthe lamp wattages while ignoring ballast energy use.

The 1989 edition presents a set of wholebuilding lighting power density requirements for 11 buildingtypes in six different building size ranges (0- 2,000; 2,001-10,000; 10,001-25,000; 25,001-50,000; 50,001-250,000; and greaterthan 250,001 square feet). The 1999 edition presents a single set of whole building lighting power density requirements for 31 building types withoutbuilding size variation. For four ofthe building types, where there is a reasonable matchbetween 1989 and 1999 editions, the 1999 allowance is higher by 0.06 to 0.64 Watts per square foot. Seven other matched building types show the 1989 edition having lighting power allowances 0.20 to 0.80 Watts per square foot higher than inthe 1999 edition. Considering all eleven matched building types, there is an average reduction of0.11 Watts per square foot with the 1999 edition. Within the two building types representing the largest percentage of building floor area in the commercial
sector (office andretail) thereductions withthe 1999 edition are 0.40 Watts per square foot for office and 0.60 Watts per square foot for retail buildings. Because there is an average reduction oflighting power densities from the 1989 editionto the 1999 edition in all matching building types, and also a reduction in the lighting power densities allowed in the two largestbuildingtypes (office andretail), the overall effect ofthe wholebuilding lighting power density requirements in the 1999 edition will be
to provide increased energy efficiency in most buildingtypes. However, it shouldbe noted thatthere is an increase inthe lighting power allowance for warehouse and storage type buildings which are significant interms oftotal commercial building area. We expect a netreduction inenergy use, with the whole building requirements. (See also the quantitative analysis oflighting requirements, Table 4.)

7. Interior Lighting Power-Space-BySpace

Both the 1989 and 1999 editions present individualbuilding space lighting power allowance values for use in applying a space-by-space compliance method where individual space lighting power is aggregated to arrive at abuilding total power allowance. The 1989 edition's tabulated space-by-space allowances are used in the compliance process only after they have been adjusted by an Area Factor (AF) ranging from 1.0 to 1.8. This factor is used to increase the allowed lighting power when the shape ofthe room (the size and height) necessitates the use of additional lighting powerto achieve certain levels ofilluminance. The area factor that canbe used to calculate some space type allowances is limited. For example, the allowance for sports playing areas, corridors, open offices, and mechanical rooms cannotbe modified by an area factor, while the allowance for enclosed offices canbe modified by an area factor ofup to 1.55. Spaces that are used for multiple functions, such as auditoriums, conference, banquet, and meeting
rooms, are allowed an additional lighting power adjustment factor of 1.5. By contrast, this adjustment for room dimensions is alreadybuilt into the 1999 edition's space lighting power values, so adjustments for space dimensions are notpermitted. The 1999 edition does allow some additional lighting power allowances to accommodate specific lightingneeds. These include additional power for decorative lighting (1.0 Watt per square foot), additional power for VDT terminal lighting (0.35 Watts per square foot), and additional power for retail display lighting. In the latter case, either 1.6 Watts per square foot ofspecific display

area is allowed for general merchandise highlighting, or 3.9 Watts per square foot ofspecific display area is allowed for valuable merchandise highlighting. This additional power is only allowed if the specified luminaries are installed and can only be used for the specific purpose noted.

Itis difficult to assess the actual impact from the use ofthe 1999 edition's space-by-space method versus the 1989 edition's. This is because the allowed power density for a building will depend greatly onthe space makeup ofthebuilding, the individual

room dimensions (affecting the area factor adjustment) and any additional allowances that may apply. However, the average ofall matching 1989 and 1999 edition power density space values shows a 0.36 Watts per square foot decrease in the 1999 edition's values from those in the 1989 edition. Identical

room geometry configurations (based on those used in the development ofthe 1999 edition's lighting power densities)

were taken into account inreaching this conclusion. Furthermore, it is important
to considerthe items inboth editions that can modify these lighting allowances. For example, the 1989 edition would allowthe use ofa 1.5 additional lighting power adjustment factor for multipurpose spaces, such as "Auditorium," "Conference/Meeting Room," and "Banquet/Multi-Purpose Space." Whereas the 1999 edition wouldbe even more energy efficient because there is no such area factor adjustment.

Determining the impact ofthe additional power allowances in the 1999 edition is difficult, since any comparison with values inthe 1989 edition uses either examplebuildings or lighting models. Using either example buildings or lighting models requires many assumptions regarding what is "typical " in each type ofspace and how each space is used. For example, in the 1989 edition, thebase lighting power density for a mass merchandise
store in a warehouse type setting is 3.3 Watts per square foot. With the application ofan appropriate area factor (1.05), the 1989 edition's adjusted

### 46474 Federal 

### Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices

power allowance is 3.46 Watts per square foot. The 1999 edition starts with

a base lighting power density for all retail establishments of2.1 Watts per square foot. The 1999 edition allows additional lighting power for certain lighting activities includingretail sales lighting. These come in the form ofan additional 1.6 Watts per square foot of lighted area for merchandise highlighting and 3.9 Watts per square foot ofspecific fine merchandise display. The application ofthese allowances will depend on the layout of theretail space andhow and at what height lighting is employed. This is similar to how the area factor inthe 1989 edition depends on the geometry ofthe individual space.

Office space lighting has a similar difference betweenthetwo editions. The 1999 edition offers an additional power allowance for visual display terminal lighting. Spaces with decorative lighting similarly are allowed
extra power only for the decorative lighting used. No such allowances are included in the 1989 edition's values.

To make some assessment ofthe possible impact ofthese additional allowances, we developed characteristics ofa space underthe 1999 edition whose total space lighting power allowance would match that ofthe 1989 edition. For this comparison, we determined what additional lighting
power allowances would needto be applied to the 1999 edition's base value
to match the 1989 edition's value. This comparison allows for a determination ofany stringency associated withthe

use ofthe low base numbers inthe 1999 standard. In some ofthese cases a range ofpower values represents the possible variation in calculatedvalues using the 1989 standard. The 1999 standard allows for only one base value. Table 5 presents comparisons for a variety of representative cases.

TABLE 5.-ADDITIONAL LIGHTING POWER ALLOWANCE IN THE 1999 EDITION NEEDED TO MATCH THE 1989 EDITION LIGHTING POWER ALLOWANCE

Space type [Additional lighting type] 1989 edition adjusted total

power 1999 edition base power Possible scenarios of use of additional power in 1999 to equal 1989 edition value

Hotel Lobby [Decorative]

................ 2.51 2.38 .................. 1.7 Permits 20 percent of the entire space to have decorative lighting. Cannot reach the1989 edition's value (Max 1999 value= 1.85). Office-enclosed [Visual Display

Terminal]. Office-open [Visual Display Terminal]. 2.51 1.5

1.3

.................... Cannot reach the 1989 edition's value (Max 1999 value= 1.65).

Jewelry Retail [Highlight Merchandise]. 5.88 to 7.40

...... 2.1 In most cases, one cannot reach the 1989 edition's value (Max 1999 value = 6.00). Need to have 97 percent of the entire space covered with spotlighted fine merchandise displays, to reach the 1989 edition's lower value. Fine Merchandise Retail [Highlight 3.36 to 4.23

...... 2.1

.................... Need to have between 32 and 55 percent of space dedicated to spotlighted fine merchandise displays-or, more than 78 percent of the space dedicated to spotlighted general displays, to reach the 1989 edition's value. Merchandise].

Mass Merchandise (big box) Retail 3.30

.................. 2.1 75 percent of space dedicated to spotlighted general displays-OR30 percent of space dedicated to spotlighted fine merchandise displays, to reach the 1989 edition's values. [Highlight Merchandise].

Department Store Retail [Highlight 3.1 Oto 4.10

...... 2.1

Merchandise]. Need to have between 26 and 51 percent of space dedicated to spotlighted fine merchandise displays, or over 62 percent of the space dedicated to spotlighted general displays, to reach the 1989 edition's values. Food and Misc. Retail [Highlight 2.80

.................. 2.1

.................... Need to have 43 percent of space dedicated to spotlighted general displays, to reach the 1989 edition's values. Merchandise]. Service Retail [Highlight Merchan- 2.84 to 3.57

...... 1.05 to 1.32

......

dise]. Need to have between 46 and 92 percent of the entire space dedicated to spotlighted general displays, to reach the 1989 edition's values. Mall Concourse [Highlight Mer- 1.40 to 1.85

...... 1.8

.................... The 1999 value is within or close to possible 1989 values.

chandise].

In the case ofthe hotel lobby it would be possible to use the decorative lighting power creditin 20 percent of the entire space withoutexceeding the requirements ofthe 1989 edition, which is quite reasonable. However, in the case ofthe mall concourse example, no additional lighting power allowance is required for the 1999 edition lighting power allowance to equal or exceed the 1989 edition value. By contrast, the enclosed and open office examples show that the 1989 edition lighting value cannotbe achieved, even withthe maximum allowance possible applied.

In the case ofJewelry stores, in most

cases one cannotreach the 1989 value. Where one can reach the 1989 value, it would require an unreasonable 97 percent ofthe entire sales area to be covered with fine merchandise displays, in orderto meetthe 1989 value. In the Mass Merchandising, Food and Miscellaneous Retail and Service Retail categories, the additional areas of highlighted merchandise required to match the 1989 values are excessive and generally unrealistic. In the remaining
two examples (fine Merchandise and Department Store) the 1989 edition lighting values can be achieved with additional lighting power scenarios that

are generally reasonable for some ofthe
spaces, but only where low room cavity ratio values occur. Overall, these results indicate that the 1999 edition lighting values are more stringent, with the additional lighting power allowances

more than compensatedfor by the reduction inbase lighting powerin the 1999 edition.

8. End Use Metering

The 1989 edition had requirements for the subdivision ofelectrical power feeders by use category, to facilitate enduse metering in buildings with more than 250 kVA connected load. In addition it had provisions to check
meter loads ofindividual tenants with

more than 100 kVA ofconnected load. The removal ofrequirements for

### Federal 

### Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices 46475

subdividing metering loads, inthe 1999 edition, will make checkmetering and commissioning ofthese systems more difficult. In doing so, it will likely result in some increase in energy consumption.

9. Transformers

The 1989 edition suggested that buildingtransformers be selectedto optimizethe combination ofno-load, part-load, and full-load losses, and had

a requirementthat an annual operating
cost calculationbe done and added to the electrical design documentation for buildings with total building transformers more than 300 kVA. The requirement has beenremoved from the 1999 edition. However, the 1989 edition did not provide for a comparison over multiple possible system designs, that might have produced more efficient options. Thus, theremoval ofthe requirement is unlikely to have a significant impact onbuilding efficiency.

10. Motors

The 1989 edition had motor efficiency requirements for motors operating more than 500 hours per year. However, the efficiency levels included are less efficient than Federal manufacturing standards enacted in 1992 and thus have no impact onbuildingefficiency. 

