### CHAPTER 5. ENGINEERING ANALYSIS

TABLE OF CONTENTS

5.1 INTRODUCTION

............................................................................................................. 5-1

5.2 METHODOLOGY OVERVIEW

...................................................................................... 5-1

5.3 COST MODEL

.................................................................................................................. 5 -2

5.3.1 Cost Model Overview

............................................................................................. 5-2

5.3.2 Structure of the Cost Model Spreadsheet

................................................................ 5-4

5.3.2.1 Material Prices

......................................................................................... 5-4

5.3.2.2 Fabricated Parts and Purchased Parts

...................................................... 5-4

5.3.2.3 Factory Parameters

................................................................................... 5-7

5.3.3 Downstream An alyses

............................................................................................ 5-9

5.3.4 Manufacturer Selling Price Estimates

..................................................................... 5-9

5.4 ENERGY CONSUMPTION MODEL

............................................................................ 5-10

5.4.1 Screened-In Technologies

..................................................................................... 5-10

5.4.1.1 Screened in Technologies for Envelopes

............................................... 5-10

5.4.1.2 Screened in Technologies for Refrigeration Systems

............................ 5-11

5.4.2 Screened-In Technologies Not Considered in the Engineering Analysis

............. 5-11

5.4.2.1 Ambient Subcooling

.............................................................................. 5-11

5.4.2.2 High Efficiency Two-speed and Variable-speed Compressors

............. 5-12

5.4.3 Design Options

...................................................................................................... 5-12

5.4.4 Details for Envelope Design Options

................................................................... 5-16

5.4.4.1 Improved Wall, Ceiling, and Floor Insulation

....................................... 5-18

5.4.4.2 Improved Door Gaskets and Pa nel Interface Systems

........................... 5-23

5.4.4.3 Electronic Lighting Ballasts and High-Efficiency Lighting

.................. 5-25

5.4.4.4 Occupancy Sensors and Au tomatic Door Opening and Closing Systems. 5­

27

5.4.4.5 Air Curtains and Strip Curtains

.............................................................. 5-27

5.4.4.6 Vestibule Entryways

.............................................................................. 5-29

5.4.4.7 Display and Window Glass System Insulation Enhancement

............... 5-30

5.4.4.8 Anti-sweat Heater Controls and No Anti-sweat Systems

...................... 5-32

5.4.5 Details for Refrigeration Sy stem Design Options

................................................ 5-33

5.4.5.1 High-Efficiency Scroll Compressors

..................................................... 5-34

5.4.5.2 Condenser Coil

....................................................................................... 5-35

5.4.5.3 Condenser Fan Motors

........................................................................... 5-36

5.4.5.4 Evaporator and Condens er Fan Blades

.................................................. 5-36

5.4.5.5 Evaporator Coil

...................................................................................... 5-37

5.4.5.6 Evaporator Fan Control

.......................................................................... 5-38

5.4.5.7 Floating Head Pressure

.......................................................................... 5-39

5.4.5.8 Defrost Controls

..................................................................................... 5-39

5.4.6 Baseline Specifications

......................................................................................... 5-40

5.4.7 Non-Numerical Assumptions

................................................................................ 5-45

5.4.7.1 Assumptions Concerning the Envel ope Energy Calculations

............... 5-45

5.4.7.2 Assumptions Concerning the Refrigeration Energy Consumption

........ 5-46

5.4.8 Numerical Constants and Assumptions

................................................................ 5-47

5-i

### 5.4.9 Model Components: Envelope

.............................................................................. 5-49

5.4.9.1 Heat Conduction Load

........................................................................... 5-50

5.4.9.2 Energy Efficiency Ratio (EER)

............................................................. 5-50

5.4.9.3 Infiltration Load: Steady-State

............................................................... 5-51

5.4.9.4 Infiltration Load: Door Opening

............................................................ 5-51

5.4.9.5 Anti-Sweat and Other Heater Wire Electrical Load

.............................. 5-51

5.4.9.6 Lighting Electrical Load

........................................................................ 5-52

5.4.9.7 Other Electrical Devices

........................................................................ 5-52

5.4.9.8 Additional Heat Load Due to Elect rical Device Waste Heat

................. 5-52

5.4.10Model Components: Refrigeration

....................................................................... 5-52

5.4.10.1 Net Capacity

........................................................................................... 5-54

5.4.10.2 On-Cycle System Power

........................................................................ 5-54

5.4.10.3 Load Factors

........................................................................................... 5-54

5.5 COST-EFFICIENCY CURVES

...................................................................................... 5-56

5.5.1 Envelope Cost-Effici ency Curves

......................................................................... 5-57

5.5.2 Refrigeration Cost-Effi ciency Cu rves

................................................................... 5-69

LIST OF TABLES

Table 5.3.1 Cost Model Output Classifications

.......................................................................... 5-2 Table 5.3.2 Purchased WICF Components

................................................................................. 5-6 Table 5.3.3 Factory Parameter Assumpti ons, Refrigeration Equipment

.................................... 5-8 Table 5.3.4 Factory Parameter Assumptions, Envelope

............................................................. 5-8 Table 5.4.1 Baseline Design Options for Envelope, Non-Display

........................................... 5-13 Table 5.4.2 Baseline Design Options for Envelope, Display

................................................... 5-14 Table 5.4.3 Baseline Design Options for Refrigeration Systems

............................................. 5-15 Table 5.4.4 Design Option Codes and Descriptions for Envelopes

.......................................... 5-17 Table 5.4.5 Details for “Wall and Ceiling In sulation Thickness” Design Option

.................... 5-18 Table 5.4.6 Details for “Wall and Ceiling Insula tion Thickness” Design Option Cont.

.......... 5-18 Table 5.4.7 Details for “Wall and Ceiling Insula tion Thickness” Design Option Cont.

.......... 5-19 Table 5.4.8 Total Shipping Cost for Product Classes and Thicknesses Considered

................. 5-19

Table 5.4.9 Details for “Floor Insulati on” Design Option, FEA Results

................................. 5-20

Table 5.4.10 Details for “Floor Insula tion” Design Option, FEA Inputs

................................. 5-20

Table 5.4.11 Details for “Floor Insu lation” Design Option, Cost

............................................ 5-21

Table 5.4.12 Details for “Insulation Materials A” Design Option

........................................... 5-21

Table 5.4.13 Details for “Insulation Materials B” Design Option

............................................ 5-22

Table 5.4.14 Details for “Insulation Materi als B” Design Option, Continued

......................... 5-22

Table 5.4.15 Details for “Insulation Materials B” Design Option, Engineering Cost

.............. 5-22

Table 5.4.16 Details for “Insulation Materials B” Labor Cost

................................................. 5-23

Table 5.4.17 Details for “Sealant E nhancement” Design Option

............................................. 5-24

Table 5.4.18 Details for “Sealant Enhan cement” Design Option, Cont.

.................................. 5-24

Table 5.4.19 Details for “Sealant Enhancement” Design Option, Engineering Cost

............... 5-25

Table 5.4.20 Details for “Sealant Enhancem ent” Design Option, Labor Cost

......................... 5-25

Table 5.4.21 Details for “Sealant Enhancemen t” Design Option, Material Cost

..................... 5-25 Table 5.4.22 Details for “Lighting: Display” Design Option, Performance Data

.................... 5-26 Table 5.4.23 Details for “Lighting: Display” Design Option, Performance Data Cont.

.......... 5-26

5-ii

### Table 5.4.24 Details for “Lighting: Display” Design Option, Cost Data

................................. 5-26 Table 5.4.25 Details for “Lighting: Display” Design Option, Cost Data Cont

........................ 5-26 Table 5.4.26 Details for “Lighting: Non-Display” Design Option

........................................... 5-27

Table 5.4.27 Details for “Control Systems” Design Option

..................................................... 5-27

Table 5.4.28 Details for “Active Infiltrati on Reduction Devices” Design Option

................... 5-28

Table 5.4.29 Details for “Passi ve Infiltration Reduction De vices” Design Option

.................. 5-29 Table 5.4.30 Details for “Door Sy stems” Design Option

......................................................... 5-30 Table 5.4.31 Details for “Display Door Enhancement” Design Option

................................... 5-31 Table 5.4.32 Details for “Display Door En hancement” Design Option, Window 5.2

............. 5-31 Table 5.4.33 Details for “Display Door Enha ncement” Design Option, Window 5.2, Coolers ......

............................................................................................................................. 5-31

............................................................................................................................. 5-32 Table 5.4.34 Details for “Display Door Enhanc ement” Design Option, Window 5.2, Freezers.....

