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# Walk-In Coolers and Walk-In Freezers Test Procedure Notice of Proposed Rulemaking Public Meeting

The U.S. Department of Energy (DOE) is publishing a Notice of Proposed Rulemaking (NOPR) for the test procedure rulemaking for walk-in coolers and walk-in freezers (WICF). The NOPR is the first document to be published in the test procedure rulemaking process. It will be followed by a final rule. At the NOPR stage, DOE proposes the procedures to be used to test WICF equipment for certification, compliance, and enforcement of the energy conservation standards. Interested parties are invited to review the NOPR, attend public meetings, and submit comments on DOE's approach. The following documents are available as Adobe Acrobat PDFs. Download Adobe Reader . 

## Meeting Materials z 

### Energy Conservation Program: Test Procedures for Walk-In Coolers and Walk-In Freezers, Proposed Rule, Federal Register , 75 FR 186, January 4, 2010 ( PDF 564 KB ) z 

### Energy Conservation Program: Public EERE Information Center Programs and Offices



### DATE: March 24, 2010 TIME: 9:00 a.m. – 5:00 p.m. EST LOCATION: U.S. Department of Energy Forrestal Building 1000 Independence Avenue, SW Room 8E-089 Washington, DC 20585 

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### Meeting and Availability of the Notice of Proposed Rulemaking for Walk-In Coolers and Walk-in Freezers; Date Change, Federal Register 75FR 9120, March 1, 2010 ( PDF 72 KB ) z 

### Agenda ( PDF 26 KB ) z 

### Presentation ( PDF 1.1 MB ) z 

### Transcript. A transcript will be available on this Web site after the meeting, and will also be available for public inspection in the Building Technologies Program Reading Room, between 9:00 a.m. and 4:00 p.m., Monday through Friday, except Federal Holidays. To schedule an appointment or to purchase the transcript, contact: Brenda Edwards U.S. Department of Energy Building Technologies Program 950 L'Enfant Plaza, 6th Floor Washington, DC 20024 Telephone: 202-586-2945 

## How to Submit Comments Interested parties may submit comments electronically, by mail, or by hand delivery or courier. Comments should clearly identify docket number EERE-2008-BT-TP-0014 . The deadline for submit ting comments is March 31, 2010. Wherever possible, comments in the electronic format should carry the electronic signature of the author. Absent an electronic signature, comments submitted electronically must be followed and authenticated by submitting the signed original paper document.
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### E-mail: wicf - 2008 - tp - 0014@ee.doe.gov Include Docket Number EERE-2008- BT-TP-0014 and/or RIN 1904- AB85 in the subject line of the message. z 

### Postal Mail: Brenda Edwards U.S. Department of Energy Building Technologies Program 1000 Independence Avenue, SW Mailstop EE-2J Washington, DC 20585 

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### Building Technologies Program Home | EERE Home | U.S. Department of Energy Webmaster| Web Site Policies| Security & Privacy | USA.gov Content Last Updated: 04/01/2010 

### Please include a signed original.
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### Hand Delivery or Courier: Brenda Edwards U.S. Department of Energy Building Technologies Program 950 L'Enfant Plaza, 6th Floor Washington, DC 20024 Telephone: 202-586-2945 Please include a signed original. 

## Contact Information CharlesLlenza Project Manager 202-586-2192 Printable Version 

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# Building Technologies Program

Test Procedures for Walk- in Coolers and Freezers Notice of Proposed Rulemaking March 24 , 2010

2 | Building Technologies Program eere.energy.gov 

### Table of Contents

Background & Approach

2 Basic Model 3 Proposed Test Procedure – Envelope 4 Proposed Test Procedure – Refrigeration System 5 Impacts on Small Businesses 6 Others Issues/Closing Discussion 7 Overview of Public Meeting 13 | Building Technologies Program eere.energy.gov 

### Table of Contents

Background & Approach

2 Basic Model 3 Proposed Test Procedure – Envelope 4 Proposed Test Procedure – Refrigeration System 5 Impacts on Small Businesses 6 Others Issues/Closing Discussion 7 Overview of Public Meeting 1

4 | Building Technologies Program eere.energy.gov 

### Overview >> Welcome 

### Welcome
• Introductions
• Role of the Facilitator
• Ground Rules (norms)

– Listen as an ally

– Use short, succinct statements/keep to the point

– Hold sidebar conversations outside the room

– One person speaks at a time (raise hand to be recognized; state your name for the record)

– Set cell phones to silent/vibrate 

### • Housekeeping Items
• Agenda Review
• Opening Remarks5 | Building Technologies Program eere.energy.gov 9 : 00 – 9 : 15 am Welcome and Introductions 9 : 15 – 9 : 30 am Rulemaking Overview 9 : 30 – 10 : 00 am Opening Remarks from Interested Parties 10 : 00 – 11 : 00 am Test Procedures Approach 11 : 00 – 11 : 15 am Break 11 : 15 – 12 : 30 pm Proposed Envelope Test Procedure 12 : 30 – 1 : 30 pm Lunch 1 : 30 – 3 : 15 pm Proposed Envelope Test Procedure, continued 3 : 15 – 3 : 30 pm Break 3 : 30 – 4 : 30 pm Proposed Refrigeration System Test Procedure 4 : 30 – 4 : 45 pm Discussion of Small Business Impacts 4 : 45 – 5 : 00 pm Other Issues; Questions & Comments; Closing Remarks 5 : 00 pm Adjourn 

### Overview >> Agenda

6 | Building Technologies Program eere.energy.gov 

### EPCA Provision Authority Effective Date Details Prescriptive Standards Congress January 1, 2009 DOE does not have the authority to alter these prescriptive standards. Test Procedures DOE 30 Days After Test Procedure Final Rule Publication This is the subject of today‘s

rulemaking. Energy Conservation Standards DOE 3 Years After Standards Final Rule Publication This is being addressed in a separate DOE rulemaking. 

### EPCA Provision Authority Effective Date Details Prescriptive Standards Congress January 1, 2009 DOE does not have the authority to alter these prescriptive standards. Test Procedures DOE 30 Days After Test Procedure Final Rule Publication This is the subject of today‘s

rulemaking. Energy Conservation Standards DOE 3 Years After Standards Final Rule Publication This is being addressed in a separate DOE rulemaking. 

### Background & Approach >> Overview



###  Test procedures and energy conservation standards set by DOE are separate from the prescriptive standards set by EPCA. DOE is conducting this rulemaking as required by law.

• The Energy Independence and Security Act of 2007 ( EISA 2007 ) amended the Energy Policy and Conservation Act ( EPCA) to add provisions for WICF.7 | Building Technologies Program eere.energy.gov 

### Background & Approach >> Overview 

### The test procedure and standards rulemakings are currently at different stages.
The test procedure NOPR is the subject of this public meeting. NOPR Final

Rule Test Procedure Milestones

Framework Prelim.

Analysis NOPR Final Rule Standards Milestones The energy conservation standards rulemaking is in the preliminary analysis stage. The standards preliminary analysis results will be presented in a separate public meeting.

8 | Building Technologies Program eere.energy.gov 

### Major Milestones NOPR Final Rule

• NOPR published: January 4, 2010 (75 FR 186 ).
• NOPR public meeting: March 24, 2010 (today).
• NOPR comments due: March 31, 2010 (one week from today).

– Transcript records oral comments from today‘s public meeting.

– Written comments. • DOE reviews and considers all comments. 

### Overview >> Rulemaking Milestones9 | Building Technologies Program eere.energy.gov 

### Following publication of the notice of proposed rulemaking (NOPR), DOE is holding this public meeting: Overview >> Purpose of the Public Meeting



### • To present DOE‘s proposed test procedures for walk - in coolers and freezers (WICF or walk - ins ).

• To clarify any questions about DOE‘s proposed approach.

• To seek comment from participants on the proposed test procedure.