### B. BuildingEnvelope

1. Air Leakage

The 1989 edition provides a series of air-leakage standards or requirements that individual components must meet. The 1999 editionreplaces all these standards with a requirement to use the National FenestrationRating Council's, 

### ProcedureforDeterminingFenestration ProductAirLeakage, NFRC 400, as the
test procedure. Table 6 compares the air leakage requirements for envelope openings in the two editions. The number in the right-hand column indicates thatthe 1999 edition permits

more air leakage and is therefore less stringent.

TABLE 

### 6.- COMPARISON OF AIR LEAKAGE REQUIREMENTS IN THE 

### 1989 AND 

### 1999 EDITIONS.

Product 1989 edition 1999 edition 1989-1999 difference

Windows: Aluminum Framed, Operable

...................................................................... 0.37 cfm/lon ft

......... 0.4 cfmfft2

............... +0.03 Aluminum Framed, Jalousie

....................................................................... 1.5 cfm/f2

................ 0.4 cfm/ft2

............... 1.10 +0.25 +0.34 +0.03 +0.15 +0.25 +0.35 Aluminum Framed, Fixed

............................................................................ 0.15 cfmlft2

............. 0.4 cfm/ft2

............... Vinyl Framed

............................................................................................... 0.06 cfm/ft2

............. 0.4 cfmlft2

............... Wood Framed, Residential

......................................................................... 0.37 cfm/ft2

............. 0.4 cfm/ft2

............... Wood Framed, Light Commercial

............................................................... 0.25 cfmlft2

............. 0.4 cfm/ft2

............... Wood Framed, Heavy Commercial

............................................................. 0.15 cfm/ft2

............. 0.4 cfmlft2

............... Skylights

............................................................................................................. 0.05 cfm/ft2

............. 0.4 cfmlft2

............... Doors: Aluminum Sliding

........................................................................................ 0.37 cfmfft2

............. 0.4 cfm/ft2

............... +0.03 +0.03 +0.06 +0.15 +0.30 Vinyl Sliding

................................................................................................. 0.37 cfmfft2

............. 0.4 cfm/ft2

............... Wooden, Residential

................................................................................... 0.34 cfm/ft2

............. 0.4 cfm/ft2

............... Wooden, Light Commercial

......................................................................... 0.25 cfmfft2

............. 0.4 cfm/ft2

............... Wooden, Heavy Commercial

...................................................................... 0.10 cfm/ft2

............. 0.4 cfm/ft2

............... Commercial Entrance, glazed

..................................................................... 1.25 cfmlft2

............. 1.0 cfm/ft2

............... 0.25 -0.85 Commercial Entrance, opaque

................................................................... 1.25 cfm/f2

.............. 0.4 cfm/ft2

............... Residential Swinging

................................................................................... 0.50 cfmlft2

............. 0.4 cfm/ft2

............... -0.10 Aluminum Wall Sections

.................................................................................... 0.06 cfmfft2

............. Not covered

............. +

The impact ofthese changes on energy efficiency is hard to evaluate. Air leakage requirements for windows are less stringent for sixwindow types and

more stringent in one window type in the 1999 edition. Skylightrequirements

are more stringent inthe 1999 edition than inthe 1989 edition. Doors are more stringent for three types and less stringent for five othertypes, in the 1999 edition. Jalousie windows are not

a predominate window type in commercial construction,butthere has been a significant increase in allowed leakage rate for other window types under the 1999 edition. Therefore, the overall impact in comparingthe requirements for window air leakage is

a reduction in stringency.

For doors, there are significant increased leakage rates for wooden doors and slight increased leakage for sliding doors. However for the categories of "Commercial entrance doors" and for "All other commercial doors," there are expected to be significant reductions in allowed leakage. Because ofthe predominance of commercial steel doors inthe latter category, webelieve door air leakage requirements are more stringent inthe 1999 edition.

The 1999 edition does include additionalrequirements for loading dock weather seals in colder climates (greater than 3,600 heating degree days, base 65 degrees Fahrenheit) and also a requirement for vestibules in commercialbuildingentrance doors. Vestibules are notrequired in climates ofless than 1,800 heating degree days, base 65 degrees Fahrenheit; inbuildings ofless than four stories; where doors
open directly from a dwelling unit; where doors open directly from a space less than 3,000 square feet in area; in buildings entrances withrevolving doors; and where doors are used primarily to facilitate vehicular
movement or material handling and adjacent personnel doors. These requirements are not present inthe1989 edition. The combination ofthe more stringentrequirements for "commercial" doors and loading dock and vestibule requirements should improve energy efficiency inbuildings where they are required.

We would expect there to be fewer doors than windows in most commercial buildings. We therefore expect an overall decrease in stringency due to air leakage under the 1999 edition.

2. Insulation Installation

The 1999 edition requires that insulationbe installed in substantial
contact with the inside surface of cavities. Italso requires that lighting fixtures, heating, ventilating, and airconditioning, and other equipment not be recessed in such a manner as to affect the insulation performance. Finally, the 1999 editionbans installation of insulation on suspended ceilings with

### 46476 Federal 

### Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices

removable ceiling panels. The 1989 edition does not address this subject at all. These 1999 edition insulation installation requirements are expected
to save energy in commercialbuildings.

3. Allowance for SpeculativeBuildings

Buildings constructed on speculation thatthey willbe leased or occupiedby

as yet unknown occupants are referred
to as "speculative"buildings inthe 1999 edition. Speculativebuildings are often designed andthe envelope constructed prior to the final occupancy beingknown. Both the 1989 and 1999 editions cover this issue, albeit in somewhat different fashion. The 1989 edition sets the most stringent envelope requirements likelyto be encountered to be installed in thebuilding from the start, while the 1999 edition allows a less stringent envelope to be installed to accommodate a less demanding occupancy (such as a semi-heated warehouse), butthenrequires an upgrade to the envelope efficiency ifthe buildinguse changes to a more demanding occupancy (such as office space). We believe that under the 1999 edition the transition from a semiheated space (such as the conversion of

a warehouse heated for freeze protection only to a conditioned space for other

use such as office) would entail the addition ofheating capacity, and likely cooling capacity inmost climates. Similarly, changes in lighting would likely occur. Building inspections would normally be required which would trigger a review ofenergy code requirements. Whilethese approaches differ, we do notbelieve the difference will impact the overall energy use of commercial buildings.

4. Envelope ThermalTransmittance in Cold Climates

The 1989 edition has an explicit set ofrequirements for the building envelope (wall, roof, and fenestration) for cold climates with more than 15,000 heating degree days, base 65 degrees Fahrenheit. The 1999 edition addresses these cold climates inthreebins, or groupings ofranges ofdegree days, that

are slightly different from the 1989 edition. These threebins include criteria for buildings in climates with heating degree day, base 65 degrees Fahrenheitbetween 12,601 and 16,200 (bin 24), between 16,201 and 19,800 (bin 25) and more than 19,801 (bin 26). The envelope criteriavary with differences in construction (see Table 7). The U-factor requirements in the 1999 edition are generally less stringent. However, the only U.S. climate in the 1989 or 1999 edition's weather data that would fall underthe "cold climate" requirements wouldbeBarrow Alaska. Thus we expect any impactto be negligible because ofthe small amount ofconstruction in Barrow and similar smaller cold climate communities.

TABLE ?.-DIFFERENCES IN BUILDING ENVELOPE THERMAL REQUIREMENTS IN COLD CLIMATES BETWEEN THE 1989 AND
1999 EDITIONS

Envelope element 1989 edition cold climate (> 15,000 HDD65) re- quirements 1999 Edition bin 25 (16,201-19,800 HDD65) re- quirements

Opaque Wall

........................................ U-0.053 for large buildings

..................................... U-0.045 to 0.071, depending on type of wall. U-0.040 for small buildings Fenestration

......................................... U-0.52 (for window to wall ratios of less than 0.2 U-0.43, for the corresponding WWR values. for large buildings and 0.15 for small buildings). Roof

...................................................... Floor Over Unconditioned Space

......... Slab on Grade Insulation

..................... U-0.024

................................................................... U-0.023

................................................................... R-15 for 48 inches

.................................................. U-0.027 to 0.049, depending on type of roof. U-0.033 to 0.064, depending on type of floor. R-15, for 24 inches. Skylight

................................................. Not allowed

............................................................. U-0.95.

5. SkylightThermal Transmittance and Solar Heat Gain

Forbuildings whose overall roofUfactor, including skylights, is less than the 1989 edition's requirements, no separate skylight requirements must be
met. Forbuildings that cannotmeet this requirement, the 1989 edition contains skylight thermal transmittance requirements that are a function of heating degree days, base 65 degrees Fahrenheit, as well as provides credit toward the overall roofU-factor requirement, where lighting controls are used to reduce lighting consumption. The 1999 edition has separate requirements for glass skylights with curbs, plastic skylights with curbs, and skylights without curbs, which vary by climate bin. The least stringent ofthese

are for glass skylights with curbs. The 1999 edition provides no envelope credits for using lighting controls in conjunction with skylights. A comparison ofthe 1989 and 1999 editions' U-factor requirements is shown in Table 8. The original 1989 edition hadU-factors based on center of window measurements. The 1999 edition has U-factors based on whole window measurements. We used Ufactors based on whole window
measurements which are incorporated in Addenda F to the 1989 edition, for an accurate comparison.

TABLE 8.-COMPARISON OF SKYLIGHT U-FACTOR REQUIREMENTS IN THE 1989 AND 1999 EDITIONS

Climates with: 1989 edition 1999 edition

HDD65 <8000

............................................................................................................................................... U-0.7 U-1.17 to 1.98 (glass). U-0.88 to 1.17 (glass). Included in U-factor for HDD65 28000

............................................................................................................................................... U-0.52 Skylight curbs all climates

............................................................................................................................ U-0.21

Furthermore, the 1989 editionlimits the maximum allowable percent of skylight area, based on skylight visible light transmittance, number ofheating degree days, base 65 degrees Fahrenheit, number ofcooling degree hours, base 80 degrees Fahrenheit, foot candle level, and interior lighting power density. The allowable percent ofroofarea in skylight ranges from about 2 percent to skylights with curbs.

12 percent for specific combinations. The 1999 edition limits skylights to 5 percent ofroofarea.

The 1989 edition is more stringent than the 1999 edition in terms of

### Federal 

### Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices 46477

required skylight U-factor. Onthe other hand, the total area ofskylight that can be installed is less in the 1999 edition. In other words, the 1999 edition has greater restriction on tbe total roofarea in skylights, but does allow skylights with a higher U-factor to be used. This essentially allows the user ofthe 1999 editionto put in a smaller amount of less efficient skylight than the 1989 edition.