Table 5.4.35 Details for “Display Door Enhanc ement” Design Option, Gas Fill Cost

............ 5-32

Table 5.4.36 Details for “Anti-Sweat Heaters” Design Option

................................................ 5-33 Table 5.4.37 Design Option Codes and Descri ptions for Refrigeration Systems

..................... 5-34 Table 5.4.38 Details for "High-Efficiency Scroll Compressor" Design Option

....................... 5-35

Table 5.4.39 Details for "Condenser Coil" Design Option

....................................................... 5-35

Table 5.4.40 Details for "Condenser Co il" Design Option, Continued

.................................... 5-36

Table 5.4.41 Details for "Condenser Fan Motor" Design Option

............................................. 5-36 Table 5.4.42 Details for “High Efficiency Fan Blades – Evaporator” Design Option

............. 5-37 Table 5.4.43 Details for “High Efficiency Fa n Blades – Condenser” Design Option

.............. 5-37 Table 5.4.44 Details for "Evapora tor Coil" Design Option

...................................................... 5-38 Table 5.4.45 Details for "Evaporator Coil" Design Option, Continued

................................... 5-38 Table 5.4.46 Details for “Evaporator Fan Control” Design Option

......................................... 5-39 Table 5.4.47 Details for “Floating He ad Pressure” Design Option

.......................................... 5-39

Table 5.4.48 Details for “Defrost Controls” Design Option

..................................................... 5-40 Table 5.4.49 Baseline Specifications for Envelopes, Coolers

.................................................. 5-41 Table 5.4.50 Baseline Specifications for Envelopes, Freezers

................................................. 5-42 Table 5.4.51 Baseline Specifications for Refrige ration Systems, Medium Temperature

......... 5-43 Table 5.4.52 Baseline Specifications for Refri geration Systems, Low Temperature

............... 5-44 Table 5.4.53 Envelope Assumptions

........................................................................................ 5-4 8 Table 5.4.54 Refrigeration System Assumpti ons Associated with Defrost

.............................. 5-49 Table 5.4.55 Refrigeration System Baseline TD Assumptions

................................................ 5-49 Table 5.5.1 Cost-Efficiency Data for th e ND.C. Small Equipment Class

................................ 5-57 Table 5.5.2 Cost-Efficiency Data for th e ND.C. Medium Equipment Class

............................ 5-58 Table 5.5.3 Cost-Efficiency Data for th e ND.C. Large Equipment Class

................................ 5-59 Table 5.5.4 Cost-Efficiency Data for th e D.C. Small Equipment Class

................................... 5-60 Table 5.5.5 Cost-Efficiency Data for th e D.C. Medium Equipment Class

............................... 5-61 Table 5.5.6 Cost-Efficiency Data for th e D.C. Large Equipment Class

................................... 5-62 Table 5.5.7 Cost-Efficiency Data for th e ND.F. Small Equipment Class

................................ 5-63 Table 5.5.8 Cost-Efficiency Data for th e ND.F. Medium Equipment Class

............................ 5-64 Table 5.5.9 Cost-Efficiency Data for th e ND.F. Large Equipment Class

................................ 5-65 Table 5.5.10 Cost-Efficiency Data for the D.F. Small Equipment Class

................................. 5-66 Table 5.5.11 Cost-Efficiency Data for th e D.F. Medium Equipment Class

............................. 5-67 Table 5.5.12 Cost-Efficiency Data for th e D.F. Large Equipment Class

................................. 5-68

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### Table 5.5.13 Cost-Efficiency Data for the DC.M.I Equipment Class (Small)

......................... 5-69 Table 5.5.14 Cost-Efficiency Data for the DC.M.I Equipment Class (Large)

......................... 5-70 Table 5.5.15 Cost-Efficiency Data for the DC.M.O Equipment Class (Small)

........................ 5-71 Table 5.5.16 Cost-Efficiency Data for the DC.M.O Equipment Class (Large)

........................ 5-72 Table 5.5.17 Cost-Efficiency Data for the MC.M.I Equipment Class (Small)

......................... 5-73 Table 5.5.18 Cost-Efficiency Data for the MC.M.I Equipment Class (Large)

......................... 5-74 Table 5.5.19 Cost-Efficiency Data for the DC.L.I Equipment Class (Small)

.......................... 5-75 Table 5.5.20 Cost-Efficiency Data for the DC.L.I Equipment Class (Large)

.......................... 5-76 Table 5.5.21 Cost-Efficiency Data for the DC.L.O Equipment Class (Small)

......................... 5-77 Table 5.5.22 Cost-Efficiency Data for the DC.L.O Equipment Class (Large)

......................... 5-78 Table 5.5.23 Cost-Efficiency Data for the MC.L.I Equipment Class (Small)

.......................... 5-79 Table 5.5.24 Cost-Efficiency Data for the MC.L.I Equipment Class (Large)

.......................... 5-80

LIST OF FIGURES

Figure 5.3.1 Production Flow in BOM

....................................................................................... 5-3 Figure 5.3.2 Components of Ma nufacturer Sellin g Price

......................................................... 5-10 Figure 5.4.1 Panel Tongue a nd Groove Construction

............................................................... 5-23 Figure 5.4.2 Overhead View of Walk-In and Vestibule Entryway

........................................... 5-30 Figure 5.4.3 Examples of Standard Fan Blades,

....................................................................... 5-37 Figure 5.4.4 Examples of High Efficiency Fan Blades,

........................................................... 5-37 Figure 5.4.5 Overview of Envelope Engi neering Analysis Calculations

................................. 5-50 Figure 5.4.6 Energy Consumption Model for Dedicated Condensing Systems

....................... 5-53 Figure 5.4.7 Energy Consumption Model for Un it Coolers Connected to Multiplex Condensing Systems

................................................................................................................ 5-56 Figure 5.5.1 Cost-Efficiency Curve for the ND.C. Equipment Class [Small, Number of Doors: Display, Passage, and Freight (0,1,0)]

................................................................. 5-57 Figure 5.5.2 Cost-Efficiency Curve for the ND.C. Equipment Class [Medium, Number of Doors: Display, Passage, and Freight (0,1,1)]

................................................................. 5-58 Figure 5.5.3 Cost-Efficiency Curve for the ND.C. Equipment Class [Large, Number of Doors: Display, Passage, and Freight (0,2,1)]

................................................................. 5-59 Figure 5.5.4 Cost-Efficiency Curve for the D.C. Equipment Class [Small, Number of Doors: Display, Passage, and Freight (3,1,0)]

................................................................. 5-60 Figure 5.5.5 Cost-Efficiency Curve for the D.C. Equipment Class [Medium, Number of Doors: Display, Passage, and Freight (8,1,0)]

................................................................. 5-61 Figure 5.5.6 Cost-Efficiency Curve for the D.C. Equipment Class [Large, Number of Doors: Display, Passage, and Freight (50,2,0)]

............................................................... 5-62 Figure 5.5.7 Cost-Efficiency Curve for the ND.F. Equipment Class [Small, Number of Doors: Display, Passage, and Freight (0,1,0)]

................................................................. 5-63 Figure 5.5.8 Cost-Efficiency Curve for the ND.F. Equipment Class [Medium, Number of Doors: Display, Passage, and Freight (0,1,1)]

................................................................. 5-64 Figure 5.5.9 Cost-Efficiency Curve for the ND.F. Equipment Class [Large, Number of Doors: Display, Passage, and Freight (0,2,1)]

................................................................. 5-65 Figure 5.5.10 Cost-Efficiency Curve for the D.F. Equipment Class [Small, Number of Doors: Display, Passage, and Freight (3,1,0)]

................................................................. 5-66

5-iv

### Figure 5.5.11 Cost-Efficiency Curve for the D.F. Equipment Class [Medium, Number of Doors: Display, Passage, and Freight (8,1,0)]

................................................................. 5-67 Figure 5.5.12 Cost-Efficiency Curve for the D.F. Equipment Class [Large, Number of Doors: Display, Passage, and Freight (50,2,0)]

............................................................... 5-68 Figure 5.5.13 Cost-Efficiency Curve for th e DC.M.I Equipment Class (Small)

...................... 5-69 Figure 5.5.14 Cost-Efficiency Curve for the DC.M.I Equipment Class (Large)

...................... 5-70 Figure 5.5.15 Cost-Efficiency Curve for th e DC.M.O Equipment Class (Small)

.................... 5-71 Figure 5.5.16 Cost-Efficiency Curve for the DC.M.O Equipment Class (Large)

.................... 5-72 Figure 5.5.17 Cost-Efficiency Curve for th e MC.M.I Equipment Class (Small)

..................... 5-73 Figure 5.5.18 Cost-Efficiency Curve for the MC.M.I Equipment Class (Large)

..................... 5-74 Figure 5.5.19 Cost-Efficiency Curve for the DC.L.I Equipment Class (Small)

....................... 5-75 Figure 5.5.20 Cost-Efficiency Curve for the DC.L.I Equipment Class (Large)

....................... 5-76 Figure 5.5.21 Cost-Efficiency Curve for th e DC.L.O Equipment Class (Small)

..................... 5-77 Figure 5.5.22 Cost-Efficiency Curve for the DC.L.O Equipment Class (Large)

..................... 5-78 Figure 5.5.23 Cost-Efficiency Curve for the MC.L.I Equipment Class (Small)

...................... 5-79 Figure 5.5.24 Cost-Efficiency Curve for the MC.L.I Equipment Class (Large)

...................... 5-80

5-v

### CHAPTER 5. ENGINEERING ANALYSIS

5.1 INTRODUCTION The engineering analysis establishes the relationship between manufacturer selling price (MSP) and energy consumption for the walk-in co olers and freezers covere d in this rulemaking. The cost-energy consumption relationship serves as the basis for the cost/benefit calculations for individual customers, manufacturer s, and the Nation. In determining this relationship, the U.S. Department of Energy (DOE) estimates the increase in manufacturer production cost (MPC) associated with technological changes that redu ce the energy consumption of baseline models, then converts each MPC to MSP by applying a multiplier to determine th e manufacturer markup.

The primary inputs to the engineering analys is are baseline information and data for each equipment class addressed in the market and technology assessment (chapter 3 in the preliminary TSD) and technology options from the screening analysis (chapter 4 in the preliminary TSD). Additional inputs include cost and energy consum ption data that DOE estimated using a cost model and an energy consumption model, respec tively. The primary output of the engineering analysis is a set of cost-energy consumption curves and a manufacturer markup multiplier used to convert MPC to MSP. In the subsequent mark ups analysis (chapter 6 in the preliminary TSD), DOE determines customer prices by applying distribution markups, sale s tax, and contractor markups. After applying these markups, the data serve as inputs to the energy use analysis (chapter 7 in the preliminary TSD) and the life cycle cost and payback period analyses (chapter 8 in the preliminary TSD).