### • To describe the next steps for the rulemaking.

10 | Building Technologies Program eere.energy.gov 1. Background & Approach 1. Separate Test Procedures for Envelope & Refrigeration System 2. Testing Responsibilities* 3. Definition of Envelope 4. Definition of Refrigeration System 2. Basic Model 1. Basic Model of Envelope 2. Daily Energy Consumption Coefficients 3. Basic Model of Refrigeration System 4. Definition of Basic Model for Refrigeration System* 3. Proposed Test Procedure – Envelope 1. Normalization Factor 2. Proposed Test Method for Conditioning of Foam 3. Impact of Water on Foam* 4. Efficacy of Skins 5. Floorless Cooler Heat Transfer 6. Freezer Floor R - Values 7. Insulated Floor Surface Temperature Assumptions 8. Performance Data for Glass Products 9. Glass Door Energy Calculation 10. Steady- State Infiltration and Reduction Device Effectiveness 11. Calculations for Door - Opening Events 12. Infiltration Reduction Device Effectiveness 13. Electrical Duty Cycle 14. Nominal Energy Efficiency Ratio Major issues for public comment are detailed in this presentation and in Section V.E of the NOPR. 

### Overview >> Issues for Public Comment



### (Continued on Next Slide) * Did not appear in Section V.E of the NOPR11 | Building Technologies Program eere.energy.gov 4. Refrigeration Test Procedure 1. Proposed Test Procedure 2. Calculation Methodology 3. Reporting Requirements 5. Impacts on Small Businesses 1. Number of Small Entities Regulated 2. Differential I mpacts on Small Manufacturers Continued: Major issues for public comment 

### Overview >> Issues for Public Comment

12 | Building Technologies Program eere.energy.gov

Issue Box: DOE welcomes comments, data, and information concerning this proposed test procedure on walk - in coolers and freezers. Throughout this presentation, issues are provided in boxes like this one for discussion in the public meeting . While these are specific issues that DOE identified for review, comments are welcome on any part of DOE’s proposed rule . 

### Overview >> Issues for Public Comment13 | Building Technologies Program eere.energy.gov 

### Interested parties who contacted DOE to request an opportunity to make an opening statement should speak now. Overview >> Opening Statements

14 | Building Technologies Program eere.energy.gov 

### Table of Contents Overview of Public Meeting

1
Basic Model 3 Proposed Test Procedure – Envelope 4 Proposed Test Procedure – Refrigeration System 5 Impacts on Small Businesses 6 Others Issues/Closing Discussion 7 Background & Approach 215 | Building Technologies Program eere.energy.gov 

### EPCA specifies which equipment is covered by the test procedure. Background & Approach >> Overview Statutory Definition of Walk- in Coolers and Freezers:

• ― The terms  ̳walk - in cooler‘ and  ̳walk - in freezer‘ mean an enclosed storage space refrigerated to temperatures, respectively, above, and at or below 32 degrees Fahrenheit that can be walked into, and has a total chilled storage area of less than 3,000 square feet.‖ 42 U.S.C. 6311(20)(A) Walk- in Type Description of EPCA Requirement All Has a total chilled storage area of less than 3,000 square

feet. Coolers Above 32 ° F Freezers At or below 32 ° F Exceptions The definition specifically excludes ―products designed and

marketed exclusively for medical, scientific, or research purposes.‖ (42 U.S.C. 6311(20)(B))

16 | Building Technologies Program eere.energy.gov 

###  DOE proposes to develop separate test procedures for the

envelope & refrigeration system. DOE initially considered a single test procedure but changed its approach after receiving input from interested parties. Background & Approach >> Separate Test Procedures

• There are TWO components of a walk - in cooler or walk- in freezer:

– Envelope in which items are stored.

– Refrigeration system that chills the space inside the envelope.

• Feedback from Interested Parties (Standards Framework Public Meeting ) indicated that using a single test procedure was not a viable approach because:

– Could be burdensome to perform the test.

– Envelope & refrigeration system typically manufactured separately.

– Assembler or installer could be required to demonstrate compliance – not DOE‘s typical approach.

– Difficult to enforce testing requirements if the walk - in is assembled in the field.17 | Building Technologies Program eere.energy.gov 

### Background & Approach >> Separate Test Procedures



###  The purpose of the proposed test procedure is to quantitatively capture energy use in WICF as fully and accurately as possible. Separated into its distinct systems – envelope and refrigeration system – the proposed WICF test procedure follows this structure. PROPOSED TEST PROCEDURE Walk- in Coolers and Freezers Refrigeration Equipment Test Procedure [Annual Energy Use]

Net Refrigeration Capacity Annual Walk - in Energy Factor (AWEF) Envelope Test Procedure [Daily Energy Load]
Conduction Load Infiltration

Load Electrical

Load

18 | Building Technologies Program eere.energy.gov 

### Background & Approach >> Manufacturer Requirements



###  “Manufacturer” refers to either the envelope manufacturer or

the refrigeration system manufacturer. DOE proposes to assign testing responsibilities to the manufacturers of the envelope and refrigeration system.

• Envelope manufacturer would be responsible for testing the envelope according to the envelope test procedure.
• Refrigeration system manufacturer would be responsible for testing the refrigeration system according to the refrigeration system test procedure.
• Purpose of this provision:

– Accurately reflect the structure of the walk - in market.

– Assign testing responsibilities to the appropriate equipment manufacturers.19 | Building Technologies Program eere.energy.gov 

### Background & Approach

Issue 1 - 1 : Separate Test Procedures for Envelope & Refrigeration System DOE invites comments on its proposal for separate test procedures for the insulated envelopes and refrigeration systems of walk - in coolers and freezers. See Section III.C. 1 . for details.
Issue 1 - 2: Testing Responsibilities DOE invites comments on its proposal to consider the envelope and refrigeration manufacturers responsible for the envelope and refrigeration system test, respectively.

20 | Building Technologies Program eere.energy.gov 

### DOE proposes that the definition of “envelope” include the box, its components, and some electrical equipment. Background & Approach >> Envelope

Issue 1 - 3 : Definition of Envelope DOE invites comments on its proposed definition for the envelope of walk - in coolers and freezers. See Section III.B. 1 . for details. • ― Envelope means (1) the portion of a walk - in cooler or walk - in freezer that isolates the interior, refrigerated environment from the ambient, external environment; and (2) all energy- consuming components of the walk - in cooler or walk- in freezer that are not part of its refrigeration system.‖
• Examples: (1) insulated panels, windows, gasketing, doors (passage & display), etc. (2) lighting , anti - sweat door heaters, etc.21 | Building Technologies Program eere.energy.gov 

### In the NOPR, DOE proposed the following definition for “refrigeration system:” Background & Approach >> Refrigeration

― Refrigeration system means the mechanism used to create the refrigerated environment in the interior of a walk - in cooler or freezer, consisting of an integrated single package refrigeration unit, or a split system with separate unit cooler and condensing unit sections, or a unit cooler that is connected to a central rack system; and including all controls and other components integral to the operation of this mechanism.‖

22 | Building Technologies Program eere.energy.gov 

### DOE is interested in commenter feedback regarding the proposed definition of “refrigeration system.” Background & Approach >> Refrigeration

REVISED DEFINITION WOULD READ AS FOLLOWS: ― Refrigeration system means the mechanism used to create the refrigerated environment in the interior of a walk- in cooler or freezer, consisting of a packaged system where the unit cooler and condensing unit are integrated into a single piece of equipment, or a split system with separate unit cooler and condensing unit sections, or a unit cooler that is connected to a multiplex condensing system ; and including all controls and other components integral to the operation of this mechanism.‖ 

### Revisions to the definition may include the following:
• Substituting ―integrated single package refrigeration unit,‖ with ― a packaged system where the unit cooler and condensing unit are integrated into a single piece of equipment

‖ in order to clarify the term.