The 1989 edition does not have any requirements for skylight solar heat gain. The 1999 edition does include specific solar heat gain coefficient requirements for skylights. Solar heat gain coefficient values for glass skylights range from 0.16 in very warm climates to "NoRequirement" in very cold climates. Implicit inthe1989 edition's thermal transmittance requirements, however, are SHGC values associated with the required glass. With required U-factors at 0.7 and 0.52 for skylights, skylights wouldhave
to be constructedwith glazing similarto double pane and double low-emissivity glazing. Such construction would have solar heat gain coefficientvalues of0.68 and 0.59. Using this logic, a comparison ofskylight solar heat gain coefficient values is constructed in Table 9. Values

are taken for five percent ofthe roofarea in skylights, as this is the maximum prescriptive level inthe 1999 edition. The upperrange ofsolar heat gain coefficient values in the 1999 edition column is for cooler climates within eachrange.

TABLE 9.-COMPARISON OF SOLAR HEAT GAIN COEFFICIENTS IN THE 1989 AND 1999 EDITIONS

Climates with: 1989 edition SHGC 1999 edition SHGC

HDD65 9,500

........................................................................................................................................................ 0.68 0.16 to 0.62. 0.36 to 0.64. HDD65 ?.7,500 <10,801

.......................................................................................................................................... 0.59 HDD65 >10,801

...................................................................................................................................................... 0.59 No requirement.

The 1999 edition solar heat gain coefficient requirement is more stringent for virtually all locations inthe US. The 1989 edition does have lower solar heat gain coefficientrequirements in very cold climates,but since solar gain is a netbenefit inthese climates, restricting solar gain provides no benefit.

The lack ofdata onthe amount of skylight in various parts ofthe country makes it inappropriate for us to reach a conclusion as to the net impacts ofthese changes.

6. Slab-On-Grade and Below Grade Wall Insulation

Slab-on-grade insulationrequirements

are nonexistent inboth editions in

warm climates. For cooler climates, the 1989 edition requires betweenR-7 and R-8 for vertical insulation, extended 24 inches deep, whereas there are effectively no requirements for slab insulation in the 1999 edition in the continental U.S. For heated slabs, the 1989 editionrequires an additional insulation level ofR-2, to that required for unheated slabs, in all cases. For below grade walls, the 1989 edition requires insulation levels from R-7 to R-16, for the first storybelow grade, depending on location. Whereas there

are effectively no requirements for below grade wall insulation inthe 1999 edition, until above 9,000 heating degree days, base 65 degrees Fahrenheit (much ofAlaska and some northern Minnesota locations). Thereduction of slab-on-grade and below grade wall insulationrequirements in the 1999 edition will result in higher heating loads incold climates, particularly for small buildings, resulting in more energy use. While a reduction in stringency, the impact oftheremoval of below grade or slab wall insulation is temperedby the insulating effect ofthe surrounding earth, relative to removing insulation from envelope components exposed to the air and sun (such as walls androofs).

7. RoofThermal Transmittance

We looked at roofthermal transmittance requirements first by estimatingthebuilding footprint area (assumed to approximate theroofarea) by dividing the floor areaby the number offloors for eachbuildingtype. We then applied the Commercial Building Energy Consumption Survey statistical weights to each buildingtype, to develop a table ofthe estimatedroof

area. This was done for each roof surface type classification for each of the 18 building use classifications inthe 1992 Commercial BuildingEnergy Consumption Survey. There are 17 Commercial BuildingEnergy Consumption Survey roof surface classifications, which were aggregated into the three rooftypes inthe 1999 standard as shown in Table 10, below. Where a significant fraction ofa particularroof surface classification could be divided into one or more construction categories, estimates were made ofthe relative percentage in each category and are shown in parentheses in Table 10. Finally, the fraction of estimated roofarea for each roof construction is shown for nonresidential, semi-heated, and residential
space types.

TABLE 10.-ESTIMATED ROOF AREA FRACTIONS BY 1999 EDITION ROOF CONSTRUCTION CATEGORY

Estimated roof area fraction 1999 edition room con- struction CBECS 1992 roof surface classifications (in percent)

Non-residential Semi-heated a Residential b

Insulation Entirely Above Built-up, Built-up & metal, Built-up & s/m ply, Com- 50.2 45.9 45.6

Deck. posite, Foam/Styrofoam, Single/multiple ply (33%), Shingles &built-up (50%). Metal Building

................... Metal/Rubber (80%), Metal Surfacing (80%), Single/ 16.5 32.9 4.9 multiple ply (33%).

### 46478 

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices

TABLE 10.-ESTIMATED ROOF AREA FRACTIONS BY 

### 1999 EDITION ROOF CONSTRUCTION CATEGORY-Continued

Estimated roof area fraction 1999 edition room con- CBECS 1992 roof surface classifications (in percent) struction Non-residential Semi-heated a Residential b

Attic and Other

................. Concrete Roof, Metal/Rubber (20&), Metal Surfacing (20%), Other (specify), Shingles & metal, Shingles & s/m ply, Shingles (not wood), Single/multiple ply (33%), Shingles & built-up (50%), Slate & shingles, Slate or tile, Wooden materials.

a Non-refrigerated warehouse assumed.

b Lodging buildings only.

Metal surfacing (about 13% offloor area) canbe considered part ofa metal buildingroofor a roofwithmetaljoists (big boxbuildings such as Walmarts). The 80/20 splithere allocates most of these surfaces to metal buildings which

are the more prevalent class ofnew commercial construction. The shingles/ slate, tile/wooden materials, are likely to be in place on roofs with attics or single rafter roofs, because they rely on roofpitchto shed water. The remaining categories cover a variety of combinations ofmaterials, mainly synthetic/rubber surfaces. Some ofthese may be flat roofs, butthey couldbe metaljoists roofs or deckroofs. We allocated these evenly over the 1999 edition's roofconstruction categories.

The fractions ofrooftypes estimated

were used to weight the required Ufactors from the 1999 edition for each climate and for each category of building, non-residential, semi-heated, andresidential.

The results shown in Table 11 suggest that for most non-residential buildings, the 1999 edition has more stringentroof U-factor requirements in warm to mild climates (significantly so in Knoxville and Los Angeles, moderately so in Orlando, Seattle, and Shreveport, and slightly so in Fresno). Itis slightly less stringent in the cooler climates of Denver, Detroit, and Providence, and is significantly less stringent in Minneapolis and Phoenix. Overall, we expect a slight increase inheating energy use and slight decrease in cooling energy use for most nonresidential buildings from these requirements.

The semi-heatedbuilding category in the 1999 edition shows a substantial 33.3 21.2 49.4

increase in average U-factor for all buildings, which is expectedto result in increased energy use due to increased heating loads for these buildings.

A comparison ofthe requirements for the residential space category in the 1999 edition shows a reduction in Ufactor (increase in stringency) for all climates except Los Angeles, which shows a substantial increase in U-factor (decrease in stringency).

Overall, it is expected that the changes in U-factor requirements in the 1999 edition will result in some increase inheating energy use, primarily as a result ofthe significant changes inrequirements for semi-heated
spaces. Itis expected thatit will also result in some decrease in cooling
energy use in most (but not all climates).

TABLE 11.-AVERAGE ROOF U-FACTOR REQUIRED

City

Denver

.................................................................................. Detroit

................................................................................... Fresno

.................................................................................. Knoxville

............................................................................... Los Angeles

......................................................................... Minneapolis

.......................................................................... Orlando

................................................................................ Phoenix

................................................................................ Providence

........................................................................... Seattle

.................................................................................. Shreveport

............................................................................

1Negative U-factors indicate decreased stringency. 1989 edition

0.051 0.053 0.059 0.110 0.100 0.045 0.063 0.046 0.053 0.064 0.066 Non-res

0.054 0.054 0.054 0.054 0.070 0.051 0.054 0.054 0.054 0.054 0.054

8. Floors Over Unconditioned Spaces

For each climate, the 1989 edition provides a single prescriptive U-factor for floors, while the 1999 edition provides nine possible U-factors (or Rvalues) depending on buildingtype and floor type. Therange ofrequirements for the 1999 edition addresses wood framed, steel framed, and mass (concrete) floor construction separately. Typically, wood framed floors have the lowest (most stringent) U-factor requirement, whilemass floors have the highest (least stringent) U-factor. The 1999 edition Change 1989-
Semi-heated Residential 1999 Non-res1

0.123 0.045 -0.003 0.123 0.045 0.001 0.172 0.045 0.005 0.149 0.045 0.056 0.202 0.200 0.030 0.123 0.045 0.006 1.140 0.045 0.009 0.172 0.045 0.008 0.123 0.045 0.001 0.149 0.049 0.010 0.172 0.045 0.012

1999 edition is typically more stringent for wood framed and steel framed floors, and less stringent for mass floors in nonresidential (and residential) buildings. The 1999 edition is less stringent for semi-heated buildings. See Table 12.

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices 46479

TABLE 12.-COMPARISON OF FLOOR OVER UNCONDITIONED SPACE U-FACTOR CRITERIA IN THE 

### 1989 AND 

### 1999 EDITIONS

1999 edition 1989-1999 difference

1989 edition Non-residential Semi-heated Non-residential City all floors Wood Steel Wood Steel Wood Steel Mass frame & joists Mass frame & joists Mass frame & joists

other other other

Orlando

............... 0.28 No requirement No requirement 0.280

Phoenix

.............. 0.19 0.051

Los Angeles

....... 0.17

Shreveport

.......... 0.11

Fresno

................ 0.10

Knoxville

............. 0.074 0.051

Seattle

................ 0.056

Denver

................ 0.049 0.033

Detroit

................. 0.048

Providence

......... 0.048

Minneapolis

........ 0.040

9. OpaqueWall Thermal Transmittance

The 1989 edition provides a single prescriptive U-factor for lightweight walls and a range ofpossible U-factors for mass walls (depending on thermal
mass, percent fenestration, and internal load density), while the 1999 edition provides 12 possible U-factors (or Rvalues) depending onbuildingtype and wall construction. Themaximum thermal transmittance requirements for

mass walls inthe 1999 edition generally fall within the range ofallowable values inthe 1989 edition, except for semiheatedbuildings where in all cases the 1999 criteria are less stringent. However, sincebuildings inthe semiheated category are expected to have relatively low heating loads (due to the low internal temperature and limited 0.052 0.137 No requirement 0.139 0.138 0.053

0.052 0.107 0.660 0.069

0.052 0.087 0.066 0.069

heating capacity) and no cooling loads, the reduction in stringency is expected
to have a minimal impact.

The difference in criteria for lightweight walls betweenthe 1989 and 1999 editions varies, with some wall types being more stringent in some locations and other less stringent. In general, wood framed wall requirements inthe 1999 edition are most likely to be

more stringent than corresponding requirements in the 1989 edition.