In this chapter, DOE discusses represen tative baseline units, methodology used to develop MPC, markups to MSP, sensitivity to material prices , methodology used to estimate energy consumption, cost-energy consumption curves, normalization of energy consumption metrics, and design options.

5.2 METHODOLOGY OVERVIEW This section describes the analytical methodol ogy used in the engineering analysis. In this rulemaking, DOE is adopting a design-opti on approach, which calculates the incremental costs of adding specific design options to a baseline model. As discussed in Chapter 2, DOE is considering the envelope and the refrigeration sy stem separately. Conse quently, DOE developed separate engineering curves for envelopes and re frigeration systems while using the same general cost and energy consumption models for each component. Furthermore, fo r each equipment class of both envelopes and refrigera tion systems, DOE analyzed different size equipment to assess how energy use varies with size. DOE specified a small- and large-capacity unit of each class for the refrigeration system analysis, and a small, medi um, and large size envelope of each class for the envelope analysis. A baseline unit was specified for each equipment class based on equipment offerings currently on the market. See chapter 3 of the preliminary TSD for a detailed description of the equipment classes and section 5.4.6 below for a dditional detail on the different size machines analyzed.

5-1

### For each equipment class and size, DOE developed both an envelope cost and a refrigeration system cost using a manufacturing cost model. DOE also developed an envelope energy consumption and a refrigeration system energy consumption using an energy consumption model. DOE combined the cost an alyses and energy consumption analyses to obtain a relationship between cost and energy consumption, expre ssed as a plot of cost vs. energy consumption for each design option, for re frigeration systems and envelopes. These plots appear in section 5.5.

5.3 COST MODEL

The cost model is the first of two key an alytical models used in constructing costefficiency curves. A cost model was used to estimate the baseline cost of an envelope and a refrigeration system of a walk-in cooler or freez er. This cost model was adapted from the cost models for beverage vending machines and comm ercial refrigeration equi pment, as walk-ins share many of the same genera l components and features. The cost model was significantly modified to add features that are unique to walk -in envelopes and refrigeration systems, such as foam insulation and large fan assemblies. DOE al so modified the model for walk-in coolers and freezers using input from stakeholders on un it MPC estimates and assu mptions to confirm

accuracy.

The cost model is based on pr oduction activities and divides factory costs into the following categories:

Table 5.3.1 Cost Model Output Classifications
Major Category Sub-Category Description

Material Costs Direct Raw materials (i.e. coils of sheet me tal) and purchased parts (i.e. fan motors, compressors, etc.)

Indirect Welding rods, die oil, release media

Manufacturing

Labor Assembly Parts / unit assembly on manufacturing line

Fabrication Conversion of raw material into parts ready for assembly

Indirect Fraction of overall labor not associated directly with product manufacturing, i.e. forklift drivers, quality control, for example. Supervisory Fraction of above labor, is paid a higher wage

Depreciation Equipment, Conveyor, Building Straight line depreciation over expected life.

Tooling Cost is allocated on a per-use basis or obsolescence, whichever is

shorter.

Other Overhead Utilities A fixed fraction of all material costs meant to cover electricity and other utility costs.

Maintenance Based on installed equipment and tooling investment. Property Tax and

Insurance A fixed fraction based on total unit costs.



### The cost model analysis created cost es timates for each of the walk-in coolers and freezers analyzed. The cost model uses specific assumptions to provide cost estimates, and the following sections describe these assumptions.

5.3.1 Cost Model Overview

5-2

### This section provides a genera l overview of how the cost model works. The first step in the cost model analysis is to create a structured bill of materials (BOM) as a basis for all future cost analysis. Typically, products or equipment are purchased and disassembled piece-by-piece until no parts are left over. Every component is cataloged, analyzed, and photographed. Items are classified by sub-assembly, function, and any fabrication and assembly operations that DOE estimates the manufacturer to perform in their facility. For example, DOE distinguishes whether parts are purchased (and hence are limited to assembly) or whether the components are fabricated on site (requiring equipment, labor, etc. prior to integration into the final product). DOE consults a wide range of industry sources for purchased parts and raw materials to help

estimate total material costs. A dditionally, DOE conducts site vis its to confirm which parts are purchased versus being fabricated on-site, and why.

Purchased Parts Inventory Fabrication

Processes Assembly, Packaging,

Distribution Raw
Materials Read y -to- A ssemble

Parts



### Figure 5.3.1 Production Flow in BOM

For the WICF analysis, DOE did not conduct a tea r-down analysis based on equipment available for purchase due to the size and complexity of purchasing entire walk-in cooler systems. Instead, DOE visited multiple manufacturing facilities to observe variability in manufacturing techniques, noting materials, purchased parts, and labor used. Add itionally, DOE conducted interviews with manufacturers to ensure the accuracy of the WICF model’s methodology and pricing.

When appropriate, a supplem entary method, called a catalogue teardown, was used to supplement the already-gathered data. A catalo gue teardown is based on published manufacturer product literature and supplementa ry component data. Typically, it uses a similar product that was torn down as a starting point, and differences in construction, purchased parts, etc. are then accounted for. A catalog teardown thus serves the purpose of greatly expanding the number of units and capacity ranges under consideration w ithout the significant expense attached to purchasing a very wide range of equipment.

Besides noting all material, labor, and overhead costs, the cost model also estimates the facility requirements for a given production volum e. Thus, the bill of materials (BOM) will generate detailed equipment, t ooling, and space requirements for a given production volume. For this rulemaking, incoming and outgoing freight were accounted for since they have a significant impact on production and shipping costs due to the large physical volume of WICF panels. However, the outbound freight cost is not considered a manufacturing cost, but is added as part of the manufacturer selling price. DOE based assu mptions about the sourcing of parts and inhouse fabrication on industry experience, informati on in trade publications, and discussions with

manufacturers.

5-3

### In sum, DOE assigned costs of labor, materials, and overhead to each part, whether purchased or produced in-house. DOE then aggreg ated single-part costs into major assemblies (e.g., panel assembly, door a ssemblies, condensing unit, evap orator unit, controls, and packaging), and summarized these costs in a spreadsheet.

5.3.2 Structure of the Cost Model Spreadsheet

Manufacturer practices and cost structure play an important role in estimating the final cost of the equipment. Depending on conditions in the marketplace regarding capital, labor, and other factors, a manufacturer will choose differ ent approaches to manufacturing its products, ranging from outsourcing all production to being co mpletely vertically in tegrated. DOE attempts to capture a representative view of industry ec onomic and manufacturing conditions through its model, teardowns, and site visits.

For this particular industry, DOE noted that manufacturers generally assembled panel systems with a mix of raw materi als (i.e. converted sheet metal, foam, etc.) and purchased parts (i.e. fasteners, door hardware, cut-to-length se als, etc.). WICF refrigeration systems were generally purchased either as complete assemblie s or modified in-house using purchased parts. For the raw materials being converted to ready-to-assemble parts, DOE estimated manufacturing process parameters, e.g., manufacturing equipment use and time for each item, the required initial material quantity, scrap, etc. to determine the value of each component. All parameters related to manufacture and assembly are then aggregated to determine facility requirements at various manufacturing scales and the final unit cost.

The final equipment cost includes the mate rial, labor, depreciation, and overhead costs associated with the manufacturing facility. The material costs include both raw materials and purchased part costs. The labor costs include fabrication, assembly, and indirect and overhead (burdened) labor rates. The de preciation costs include manufac turing equipment depreciation, tooling depreciation, and buildin g depreciation. The overhead cost s include indirect process costs, utilities, equipment and building maintenance, and rework. The following sections describe the cost model assump tions related to material pri ces, purchased parts and factory

parameters.

5.3.2.1 Material Prices

DOE determined the cost of raw materi als on the basis of manufacturer feedback, American Metals Market, i 

### and Bureau of Labor Statistics Producer Price Index (PPI) data. ii 

### To help address the impact of significant metal price fluctuations, metal price data is averaged over a five-year period. For non-metal materials, such as plastics, DOE uses the most current material prices it can obtain as opposed to a five-year average.

5.3.2.2 Fabricated Parts and Purchased Parts

DOE characterized parts based on whether manufacturers fabricated them in-house or purchased them from outside suppliers. For fabricated parts, DOE estimated initial raw material dimensions to account for scrap. For scrap materi als that are recyclable, DOE assigned a scrap

credit that is a fraction of the base material cost (i.e. high-cost rifled copper tubing is recycled on

5-4

### the basis of the scrap value for plain copper). No n-recyclable materials incur a disposal cost for all scrap.

For purchased parts, DOE estimated the purchase price for OEMs based on discussions with manufacturers and suppliers, expected shipment volumes, and industry experience. Whenever possible, DOE obtained price quotes directly from supplie rs of the manufacturers for the units being analyzed. DOE assumed that th e components in Table 5.3.2 were purchased from outside suppliers.