• Substituting ―central rack system,‖ with ― multiplex condensing system,‖ because the latter is a more inclusive term and may be more technically accurate .23 | Building Technologies Program eere.energy.gov Issue 1 - 4: Definition of “Refrigeration System” DOE invites comments on the proposed definition for the refrigeration system of walk- in coolers and freezers, and the suggested modifications to the proposed definition. DOE seeks comment on other possible modifications to the definition to help improve its clarity. See Section III.C.1 for details. 

### Background & Approach >> Refrigeration

24 | Building Technologies Program eere.energy.gov 

### Table of Contents Overview of Public Meeting

1 Background & Approach 2 Proposed Test Procedure – Envelope 4 Proposed Test Procedure – Refrigeration System 5 Impacts on Small Businesses 6 Others Issues/Closing Discussion 7 Basic Model 325 | Building Technologies Program eere.energy.gov 

###  In the NOPR, DOE proposed using this approach for both the

envelope and the refrigeration system. DOE is considering allowing manufacturers to group similar walkin equipment under a single “Basic Model.” Basic Model >> Concepts & Definitions

• Under this proposal, DOE is considering:

– Allowing manufacturers to group equipment with essentially identical characteristics with regard to energy consumption under a single Basic Model.

– For envelopes, this approach would include adopting a calculation methodology for determining the energy consumption of units within the Basic Model.

• The purpose of using Basic Models is to reduce testing burden . The proposed Basic Model approach enables manufacturers to group equipment with respect to energy consumption characteristics and test only one unit within a Basic Model.

26 | Building Technologies Program eere.energy.gov 

### Basic Model >> Concepts & Definitions



###  DOE believes this approach ensures compliance with a future

standard while reducing testing burden. The Basic Model concept provides a way for manufacturers to rate their equipment without testing every unit.

• Manufacturers must rate the energy consumption of every unit of walk- in equipment that they manufacture. • Manufacturers are required to test at least one unit of each Basic Model to determine its energy consumption. • For envelopes , the manufacturers may use a calculation methodology to rate every other unit in the Basic Model based on the test results from the tested unit.

– DOE proposes a calculation methodology for rating envelopes within a Basic Model because every envelope a manufacturer makes could be unique.27 | Building Technologies Program eere.energy.gov 

### The underlying rationale for the Basic Model is the Daily Energy Consumption Coefficient (DECC), a scaling factor that allows for 

### the calculation of energy consumption for some components. Basic Model >> Envelope

DECC Parameters Wall surface area Non - glass door surface area Glass display door surface area Glass wall and inset window surface area Opening of doors (and effectiveness of infiltration reduction devices) Electrical energy consumption due to devices including, but not limited to: lights, anti - sweat heaters, and motors to drive air mixing fans  DECCs provide a linear expression of the energy consumption of any

envelope of the same Basic Model as the tested envelope.

28 | Building Technologies Program eere.energy.gov 

###  DECCs are a scaling methodology that manufacturers would

use to rate their equipment. • In the standards framework document, DOE proposed to allow manufacturers to develop Alternative Efficiency Determination Methods (AEDMs) for calculating energy consumption of units.

– The AEDMs would be substantiated with test data and verified by DOE . 

### Basic Model >> Envelope 

### DOE developed the DECC to replace a previously proposed approach that stakeholder feedback indicated was not appropriate.

• Interested Parties (Standards Framework Public Meeting) objected to the idea of allowing manufacturers to develop AEDMs for these reasons:

– Could be expensive and time - consuming for manufacturers to develop.

– Could benefit some manufacturers unfairly .

– May not provide consistent information to end users.
• Therefore, DOE created a single, consistent calculation methodology based on Daily Energy Consumption Coefficients (DECCs).29 | Building Technologies Program eere.energy.gov Feature Sample change How addressed? New Rating? New Basic Model? Temperature Cooler vs. Freezer Testing Yes Yes Insulation Material • Foam (e.g., urethane, styrene) • Blowing agent (e.g., HFC 245fa) Infiltration Devices Strip or air curtains Assembly System • Panel locking system (e.g., camlock) • Gasketing, door sweep • Material Doors Materials
• Number of doors • Door type Calculation Yes No Dimensions of Envelope Size of envelope Electrical Load • Anti - sweat heaters • Lighting — interior, door Miscellaneous • Paint color, type • Type of metal (e.g., galvanized) • Shelving No action required No No 

### Basic Model >> Envelope 

### Which changes necessitate a separate Basic Model?

30 | Building Technologies Program eere.energy.gov 

###  Different Basic Models would be required because a trigger parameter is met. These WICF belong to different Basic Models. Basic Model >> Envelope

Different Basic Models? Rationale

Yes  Different insulation material 

### Polyurethane Polystyrene31 | Building Technologies Program eere.energy.gov 

###  However, these models would be RATED differently using DECCs, owing to their dimensional differences. These WICF belong to the same Basic Model.

Different Basic Models? Rationale

No  Same temperature  Same materials  Same assembly systems Cooler 

### Basic Model >> Envelope
Cooler

32 | Building Technologies Program eere.energy.gov 

### Example calculation for this Basic Model: the two units differ only in their surface area.

DECC = Energy Load / Exterior Surface Area Surface Area Basic Model Unit = 400 ft 2 Energy Load Basic Model Unit ( as tested ) = 5,126 Watt - hours (Wh) / day THEREFORE, the DECC Basic Model = 

### 12.815 Wh / day-ft 2 

### Basic Model >> Envelope33 | Building Technologies Program eere.energy.gov 

### Example calculation for this Basic Model: the units differ only in their surface area. Basic Model >> Envelope

DECC Basic Model = 12.815 Wh / day-ft 2 (from previous slide) Exterior Surface Area Calculated Unit = 1,200 ft 2 Energy Load Calculated Unit = DECC Basic Model X Exterior Surface Area Calculated Unit THEREFORE, the calculated Energy Load Calculated Unit = 

### 15.4 kWh / day

34 | Building Technologies Program eere.energy.gov 

### Taking these ideas into consideration, DOE proposes the following definition of Basic Model for envelopes: ―Basic Model means all units of a given type of walk - in equipment manufactured by a single manufacturer, and —with respect to envelopes, which do not have any differing construction methods, materials, components, or other characteristics that significantly affect the energy consumption characteristics.‖ Issue 2 - 1: Basic Model of Envelope DOE invites comments on the approach of grouping walk - in envelopes into Basic Models and on the proposed definition of Basic Model for envelopes. Issue 2 - 2: Daily Energy Consumption Coefficients DOE invites comments on the approach of using DECCs to calculate energy consumption of units with a Basic Model. 

### Basic Model >> Envelope35 | Building Technologies Program eere.energy.gov 

### Basic Model >> Refrigeration System



###  DOE is considering applying the Basic Model concept to refrigeration systems to reduce testing burden. The Basic Model concept could also apply to refrigeration systems.

• Refrigeration systems may be virtually identical but may have different design characteristics, either electrical (e.g. voltage), or physical (e.g. exterior finish), that would change the energy consumption either very minimally or not at all .

• The purpose of using a Basic Model would be reducing the testing burden on manufacturers by allowing them to group similar models of refrigeration systems into a single Basic Model.