To compare requirements for mass walls inthe1989 edition, we used the Alternate Component Packages tables to determine U-factor requirements for 8 inch solid concrete and solid grouted
concreteblock mass walls (Heat Capacity> 15 Btu/ft\2\-F) as well as for 8 inch unfilled or insulated concrete block walls (10 Btu/ft\2\-F <Heat 0.119 0.118 0.033

0.059 0.058 0.027

0.049 0.048 0.037

0.322 0.023 0.022 -0.033

0.050 0.004 0.051

0.322 0.016 0.003 -0.038

0.015 0.004 0.039

0.015 0.004 -0.039

0.007 -0.012 0.047

Capacity< 15 Btu/ft\2\-F). We did this for insulation on the inside ofthe wall; integral withthe wall; and onthe outside ofthe wall, under each ofthe three internal load density (ILD) ranges inthe Alternate ComponentPackages tables. This was done for the 11 locations and for 18 percent and 38 percent window to wall area ratios. The requirements used were based on interpolation across the tabulated fenestration levels. For each internal load density range, we averaged together all calculated U-factor requirements. These results are shown in Table 13. In addition, we showthe 1999 edition's Ufactor requirements by that edition's three space-type categories (nonresidential, residential, and semiheated).

TABLE 13.-MASS WALL REQUIREMENTS COMPARISON

1989 edition mass wall requirements 1999 edition mass wall requirements U-Factor difference

Location Interior load density Non-resi- Semi-heat- Non-resi- Non-residential Residential ed dential dentiala Residential b Low Medium High

ORL

.......... 0.624 0.649 0.636 0.58 0.151 0.58 -0.062 -0.473 -0.044 PHX

.......... 0.404 0.403 0.400 0.58 0.151 0.58 0.179 -0.253 0.176 LOS

.......... 0.737 0.791 0.793 0.58 0.151 0.58 0.212 -0.586 -0.157 SHR

.......... 0.301 0.327 0.328 0.58 0.123 0.58 0.252 -0.178 0.279 FRS

.......... 0.293 0.307 0.311 0.58 0.151 0.58 0.271 -0.142 0.287 KNX

.......... 0.166 0.185 0.188 0.151 0.104 0.58 -0.036 -0.062 0.414 SEA

.......... 0.123 0.140 0.147 0.151 0.104 0.58 0.007 -0.019 0.458 DET

.......... 0.100 0.107 0.109 0.123 0.09 0.58 0.015 0.010 0.480 DEN

.......... 0.131 0.144 0.144 0.123 0.09 0.58 -0.021 0.041 0.449 PRV

.......... 0.100 0.107 0.109 0.123 0.09 0.58 0.015 -0.010 0.480 MNP

......... 0.078 0.087 0.088 0.104 0.09 0.58 0.017 0.012 0.502

aNon-Residential versus average of Medium and High Interior Load Density cases.

### 46480 

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices

b Residential versus Low Interior Load Density case.

c Semi-heated versus Low Interior Load Density case.

The difference in required U-factors for typical buildings is also shown in Table 13. For this comparison, we have assumedthat most non-residential buildings in the 1999 edition would fall into eitherthe medium or high interior load density ranges ofthe 1989 edition. The average U-factor for both ofthese interior load density ranges was used in the comparison. Most residential buildings would fall into the low interior load density range ofthe 1989 edition. Most semi-heatedbuilding spaces (assumed to be similar to warehousebuildings) would likely fall under the low interior load density range ofthe 1989 edition. As can be

seen from the table, therequirements of the 1999 edition are more stringent for residentialbuildings, in almost all climates. This is particularly so in moderate to warm climates. The 1999 editionis considerably less stringent for semi-heated buildings in all but Orlando and Los Angeles, where heating losses

are not expectedto be significant. The 1999 edition is generally less stringent for non-residential construction in moderate to warm climates and slightly less stringent for cool or cold climates. Overall, it is expectedthat the reduced U-factor requirements for mass walls in the non-residential and semi-heated category will result inincreased heating energy use over the 90.1-1989 mass wall requirements.

10. Window Thermal Transmittance and Solar Heat Gain

The 1989 edition does not specifically provide a prescriptive approachto windowthermal transmittance or solar heat gain, but rather treats windows as

a component ofthe building wall, where the wall must have certain overall heating and cooling performance to show compliance. However, the ACP (Alternate Component Packages) tables, which set out prescriptive requirements for thebuilding envelope, provide tables ofmaximum percentage ofwall glazing

as a function ofwindow U-factor, shading coefficient, projection factor, and building internal gains. The 1999 edition,by contrast, provides prescriptive U-factor requirements and Solar Heat Gain Coefficient requirements for particular combinations ofpercentage ofglazing andbuilding category (non-residential, residential, semi-heated), simplifying

use and enforcement. Both editions require the use ofan energy tradeoff methodology for buildings with very high percentages ofwindow area (typically greater than 50 percent).

For our analysis, we assumed the mid-internal gain range ofthe ACP tables (1.51-3.00 W/ft2) as being typical ofthe non-residential building loads, andthe low-internal gain range of the ACP tables (0.0-1.5 W/ft2) as beingtypical ofsemi-heatedbuildings such as warehouses. For residential space types such as hotels and hospitals, we assumed either low-or mid-internal gain ranges ofthe ACP tables couldbe appropriate in the 1989 edition. For multi-family high rise buildings we assumed low-internal gain ranges.

For these typical levels ofinternal gains, therequirements for window thermal transmittance inresidential and non-residential buildings are very similar in both editions. The 1989 edition is somewhat more stringent in cold climates inbuildings with a high percentage ofglazing. The 1999 edition is marginally more stringent inthe rest ofthe country. For semi-heated buildings, therequirements in the 1999 edition are less stringent, except for in

warm climates where both editions require single pane glass.

Window solar heat gain requirements inthe 1999 edition are typically more stringent in buildings with lower glazing areas (less than 30 percent), but often less stringent inbuildings with higher glazing areas (38 percent or 45 percent). Maximum solar heat gain requirements do not exist for semiheated buildings in the 1999 edition. However, limiting solar heat gain does
notreduce energy use for abuildingthat is only heated.

For windows with northern orientations, the 1999 edition generally allows greater solar heatgain per window area than the 1989 edition. A review ofsix ofthe seven buildingtypes (not including warehousebuildings which are commonly semiheated buildings) in the quantitative analysis suggested that approximately 73% of the floor area ofthese buildings would be inbuildings with glazing fractions of less than 30%. This suggests that overall, the 1999 editionis more energy efficient inreducing solar heatgain in
most buildings. Itis somewhat less efficient with regard to windowthermal transmittance, particularly in cold climates.

11. OpaqueDoors

The 1999 edition contains explicit Ufactor requirements for both swinging and non-swinging doors, with requirements ranging from a U-factor of 0.5 (for both door types in cold climates)
to 1.45 for uninsulated doors ofboth types. An insulated metal door or a solid wood door requires a U-factor of 0.5. Glass doors that are more than onehalfglass are considered to be equivalentto vertical fenestration and would needto meet vertical glazing requirements. The 1989 edition does not explicitly deal with either opaque or glazed doors, but instead treats them as part ofthe overall wall requirement. Opaque doors are part ofthe opaque wall, glass doors are part ofthe glazed

area. Sincethe required thermal performance ofopaque doors in the 1999 edition is generally worse than that ofthe surrounding opaque wall
area, and the opaque door requirements

are included in the overall wall requirements ofthe 1989 edition, the requirements ofthe 1999 edition are less stringent. Doors represent a small percentage ofthe wall area ofmultistory buildings. They also represent a fairly small percentage ofthe wall area of many large single story buildings. Most commercial entrance doors are glazed, reducing the impact ofthe difference in opaque door requirements. We therefore concludethatthe energy impact ofthis change is likely to be small for most buildings. However, in individual buildings with a significant number of doors, such as some warehouses, the impact may be significant.

C. Mechanical Equipment and Systems

1. Load Calculations and Sizing

The 1999 edition has no explicit sizing requirements for heating ventilation and air-conditioning systems. The1989 edition requires the

use ofa computational procedure for load calculations, and it details selection ofindoor and outdoor design temperature, the use ofStandard 62-89 for minimum ventilation, and a selection ofallowed sources for internal gain data. The 1989 edition also explicitly allows a ten percent safety factor for steady-state design loads and additional 30 percent and ten percent multipliers beyond that to account for heating and cooling pick-up loads. However, these additional parameters represent typical values or sources for sizing calculation data. The omission of explicit sizing requirements for heating ventilation and air-conditioning systems, while unlikely to have much impact on large commercial buildings, which are typically designedby

### Federal Register/Vol. 67, No. 135/Monday, 

### July 15, 2002/Notices 46481

engineering professionals, could have a significant impact on smaller commercial buildings, especially design-build facilities. The inclusion of explicit maximum safety factors inthe
1989 standard recognizes the tendency for much larger values to be used by system designers. The exclusion ofsuch factors in the 1999 standard has the potential for significantly oversizing equipment, resulting in operating inefficiency.

2. Separate Air Distribution Systems

The 1989 edition requires that zones with special process, temperature, and/

or humidityrequirements, eitherbe served by air distribution systems separate from those used to satisfy zones conditioned for comfort only, or have provisions to allow control for comfort conditioning only. An exception to this allows up to 25 percent ofthe air flow serving primarily process systems to be directed for comfort cooling only needs with no system design modification. This exception mightbe used for office space in an industrial facility. This requirement provides the ability to operate the primaryheating ventilation and air-conditioning systems for comfort conditioning only when processes are not operating. The 1999 edition has no requirements explicitly for systems and equipment used for process applications. However, where systems would also serve spaces conditioned for comfort only, the equipment and system requirements of the 1999edition would apply. In particular, requirements referring to

zone isolation, dehumidification, and simultaneous heating and cooling would address most ofthe issues addressedby the separate air distribution system requirement in the
1989 edition. This will result in a minor reduction in stringency in a limited number ofbuildings.

3. Temperature Controls

The 1999 edition has an additional requirement that all zone and loop controllers shall incorporate control

error correction. In addition, it explicitlyrequires a set point overlap restriction whenthe heating and cooling
to a zone are controlledby separate thermostats within that zone. In the
1989 edition, it is not clear whether individual thermostats are required that control both heating and cooling to a 5 degree Fahrenheitdeadband, or whether it means thatthe space should be controlled to provide a 5 degree Fahrenheit deadband. The additional requirements make the 1999 edition clearer as to the requirements and better
at controllingroom temperature and will limitreheating andrecooling done by separate systems, which will provide improved efficiency over the 1989 edition.

4. Off-Hour Controls and Setback

The 1999editionrequirements for offhour controls are limited to systems with heating or cooling capacity greater than 65,000 Btu per hour and fan system power greater than:% horsepower. The requirement for off-hour controls inthe
1989edition are for systems greater than
two kilowatts. Exceptions are also made for heatingventilation and airconditioning systems serving hotel or motel guestrooms. In these cases the
1999edition is less stringent. However, the optimum start controls required in the 1999edition for large systems, should reduce the number ofhours needed to bring the building to operating temperature.

The 1989 edition allows either independent shut-offcontrols or setback controls to reduce heating and cooling
to the zone. The 1999editionrequires automatic shutoffcontrols for the supply ofconditioned air, outside air, and exhaust air to each independent isolation area, as well as automatic shutdown controls. However, it specifically allows substitution ofa system air flow reduction inthe nonoccupied zones, but limits thetotal volume ofairto those zones to 14 percent ofthe system airflow. The 1999 edition, by requiring maximum setback air volumes, has explicit, and therefore

more stringent, off-hour requirements. These would be achieved by simple thermostat setback. Both editions incorporate different exceptions to these off-hour requirements for multi-zone systems. Our limited data on commercial building multi-zone systems and operating schedules is insufficient to evaluate these exceptions.