5-5

### Table 5.3.2 Purchased WICF Components

Assembly Purchased Sub-Assemblies
Refrigeration Equipment Components

Condensing Unit Compressor

Condenser Fan Blade

Condenser Fan Motor

Condenser Coil
Filter/Dryer

Hi/Low Pressure Switch

Accumulator

Valves

Plastic Parts

Evaporating Unit Evaporator Fan Blade

Evaporator Fan Motor
Evaporator Coil

Defrost Heater Rods

Distribution Header

TXV/EEV/Orifice

Plastic Parts

Controls Control Boards
Capacitors, transformers, contactors, etc.
Envelope Components

Non-Display Door Assembly Hinges

Kick Plate
Door closing mechanism
Latch Assembly
Gasketing
Door Sweep

Camlocks
Temperature Gauge
Heater wire (for freezers only)
Heater accessories (for freezers only)

Display Door Assembly Pre-Assembled Unit (glazing, heater wire, light fixtures, hinges etc)

Panel Assembly Camlocks

Gaskets
Insulation (for board stock only)
Caulking for panel-to-floor interface



### As previously stated, variability in the co sts of purchased parts can account for large changes in the overall MPC values calculated. Purc hased part costs can vary significantly based on the quantities desired and the component suppliers chosen. The purchased part prices used in this study were typical values based on estimate d production volume and othe r factors. However, variability in these prices would exist in reality on a case-by-case basis.

5-6

### Due to the great diversity of manufacturing scale in the WICF industry, DOE estimates that the purchased parts costs in particular could vary significantly by manufacturer. Purchased parts make up roughly 60-70% of the MPC fo r refrigeration equipment and 20-30% of the envelope MPC. Additionally, so me parts like heat exchanger coils, control systems, and foam insulation may be produced in-house by some manu facturers and purchased by others, changing likely overall system costs and investment requirements. For the preliminary analysis, DOE determined an average for the MPC based on an estimated market share of 50 percent for manufacturers who purchase the coils and 50 perc ent for manufacturers who make the coil inhouse.

DOE also made several assumptions regard ing the purchase costs of control systems, including defrost control, fan motor control, a nd floating head pressure control. In surveying manufacturers and suppliers, DOE determined that the cost of these com ponents varies widely among manufacturers and suppliers. Often, several of these functions are packaged together into a single control system. Most manufacturers and suppliers apply a significant markup to these control systems – both single-function and multi-function – that can be many times that of the components used to make them; this markup acco unts for the labor and, more importantly, the expertise of the maker of these parts. The costs used in the engineering model reflect the price

DOE estimated that a manufacturer in the walk-in industry would pay to purchase the controls from a supplier; however, DOE recognizes that a walk-in manufacturer who makes these components in-house would not see the same cost, yet would be able to charge a premium on to the purchaser.

5.3.2.3 Factory Parameters

Certain factory parameters, such as fabricati on rates, labor rates, and wages also affect the cost of each unit produced. DOE factory parameter assumptions we re based on internal expertise and manufacturer feedback. Ta ble 5.3.3 and Table 5.3.4 below list the factory parameter assumptions used in the cost model.

5-7

### Table 5.3.3 Factory Parameter Assump tions, Refrigeration Equipment

Parameter Estimate Name-plate Production Capacity (units/year) 30,000 Actual Annual Production Volume (units/year) 12,000 Work Days Per Year (days) 250 Assembly Shifts Per Day (shifts) 2 Fabrication Shifts Per Day (shifts) 2.5 Fabrication Labor Wages ($/hr) 16 Assembly Labor Wages ($/hr) 16 Assembly Worker Hours Per Year 3,600

Fabrication Worker Hours Per Year 4,500 Length of Shift (hrs) 8 Units Per Day 48 Average Equipment Installation Cost (% of purchase price) 10% Fringe Benefits Ratio 50%

Indirect to Direct Labor Ratio 33% Average Scrap Credit (relative to base material cost) 30% Non-recyclable trash cost ($/lb) 0.01 Building Cost ($/ft 2 ) 100170

Worker Downtime 10% Building Life (in years) 3025 Burdened Assembly Labor Wage ($/hr) 24 Burdened Fabrication Labor Wage ($/hr) 24 Supervisor Span (workers/supervisor) 25 Supervisor Wage Premium (over fabrication and assembly wage) 30%



### Table 5.3.4 Factory Parameter Assumptions, Envelope

Parameter Estimate Name-plate Production Capacity (complete walk-ins/year) 30,000 Actual Annual Production Volume (complete walk-ins/year) 12,000 Work Days Per Year (days) 250 Assembly Shifts Per Day (shifts) 2 Fabrication Shifts Per Day (shifts) 2.5 Fabrication Labor Wages ($/hr) 16 Assembly Labor Wages ($/hr) 16 Assembly Worker Hours Per Year 3,600

Fabrication Worker Hours Per Year 4,500 Length of Shift (hrs) 8 Panels Per Day 48 Average Equipment Installation Cost (% of purchase price) 10% Fringe Benefits Ratio 50%

Indirect to Direct Labor Ratio 33% Average Scrap Credit (relative to base material cost) 30% Non-recyclable trash cost ($/lb) 0.01 Building Cost ($/ft 2 ) 170

Worker Downtime 10% Building Life (in years) 25 Burdened Assembly Labor Wage ($/hr) 24 Burdened Fabrication Labor Wage ($/hr) 24 Supervisor Span (workers/supervisor) 25 Supervisor Wage Premium (over fabrication and assembly wage) 30%

5-8

### 5.3.3 Downstream Analyses

The MSPs derived in the engineering analysis are inputs to the life-cycle cost analysis (LCC) and the manufacturer impact analysis (MIA). In the LCC, the MSPs are necessary to calculate the total installed cost of each unit. In the MIA, DOE constructs a number of scenarios that analyze how different pricing schemes imp act manufacturers financially. Hence, both the MSP and the direct production cost components of MSP are important drivers of results in the MIA. In chapters 8 and 12 of the preliminary TSD, respectively, DOE discusses how the engineering analysis results are used for those sections in greater detail.

5.3.4 Manufacturer Selling Price Estimates

At each stage of the distribution chain, manufacturers, wholesalers, and distributors apply a markup to cover their operating costs and prof it margins. In the engineering analysis, DOE determined a manufacturer markup, and applied this markup to the MPC to arrive at the MSP for each equipment class. Wholesaler , distributor, and other markups are determined in the markups analysis (see chapter 6 of the preliminary TSD).

The manufacturer markup is a market-share -weighted average value for the industry. DOE developed this markup by examining several WICF manufacturers’ gross margin information from annual reports and Securities and Exchange Commission 10-K reports. The manufacturers analyzed by DOE account for the majo rity of the WICF market, and some of these companies are subsidiaries of more diversifie d parent companies that manufacture equipment

other than walk-in coolers and freezers. Becaus e the 10-K reports do not provide gross margin information at the subsidiary level, the estimate d markups represent the average markups that the parent company applies over its entir e range of equipment offerings. DOE evaluated markups for 2004 through 2008, calculating the manufacturer markup as 100/(100 – average gross margin), where average gro ss margin is calculated as revenue – cost of goods sold. Taking this information into c onsideration, DOE is using an industry-wide manufacturer markup of 1.39 in the engineering analysis.

The cost of specific models

⎯ or cost to an individual ma nufacturer to produce walk-in cooler or freezer equipment

⎯ will vary depending on the equipment’s precise design and features, actual manufacturing processes, the equi pment mix in the factory, and other production factors. There are also considerable differences in the levels of vertical integration that affect cost structure and, hence the cost of equipment. Companies with a large market share and/or revenue base tend to be more vertically integrated than lower-volume competitors.

In order to calculate the most likely selling price, DOE researched the industry to determine the markups that manufacturers charge on top of the MPC. DOE determined that the average markup for the industry is 1.39. The MSP is a product of the MPC and the manufacturer markup, added to the outbound freight cost from the manufacturer to the distributor (freight from the distributor to other points in the distribution chain, including the end-user, is covered in downstream analyses. The components of MSP ar e shown in greater detail in Figure 5.3.2.The outbound freight cost is captured in the non-production cost under “other costs.”

5-9MSP

Full Cost of Production

Manufacturer Production Costs

Direct

Labor Direct

Material Overhead Depreciation Non-Production Costs Profit

EBIT Research & Development

Costs Other

Costs Selling, General, and

A dministrative

Costs



### Figure 5.3.2 Components of Manufacturer Selling Price

5.4 ENERGY CONSUMPTION MODEL

The energy consumption model is the second of two key analytical models used in constructing cost-efficiency curves. This model estimates the energy consumption of envelopes and refrigeration systems of walk-in coolers a nd freezers at various performance levels using a design-options approach. DOE developed the en ergy consumption model as a Microsoft Excel spreadsheet.

For a given equipment class, the model estimates the energy consumption for the baseline and the energy consumption of several levels of performance above the baseline. The model calculates energy consumption at each performance level separately. For the baseline level, DOE calculated a corresponding MPC using the cost mode l (described in section 5.3 above). For each level above the baseline, DOE used the cost increa ses of the various design options to recalculate

the MPC.

5.4.1 Screened-In Technologies

In the market and technology assessment (chapter 3 of the preliminary TSD), DOE defined an initial list of technolog ies that can be used to reduce the energy consumption of walkin coolers and freezers. DOE then anal yzed the following technology options:

5.4.1.1 Screened in Technologies for Envelopes

• Improved wall, ceiling, and floor insulation

• Improved door gaskets and panel interface systems

• Electronic lighting ballasts and high-efficiency lighting

• Occupancy sensors

• Automatic door opening and closing systems

• Air curtains

• Strip curtains

• Vestibule entryways

5-10

### • Display and window glass system insulation performance

• Anti-sweat heater controls

• No anti-sweat systems

5.4.1.2 Screened in Technologies for Refrigeration Systems

• Ambient subcooling

• High-efficiency compressors (including scroll, 2-speed, and variable speed)

• Condenser coil

• Condenser fan motors

• Condenser fan blades

• Evaporator coil

• Evaporator fan blades

• Evaporator fan control

• Floating head pressure

• Defrost controls

5.4.2 Screened-In Technologies Not Considered in the Engineering Analysis In the screening analysis (chapter 4 of the preliminary TSD), DOE narrowed this list by eliminating those technologies that can reduce annual energy consumption of walk-in coolers and freezers but do not reduce energy consumptio n as measured under the DOE test procedure. DOE then screened out those technologies that were not feasible, were not practical to manufacture, reduced equipment utility, or were considered unsafe.