36 | Building Technologies Program eere.energy.gov 

### Basic Model >> Refrigeration System



###  DOE is considering an additional approach to the Basic Model definition and concept originally described in the NOPR. DOE is considering the following options for testing refrigeration systems: Option Description Implications 1 Basic Model approach proposed

in the NOPR • Manufacturers may group several models into a single Basic Model, consisting of units that may differ in energy consumption but not significantly . • It may be difficult to determine what constitutes a ―significant‖ difference. 2 Basic Model approach used for

other equipment in the appliance standards program • Manufacturers may group several models into a single Basic Model, consisting of models that do not differ in energy consumption. • Purely cosmetic changes, e.g. those to the exterior finish, would not necessitate a new test. 3 No provision for Basic Model • Manufacturers must test one of every model of refrigeration system they manufacture37 | Building Technologies Program eere.energy.gov 

### Basic Model >> Refrigeration System



###  In this approach, differences that impact energy consumption in a minimal way would not trigger a new Basic Model. DOE is considering how best to define the term Basic Model for refrigeration systems, if a Basic Model were used for this 

### equipment.

• As defined in the NOPR, refrigeration systems in one Basic Model could include design changes that do affect energy consumption , though minimally. ( Option 1 on the previous slide)

• Original definition proposed in NOPR that DOE is considering: ―Basic Model means all units of a given type of walk - in equipment manufactured by a single manufacturer, and —With respect to refrigeration systems, which do not have any differing electrical, physical, or functional characteristics that significantly affect energy consumption.‖

38 | Building Technologies Program eere.energy.gov



###  In this approach, any difference that impacts energy consumption in any way would trigger a new Basic Model. DOE is considering how best to define the term Basic Model for refrigeration systems, if a Basic Model were used for this equipment. Basic Model >> Refrigeration System



### • DOE is considering a revised definition : refrigeration systems in one Basic Model could not include design changes that affect energy consumption. ( Option 2 )



### • Revised definition that DOE is considering: ―Basic Model means all units of a given type of walk - in equipment manufactured by a single manufacturer, and —With respect to refrigeration systems, which have electrical characteristics that are essentially identical, and which do not have any differing electrical, physical, or functional characteristics that affect energy consumption.‖39 | Building Technologies Program eere.energy.gov 

### Basic Model >> Refrigeration System 

### DOE may decide to reject both Option 1 and Option 2, leaving the default of no provision for Basic Model (Option 3).

• DOE may decide that manufacturers cannot use either Basic Model approach. • In this case, manufacturers would have to test one of every model of refrigeration system they manufacture. • This would ensure that every model would be rated accurately and could be certified to comply with a future energy conservation standard.

40 | Building Technologies Program eere.energy.gov Issue 2 - 3: Basic Model of Refrigeration Systems DOE invites comments on these options and whether a Basic Model approach is necessary or appropriate for refrigeration systems. DOE asks interested parties to suggest additional options that DOE should consider.
Issue 2 - 4: Definition of Basic Model for Refrigeration Systems DOE invites comments on the definitions of Basic Model as proposed in the NOPR and as outlined in this presentation. For purposes of defining Basic Model, DOE also requests comment on what might constitute a ―significant difference‖ in energy consumption that would make a new Basic Model necessary. 

### Basic Model >> Refrigeration System41 | Building Technologies Program eere.energy.gov 

### Table of Contents Overview of Public Meeting

1 Background & Approach 2 Basic Model 3 Proposed Test Procedure – Refrigeration System 5 Impacts on Small Businesses 6 Others Issues/Closing Discussion 7 Proposed Test Procedure – Envelope 4

42 | Building Technologies Program eere.energy.gov 

### Envelope energy load depends on a variety of components. Envelope >> Overview

Doors

Lights Heater Wire Metal Skin & Insulated Panels43 | Building Technologies Program eere.energy.gov 

### Conduction, infiltration, and electric use determine envelope energy load. Envelope >> Overview

Conduction Load Surfaces (Non - glass) Foam Insulation Surfaces

( Glass) Glass Systems Infiltration Load Doors Electrical Load &

Electrical Heat Load

Performance Test Envelope Test Procedure Steadystate infiltration Infiltration

Reduction Devices Energy Use of WICF Envelope

Envelope Electrical Devices

44 | Building Technologies Program eere.energy.gov 

### Envelope >> Overview

 As in this example for glass doors, various components may impact energy load through more than one of the three primary mechanisms. 

### The purpose of the envelope test procedure is to accurately and fully capture the energy load of the envelope.

Conduction Load Infiltration Load Electrical Load & Electrical Heat Load Energy Load of WICF Envelope

Glass Door Heater Wire45 | Building Technologies Program eere.energy.gov 

###  Energy associated with the envelope will be normalized by

external surface area (ft 2 

### ) Stakeholder comments suggested that WICF should be normalized by a parameter related to the size of the walk- in. Envelope >> Overview > Normalization
WICF Normalization Factor: External Area and Glass Area Ratio

• DOE believes that the external surface area of the envelope is an appropriate normalization factor

– Surface area is the key geometric characteristic related to both conduction and infiltration

– Glass surface area in particular has a major impact on energy use. • Therefore, DOE proposes to normalize the energy use by an external surface area corrected by the ratio of glass to non - glass area of the WICF.

46 | Building Technologies Program eere.energy.gov 

### Equation 3 - 34 describes the energy normalization and correction by surface area and glass to non - glass ratio, respectively. Envelope >> Overview > Normalization

Issue 3 - 1: Normalization Factor DOE invites comments on its proposal to normalize the energy consumption using surface area. See Section III.B.3.e for details.

Eq. 3 - 34 E = Energy (kWh/day-ft2 ) A = Area (ft 2 ) Q = Heat load (kWh/day)47 | Building Technologies Program eere.energy.gov 

### Conduction refers to the transfer of heat through a material and is a key mechanism of heat gain. Envelope >> Conduction

Conduction Load Surfaces (Non - glass) Foam Insulation Surfaces

(Glass) Glass Door Systems Measured by R -value Infiltration Load Electrical Load & Electrical Heat Load

Performance Test Envelope Test Procedure

48 | Building Technologies Program eere.energy.gov 

### Envelope >> Conduction > Foam R - Value



###  Foam R - Value has a major impact on WICF conduction losses. “R-Value” is typically used to describe the performance of a thermally insulating material. 

## R -Value, ft 2 

## - F - h/Btu

• R - Value is a measure of resistance to thermal conductivity . • The greater the R - Value, the greater the thermal resistance.
• Foam is the most common insulating material used in walk - in cooler and freezer construction. @ 4” thickness • Steel R - Value: 0.16 ft 2 - F - h/Btu

• Foam R - Value: 16.00 - 32.00 ft 2 - F - h/Btu • Vacuum Insulated Panel R -value: 120 - 200 ft 2 - F - h/Btu49 | Building Technologies Program eere.energy.gov 

### Envelope >> Conduction > Foam R - Value 

### Heat transfer through insulation is easily calculated. The calculation requires known area, R -value, thickness, and ΔT.



## T2 

## ( ̊ F) T 1



### ( ̊ F) h (ft)



### w (ft)

t (in) 

## R (ft2

## - F - hr/Btu)

50 | Building Technologies Program eere.energy.gov 

### Envelope >> Conduction > Foam R - Value



###  There are two key mechanisms of R -value decline: the diffusion

of gases and moisture infiltration. At the framework public meeting, DOE received numerous comments regarding the diminishing R - Value of insulating foams. 1. Diffusion of gases , which typically occurs within 2 - 3 years after manufacture. 2. Moisture infiltration , which may occur over time due to environmental conditions inherent in refrigerated boxes and WICF design, such as but not limited to differences in temperature and relative humidity.51 | Building Technologies Program eere.energy.gov 

### DOE found that diffusion and water absorption may affect the R value of foam insulation. Envelope >> Conduction > Foam R - Value

Conduction Load Surfaces ( Non - glass) Foam Insulation Surfaces

(Glass) Glass Door Systems Measured by R - Value Infiltration Load

Issue: Diffusion Issue: Water Absorption Electrical Load & Electrical Heat Load

Performance Test Envelope Test Procedure

52 | Building Technologies Program eere.energy.gov 

###  Although the cells are called “closed,” they are permeable. The insulating performance of foam depends both on the plastic polymer and on the gas trapped within its cells.

Foam Insulation Closed Cells Filled with blowing agent 

### WICF Panel Foam Cells 

### Envelope >> Conduction > Foam R - Value53 | Building Technologies Program eere.energy.gov 

###  The rate of diffusion of gases decays exponentially. Initially, foam cells are filled with high concentration of blowing agent. Over time, the concentration of blowing agent decreases. Envelope >> Conduction > Foam R - Value

Primary mechanism 1. Air (nitrogen and oxygen) diffuses into the cells. 2. The air reduces the concentration of blowing agent and therefore reduces the thermal resistivity of the foam. Secondary mechanism 1. Blowing agent diffuses out of the foam into the atmosphere. 2. This further reduces the concentration of blowing agent and reduces thermal resistivity.