5. Dampers

The 1999editionrequires motorized dampers in stair and elevator shafts and in all outdoor air supply exhaust hoods, vents, and ventilators. Gravity dampers

are acceptable onbuildings less than three stories and ofany height in buildings in climates with less than 2,700 heating degree days, base 65 degrees Fahrenheit. These damper performance requirements are more stringent than similarrequirements in the 1989 edition. However, the requirements in the 1999edition pertain
to fewer systems (only to systems larger than 65,000 Btu per hour). The 1989 edition requires dampers (motorized or gravity) or other means ofvolume shutoffor reduction. Itexempts supply and exhaust systems less than or equal to 3,000 cubic feet per minute, in warm climates (less than or equal to 3,000 heating degree days. base 65 degrees Fahrenheit). Overall, the 1999 edition is considerably more stringent for large systems, but is less stringent for small systems in climates above 3,000 heating degree days, base 65 degrees Fahrenheit.

6. Humidity Control

The 1989 edition had a requirement that any humidity control device (humidistat) be capable oflimitingthe

use offossil fuel or electric energy to provide relative humidities ofgreater than 30 percent or less than 60 percent. This range limit setpointrequirement for zone humidification is not included in the 1999 edition. Instead a requirement for havingthe capability to prevent simultaneous humidification or dehumidification was added, with an exception for zones with tight humidity requirements, approved by local authorities, or for desiccant systems used in series with evaporative cooling. Minimum impact is expected from this change as both editions effectively require systems withboth humidification and dehumidification to have the controls to limit possible waste ofenergy thatwouldresult from simultaneous humidification and dehumidification.

7. Radiant Heating

The title, purpose, and scope ofthe
1989 edition do notinclude unenclosed spaces, and has no requirements for heating such spaces. Hence, warm air heating systems may be used. By specifically including such spaces as loading docks without air curtains in the 1999 edition's title, purpose, and scope, andrequiring radiant heating systems (excluding warm air systems).
energy will be saved by requiring more efficient systems for that application.

8. Ventilation

The 1989 edition requires ventilation systems be designed capable of providing the ventilation levels prescribed in Standard 62-1989. The
1989 edition did not set the ventilation rate, but rather specified a minimum operational ventilation rate the system mustbe designed to provide. Operation ofa system at higher or lower ventilationrates is allowed underthe
1989 edition. The 1999 edition omits these requirements. No savings or loss in efficiency should occur from this specific change.

Further, the newrequirements in the
1999 edition for automatic ventilation controls for high occupancy areas make the 1999 edition more stringent than the

### 46482 

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices

1989 edition and should provide some energy savings.

9. Pipe andDuct Insulation

The 1999 edition has slightly less stringent pipe insulationrequirements thanthe 1989 edition for most building applications. The 1999 edition does not require insulation ofpiping unions in heating systems or hotwater piping between the shutoffvalve and coil (up
to 4 feet ofpipe), in conditioned spaces. Itrequires more insulation onhigher temperature (> 250 F) piping, and less insulation on lower temperature heating system and service hotwater piping. In contrast, the 1989 edition requires more insulation on low temperature cooling system piping. Overall, there appears to be some smallreduction in insulation requirements. However, since the piping is insulated underboth standards,the incremental reduction in insulation is expectedto have minimal impact.

The 1999 edition has significantly less stringent duct insulationrequirements for some categories ofducts than the 1989 edition. For cooling only ducts, the 1999 edition requires generally lower insulation levels for ducts located outsidethebuilding, and insulation levels at or lower than required inthe 1989 edition for most spaces insidethe building. The 1999 edition, generally requires higher insulation levels for ventilated attics and for unvented attics with non-insulated attic decks, which

canbehigh temperature areas ofthe building. Itrequires no insulation for indirectly conditioned spaces including
return air plenums.

For heating only ducts, the 1999 editionrequires somewhatless insulation on exterior heating ducts, exceptinthe most extreme heating climates, where it requires more than the 1989 edition. It requires very little insulation on heating-only ductwork located insidethe building envelope.

For return ducts located exterior to thebuilding, the 1999 editionrequires lower insulation levels thanthe 1989 edition. The lower duct insulation requirements are likely to be most significant for heating-only ducts in climates where insulation is not required for particular attics or unconditioned spaces. The reduction in the minimum insulation level for cooling only ductwork is significant for central systems thatrely onyear round cooling availability (such as variable air volume or dual duct systems). Both insulation reductions will decrease energy efficiency ofthe 1999 edition.

Finally, the 1999 edition does not restrict the use ofpressure sensitive tape at seal level C for supply pressures up to 2inches ofpressure, whereas the 1989 editionrestricts its use for seal class C above 1 inch. Research is ongoing regarding the impact ofthis, however, we believe thatthere is a potential reduction in energy efficiency with the 1999 edition.

10. Heat Recovery

New requirements in the 1999 edition for exhaust air heat recovery for systems of5,000 cubic feet per minute or greater with 70 percent or greater outside air, will have significant positive impact on energy efficiency in heating ventilation and air-conditioning systems with high outside air requirements. However, the number ofbuildings that have these systems and that are exempted is significant.

Requirements have also been added that condenser heat recovery be used to provide heating ofservice hot water for buildings with a combination of continuous operation, high water heating loads (greater than 1,000,000 Btu per hour) and high cooling loads (approximately 400 tons). Primary examples are large hotel facilities. These requirements significantly increase efficiency, but in a relatively small percentage ofbuildings.

11. Completion Requirements

Both editions have requirements for testing and balancing ofheating ventilation and air-conditioning equipment. The 1999 editionrequires a written balancing report for zones more than 5,000 square feet in area, as well

as requires the ability to measure differential pressure across pumps greater than 10 horsepower in size. For buildings larger than 50,000 square feet conditioned area, detailed commissioning instructions for heating ventilation and air-conditioning systems

are requiredto be providedbythe designer in plans and specifications. An exception to this requirement is made for warehouses and semi heated spaces. The more detailed and extensive documentation requirements have the potential to provide long-term energy efficiency beyond what wouldbe expected under the minimum completionrequirements ofthe 1989 edition.

12. Simultaneous Heating and Cooling Controls

The 1989 and 1999 editions have essentially identical text requiring that

zone thermostatic and humidistatic controls shall be capable ofoperating the supply ofheating and cooling energy in sequence to prevent reheating, recooling, or mixing ofpreviously heated and cooled air, or other simultaneous operation ofheating and cooling systems in the same zone. Similarly, exceptions are provided for both editions regarding: (1) Zones with special pressurization or crosscontaminationrequirements; (2) zones where at least 75 percent ofthe reheat energy is provided from a site-recovered

or site-solar source; and (3) wherethe reheated volume ofsupply air to a zone is no greater thanthe maximum of several defined limits. However, the 1999 standard provides muchmore detailregarding the possible characterization ofthe circumstances under which these exceptions would apply. In the third category, the 1999 edition changes the stipulations to limit the use ofmost ofthese maximumreheated-air exceptions. These changes shouldresult in a reduction inbuilding energy use for many common multizone heating ventilation and airconditioning system designs.

13. Economizer Controls

The 1999 edition requires economizers in fewer locations than the 1989 edition, butrequires them inthe locations ofthe country where they are expected to be mostbeneficial. The 1989 editionrequires economizers on 7.5 ton or larger equipment in climates where economizers are required. The 1999 editionuses a sliding scale of economizer requirements. These requirements depend on climate and system size. They range from 65,000 Btu per hour equipment in climates where economizers are most effective to 135,000 Btu per hour where economizers are least effective. In addition, the 1999 editionrequires air economizers to be capable ofproviding 100 percent ofthe design supply air quantity, versus only 85 percent inthe 1989 edition. In addition, the 1999 edition specifies: (1) Allowed economizer control types to maximize economizer savings in specific climates, (2) leakage rates for outside air dampers, and (3) that economizer dampers in multi-zone systems be capable ofbeing sequenced with the mechanical cooling equipment and notbe controlled by only mixed air temperature. In general, the 1999 edition attempts to provide

more economizer savings where economizers are mostbeneficial.

14. Fan System Design Criteria

Both editions will result in similar fan power efficiencies. However, the 1999 edition requires the efficiencies be included on motor nameplates, in order
to make them more easily inspected. In addition, the 1999 edition places these requirements on fan motors offive horsepower and above, whereas the 1989 edition places requirements on

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002 /Notices 46483

motors that are ten horsepower and above. The 1999 edition also has more stringentunloading requirements for variable air volume fans. The 1999 edition places those requirements on variable air volume systems of30 horsepower and above, as compared to variable air volume systems of75 horsepower and above, as specified in the 1989 edition. Both the constant volume and variable volume fan power requirements will be extended to far

more system types inthe 1999 edition. Overall, there is expected to be a reduction in allowed fan poweruse in the 1999 edition, particularly for multi-

zone systems.
15. Pumping System Design

Both editions require that pumping systems designed for variable flow be designed to allow flow variation down
to 50 percent ofdesign flow rates. The 1999 edition also has a requirement that, for systems with more than 100 feet ofpumping head and motors greater than 50 horsepower power, consumption at 50 percent flow, be no
more than 30 percent ofdesign flow. This will effectively require variable speed pump drives on these large pumping systems. Exceptions are made for pumps less than 75 horsepower wherereduction offlow wouldbe below the minimum flow requirements for heating ventilation and air-conditioning equipment andfor systems that include

no more thanthree control valves. Significant energy savings will result from application ofthe 1999 edition in larger pumping systems due to these part-load performancerequirements.

16. Temperature Reset Controls

The 1989 editionrequires system temperature reset controls on both multi-zone air systems and large, nonvariable-flow hedonic systems. These controls shallbe capable ofproviding a reset ofat least 25 percent ofthe design supplyto room air temperature difference, with some exceptions, most notably for low zone flow rates or for systems not capable ofproviding reheat. The primary purpose ofthis requirement is to reduce reheat in air systems. Supplywater temperatures must also be capable ofa reset equivalentto 25 percent ofthe design supply-to-return water temperature difference. This requirement does not apply to hydronic systems that can provide a 50 percentreduction in system flow, or are less than 600,000 Btu perhour in capacity. Nor does it apply to reset controls that would cause improper operation ofheating, cooling, humidification, or dehumidification systems. The 1999 editionrequires reset on chilled andhotwater temperature controls used for heating ventilation and air-conditioning systems more than 300,000 Btu per hour design capacity. Direct energy savings are expected from thereset ofthe supply water temperature from chiller and boiler, and the air supplytemperatures inthe system are assumed to follow the water temperature reset. An exception is made for hydronic systems that use variable flow to reduce pumpingenergy, or for systems where reset would cause improper operation ofheating, cooling, humidification or dehumidification systems. Overall, there is little net change inthe reset requirements for hydronic systems other than the 1999 edition applying them to more systems.