The remaining list of screened-in technolog ies became an input to the engineering analysis. However, for reasons noted below, DOE did not incorporate all of these technologies in the energy consumption model. These include the following:

5.4.2.1 Ambient Subcooling

This process utilizes an oversized condenser or subcooling heat exchanger in order to further cool the condensed refrigerant. The resu lt is a decrease in coolant enthalpy and an increase in specific capacity, meaning that a lower mass flow rate of compressed refrigerant, and thus less compressor power, is needed. Ambient subcooling is only needed when head pressure has been reduced to the lowest allowable value; in any other case, it is more efficient to simply reduce the head pressure. This system then proves effective when the ambient temperature is low enough that the head pressure must be kept at a high level, as is often the case for systems operating in cooler geographical regions.

DOE intends to include floating head pressu re as a design option, as well as increasing

the size of the condenser. This will have a simila r effect to ambient subcooling, and as reducing the head pressure is more efficient, it was not necessary to implement ambient subcooling as a design option.

5-11

### 5.4.2.2 High Efficiency Two-speed and Variable-speed Compressors

Two- or multiple-capacity compressors presen t an opportunity for energy savings. These systems can take many forms, including single compressors with multiple stages or variable operating speeds as well as coupled sets of compre ssors which engage as necessitated by the load on the envelope. These technologies allow for th e compressor operating time and power to more closely follow the heat load, resulting in improved performance and decreased energy consumption. This would save energy as measur ed by the test procedure, in reducing cyclic losses of the system. However, DOE’s energy consumption model calculates the energy consumption analytically based on published data, and does not captu re these cyclic losses. Also, DOE was unable to find published energy use data for two-speed and variable-speed compressors, so was unable to analytically determine the energy savings. Thus, DOE did not consider this option in the engineering analysis, but will consider this option in a future stage of the rulemaking if data are available.

5.4.3 Design Options After conducting the screening analysis and re moving from consideration those technologies described above, the following te chnologies were implemented as design options in the energy consumption model:

Envelope:

• Improved Wall, ceiling, and floor insulation

• Improved Door gaskets and panel interface systems

• Electronic lighting ballasts and high-efficiency lighting

• Occupancy sensors and automatic door opening and closing systems

• Air curtains and strip curtains

• Vestibule entryways

• Display and window glass system insulation enhancement

• Anti-sweat heater controls and no anti-sweat systems

Refrigeration:

• High-efficiency compressors

• Improved condenser coil

• High-efficiency condenser fan motors

• Improved condenser fan blades

• Improved evaporator coil

• Improved evaporator fan blades

• Evaporator fan controls

• Floating head pressure

• Defrost controls

Table 5.4.1 through Table 5.4.3 show the baseline op tions for each equipment class for envelope and refrigeration, respectively. Sections 5.4.4.1 through 5.4.5.8 contain details for the improved technologies.

5-12Table 5.4.1 Baseline Design Options for Envelope, Non-DisplayDesign OptionsND.C. SmallND.C.MediumND.C. LargeND.F. SmallND.F.MediumND.F. LargeWall and Ceiling Insulation ThicknessBaselineThickness, 4"BaselineThickness, 4"BaselineThickness, 4"BaselineThickness, 4"BaselineThickness, 4"BaselineThickness, 4"Floor Insulation OptionBaselineFloorBaselineFloorBaselineFloorBaselineFloorBaselineFloorBaselineFloorInsulation Materials ABaselineInsulationMaterial,XPS/PU Avg.BaselineInsulationMaterial,XPS/PU Avg.BaselineInsulationMaterial,XPS/PU Avg.BaselineInsulationMaterial,XPS/PU Avg.BaselineInsulationMaterial,XPS/PU Avg.BaselineInsulationMaterial,XPS/PU Avg.Insulation Materials BNoneNoneNoneNoneNoneNoneDisplayDoorEnhancement------Sealant EnhancementBaselineGasketBaselineGasketBaselineGasketBaselineGasketBaselineGasketBaselineGasketActive Infiltration Reduction DevicesNoneNoneNoneNoneNoneNonePassive Infiltration Reduction DevicesNo DeviceNo DeviceNo DeviceNo DeviceNo DeviceNo DeviceDoor SystemsBaseline doorclosingmechanismsBaseline doorclosingmechanismsBaseline doorclosingmechanismsBaseline doorclosingmechanismsBaseline doorclosingmechanismsBaseline doorclosingmechanismsAnti-SweatHeaters------Lighting:Display------Lighting: Non-DisplayCompactFlorescentBulbCompactFlorescentBulbCompactFlorescentBulbCompactFlorescentBulbCompactFlorescentBulbCompactFlorescentBulbAdditional Control SystemNo ControlNo ControlNo ControlNo ControlNo ControlNo Control5-13Table 5.4.2 Baseline Design Options for Envelope, DisplayDesign OptionsD.C. SmallD.C. MediumD.C.LargeD.F. SmallD.F. MediumD.F. LargeWall and Ceiling Insulation ThicknessBaselineThickness, 4"BaselineThickness, 4"BaselineThickness, 4"BaselineThickness, 4"BaselineThickness, 4"BaselineThickness, 4"Floor Insulation OptionBaseline FloorBaseline FloorBaseline FloorBaseline FloorBaseline FloorBaseline FloorInsulation Materials ABaselineInsulationMaterial,XPS/PU Avg.BaselineInsulationMaterial,XPS/PU Avg.BaselineInsulationMaterial,XPS/PU Avg.BaselineInsulationMaterial,XPS/PU Avg.BaselineInsulationMaterial,XPS/PU Avg.BaselineInsulationMaterial,XPS/PU Avg.Insulation Materials BNoneNoneNoneNoneNoneNoneDisplay Door EnhancementBaseline GlassBaseline GlassBaseline GlassBaseline GlassBaseline GlassBaseline GlassSealant EnhancementBaselineGasketBaselineGasketBaselineGasketBaselineGasketBaselineGasketBaselineGasketActive Infiltration Reduction DevicesNoneNoneNoneNoneNoneNonePassive Infiltration Reduction DevicesNo DeviceNo DeviceNo DeviceNo DeviceNo DeviceNo DeviceDoorSystems------Anti-Sweat HeatersNo ControllerNo ControllerAnti-SweatHeaterControlsNo ControllerNo ControllerAnti-SweatHeaterControlsLighting: Display5 foot, T8Electronic,NormalLumen Blub,Normal BFElectronicBallast5 foot, T8Electronic,NormalLumen Blub,Normal BFElectronicBallast5 foot, T8Electronic,NormalLumen Blub,Normal BFElectronicBallast5 foot, T8Electronic,NormalLumen Blub,Normal BFElectronicBallast5 foot, T8Electronic,NormalLumen Blub,Normal BFElectronicBallast5 foot, T8Electronic,NormalLumen Blub,Normal BFElectronicBallastLighting:Non-Display------Additional Control SystemNo ControlNo ControlNo ControlNo ControlNo ControlNo Control5-14Table 5.4.3 Baseline Design Options for Refrigeration SystemsDesign OptionDC.M.IDC.M.OMC.MDC.L.IDC.L.OMC.LEvaporator CoilStandard CoilStandard CoilStandard CoilStandard CoilStandard CoilStandard CoilEvaporator Fan MotorControllersNo ControlsNo ControlsNo ControlsNo ControlsNo ControlsNo ControlsEvaporator Fan BladesStandard BladesStandard BladesStandard BladesStandard BladesStandard BladesStandard BladesCondenser Coil for DCStandard CoilStandardCoil-Standard CoilStandard Coil-Condenser Fan Motorsfor DCPermanent SplitCapacitor MotorPermanent SplitCapacitor Motor-Permanent SplitCapacitor MotorPermanent SplitCapacitor Motor-Condenser Fan Bladesfor DCStandard BladesStandard Blades-Standard BladesStandard Blades-Compressor Type forDCHermeticCompressorHermeticCompressor-HermeticCompressorHermeticCompressor-Defrost Controls forXX.L---Timed DefrostTimed DefrostTimed DefrostFloating Head PressureDC.X.O-Fixed HeadPressure--Fixed HeadPressure-5-15

### 5.4.4 Details for Envelope Design Options

Table 5.4.4 summarizes the design option code s and descriptions for each envelope design option. Sections 5.4.4.1 through 5.4.4.8 cont ain details for improved technologies for envelopes.