= Air = Blowing Agent Individual Cell

54 | Building Technologies Program eere.energy.gov 

###  The change in concentration of blowing agent over time

reduces insulating performance. First, air diffuses into the foam cells, and then the blowing agent diffuses out of the foam. Envelope >> Conduction > Foam R - Value

Primary Diffusion Secondary Diffusion After manufacture = Air = Blowing Agent55 | Building Technologies Program eere.energy.gov 

### DOE believes that thin slicing is the best option for conditioning insulating foams. Envelope >> Conduction > Foam R - Value

Overview of ASTM C1303 - 08 test procedure 1. Slice the full thickness foam sample. 2. Allow time to pass (time determined based on slice thickness). 3. Measure the R - Value of the stack of slices using ASTM C518 - 04. Benefits
• Results from thin slicing are used to predict an average R - value over a 15 year life.
• The U.S. building industry recognizes that initial R - values decline over time and therefore uses conditioned R - values on labeling of insulating foams.
• Since 2001, Canada has required industries using insulating foams to use a thin slicing method to accelerate conditioning.

56 | Building Technologies Program eere.energy.gov Issue 3 - 2 : Proposed Test Method for Conditioning of Foam DOE invites comment on the proposal to require the use of ASTM C 1303 - 08 , ―Standard Test Method for Predicting Long - Term Thermal Resistance of Closed - Cell Foam Insulation,‖ as a standard conditioning method for insulating foams used in walk in coolers and freezers prior to testing these foams with ASTM C 518 - 04 as required by EPCA. See Section III.B. 2 .a. for details. 

### Envelope >> Conduction > Foam R - Value57 | Building Technologies Program eere.energy.gov Conduction Load Surfaces (Non - glass) Foam Insulation Surfaces

(Glass) Glass Door Systems Measured by R - Value Infiltration Load

Issue: Diffusion Issue: Water Absorption 

### Oral and written comments submitted by interested parties requested that DOE investigate the impact of water absorption on 

### the R -Value of foams. Envelope >> Conduction > Foam R - Value

Electrical Load & Electrical Heat Load

Performance Test Envelope Test Procedure

58 | Building Technologies Program eere.energy.gov 

### DOE believes that water impacts the R - Value of foam insulation. No test procedure is currently available and DOE has not developed one. Envelope >> Conduction > Foam R - Value



## Summary of Water Issues 1. There are limited or nonexistent industry - accepted measurement procedures for this issue. 2. Limited research conducted by academic, government, or industry has focused on issues specific to the building industry rather than WICF.59 | Building Technologies Program eere.energy.gov Issue 3 - 3 : Impact of Water on Foam DOE invites comments on this issue . See Section III.B. 2 .ii for details. 

### Envelope >> Conduction > Foam R - Value

60 | Building Technologies Program eere.energy.gov Conduction Load Surfaces (Non - glass) Foam Insulation Surfaces

(Glass) Glass Door Systems Measured by R - Value Infiltration Load

Issue: Diffusion Issue: Water Absorption 

### Oral and written comments submitted by interested parties regarding diffusion and water absorption referenced the topic of permeability of “skins”. Envelope >> Conduction > Foam R - Value

Electrical Load & Electrical Heat Load

Performance Test Envelope Test Procedure Issue: Skins61 | Building Technologies Program eere.energy.gov 

### Many manufacturers seek to prevent or delay diffusion and moisture infiltration. Envelope >> Conduction > Foam R - Value

DOE received conflicting comments on this issue 1. Whether WICF walls can be made fully impermeable using metal skins;

- OR 2. Whether full impermeability cannot be achieved due to: • Lack of or imperfect sealing at panel joints; • Imperfect adherence of foam to metal skins during or after manufacture; and/or • Deliberate punctures for fixtures and shelving and/or inadvertent punctures that typically occur in the field.

62 | Building Technologies Program eere.energy.gov Issue 3 - 4: Efficacy of Skins DOE invites comments on skins used to reduce moisture and air permeance through insulating materials. DOE invites the submission of test results regarding the impact of impermeable skins on long - term R - value , specifically peer - reviewed, published data pertaining to the efficacy of skins in preventing or delaying R - value decline. See Section III.B.2.a for details. 

### Envelope >> Conduction > Foam R - Value63 | Building Technologies Program eere.energy.gov 

###  The proposed correction is available on the following slide. DOE is considering a correction to the method used to calculate heat transfer through floorless coolers. Envelope >> Conduction > Floor

Floorless Coolers: Correction to NOPR

• In the published NOPR, DOE proposed the use of a method for calculating heat transfer through uninsulated cooler floors . • Subsequent modeling has demonstrated that the previously published approach could be improved.

64 | Building Technologies Program eere.energy.gov 

### DOE is considering an improved approach to calculating the heat transfer ONLY through floorless coolers. Envelope >> Conduction > Floor

Floorless Coolers: Proposed Correction

• DOE performed computational simulations of walk - in coolers of various sizes. • The result is an equation that is a function of floor area. • A = floor area of the walk - in cooler [ft 2 

### ] • q floor

### = Average floor heat flux [Btu/h - ft 2 

### ] If A ≤ 750 ft2 , q floor = 33.153 x A- 0.364 If A > 750 ft 2 , q floor = 0.0002 x A + 2.8465 | Building Technologies Program eere.energy.gov 

### Comparison of original and new equations from the published NOPR: Envelope >> Conduction > Floor Original Eq. 3 - 10 (except floorless coolers)

New Eq. 3 - 10a (for floorless coolers only)

Issue 3 - 5: Floorless Cooler Heat Transfer DOE invites comment on its proposed correction for floorless coolers.

66 | Building Technologies Program eere.energy.gov 

### DOE is considering conditional requirements for heat transfer calculations through insulated freezer floors. Envelope >> Conduction > Floor

Issue 3 - 6: Freezer Floor R - Values DOE invites comment on freezer floor R - values. See Section III.B.3.b for details. Freezers: R - 28 Floor Assumption If the manufacturer does not provide any additional insulating surface:

• DOE will require the use of an R - value of 28 [ft 2 - F - h/Btu] for freezers for the purposes of calculating the energy loss through walk - in freezer floors. • This reflects the R - value minimum prescribed by EPCA for freezer floors.67 | Building Technologies Program eere.energy.gov 

### DOE proposes a correction to the floor temperature assumption for insulated floors in WICF. Envelope >> Conduction > Floor

Floor Surface Temperature Assumption
• In the NOPR, DOE specified that 55 ̊ F be used in heat transfer calculations for both freezers and coolers.

• DOE proposes replacing 55 ̊ F with separate assumptions: 1. Freezers: 60 ̊ F 2. Coolers: 65 ̊ F
Issue 3 - 7 : Insulated Floor Surface Temperature Assumptions DOE invites comment on floor surface temperature assumptions.