The 1999 editionremoves the air supply reset requirements, while directly addressing simultaneous heating and cooling. This is addressed by better limiting the amount ofair reheated orrecooled and is set forth in

a new section ofthe standard (see Simultaneous Heating and Cooling Controls above). Some minimal degradation in efficiency is expected from removal ofthe supply air reset requirements, butthis is likely to be mitigated by the increase in efficiency from requiring reset on smaller hydronic systems.
17. Hot Gas Bypass Restriction

The 1999 edition introduces a new requirementthatrestricts the use ofhot gas bypass in cooling equipment unless the equipmentis designed with multiple steps ofunloading. In the latter
case, hot gas bypass is allowed, but maximum hotgas bypass levels are specified as a fraction oftotal capacity for different sizes ofcooling equipment. This requirement will provide an improvement in part-load performance for cooling equipment, where manufacturers are not already incorporating multiple steps of unloading.

18. Heating Ventilation and AirConditioning Equipment

The 1999 edition provides updated equipmentefficiency requirements with

an effective date ofOctober 29, 2001. Tables 6.2.lA-6.2.lG ofthe 1999 edition show the existing 1989 edition's heating ventilation and air-conditioning equipmentefficiency requirements (shown inthe "minimum efficiency" column) with the 1999 edition's update requirements shown in the "Efficiency

as ofOctober 29, 2001" column in each table across heating and cooling product categories. Where the 1999 edition has equipmentefficiency requirements but the 1989 edition does not (as is the case with absorption and heatrejection equipmentfor example) increased energy efficiency occurs unless the requirements are set at orbelow

common practice. In these cases, we used ASHRAE's assessment ofthe minimum performance ofthe equipment used in common practice as
a baseline. A summary ofthe shipped capacity weighted efficiency improvements across generic product categories is shown in Table 14.

TABLE 14.-SHIPPED CAPACITY

WEIGHTED EFFICIENCY IMPROVEMENT ACROSS GENERIC PRODUCT CATEGORIES, INCLUDING EQUIPMENT SHIPMENTS TO COMMERCIAL BUILDINGS COVERED BY FEDERAL MANUFACTURING STANDARDS

Equipment category

Unitary Air Conditioners

and Condensing Units Unitary and Applied Heat

Pumps

......................... Electrically Operated

Water Chillers

............. Absorption Chillers

......... Packaged Terminal Air

Conditioners and Heat Pumps

......................... Room Air Conditioners

... Furnaces, Duct FurEstimated full load efficiency improvement (in percent)

7

9.2

16.8 5.2+

22.4 10.1

naces, Unit Heaters

.... Boilers

............................. O+ 0

The absorption chillers 5.2 percent estimated full load efficiency improvement is based on double effect chillers. The 1989 edition had no efficiency requirementfor absorption chiller equipment. Based on an industry derived market baseline for double effect chillers provided during the development ofthe 1999 edition, the 1989 edition's performance coefficient is 0.95. Therefore, selection ofthe 1999 edition's coefficient ofperformance of 1.0 will provide improved efficiency. Improvements ofup to 25 percent above market minimums are estimated for single effect equipment.

The full load efficiency improvement in room air-conditioners in the 1999 edition were adopted from the Department's manufacturing standard requirements, effective October 1, 2000 (10 CFR 430). These efficiency improvements cannotbe attributed to the improvedrequirements ofthe 1999 edition.

For furnaces, duct furnaces, and unit heaters, changes were made to test procedures and efficiency descriptors for unitheaters, but no net change was

### 46484 

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices

made in efficiency inthe 1999 edition. Improved prescriptive requirements in the 1999 edition for warm-air furnaces such as requirements for intermittent ignition or interrupted device andjacket loss limits, will improve annual efficiency.

For boilers, the full loadthermal efficiency descriptor was improved in the 1999 edition,butnot the boiler efficiency requirements. The 1999 edition's requirements for thermal efficiency willremove some boilers from the marketthat currently meetthe single 80 percent combustion efficiency requirement inthe 1989 edition, and have thermal efficiencies ofless than 75 percent. This is particularly true of
steamboilers.

In addition to providing updated efficiency requirements for most commercial equipment, the 1999 edition subdivides several ofthe original 1989 edition product categories and adds new efficiency requirements for heat rejection equipmentthat were not covered underthe 1989 edition. The 1999 edition provides coefficient of performance and integrated part-load value requirements for centrifugal chillers operating at other than nominal
test conditions. It also expresses efficiency requirements, for boilers less than or equal to 2.5 million Btu per hour inputrating, using true thermal efficiency, as opposedto combustion efficiency requirements inthe 1989 edition. The 1999 edition provides separate efficiency requirements for packaged terminal air conditioner and packaged terminal heat pump equipment. The 1999 edition also updates efficiency requirements to reflect changingtest procedures and mandates the use ofeither intermittent

or interrupted ignition devices and power venting or flue dampers on forced air furnaces. Finally, the 1999 edition restrictsjacketlosses on gas and electric furnaces located outsidethe conditioned space.

The 1999 edition provides significant improvementto cooling equipment efficiencies, and minorincreases in average oil or gas space heating equipmentefficiency due to a change in eitherefficiency designator or shell loss requirements. It also provides for a moderate increase inheat pump heating side efficiency. All ofthese requirements (except for room airconditioners) will improve thegeneral efficiency ofcommercial space conditioning products beyond that required in the 1989 edition and will thus contributeto energy savings with the 1999 edition. 19. Service Water Heating Equipment Efficiency

The 1999 edition sets service water heating (SWH) equipmentefficiencies for gas and oil fired equipment at, or moderately higher than, the 1989 edition levels. Itimproves thermal efficiencies from two to three percentage points for gas water heaters with integral storage, and improves thermal efficiencies one percent for oil fired instantaneous water heaters with integral storage, as well as for the similarly defined category of "hotwater supply boiler."

For the 1999 edition, the general form ofthe equations for standby loss for oil andgas water heaters were slightly modified andrewritten to include a fuel inputrating variable and the definition ofthe volume inthe equation. In the 1989 edition, the standby loss was purely a function ofvolume. With the modification in the 1999 edition ofthe standby loss equation, standby loss is

now a function ofboth volume and inputrating. Forgas and oil water heaters, the stringencies ofeach standard are roughly the same within each ofthe individual product categories. This allows somewhat more standby loss for large inputrating products and allows somewhat less standby loss for smaller inputrating products. Without very detailed information about the shipped quantity ofproducts within a size category, itis unknown whether there is a net change in efficiency. For electric water heaters greater than 12 kilowatt input, the 1999 edition does appear to allow marginally greater standby loss, as the formula is based onrated as opposed to measured volume. This allows a ten percent variation between the rated and measured volume. However, since this product is covered by a Federal national manufacturing standardthat is more stringent than the requirements ofthe 1999 edition and the federal standard preempts state or local regulation, the reduced stringency in the 1999 will not reduce energy efficiency.

20. Service Water Heating Controls

Both the 1989 and 1999 editionhave requirements for a minimum service hot
water temperature control capability set point. as well as a maximum control temperature requirement for public
restrooms of 110 degrees Fahrenheit. Since these are only capability and not set pointrequirements, no change in net building energy use is expected or assured. The 1989 edition also has a requirement that booster heaters be installed where outlet temperatures of

more than 120 degrees Fahrenheit were required, which is absent in the 1999 edition. The energy impact ofdropping this requirement is highly dependent on the fuel source usedby thebooster heater. Generally, a slightincrease in site energy use in specific applications mightbe expected, however, there may also be a corollary reduction in source energy use occurring from thereduced

use ofelectricbooster heaters (a cheap first cost alternative to meeting the 1989 editionrequirement). The netimpact on hot water energy use is expectedto be minimal.

D. Energy CostBudget

Forboth editions, the Energy Cost Budget section provides a wholebuilding tradeoffmethodologyto allow innovative or uniquebuildings to comply withthe standard. TheEnergy Cost Budget sectionrequires the designer to simulateboth a baseline buildingthat complies withthe standard and the actual design being proposed. The design building is not allowed to have a greater energy cost thanthe baseline buildingthat complies withthe standard. Neither edition ofthe standard allows designs to exceed the base standard, and as such, the stringency ofthe Energy Cost Budget method in each edition is roughly equivalent to the stringency that would be achieved ifthebuilding complied with the prescriptive requirements of the respective editions ofthe standard.

E. Conclusion AboutDetailed Textual Analysis

Our assessment ofseven areas of change inthe Lighting and Power sections ofthe two editions leads us to concludethat there will be a net positive increase ofefficiency in commercial buildings from these revisions. Conversely. our assessment of the eleven areas ofchange inthe Envelope section ofthe two editions leads us to conclude that there willbe

a net decrease in efficiency of commercial buildings due to these changes. Finally, ourreview ofthe 22

areas ofchange intheMechanical Equipment and Systems sections ofthe
two editions leads us to concludethat theserevisions will produce a net positive increase in the efficiency of commercial buildings.

We therefore conclude from our detailed textual analysis thatthere will be a modest netgain from the changes.

IV. Filing Certification Statements with DOE

A.Reviewand Update

On the basis oftoday's DOE determination, each State is required to

### Federal Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices 46485

review and update the provisions ofits commercialbuildingcodeto meet or exceedthe provisions ofthe 1999 edition for any "building" within the meaning ofSection 303(2) ofthe Energy Conservation andProductionAct, as amended. This action mustbe taken not later than two years from the date of today's notice, unless an extension is provided. Section 304(b)(2)(B)(i) and (c).

The Departmentrecognizes that some States do nothave a State commercial buildingcode or have a code that does
not apply to all commercialbuildings. If local building codes regulate commercial building design and construction rather than a State code, the State mustprovide for review and update ofthose local codes to meet or exceed the 1999 edition. States may base their certifications onreasonable actions by units ofgeneral purpose local government. Each such State must still review the information obtained from the local governments and gather any additional data and testimony for its

own certification.

States shouldbe aware thatthe Department considers high-rise (greater than three stories) multi-family residential buildings andhotel, motel, and other transient residential building types ofany height as commercial buildings for energy code purposes. Consequently, commercialbuildings, for the purposes ofcertification, would include high-rise (greater thanthree stories) multi-family residential buildings and hotel, motel, and other transientresidential buildingtypes of any height.

B. Certification

Section 304(b) ofECPArequires each State to certify to the Secretary of Energy that it has reviewed and updated the provisions ofits commercial building code regarding energy efficiency to meet or exceed the 1999 edition. The certification must include a demonstration that the provisions ofits commercial building energy code regarding energy efficiency, meet or exceed Standard 90-1999 for any "building" withinthe meaning of Section 303(2) oftheEnergy Conservation and ProductionAct, as amended. Ifa State intends to certify that its commercial building code already meets or exceeds the requirements ofthe 1999 edition, it would be appropriate for the State to provide an explanation ofthebasis for this certification, e.g., the 1999 edition is incorporatedby reference in the State's buildingcode regulations. The Department believes that it wouldbe appropriate for the chiefexecutive of the State (e.g., the Governor) to designate a State official, such as the Director ofthe State energy office, State code commission, utility commission,

or equivalent State agency having primary responsibility for commercial building codes, to providethe certificationto the Secretary. Such a designated State official could also provide the certifications regardingthe codes ofunits ofgeneral purpose local governmentbased on information providedby responsible local officials.