5-16

### Table 5.4.4 Design Option Codes and Descriptions for Envelopes

Design Option Code Description
Wall and Ceiling Insulation Thickness

TCK1 Baseline Thickness

TCK2 10% Thicker Insulation

TCK3 25% Thicker Insulation

TCK4 50% Thicker Insulation

TCK5 75% Thicker Insulation
Floor Insulation Option

FLR1 Baseline Floor

FLR2 Cooler and Enhanced Freezer Floor

FLR3 Enhanced Floor

Insulation Materials A

INS1 Baseline Insulation Material, XPS and PU

Insulation Materials B

NONE None

INSH1 Hybrid 1-VIP + INS1

VIP Vacuum insulated Panel
Display Door Enhancement

DR1 Baseline Glass

DR2 Enhanced 1

DR3 Enhanced 2

DR4 Superenhanced

Sealant Enhancement

SE1 Baseline Gasket

XC Extra Caulking

ATG Advanced Tongue and Groove and Door Sweep

Active Infiltration Reduction Devices

NOARD None

AC Air Curtain

Passive Infiltration Reduction Devices

NOIRD Baseline No Device

SC Strip Curtain
Door Systems

DRSTD Baseline door closing mechanisms

VEST Vestibule

Anti-Sweat Heaters

ASHNC Baseline (No Controller)

ASCTRL Anti-Sweat Heater Controls
Lighting: Display

T8 5 foot, T8 Electronic, Normal Lumen Blub,

Normal BF Electronic Ballast

LED 5 foot, LED
Lighting: Non-Display

CFL Compact Florescent Bulb

LED LED Bulb
Control System

CS1 Baseline No Control

5-17CS2 Lighting Sensors

CS3 Lighting sensors and Door Opening Control



### 5.4.4.1 Improved Wall, Ceiling, and Floor Insulation

Wall and Ceiling Insulation Thickness

The thermal resistance of insulating materials increases approximately linearly with material thickness. Based on DOE’s analysis and public comment, a typical WICF utilizes four

inches of foam insulation in the walls and ceilin g to slow the rate of heat conduction from the external environment to the internal cooled space of the walk-in. In addition, DOE found that many WICF manufacturers offer insulation in thicknesses of four, fi ve and six inches.

Therefore, in the engineering analysis, DOE c onsidered insulation thickness as one of the two independent variables that impacts full wall R-value. DOE assessed the incremental increase

in cost due to additional materi al cost and separately evaluated the impact on shipping cost. Details of the analysis for material/labor a nd shipping cost are found in Table 5.4.5 through

Table 5.4.8 below.

Table 5.4.5 Details for “Wall and Ceiling In sulation Thickness” Design Option

Code Description Thickness [inch] Extra Material/Labor Cost [$/ft 2 ]

TCK1 Baseline Thickness 4.0 $ ­

TCK2 10% Thicker Insulation 4.4 $ 0.220

TCK3 25% Thicker Insulation 5.0 $ 0.550

TCK4 50% Thicker Insulation 6.0 $ 1.130

TCK5 75% Thicker Insulation 7.0 $ 1.710



### Table 5.4.6 Details for “Wall and Ceiling Insu lation Thickness” De sign Option Cont.

Thickness [in] Calc. Type Units Calculation Slope Intercept

4
Weight lbs Calculated 1.884 311.040

5 Calculated 2.014 334.960

6 Calculated 2.198 322.190

4 Shipping

Cost- Base $ Calculated 0.353 -102.670

5 Calculated 0.353 -102.670

6 Calculated 0.353 -102.670

4 Shipping

Cost- Fuel $ Calculated 0.102 -76.074

5 Calculated 0.102 -76.074

6 Calculated 0.102 -76.074

5-18

### Table 5.4.7 Details for “Wall and Ceiling Insu lation Thickness” De sign Option Cont.

Total

External

Area Thickness

Input From

Model From Model Slope Intercept

Output Weight Interpolated lbs Calculated Calculated

Base Interpolated $ Calculated Calculated

Fuel Interpolated $ Calculated Calculated

Total Interpolated $ Calculated Calculated



### Table 5.4.8 Total Shipping Cost for Product Classes and Thicknesses Considered

Design Option TCK1 TCK2 TCK3 TCK4 TCK5

Wall Thickness [Inch] 4 4.4 5 6 7

ND.C. Small $ 266.19 $ 277.26 $ 293.87 $ 321.56 $ 349.24

ND.C. Medium $ 688.01 $ 713.19 $ 750.96 $ 813.91 $ 876.87 ND.C. Large $1,729.36 $1,789.36 $1,87 9.38 $2,029.40 $2,179.42

D.C. Small $ 130.69 $ 137.23 $ 147.05 $ 163.40 $ 179.76

D.C. Medium $ 249.01 $ 259.51 $ 275.25 $ 301.50 $ 327.75 D.C. Large $2,218.50 $2,294.87 $2,40 9.42 $2,600.34 $2,791.25

ND.F. Small $ 228.52 $ 238.33 $ 253.06 $ 277.59 $ 302.13

ND.F. Medium $ 741.70 $ 768.67 $ 809.14 $ 876.58 $ 944.02
ND.F. Large $1,737.88 $1,798.17 $1,88 8.61 $2,039.34 $2,190.08

D.F. Small $ 161.37 $ 168.94 $ 180.29 $ 199.21 $ 218.13

D.F. Medium $ 309.85 $ 322.39 $ 341.19 $ 372.52 $ 403.86
D.F. Large $3,241.10 $3,351.67 $3,51 7.52 $3,793.94 $4,070.35



### DOE’s analysis found that the incremental cost of manufacturing thicker products was dominated by material cost. The results of the an alysis, for the various thicknesses, are shown in

“Extra Material/Labor Cost” column of Table 5.4.5. The impact on shipping is a more complex calculation based on the final weight of a WICF product. The shipping weight is independently impacted by both the total surface area (or size) of a walk-in and selected insulation thickness. Then, the cost of shipping is dependent on a base charge (based on density and shipping class) and a fuel surcharge based on th e distance shipped and weight.

Due to the multivariate nature of this calcu lation, best fit linear equations were first developed to calculate the weight of a given pr oduct based on its surface area and thickness (the slope and intercepts are shown in Table 5.4.6 abov e). Then using the calculated weight for a given thickness and area, the base and fuel cost of shipping could be de veloped. Finally, linear best fits of the shipping cost calculations were made as shown in Table 5.4.7. These last equations then allowed the model to interpolate the shipping cost based on any thickness ranging

from two to seven inches in thickness. Table 5.4.8 shows the baseline calculations of shipping weight and cost for all product classes.

5-19

### Floor Insulation

Since floor insulation is generally selected independently in standard WICF design practice, the floor insulation was treated as such in the engineering analysis. In addition, EPCA specified that insulated floors with a minimum of R-28 are required for walk-in freezers (not for coolers), requiring that freezers and coolers be treated differently. Therefore, DOE selected an

uninsulated floor and four inches of insulati on (approximately equiva lent to R-28) for the baseline options for walk-in coolers and freezers respectively. Due to the inherently complex heat transfer physics of floor heat transfer, DOE developed finite element analysis (FEA) models to numerically solve for the average heat flux through the floor of WICF. The models used assumed design operating temperat ures of -10 °F for freezers and 35 °F for coolers. The FEA results, for various floor sizes, are shown belo w in Table 5.4.9. FLR1 is the baseline option for

both coolers and freezers while FLR2 and FLR3 reflect results of increasing thickness of

insulation.

Table 5.4.9 Details for “Floor Insula tion” Design Opti on, FEA Results

FEA Results Average Heat Flux [Btu/h-ft 2 ]

Floor Area [ft 2 ] FLR1 FLR2 FLR3

Cooler 36 8.61 1.48 1.21

71.4 7.31 1.43 1.18

80 6.9 1.41 1.17

240 4.4 1.31 1.1

750 2.97 1.13 0.97

1200 3.04 1.18 1.01

Freezer 36 3.15 2.59 2.2

48 3.11 2.56 2.18

71.4 3.04 2.51 2.14

180 2.88 2.4 2.06

500 2.54 2.16 1.88

1200 2.51 2.14 1.86



### Table 5.4.10 shows the design option inputs used to complete the FEA simulations:

Table 5.4.10 Details for “Floor Insula tion” Design Option, FEA Inputs

Code Description Thickness

Cooler Thickness

Freezer R-value

Cooler R-value

Freezer

FLR1 Baseline Floor 0 4 0.0 22.42

FLR2 Cooler and Enhanced

Freezer Floor 4.00 5.00 22.42 28.03

FLR3 Enhanced Floor 5.00 6.00 28.03 33.64



### Floor construction, when a WICF manufactu rer provides the floor, is similar to the typical WICF wall panel construction. Therefore, the same cost model fo r WICF wall panels was

5-20

### used to calculate the incremental cost increase for each design option. The results used in the engineering analysis are shown in Table 5.4.11.

Table 5.4.11 Details for “Floor In sulation” Design Option, Cost

Code Normalized

Insulation Cost [$/ft2]

Cooler Normalized

Insulation Cost [$/ft2]

Freezer

FLR1 $0.00 $6.66

FLR2 $6.66 $7.23

FLR3 $7.23 $7.88



### Insulation Materials A

Based on DOE analysis and stakeholder comments, DOE concluded that WICF manufacturers almost exclusively currently use on e of two foam insulation types: board stock extruded polystyrene (XPS) or foam-in-place polyurethane (PU) iii 

### . The thermal resistance performance characteristics of each product type are quite similar, as well as the total cost associated with a given material. Therefore, DOE averaged the material properties for the baseline design option as shown in Table 5.4.12. This represents the second of the two independent variables that impact full wall R-value (insulation thic kness, the first, was described earlier). Since foam materials were considered the baseline option, foam materials are considered to have zero cost when compared to additional material options.