68 | Building Technologies Program eere.energy.gov 

### Conduction refers to the transfer of heat through a material and is a key mechanism of heat gain. Envelope >> Conduction > Glass U - Factor

Conduction Load Surfaces (Non - glass) Foam Insulation Surfaces

(Glass) Glass Door Systems Measured

by U - Factor Infiltration Load Electrical Load & Electrical Heat Load

Performance Test Envelope Test Procedure69 | Building Technologies Program eere.energy.gov 

### In addition to panes, the inert gas fill, emissivity coating, and pane separation distance have an impact on door performance. Envelope >> Conduction > Glass U - Factor

Variables That Impact U - Factor

Include:

• Number of glass panes • Glass coatings • Inert gas fill • Inter - pane spacing • Frame materials • Gasket materials Gas Fill

Pane Spacing Glass Pane Frame Coatings


### WICF cooler R-Value Walls = 20 -30 [ft2 - F - h/Btu] Glass Doors = 2 -3 [ft2 - F h/Btu] U - Factor = 1 / R-Value

70 | Building Technologies Program eere.energy.gov



###  Manufacturers may use Window 5.2 method only if an NFRC label is not available. DOE proposes that manufacturers account for the energy use of their glass components with the NFRC component label. Envelope >> Conduction > Glass U - Factor

Primary Option: National Fenestration Rating Council (NFRC) Label If WICF door suppliers participate in the NFRC rating program, the performance of the door shall be simply read from its label and used for calculations in this test procedure. Alternative Option: Window 5.2 Calculation If a glass door does not have an NFRC rating, then DOE proposes to require manufacturers to use Lawrence Berkeley National Laboratory‘s (LBNL) publicly available Window 5.2 software package to calculate glass door performance.71 | Building Technologies Program eere.energy.gov 

### LBNL’s Window 5.2 software (available for free online) has been thoroughly verified with years of use and empirical test data. Envelope >> Conduction > Glass U - Factor
Use of Window 5.2 Software

• The WICF manufacturer must fully document the glass door model and all specifications/inputs used calculate the U - Factor in Window 5.2 such as the size of the door, number of panes of glass, gas fill between panes, pane spacing etc.

• This will help ensure that inputs used to calculate overall door performance are not being manipulated since any of the results should be reproducible and inputs can be directly compared to shipped products. Issue 3 - 8 : Performance Data of Glass Products DOE seeks comment on the availability of performance data on glass products used in walk- in applications, glass component manufacturers‘ participation in third - party certification programs such as NFRC, and the proposed method for predicting the thermal performance of glass components using Window 5 . 2 .

72 | Building Technologies Program eere.energy.gov 

### NOPR Clarification: energy calculation for display-type WICF sold with and without glass doors Envelope >> Conduction > Glass U - Factor Display-Type Walk- in Sold Without Display Doors For the purposes of calculating the energy use associated with display doors:

- EPCA maximum whole door U - Factors : 0 .43* and 0.3* [Btu/hr-ft 2 - F] for coolers and freezers, respectively 

### Display -Type Walk- in Sold With Display Doors For the purposes of calculating the energy use associated with display doors:

- The rating of the glass doors sold with the walk- in shall be used.

Issue 3 - 9 : Glass Door Energy Calculation DOE seeks comment on the use of using EPCA maximum U - Factor for glass door energy calculations and their related assumed values. *Calculated using Window 5.2: 2 - pane argon gas fill and 3 - pane argon gas fill for coolers and freezers (no low e - coatings).73 | Building Technologies Program eere.energy.gov 

### Infiltration refers to air leakage into WICF and is a key pathway for envelope energy losses. Envelope >> Infiltration > Steady - State

Infiltration Test Doors Steadystate Infiltration Infiltration

Reduction Devices Envelope Infiltration Load Electrical Load & Electrical Heat Load Conduction Load

Performance Test Envelope Test Procedure

74 | Building Technologies Program eere.energy.gov 

###  Air exchange accounts for a large portion of WICF energy use. DOE proposes to account for steady- state air infiltration in the envelope test procedure. Envelope >> Infiltration > Steady - State

Door Threshold Panels Panel -to - Panel Interface Pressure Relief Valve Steady- state infiltration may occur through:

- Panels

- Panel - to - panel interfaces

- Door threshold

- Bi - directional pressure relief valves (freezers)75 | Building Technologies Program eere.energy.gov 

### DOE identified the Gas Tracer Method as a good method for measuring air infiltration in WICF. Envelope >> Infiltration > Steady - State 

### WICF Envelope Step 1 Step 2 

### = Tracer Gas Step 3 Step 4 Time = 0

Time > 0 1. Inject tracer gas 2. Measure gas concentration 3. Let time pass (air exchange occurs) 4. Measure gas concentration 5. Calculate infiltration rate (change in concentration over time )

76 | Building Technologies Program eere.energy.gov 

### DOE proposes the use of ASTM E741 - 06 to measure steady- state infiltration and the effectiveness of infiltration reduction devices. Envelope >> Infiltration > Steady - State

Issue 3 - 10 : Steady- State Infiltration Measurement DOE invites comments on the proposed test method for measuring steady- state infiltration. See Section III.B. 2 .b for details on the proposed analytical methods. • ASTM E 741 - 06 : ―Standard Test Method for Determining Air Change in a Single Zone by Means of a Tracer Gas Dilution‖ • Also referred to as the Gas T racer Method

• The Gas Tracer Method is NOT used for calculation of air infiltration related to door- opening events. (An analytical approach is used instead to calculate air exchange due to door opening events).77 | Building Technologies Program eere.energy.gov 

### Infiltration refers to air leakage into WICF and is a key pathway for envelope energy losses. Envelope >> Infiltration > Door Opening

Door Opening Events (calculation) Doors Steadystate infiltration Infiltration

Reduction Devices Envelope Infiltration Load Electrical Load & Electrical Heat Load Conduction Load

Performance Test Envelope Test Procedure

78 | Building Technologies Program eere.energy.gov 

### Envelope >> Infiltration > Door Opening



###  Door opening air exchange accounts for a large portion of WICF energy use. Hot air enters through the top of the passage as cold dense air flows through the bottom.

Open Door 

### Cold Air



## Hot, Humid Air
Factors that impact energy lost during air infiltration : 1. Door size 2. Air properties (relative humidity and temperature) 3. Door opening frequency 4. Door opening duration 5. Infiltration reduction device effectiveness WICF Side View WICF Front View

The energy associated with door infiltration is calculated using ASHRAE defined equations (as described in the NOPR).79 | Building Technologies Program eere.energy.gov 

### DOE proposes the use of an analytical method to calculate infiltration due to door - opening events. Envelope >> Infiltration > Door Opening

Issue 3 - 11 : Calculations for Door- Opening Events DOE invites input and feedback on the calculations proposed for determining infiltration from door - opening events. See Section III.B. 2 .b for details on the proposed analytical methods. • The DOE approach uses equations described in ASHRAE Fundamentals as well as assumed door - opening frequency, duration, and the measured infiltration barrier effectiveness to calculate the air infiltration associated with each door.
• This method avoids the burden of individual infiltration measurements for each unique door.

80 | Building Technologies Program eere.energy.gov 

### Infiltration refers to air leakage into WICF and is a key pathway for envelope energy losses. Envelope >> Infiltration > Door Opening

Reduction Effectiveness Test Doors Steadystate infiltration Infiltration

Reduction Devices Envelope Infiltration Load Electrical Load & Electrical Heat Load Conduction Load81 | Building Technologies Program eere.energy.gov 

###  IRD performance is measured in terms of device effectiveness. Infiltration Reduction Devices (IRD) can reduce air exchange associated with door opening events. Envelope >> Infiltration > Door Opening



### Strip Curtain IRDs include:

- Strip Curtains

- Air Curtains

- Automated curtain doors
Source: DOE 

### Air Curtain

82 | Building Technologies Program eere.energy.gov 

### Infiltration Reduction Device effectiveness is measured using the gas tracer test. Envelope >> Infiltration > Door Opening



### With IRD

1. Measure Infiltration Open Doorway WICF Front View 

### Without IRD

2. Measure Infiltration Device Effectiveness =

Issue 3 - 12: Infiltration Reduction Device Effectiveness DOE invites input and feedback on the IRD effectiveness test. See section III.B.2.b.iii for details. IRD Open Doorway Infiltration w/ IRD Infiltration w/o IRD 

## 1 - Correction to

NOPR83 | Building Technologies Program eere.energy.gov 

### Electricity use is another form of energy consumption in the envelope. Electricity is used for devices like heater wires and 

### lighting. Envelope >> Electrical

Infiltration Load Electrical Load & Electrical Heat Load Conduction Load Electrical Devices
Percent Time Off and name plate capacity (calculation)

84 | Building Technologies Program eere.energy.gov



###  This will provide a uniform means of comparison. DOE examined the energy use of electrical components sited within the envelope. Envelope >> Electrical

Electrical Device Calculations

• DOE recommends calculating the electricity consumption of lights, sensors, and other miscellaneous electrical devices not considered part of the refrigeration equipment using name - plate rating and an assumed daily operation . • DOE incorporates assumed duty cycles of lights, anti - sweat heaters, and other devices based on whether they are controlled by a preset control system .85 | Building Technologies Program eere.energy.gov 

### DOE assumed certain values for the daily operation of electrical components. Envelope >> Electrical
Percent Time Off (PTO) Assumptions Lights • PTO value of 25% for systems without timers or other

auto shut - off systems. • PTO value of 50% for systems with timers or other auto shut - off systems installed. Anti - sweat heaters • PTO value of 0% for all systems without direct or

indirect relative humidity sensing controls. • DOE further proposes that 75% be used for walk- in coolers and 50% for walk- in freezers with these controls.