C. Requestfor Extensions

Section 304(c) ofECPArequires that the Secretary permit an extension ofthe deadline for complying with the certificationrequirements described above ifa State can demonstrate that it has made a good faith effort to comply with such requirements and thatit has made significant progress toward meeting its certification obligations. Such demonstrations could include one

or more ofthe following: (1) A plan for response to the requirements stated in section 304; or (2) a statement that the State has appropriated or requested funds (within State funding procedures)
to implement a planthat would respond
to the requirements ofsection 304.

D. Submittals

When submitting any certification documents inresponse to this notice, the Departmentrequests that the original documents be accompanied by

one copy ofthe same.

Issued in Washington, DC, onJuly 8, 2002. David K. Garman,
AssistantSecretary forEnergyEfficiencyand RenewableEnergy. AppendixA. Description ofProposed Analysis

At the February workshop we explained that the proposed analysis would provide qualitative comparisons ofthe stringencies between the two editions ofStandard 90.1 in: (1) The scope ofthe standard: (2) the building envelope requirements; (3) the building lightingrequirements; (4) thebuilding mechanical equipmentrequirements; and (5) the paths to compliance.

We stated that the proposed emphasis of the qualitative comparison would differ between the envelope, lighting, and mechanical sections. In the building envelope section, the comparison would focus onthe impact ofthe different building envelope requirements onthebuilding heating and cooling loads for different building types and climates. The envelope comparisonwould examine requirements for all envelope components, includingroofs, walls, floors, and fenestration as well as explore variations in construction types and in the window-to-wall ratio.

In the lightingrequirements comparison,

we explained that the proposed focus would be primarily onthe impact the different lightingrequirements have onlighting energy use, as well as onbuildingloads. The comparison would look separately atthe wholebuilding and space-by-space lighting requirements in a variety ofcommercial buildingtypes, as well as examine the effect ofany "additional lighting power allowances."

We proposed that the mechanical requirements comparisonbe divided into comparisons ofequipment efficiency requirements and system design requirements. We explainedthat the system designrequirements affect boththe system efficiency and system load impacts, and may have direct energy impacts as well. We also proposed that tables ofrelative stringency and estimated positive or negative national energy impactbe preparedbased on practical application ofthe system design requirements in each standard.

We explained that each standard has multiple ways to demonstrate compliance. We proposed to enumerate the multiple paths to compliance,but did not propose to perform a detailed comparison ofthe relative stringency ofalternate paths internal to a single standard orbetween standards. We explainedthat the large quantity ofvariables among the alternative compliance paths would make such analysis prohibitive to undertake. Further, we explained that we knew ofno data onwhichto base the selection ofrepresentative requirements for such an analysis. Assignment of requirements wouldbe arbitrary. Rather we proposed to focus on what webelieved is the
most common approach to usingthe standard in question for particularbuildingtypes.

Addressing the quantitative analysis, we proposed to base the quantitative comparison ofenergy codes on whole building energy simulations ofbuildingsbuilt to each standard. We proposed to simulate seven representative buildingtypes in 11 representative U.S. climates. The simulated buildings would utilize the 15 zonebuilding prototypes used inprevious DOE building research, and the energy use intensities for each zone from the simulations wouldbe scaled to correctly reflect variations in characteristic building sizes and shapes for each representative building type. Energy Use Intensities (EUis) developed for each representative buildingtype wouldbe weighted by total national square footage in eachrepresentative building category to provide an estimate ofthe national energy savings.

We noted that only changes to requirements for newbuildings would be considered in this quantitative analysis. Appendix B. Description ofthe Quantitative Analysis

The analysis methodology is briefly describedbelow. This is followed by a description ofthe input assumptions.

I.Analysis Methodology

To determine the aggregate impact of changes to the envelope, lighting, and mechanical sections of90.1. a series of building simulations were made using the BLAST (Building Loads Analysis and System Thermodynamics) building simulation

### 46486 

### Federal 

### Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices

software. Sevenbuildingtypes, shown in Table 15, were used inthe analysis. These

seven buildingtypes used represent approximately 80 percent ofcommercial buildingenergy consumption, according to the Energy Information Administration's 1995 Commercial BuildingEnergy Consumption Survey (CBECS95) data. (The Office buildingtype includes Outpatient Health Care at 76.6 thousand Btu peryear.)

TABLE 15.-ENERGY CONSUMPTION BY PRINCIPAL BUILDING ACTIVITY (TRILLION BTU)

Building types simulated Annual energy
use Percent of total

Office

........................................................................................................................................................................ 1,095 973 614 461 449 332 325 20.6 18.3 11.5 Mercantile and Service

............................................................................................................................................ Education

................................................................................................................................................................. Lodging

.................................................................................................................................................................... 8.7 8.4 6.2 6.1 Public Assembly

...................................................................................................................................................... Food Service

............................................................................................................................................................ Warehouse and Storage

..........................................................................................................................................
Total for above Categories

............................................................................................................................... 4,249**!--~~~~~-+~~~~~~** Total for all commercial buildings

..................................................................................................................... 5,323 79.8

Construction variation within each building category was simulated using four different window to wall area ratios, both

mass (such as dense masonry) and light frame wall constructiontypes, and gas and electric heatingfuel types. Two scenarios of economizer usage were simulated in each climate to account for the variation of economizer usage requirements in combination with equipment size. The buildings were simulated in 11 different

Location HDD 65

Denver, CO

...................... 6083 Detroit, Ml
························ 5997 Fresno, CA

....................... 2700 Knoxville, TN

.................... 3818 Los Angeles, CA

.............. 1494 Minneapolis, MN

.............. 8060 Orlando, FL

...................... 532 Phoenix, AZ

..................... 1382 Providence, RI

................. 6022 Seattle, WA

...................... 5281 Shreveport, LA

................. 2265 Tampa, FL

........................ 575

In addition to simulatingbuildings that complied with the 1989 and 1999 editions, the changes in envelope. lighting and mechanical requirements were each separately simulated, without changingthe 1989 edition'srequirements for the other components. Then, because the lighting and envelope requirements impact each other, particularlyin the 1989 edition, the combined lighting and envelope requirement differences were analyzed, again without changing the 1989 edition's requirements for the other components. Calculating the difference between this combination and all 1999 edition requirements allowed an assessment ofthe impact ofthe mechanical changes after adjusting for this thermal load shift. In all, six separate sets ofrequirement changes were simulated. climate locations (Table 16). The climate locations were chosenbased on statistical cluster analysis of234 Typical Mean Year weather data tapes and were chosen to be representative ofthe variation in climate found in the U.S. Several ofthe more significant climate parameters are shown in Table 16. These include, HeatingDegree Days, base 65 degrees Fahrenheit (HDD 65); Vertical Solar radiation, inthe North (VSN). East/West (VSEW). and South (VSS) orientations; CoolingDegree Day, base 50 degrees Fahrenheit (CDD 50); minimum recorded outdoortemperatures for 99.6 percent ofthe time for heating design calculations; maximumrecorded Dry Bulb (DB) outdoortemperatures exceeded 1 percent ofthe time for cooling design calculations; and maximumrecorded Wet Bulb (WB) outdoor temperatures exceeded

one percent ofthe time, also for cooling design calculations.

TABLE 16.-CLIMATES LOCATIONS USED

Cooling Cooling Heating VSN VSEW 

### vss CDD 50 design (1% design 1% design 99.6 DB) WB)

428 971 1321 2611 3 90 59 390 676 858 3199 0 87 72 459 1029 1199 5070 30 101 70 446 762 898 4455 13 90 74 482 962 1146 4456 43 81 64 380 709 972 2751 16 88 71 511 881 974 8288 37 93 76 488 1116 1310 7830 34 108 70 393 677 874 350 621 828 484 843 954 518 890 974

In total, 2464 simulations were performed for each set ofrequirement changes. A prototypical 48,000 ft2

, 15-zone, slab-ongrade building was used for all the simulations. Simulationresults for this prototypicalbuilding size were then scaled to reflect aggregate energy use inbuildings

across a wide range ofsizes and shapes using Commercial Building Energy Consumption Surveybuilding data. Single zone airconditioning and heating systems were assumed in the buildingmodel to permit this scaling. This simplification should result in

a lower-bound estimate ofenergy savings with the standard as explained in mechanical system characterizationbelow. 2756 5 86 71 1683 23 81 64 6022 22 95 77 7985 36 91 77

II. SimulationInputCharacterization

A. Envelope

Thebuilding envelope characteristics examined in the analysis were the opaque wall and roofU-factors, the fenestration Ufactors, eitherthe fenestration Shading Coefficient requirements (in the 1989 edition)

or SolarHeat Gain Coefficient requirements (in the 1999 edition), and the effective slab U-factors for slab on grade construction. These characteristics were determined for each set ofrequirement changes, building type, and climate combination simulated.

The 1989 edition's envelope requirements simulated were based onthe 1989 edition's Alternate Component Packages (ACP) tables. These tables represent the prescriptive compliance pathfor the 1989 edition's envelope requirements. Because the 1989

### Federal Register I

### Vol. 67, No. 135 I

### Monday, July 15, 2002 I

### Notices 46487

edition'srequirements do not necessarily reflect the performance oftypicalbuilding assemblies, the actual U-factors used inthe simulations were chosen to reflect the Ufactors ofrealbuilding assemblies whichbest approach, withoutbeingless stringent than, the U-value requirements ofthe standard. This is expected tobe more representative of the real envelope performance resulting from application ofthe 1989 edition. Note thatby being more stringent than the U-factor requirements, this procedure provides a conservative estimate ofthe envelope energy savings.

In addition, the 1989 edition's ACP tables represent more stringent envelope requirements thanthat specified for most climates or buildings, usingthese equations outlinedin Chapter 8 ofthe 1989 edition. The equations are embodied inthe ENVSTD, version 2.4, software. For this reason. the use ofthe ACP tables as the basis for the 1989 edition's envelope provides a lower boundary to the estimate ofenergy savings from thebuilding envelope requirements.