Table 5.4.12 Details for “Insulation Materials A” Design Option

Code Description R-value/inch composite

INS1 Baseline Insulation Material, XPS and PU 5.902



### Insulation Materials B

DOE found that several other insulating materi als or systems are commercially available

but have limited market penetration. These include, but ar e not limited to, vacuum insulated panels (VIPs), aerogel materials, and hybrids of these and traditiona l foam materials. In order to account for these high R-value (and generally high cost) alternatives, DOE incorporated these options into the engineering analysis. The cost and performance data are based on discussions with manufacturers and DOE internal analysis. DOE estimated that the cost of R-10/inch aerogel was $ 8.00-$13.00 or approximately $1.00/[ ft 2 

### -F-h/Btu/inch]. DOE found that thin VIPs encased in standard foam (represented by INSH1) and VIPs alone have $/[ft 2 

### -F-h/Btu/inch]ratios of approximately $0.10 and $0.13 respectively. For comparison, DOE estimates that standard foam such as XPS or PU has a cost-performance ratio of $0.02 /$/[ft 2 

### -F-h/Btu/inch]. DOE concluded that at current market pri ce and performance per inch, aerogel products are not a viable

alternative to VIPs for use in walk-in coolers a nd freezers and therefore were not included in the engineering analysis.

5-21

### Table 5.4.13 Details for “Insulatio n Materials B” Design Option

Code Description Wall

Thickness % Wall

Thickness % Full

Thickness

[inch]

NONE None

INSH1 Hybrid 1-VIP +

INS1 75% 25% 2

VIP Vacuum

Insulated Panel 100% 0% 2



### Table 5.4.14 Details for “Insulation Mat erials B” Design Option, Continued

Code Other

InsulationCost [$/brdft] Foam

Insulation

Cost [$/brd-ft] Insulation Cost [$/ft 2 ]

@ 2"

Thickness composite Other Rvalue/

inch Foam

R-value

/inch R-value

/inch composite R-value composite

@ Full

Thickness

NONE

- - - - - - -

INSH1 $3.88 $0.40 $6.02 37.00 5.90 29.15 58.30

VIP $4.70 $0.00 $9.40 37.00 37.00 37.00 74.00



### In order for a manufacturer to incorporate these advanced insulating materials, significant engineering and tooling costs would be incurred. These costs are amortized over the life of the equipment and divided by the assumed annual unit production. The result is levelized cost per square foot of WICF panel produced. These a ssumptions and calculations are shown in Table

5.4.15 and Table 5.4.16 below.

Table 5.4.15 Details for “Insulation Material s B” Design Option , Engineering Cost

Engineering Costs

Design Option INSH1 VIP

Description Hybrid 1-VIP +

INS1 Vacuum Insulated

Panel

Assumed costs to

design system, manufacturing process, and tooling $ 200,000.00 $ 500,000.00

New Equipment Cost $ 150,000.00 $ 300,000.00

Design Lifetime
[Years] 7 7

Units per Year

[unit = ft2] 11,200,000 11,200,000

Cost Per Unit [ft2]* $ 0.004 $ 0.010

*Assuming 4’ X 8’ panel

5-22

### Table 5.4.16 Details for “Insulation Materials B” Labor Cost

Labor Costs

Item Hy brid 1-VIP +

INS1 Vacuum Insulated

Panel

Additional Labor [minutes/per panel] 10 15

Labor Rate [$/Hr] $ 24.00 $ 24.00

Cost Per Unit [ft2] $ 0.13 $ 0.19



### 5.4.4.2 Improved Door Gaskets and Panel Interface Systems

Sealant Enhancement

The main pathway for air exchange during st eady-state operation of WICF is through the panel-to-panel interfaces and door gaskets. In pa rticular, non-display type doors that utilize door sweeps are prone to slight air leakage. Typical WICF construction consists of a cam-lock system that squeezes neighboring panels together. This provides a compression force on gaskets that are normally placed between the panels, creating a reasonably well sealed interface. DOE considered this type of construction the baseline option in the engineering analysis. However, additional designs exist that utilize tongue-and-groove construction (see Figure 5.4.1 below) and novel locking systems that further redu ce air exchange. In addition, simply adding additional sealant to the panel-to-panel and panel-to-floor interface may reduce air infiltration. Both the advanced and simple improvements are reflected in Advanced Tongue and Groove (ATG) and Extra Caulking (XC) and design options in the engineering analysis.

Figure 5.4.1 Panel Tongue and Groove Construction

DOE research found that advanced tongue and groove design is capable of reducing

infiltration rates to at least 0.06 ft 3 

### /h-ft 2 

### (flow rate per unit of external surface area). The resulting calculations for each product class and analysis point are shown in Table 5.4.17 and Table 5.4.18 below. Advanced tongue-and-groove design wa s considered the max-tech option, and the corresponding infiltration rate wa s used to reverse calculate th e performance of the previous design options in the engineering analysis. DOE estimated that about one third of the total steady-state infiltration was caused by losses through the door sweep of non-display WICF passage doors.

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### Table 5.4.17 Details for “Sealant Enhancement” Design Option

Code Description Material [$/ft2] or [$/lin-ft]

SE1 Baseline

Gasket $ ­

XC Extra Caulking $ 0.09

ATG Advanced Tongue and

Groove and Door Sweep $ 1.23



### Table 5.4.18 Details for “Sealant E nhancement” Design Option, Cont.

Total

External

Surface

Area Display

Doors Passage

Doors Freight

Doors SE1 XC ATG

Units ft 2

- ft 3 /h

ND.C.

Small 433 0 1 0 56 50 28

ND.C.

Medium 1088 0 1 1 141 125 70

ND.C. Large 2820 0 2 1 487 447 218

D.C.

Small 230 3 1 0 30 26 15

D.C.

Medium 404 8 1 0 52 47 26

D.C. Large 3844 50 2 0 664 609 297

ND.F.

Small 309 0 1 0 40 36 20

ND.F.

Medium 911 0 1 1 118 105 59

ND.F. Large 2080 0 2 1 359 329 161

D.F.

Small 230 3 1 0 30 26 15

D.F.

Medium 404 8 1 0 52 47 26

D.F. Large 3844 50 2 0 664 609 297



### The assumptions used to calculate the incremental cost associated with each design option are shown in Table 5.4.19 through Table 5.4.21 below.

5-24

### Table 5.4.19 Details for “Sealant Enhancem ent” Design Option, Engineering Cost

Engineering Costs Advanced Tongue

and Groove Advanced Door Sweep

Item Value Value

Assumed costs to design system, manufacturing process, and tooling $ 100,000.00 $ 80,000.00

New Equipment Cost $ 50,000.00 $ 25,000.00
Design Lifetime [Years] 7 7
Units per Year [unit = ft 2 ] 11200000 14400

Cost Per Unit $ 0.002 $ 1.042



### Table 5.4.20 Details for “Sealant Enhan cement” Design Op tion, Labor Cost

Labor Costs Advanced Tongue

and Groove Advanced Door Sweep

Item Value Value

Additional Labor [minutes] 5 10
Labor Rate [$/h] $ 24.00 $ 24.00

Cost Per Unit $ 0.06 $ 0.13



### Table 5.4.21 Details for “Sealant Enhancem ent” Design Option , Material Cost

Caulking Assumptions

Item Value

Tube Size [Fluid Oz] 10
Tube Cost [$] $ 4.00

Cross-sectional Area of Bead [inch 2 ] 0.0351

Volume of Caulk [Fl Oz/Lin-ft] 0.233
Linear Feet per Tube 42.85
Cost per Linear Foot $ 0.09



### 5.4.4.3 Electronic Lighting Ballasts and High-Efficiency Lighting

Since the associated lighting systems for display and non-display type WICF are quite different, DOE split the lighting engineering analysis by the display and non-display characteristic. This helped simplify the model calculations and provides more clarity on design options used.

Lighting: Display

EPCA specified minimum efficacy of 40 lume ns/W, including ballast losses, for all lights. (42 U.S.C. 6313(f)(1)(G) Therefore, DOE di d not consider any lighting systems that did not meet this limit. In addition, DOE analysis i ndicated that the lighting industry had mostly shifted to high efficiency, electronic ballasted lig hting systems. DOE also noted that a number of display door manufacturers have eliminated th e use of florescent systems and now use LED lighting systems as their baseline option. DOE is considering the use of LEDs as the baseline option but completed the preliminary engineering analysis using T8 bulbs with electronic ballasts

5-25

### as the baseline option. The associat ed performance and cost data used in the model are shown in Table 5.4.22 through Table 5.4.25 below.

Table 5.4.22 Details for “Lighting: Disp lay” Design Option, Performance Data

Code Description Lamp Power [W/bulb] Ballast Power [W/bulb]

T8 5 foot, T8 Electronic, Normal Lumen Blub, Normal BF

Electronic Ballast 54.5 3.5

LED 5 foot, LED 16.1 0.0



### Table 5.4.23 Details for “Lighting: Display” Design Option, Performance Data Cont.

Lamp Ballast System

Code
Type Rated

Power

[W] Rated

Lumens Number

of Lamps Ballast

Factor Total Input Power [W] Efficacy [LPW] Light Output [Lumens]

T8 F32T8/HL 58.0 3100 1 0.94 58.0 50.2 2914.0

LED

- 16.1 1342 1 1.00 16.1 53.9 1342.0



### Table 5.4.24 Details for “Lighting: Di splay” Design Option, Cost Data

Cost

Code Description Lamp Ballast Total

T8 5 foot, T8 Electronic, Normal Lumen Blub, Normal BF

Electronic Ballast $10.99 $14.00 $24.99

LED 5 foot, LED $115.00

- $115.00



### Table 5.4.25 Details for “Lighting: Disp lay” Design Option, Cost Data Cont

Description Avg. OEM Price
120-277V Electronic Ballast T8 lamps (-20F starting capability) $14.00

Description Average

Wholesale Price

5' 58W T8 low-temp lamp $10.99

LED System Cost Estimate Value

LED power use, 1-row 5' fixture [W] 16.1

Average OEM Cost of 1-row 5' LED fixture $115.00



### Lighting: Non-Display

As for display type walk-ins, DOE only considered design options with at least 40 lumens/W efficacy for non-display WICF. The two readily available technologies that meet this standard are light emitting diode (LED) bulbs and compact florescent light (CFL) bulbs. LED bulbs are higher performing and significantly more expensive than CFLs, therefore DOE selected CFLs as the baseline design option for non-display systems. The data used for calculations in the engineering analysis are shown in Table 5.4.26.