86 | Building Technologies Program eere.energy.gov 

### DOE assumed certain values for the daily operation of electrical components. Envelope >> Electrical
Percent Time Off (PTO) Assumptions Powered infiltration reduction devices • For devices not actively controlled based on door open or closed positions, DOE proposes a PTO value of 25%. • For devices actively controlled based on door open or closed position for display doors , DOE proposes 99.33%. • For devices actively controlled based on door open or closed position for all other doors , DOE proposes 99.17%. All other devices • DOE proposes a PTO value of 0% , unless the walk - in manufacturer can demonstrate that the device is controlled by a preset control system. • If this can be demonstrated, DOE proposes 25% for the device in question.87 | Building Technologies Program eere.energy.gov 

### Envelope >> Electrical

Issue 3 - 13: Percent Time Off ( PTO) Assumptions DOE invites comments on the assumed PTO for the purposes of calculating electrical load of the envelope. See Section III.B.3.d for details.

88 | Building Technologies Program eere.energy.gov 

###  All electrical devices sited inside a WICF increase the amount of heat that must be removed by the refrigeration equipment. DOE examined the energy impact of door anti - sweat heaters and lights (power use and heat generation). Glass Door with Anti -sweat Heating Envelope >> Electrical 

## WICF89 | Building Technologies Program eere.energy.gov 

### Evaluating the conduction, infiltration, and energy consumption of electrical devices yields values of heat gain. Envelope >> Electrical



###  A means for translating the thermal properties of the envelope into a quantifiable energy consumption value is needed. 

## Energy Consumption Associated with the Envelope

• A single metric, in units of kWh/day, is preferred . • The heat gains related to the envelope are expressed in units of [Btu/h].

- For these reasons, a method is needed to express these thermal gain values into heat removed by the refrigeration system [i.e. convert Btu/h to kWh/day]

90 | Building Technologies Program eere.energy.gov 

### DOE proposes the use of Energy Efficiency Ratios (EER) to “convert” the envelope - related thermal energy into kWh/day of electrical energy consumption. Envelope >> EER

• EERs represent the relative system efficiencies of walk - in refrigeration equipment; i.e. a measure of how many units of heat are removed per unit electrical energy input into the refrigeration equipment. • Proposed nominal values : DOE is considering the use of an EER of 12.4 and 6.3 (Btu/W- h) for coolers and freezers, respectively (AHRI 1250 - 2009 ).
Issue 3 - 14 : Nominal Energy Efficiency Ratio DOE invites comments on the use of EERs for the refrigeration system to determine the energy consumption associated with heat gain through the envelope due to conduction, infiltration and electric devices. See Section III.B. 3 .a for details.91 | Building Technologies Program eere.energy.gov 

### In summary, conduction, infiltration, and electric use determine envelope energy load. Envelope >> Overview

Conduction Load Surfaces (Non - glass) Foam Insulation Surfaces

(Glass) Glass Systems Infiltration Load Doors Electrical Load &

Electrical Heat Load

Performance Test Envelope Test Procedure Steadystate infiltration Infiltration

Reduction Devices Energy Use of WICF Envelope

Envelope Electrical Devices

92 | Building Technologies Program eere.energy.gov 

### Table of Contents Overview of Public Meeting

1 Background & Approach 2 Basic Model 3 Proposed Test Procedure – Envelope 4 Impacts on Small Businesses 6 Others Issues/Closing Discussion 7 Proposed Test Procedure – Refrigeration System 593 | Building Technologies Program eere.energy.gov 

### DOE proposes to adopt Air - Conditioning, Heating and Refrigeration Institute (AHRI) Standard 1250, published in 2009. Refrigeration >> Overview

• In 2009 , AHRI developed a new rating method for refrigeration systems of walk - in coolers and freezers . • DOE proposes to incorporate AHRI 1250 as the DOE test procedure for walk - in refrigeration systems.

– This test procedure measures Annual Walk in Energy Factor (AWEF), a measure of efficiency.

– DOE proposes to add calculations to derive the energy consumption as required by EPCA.

94 | Building Technologies Program eere.energy.gov 

### A refrigeration system consists primarily of a compressor, condenser, unit cooler and other miscellaneous components. Refrigeration >> Overview

Unit Cooler 

### Condenser Compressor Expansion valve Fan95 | Building Technologies Program eere.energy.gov 

### Refrigeration systems come in three general configurations: Refrigeration >> Overview
1. Packaged System 2. Split System 3. Unit Cooler Connected to a Multiplex System

Unit Cooler Unit Cooler Unit Cooler Compressor & Condenser Compressor & Condenser These systems have a dedicated compressor and condenser. The compressor and condenser are included in the test. This system does not have a dedicated compressor and condenser. The multiplex system is not included in the test.

Multiplex System

96 | Building Technologies Program eere.energy.gov 

### AHRI 1250 accounts for three different types of equipment systems. Refrigeration >> AHRI 1250



###  The following slides summarize the tests for each system type. 1. Matched system : Unit cooler paired with a condensing unit and tested together as a complete system. 2. Mix- match system : Unit cooler and condensing unit are tested separately; their efficiency when they are paired together is calculated from the test results. 3. Unit cooler paired with a multiplex system : Unit cooler is tested alone. The efficiency is calculated using a nominal EER value for the multiplex system that depends on the suction dew point temperature.97 | Building Technologies Program eere.energy.gov 

### Summary of tests for a matched system. 

## Matched System On - cycle Steady State System Test On - cycle power consumption Net refrigeration capacity Off - cycle Evaporator Fan Power Test Off - cycle evap. fan power consumption Mandatory Defrost Test (freezer only) Energy input for defrost cycle Duration of defrost cycle Optional Defrost Test (freezer only) Time interval between defrosts 

### Refrigeration >> AHRI 1250



## Mix- Match System Unit Cooler (paired with multiplex system)

98 | Building Technologies Program eere.energy.gov 

### Summary of tests for a mix - match system. Refrigeration >> AHRI 1250



## Mix- Match System Unit Cooler Test Capacity test at 2 different suction temperatures Net Refrigeration Capacity Off - cycle Evaporator Fan Power Test Off - cycle Evap. Fan

Power Consumption Mandatory Defrost Test (freezer only) Energy Input for Defrost Cycle Duration of Defrost Cycle Optional Defrost Test (freezer only) Time Interval Between Defrosts 

### Condensing Unit Test On - cycle test On - cycle Power Consumption Gross Refrigeration Capacity 

## Matched System

Unit Cooler (paired with multiplex system)99 | Building Technologies Program eere.energy.gov 

### Summary of tests for a unit cooler paired with a multiplex system. Refrigeration >> AHRI 1250



## Unit Cooler (paired with multiplex system) 

### Unit Cooler Test Capacity Test Net Refrigeration Capacity Off - cycle Evaporator Fan Power Test Off - cycle Evap. Fan Power Consumption Mandatory Defrost Test (freezer only) Energy Input For Defrost Cycle Duration Of Defrost Cycle Optional Defrost Test (freezer only) Time Interval Between Defrosts 