B. Lighting

The lighting power density requirements

were developed from the whole building lighting requirements for boththe 1989 and 1999 editions, for comparable buildingtypes, where available. The 1999 edition provides single value wholebuildinglighting power density values for 31 differentbuildingtypes. The 1989 editionprovides wholebuilding lighting power density values for only 11 differentbuildingtypes. However, it provides different lighting power densities for six differentbuilding size categories within each buildingtype. In neither case do the whole building lighting power density values correspond perfectly to thebuildingtypes simulated. The following procedure was used
to develop whole building lightingnumbers for each ofthese categories.
1. Lighting Power-1989 Edition

For office and warehouse buildingtypes, where there is a direct matchwith the 1989 standard whole buildinglighting power categories, the lighting power density was estimated by weightingthe whole lighting power density across the sixbuilding size categories by the fraction ofeachbuilding type's floor space in each size category using CBECS95 data. In the case ofFood Service andEducation, the 1989 editionprovides lighting power density values for subcategories ofthese building types. Food Service is composed of Fast Food/Cafeteria and Leisure Dining/Bar subcategories, Education is composed of Preschool/Elementary, Jr. High/High School. and Technical/Vocational subcategories. In these cases, first the lightingpower densities for the different building sub types were averaged together for eachbuilding area category. Then, a weighting ofthese new lighting power densitiesbybuildingsize category was made, using CBEC's data for Food Service orEducationbuildingtypes, as appropriate.

In the case ofretail typebuildings, the 1989 edition has threebasic retailbuilding subcategories, Retail, "Mall Concourse, and "Service. Commercial BuildingEnergy Consumption Survey floor area data is categorized as Enclosed ShoppingCenter/ Mall, Retail (except Mall), Service (except Food), and Strip Shopping. To make a realistic weightingbyretail type the following allocation ofCommercial Building Energy Consumption Survey retail type floor

area was made.

TABLE 17.-ALLOCATION OF CBECS95 RETAIL TYPE FLOOR AREA

Retail building categories-1989 edition

Retail

.........................

Mall Concourse

.........
Service

...................... Allocation of CBECS95 building category floor area

Retail (except Mall)

plus Strip Shopping plus half of Enclosed Shopping/ Mall. Half of Enclosed

Shopping/Mall. Service (except

Food).

Then a weighted average ofthe allowed lighting power densities was constructed, using the 1989 edition's lighting power density values and the CBECS95 floor area data for eachbuilding type and size category.

For Lodging and Public Assembly building types, the 1989 edition has no direct match in the whole building lighting power density

TABLE 18.-LIGHTING POWER DENSITY [Watts/ft2]

Building type tables. For a comparison ofthesebuilding types, the 1989 edition's wholebuilding lighting power density values were developedby applying the appropriate 1989 edition's space-type lighting power density values (with appropriate Area Factor adjustments) to the building specific space type square footage data used inthe development ofthe 1999 editionlighting
power densities. The 1989 editionbuilding specific space type data models the actual weighting ofspace type square footage, within a specific buildingtype, based on actual current U.S. construction data. The lighting power density value for the Lodging category is made up ofthe average ofthe whole buildinglightingpower densities constructed for the 1999 edition'sbuilding categories: Dormitory, Hotel, and Motel. The lighting power density value for the Public Assembly categories is similarly made up of the average 1999 edition's wholebuilding lighting power density values for Convention Center, Motion Picture Theater, Performing Arts Theater, Town Hall, Sports Arena, Museum, and Gymnasium.
2. Lighting Power-1999Edition

The 1999 edition provides single value, whole building, lightingpower density requirements for Office, Retail, Education, and Warehousebuildings, and these requirements were used inthe simulations. The 1999 edition does not provide single lighting power density values for Food Service, Lodging, orPublic Assembly buildings. For these cases, the average whole building lighting power density requirements, for building types falling in each category, was taken to form a single lighting power density requirement. In these

cases, the same specific buildingtypes used
to develop the 1989 edition's lighting power density values were used to derive the 1999 edition's lightingpower densities for Lodging and Public Assembly building types. The 1999 edition's Food Service value was derived as the average ofthe 1999 edition's three whole building food service building type values.

Table 18 shows a comparison ofWhole Building lightingrequirements underboth editions.

1989 edition 1999 edition

Education

..................................................................................................................................................... 1.79 1.62 1.53 1.63 1.72 2.36 0.53 1.50 1.73 1.73 1.30 1.53 1.90 1.20 Food Service

................................................................................................................................................ Lodging

........................................................................................................................................................ Offices

.......................................................................................................................................................... Public Assembly

.......................................................................................................................................... Retail

............................................................................................................................................................ Warehouse/Storage

.....................................................................................................................................

C. Mechanical Equipment

Single zone cooling and heating systems

were used inthe analysis. The choice of single zone system inthe analysis is expected
to provide a lowerboundary to ourestimate ofcooling energy savings. First, this is because the improvement in the 1999 edition's average efficiency requirements, for single zone cooling systems (typically unitary equipment), is relatively small compared to that for typical central system cooling equipment (typically water chillers). This is

more obvious when onerealizes that shipments ofall products to commercial buildings includesresidential type cooling

### 46488 Federal 

### Register/Vol. 67, No. 135/Monday, July 15, 2002/Notices

products shippedto small commercial buildings. Additionally, modeling single

zone systems does not take into account the fact that the 1999 editionhas introduced requirements for central system heat rejection equipment, where none existed inthe 1989 edition. There is relatively little improvement inheating equipment efficiency requirements, inthe 1999 edition, for equipmentused in single zone systems (typically furnaces), or central systems (typically boilers). The impact ofthe 1999 edition onheating energy use will typically be determined principallyby changes in heatingloads ratherthan heating equipment efficiency.

1. Cooling Equipment

Cooling equipment efficiencies were developedby weighting the energy efficiency ratingfor each of 20 categories ofsingle zone cooling equipmentinthe standard, by an estimate ofshipped cooling capacity for each category. The primary source ofshipping data was 1998 U.S. Census Data. In the case ofthe less than 65,000 Btu perhour unitary air source heat pumps and air conditioners, this census data was augmented by our interpretation ofAir-Conditioning and Refrigeration Institute and Lawrence Berkeley National Laboratory data on single phase air-conditioners and heat pumps shipped to commercialbuildings. Using the weighting information and equipment efficiencies in each edition, the average unitary equipment efficiency requirement for commercialbuildings increased 7.5 percent, from an average energy efficiency ratio of from 9.28 to 9.98. This improvement was simulated for all buildingtypes except Lodging. ForLodging, it was assumed that the majority ofsingle zone cooling equipment wouldbe packaged terminal equipment. The average efficiency requirement for packaged terminal equipmentincreased 22 percent, from 8.4 to 10.28,based on a shippedcapacity weighting. These efficiencies were used in the Lodging simulations for the respective Standard levels.
2. Space Heating Equipment

No change inheating equipment combustion efficiency is required inthe 1999 edition. However, for commercial furnaces, a reduction in the loss through the equipment casing from 1.5 percent to 0.75 percent was modeled to reflect differences inthe requirements inthe two editions. No change in furnace casing losses was assumed where electric resistance heat was assumed.
3. Economizers

For eachbuildingtype, simulations were madeboth assuming economizer operation and not assuming economizer operation. Based onthe economizer requirements in each edition and the available cooling equipment shipment data, shipped cooling capacity weights were developed for systems requiring economizer usage ineach climate.
4. Service Water HeatingEquipment

Service water heating equipment efficiencies increased from 78 percent to 80 percent for mosttank-type gas fired water heaters. This was reflected inthe input assumptions. We did not account for shipments ofresidential size waterheating equipment (regulated by manufacturing standards under Subpart C of 10CFR 430) to commercial buildings. While these units may be used in some commercialbuildings, increased efficiencies are the result of regulatory actions under 10 CFR 430, not Standard 90.1. Nor did we account for the

use oftankless instantaneous water heaters in commercial buildings. Correctly accounting for shipped capacity ofboth the residential size and tankless equipment to commercial buildings wouldreduce the average efficiency improvement somewhat, but
accurate shipment data to commercial buildings is largely unavailable.

No change inwaterheater standby loss efficiencies was modeled. Forfossil fuel fired equipment, the standby loss efficiencies within a given size category are essentially the same. While a different formulation ofthe standby loss equations was used inthe 1999 edition, there are both standby loss increases and decreases in any given product category. We are unaware ofa data base that categorizes this data to permit accurate estimation ofa netresult. For electric water heaters, there appears tobe a reduction in standby loss efficiency inthe 1999 edition. However, the Energy Policy and Conservation Act, as amended, does not permit the manufacture or sale ofthese lower efficiency products. Therefore, there is no predicted impact on actualbuildings.

D. Aggregation of Results Aggregation to a national estimate of
energy use isbased on energy use intensities (EUI) developed from simulations, under each edition. Aggregation ofenergy use intensity from the simulations was done as follows: (1) Extract zone-based energy use intensities from simulations; (2) aggregate results byrequired economizer usage ineach climate; (3) map simulationresultsby climate to 11 geographical areas (augmented

census divisions); (4) scale simulationresults
to existingbuilding stock floor area by building type and census region; (5) weight results for frame and mass wall construction by appropriatebuildingtype and census region weights for these types of construction; ( 6) weight results for heating fuel by augmented census division weights for electric resistance heatingusage in commercial buildings (Commercial Building Energy Consumption Survey data); (7)
convert energy use intensities by fuel type to site energy, source energy, and energy cost intensities, bybuildingtype, and augmented

census division; (8) weight energy use intensity results by building construction floor area estimates, by buildingtype and in each augmented census division. The building construction data was derived from the Energy Information Administration's National Energy Modeling System data sets. [FR Doc. 02-17637 Filed 7-12-02; 8:45 am]

BILLING CODE 6451Hl1-P DEPARTMENT OF ENERGY

Federal Energy Regulatory Commission

[Docket No. ER02-2126-001]

Consolidated Edison Company of New York, Inc.; Notice of Filing

July 9, 2002.

Take notice that on June 28, 2002, ConsolidatedEdison Company ofNew York, Inc., (Con Edison) submitted for filing a revised unexecuted Interconnection Agreementbetween ConEdison and PSEG Power In-City I, LLC (PSEG Power) making a minor correction to the filing made onJune 20, 2002. This filing is made to correct a formatting error inthe table ofcontents ofthe agreement.

Any person desiring to intervene or to protestthis filing should file with the Federal Energy Regulatory Commission, 888 First Street, NE., Washington, DC 20426, in accordance withrules 211 and 214 ofthe Commission's rules of practice and procedure (18 CFR 385.211 and 385.214). Protests willbe consideredby the Commission in determining the appropriate action to be taken. but will not serve to make protestants parties to the proceeding. Any person wishing to become a party mustfile a motion to intervene. All such motions or protests should be filed on

or before the comment date, and,to the
extent applicable, mustbe served on the applicant and on any otherperson designated on the official service list. This filing is available for review at the Commission or may be viewed onthe Commission's web site at http:// 

### www.ferc.govusing the "RIMS" link, select "Docket #" and follow the instructions (call 202-208-2222 for assistance). Protests and interventions
maybe filed electronically via the Internetin lieu ofpaper; see 18 CFR 385.2001(a)(1)(iii) and the instructions

onthe Commission's web site underthe "e-Filing" link.



### CommentDate: July 19, 2002.

Linwood A. Watson, Jr., DeputySecretary. [FR Doc. 02-17722 Filed 7-12-02; 8:45 am]

BILLING CODE 6717-01-P