## Mix- Match System Matched System

100 | Building Technologies Program eere.energy.gov 

### The test procedure specifies test conditions for various parameters to give credit for energy- saving technologies. Refrigeration >> AHRI 1250

Category Parameter Conditions Interior WICF Temperature Cooler At 35 F Freezer At - 10 F Condenser Location Indoors At one ambient temperature (90 F) Outdoors At three ambient temperatures (35 F,

59 F, and 95 F) Compressor Type Fixed - capacity At single capacity Two - capacity At both capacities Variable - capacity At minimum, maximum, and an intermediate capacity101 | Building Technologies Program eere.energy.gov 

### DOE examined AHRI 1250 and believes that the methods are well suited to test WICF refrigeration systems. Refrigeration >> AHRI 1250

• Based on test methods already used in the industry and shown to be accurate and repeatable . • Developed and approved by industry and published by the industry trade association.
• Applicable to the covered equipment because it accounts for the unique operating conditions, configurations, and use patterns of WICF refrigeration.
• Gives credit for energy saving technologies such as variable - speed evaporator fans and defrost control strategies.
Issue 4 - 1: Proposed Test Procedure DOE invites comment on whether AHRI 1250 - 2009 is an appropriate test procedure for refrigeration systems used in walk - ins . See Section III.C.1 for details.

102 | Building Technologies Program eere.energy.gov 

### A fter t h e test d ata are gat h ered, t h e A W E F is ca lculated . Ref ri g e rati o n >> Cal c u l ati o n

• T he A W E F is a m ea sure ofth e efficien cy of th e syste m . • T he ref r ige rat ion syste m is an alytically pa ired with a th eo ret ical en v elo pe . • T he te st proce du re calcu late s th e en ergy th e ref r ige rat ion syste m wou ld use to reje ct th e he at loa d asso ciate d with th e en v elo pe .

* D o e s n ot i n cl u d e h e at g e n e rat e d by t h e ref ri g e rat i o n syst e m .103 | Building Technologies Program eere.energy.gov 

###  The assumed ambient conditions are consistent across all

WICF refrigeration systems. The test procedure calculates the AWEF under assumed ambient conditions. Refrigeration >> Calculation

Assumptions Regarding Ambient Conditions: 1. For indoor units, the ambient temperature is assumed to be constant at 90 ° F. 2. For outdoor units, the ambient temperature varies according to an assumed temperature profile . The Ambient Conditions Affect: 1. The conduction load on the theoretical envelope, which contributes to the total heat load removed from the walk- in. 2. The energy consumption of the condensing unit.

104 | Building Technologies Program eere.energy.gov 

### DOE adapted the AHRI test procedure to fulfill the statutory requirement of EPCA. Refrigeration >> Calculation

• The AHRI test procedure calculates the AWEF of a refrigeration system, a measure of efficiency .

* Does not include heat generated by the refrigeration system.

• The DOE test procedure derives annual energy use from the AWEF, consistent with the EPCA mandate that the test procedure measure ―energy use.‖

* Does not include heat generated by the refrigeration system.105 | Building Technologies Program eere.energy.gov 

### DOE derived energy use from measured data and constants. Refrigeration >> Calculation
Temperature profile data (outdoor only) (tj) Heat load for each ambient temperature

Total annual heat load that must be removed by the refrigeration system 

### Total annual



### energy use AWEF Net refrigeration capacity at test temp (qss) [Btu/h] 

### Measured data and constants Hourly temp. profile data (outdoor only) (nj)



### Result

106 | Building Technologies Program eere.energy.gov 

### DOE proposes the following equations in the rule language: Refrigeration >> Calculation

Legend: q ss = net capacity AWEF = annual walkin energy factor t j = temperature j n j = number of hours at temperature j Indoor units Coolers: Freezers: Outdoor units Coolers:
Freezers: Net heat removed

Net heat removed107 | Building Technologies Program eere.energy.gov 

### The method DOE used to derive these equations appears in the NOPR. Refrigeration >> Calculation

Issue 4 - 2: Calculation Methodology DOE invites comments on its proposed method for deriving annual energy consumption from the AWEF. See Section III.C.4 for details.

108 | Building Technologies Program eere.energy.gov 

### DOE anticipates that manufacturers would measure and report both the annual energy consumption and the AWEF. Refrigeration >> Reporting Requirements

Issue 4 - 3: Reporting Requirements DOE requests comments on the approach of reporting both energy consumption and AWEF. See Section III.C.4 for details. • DOE does not specify certification and reporting requirements in this test procedure . • DOE will develop future certification requirements in another rulemaking.
• DOE expects that the test procedure will be used to measure compliance with a future energy conservation standard.
• Either AWEF or energy consumption could be more useful in developing an energy conservation standard.109 | Building Technologies Program eere.energy.gov 

### Table of Contents Overview of Public Meeting

1 Background & Approach 2 Basic Model 3 Proposed Test Procedure – Envelope 4 Proposed Test Procedure – Refrigeration System 5 Others Issues/Closing Discussion 7 Impacts on Small Businesses 6

110 | Building Technologies Program eere.energy.gov 

### DOE must consider impacts on small businesses. Small Business Impacts

• SBA size standard for the commercial and industrial refrigeration manufacturing industry: < 750 employees . • Sources that list businesses in the WICF industry include:

– Regulatory databases

– AHRI‘s listing of commercial refrigeration manufacturer members

– National Sanitation Foundation (NSF) Section 7 database
• DOE found 37 small manufacturers of WICF envelopes and 5 small manufacturers of WICF refrigeration systems . • There could be other small manufacturers than are publicly listed.
Issue 5 - 1: Number of Small Entities Regulated DOE invites comments on the number of small entities that may be affected by the proposed rule. See Section IV.B.3 for details.111 | Building Technologies Program eere.energy.gov 

### DOE identified potential impacts and burden - reducing measures for walk- in equipment. Small Business Impacts

• Impacts are associated with the cost of testing and length of time it takes to perform the tests.
• Measures that may reduce burdens include:

– Allowing low- cost testing options; e.g., for ASTM E 741 - 06 , DOE specifies CO 2 as the tracer gas, the lowest - cost option.

– Reducing the number of tests manufacturers need to perform by allowing them to group similar models into one Basic Model.
• These apply to all manufacturers but may have a greater impact on small business manufacturers. Issue 5 - 2: Impacts on Small Manufacturers DOE invites comments on the expected impact of the rule on small entities and whether that impact is expected to be significant. DOE also asks whether small manufacturers would be differentially impacted by the proposed test procedures. DOE requests comments on any alternatives to the proposed rule and their impacts on small manufacturers. See Section IV.B for details.

112 | Building Technologies Program eere.energy.gov 

### Table of Contents Overview of Public Meeting

1 Background & Approach 2 Basic Model 3 Proposed Test Procedure – Envelope 4 Proposed Test Procedure – Refrigeration System 5 Impacts on Small Businesses 6 Others Issues/Closing Discussion 7113 | Building Technologies Program eere.energy.gov 

### Closing Remarks



### Interested parties who wish to make a closing statement should speak now.

114 | Building Technologies Program eere.energy.gov



###  Comment period is open until March 31, 2010 How to submit comments: Closing Remarks >> Comments Public Meeting – Oral comments will be captured in the transcript and become part of the public record. Written Comments – Reference Docket EERE -2008 -TP - 0014 and/or RIN 1904 -AB85 . Email: WICF - tp - 2008 - 0014@ee.doe.gov

Include EERE - 2008 - BT-TP - 0014 and/or RIN 1904 - AB85 in the subject line of your message. Mail: Brenda Edwards

U.S. Department of Energy Building Technologies Program 1000 Independence Avenue, SW Mailstop EE - 2J Washington, DC 20585 - 0121 Courier: Brenda Edwards

U.S. Department of Energy Building Technologies Program 950 L‘Enfant Plaza, 6 th Floor Washington, DC 20024 Telephone: 202 - 586 - 2945 

### Please include one signed original paper copy.