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### Table 5.4.26 Details for “Lighting: Non-Display” Design Option

Code Description Bulb

Power [W/bulb] Ballast

Power Bulb

Cost

[$] Rated

Power

[W] Rated

Lumens Efficacy [L/W]

CFL Compact

Florescent

Bulb 13.0 2.0 $1.50 15.0 825.0 55.0

LED LED Bulb 7.0

- $35.00 7.0 450 64.3



### 5.4.4.4 Occupancy Sensors and Automatic Do or Opening and Closing Systems

Control Systems

DOE reviewed a number of control system re lated design options. While most control systems are designed to intelligently control the refrigeration equipment, there are a number of

available features that are relevant to th e envelope only. DOE found that most WICF manufacturers offer control systems but that there was limited end-user demand or market penetration. The exception was for anti-sweat heat er controllers, which will be discussed in another section. Therefore, DOE considered the ba seline design option to be a WICF without any type of control features, CS1.

The next design option (CS2) DOE considered is occupancy sensors to control lights. This allows for “on demand” use of lights a nd helps prevent accidental wasted energy. As described in the proposed WICF te st procedure, DOE recognizes that actual energy use will vary based on specific walk-in use or type. 75 FR 199. Th erefore, the engineering analysis adopts the same assumption for percent time off (PTO) of devices that are regulated by control systems. The assumptions used in the analysis can be found in Table 5.4.27. The last option, CS3, incorporates the use of an automatic door opening and closing sensor. Using the same methodology in the WICF test procedure, the us e of the automatic door devices is assumed to reduce the average time that a door remains open dur ing each opening event. This reduces direct air infiltration through the door and corresponding energy use by the refrigeration equipment.

Table 5.4.27 Details for “Control Systems” Design Option

Code Description PTO Lights Automatic

Door Open/Close PTO

Other Cost

CS1 Baseline No Control 25% NO 0% $ ­

CS2 Lighting Sensors 50% NO 0% $ 250.00

CS3 Lighting sensors and Door Opening Control 50% YES 25% $ 450.00



### The cost estimates used for the various control system options were developed based on component and WICF manufacturer comments.

5.4.4.5 Air Curtains and Strip Curtains

Active Infiltration Reduction Devices

5-27

### Active infiltration reduction devices (AIRDs), such as an air curtain, are devices that reduce air infiltration through open doorways that consume energy in order to function. While both passive and active devices serve the same pur pose, DOE considered it important to classify them differently. AIRDs’ cost be nefit ratio (and associated payback period) is dependent on the ratio of energy saved versus the energy used to operate the device rather than simply the energy saved for passive devices. In a ddition, active devices needed to be considered independently of passive devices as it is possible for these devices to be installed simultaneously in an actual walk-in. For example, strip curtains can serve as the primary method to reduce air exchange while an air curtain can act as a secondary reduction method.

DOE considered air curtains as the only viab le AIRD for walk-ins. The performance of these devices is normally measured in terms of effectiveness. An effectiveness of 1.0 corresponds to a device that prevents 100% of air exchange from occurring when a door is open. Conversely, an effectiveness of zero means that the device does not reduce air exchange by a

measureable amount. DOE assumed that the effectiv eness of an air curtain, based on extensively

cited ASHRAE research iv 

### , is 0.8.

There is limited market penetration of air curtains, particularly for smaller sized WICF. Therefore, DOE selected a system without an air curtain for the baseline option.

Table 5.4.28 Details for “Active Infiltrati on Reduction Devices ” Design Option

Code Description Effectiveness $/door Rated Power [W]

NOARD None 0.00 $ ­

AC Air Curtain 0.80 $ 460.00 500.00



### Passive Infiltration Reduction Devices

Strip curtains are the most wi dely used passive infiltrati on reduction devices (PIRDs) in WICF today. In addition, EPCA cites strip curtains as one “method of minimizing infiltration when doors are open.” However, DOE research found that throughout the industry there is limited preference to use vertically hung strip curtains in walk-ins. End-users complain that the vinyl strips are a nuisance becaus e the strips brush against personnel’s faces and heads as they pass through the door. Therefore, WICF manufa cturers typically select other methods to maintain EPCA compliance, such as spring hinged doors.

Another option DOE considered was impact doors. These have been shown to have nearly identical effectiveness as strip curtains and are equally if not more transparent than strip curtains. Impact doors are generally constructe d of two large overlapping transparent plastic flaps that are connected to the door frame using bi-directional hinges. After pushing through the flaps, the spring hinges swing the two flaps back into place to reduce air exchange. Since the flaps open to the sides, rather than being verti cally hung like strip curtai ns, the material does not drag over the face or arms of personnel passing through the doorway. DOE has found that this is an important feature when c onsidering end-user adoption.

5-28

### However, impact doors are nearly twice as co stly as strip curtains. While impact doors appear to be a practical alternative, the design options must be ordered such that the first option has the shortest payback period a nd the last has the longest payback. If the options do not follow this order then the engineering analysis produces nonsensical results. Compared to strip curtains, impact doors always have a higher cost but iden tical performance and therefore always have a longer payback period. Both because of the long er payback period and that the options have the same effectiveness, impact doors would never be selected in th e model. For these reasons, DOE only considered strip curtains as a design option for PIRD.

The assumed strip curtain effectiveness and cost estimates are shown in Table 5.4.29 below. Strip curtains used for freezers must rely on materials that do not become brittle and/or fracture at low temperatures. Therefore, freezer strip curtains are typically more expensive than cooler strip curtains as shown in Table 5.4.29.

Table 5.4.29 Details for “Passive Infiltra tion Reduction Devi ces” Design Option

Cooler Freezer

Code Description Effectiveness Cost [$/ft2] Cost [$/ft2]

NOIRD Baseline No Device 0.00 $ ­ $ ­

SC Strip Curtain 0.90 v $ 4.33 $ 5.28



### 5.4.4.6 Vestibule Entryways

Door Systems

In addition to passive and active IRDs, DOE considered unique walk-in designs that could reduce the amount of air infiltration during door opening events. As described in Chapter 4 revolving door systems were not considered in the engineering analysis due to impact on utility of the WICF. However, unlike revolving doors, ve stibule entry ways are occasionally used for walk-ins. These entry ways are very effective at reducing direct air exchange. When the primary door is accessed the secondary door remains closed (see Figure 5.4.2). When the secondary door opens, th e primary has already closed, substantially reducing air movement. In the engineering analysis, DOE created a design option that incorporates this design as shown in Table 5.4.30 below. For the cost and effectiveness, DOE only considered designs that utilized a standard WICF insulated hinged door as the primary and the secondary doors. Variations such as the primary or secondary entry way only protected by an air or strip curtain were not considered. The co st also includes the expense of additional wall panels that would be required to enclose th e intermediate space between the primary and secondary entry-ways.

5-29

### Vestibule

Secondary Door

or IRD Primary Door

and/or IRD WICF

Figure 5.4.2 Overhead View of Wal k-In and Vestibule Entryway

Table 5.4.30 Details for “Door Systems” Design Option

Code Description Effectiveness $/system

DRSTD None 0.00 $ ­

VEST Vestibule 0.98 v i $1,000.00



### 5.4.4.7 Display and Window Glass Syst em Insulation Enhancement

Display Door Enhancement

Heat conduction through glass display doors is one of the largest energy loss components

of a walk-in. The heat that is transferred t hough the doors is primarily dependent on the door frame material and insulation, the number and spacing of glass pane s, the type of inert gas fill and the use of various low-emissivity coatings . DOE found that typical display doors use vinyl composite frames and argon gas fill. EPCA specified that, at a minimum, cooler and freezers display doors must utilize two and three pane doors respectively. Therefore, DOE selected these characteristics for the baseline options for cool ers and freezers as show in Table 5.4.33 and Table

5.4.34 below. Starting from this baseline DOE then considered additional design options DR2, DR3 and DR4. DR2 reflects the display door ch aracteristics widely available for high performance display doors. DR3 and DR4 which incorporate multiple panes, additional coatings and higher performing gas fill corresponding to the mid and maximum performance technologies

available.

5-30

### Table 5.4.31 Details for “Display Door Enhancement” Design Option

Cooler Freezer Cooler Freezer

Code Description Overall UFactor at 75F [Btu/hr-fF] Overall UFactor at

75 F[Btu/hr-fF] Cost [$/ft 2 ] Cost [$/ft 2 ]

DR1 Baseline Glass 0.432 0.303 $64.29 $71.43

DR2 Enhanced 1 0.269 0.262 $88.93 $90.82

DR3 Enhanced 2 0.123 0.123 $112.97 $129.39

DR4 Superenhanced 0.080 0.080 $146.18 $155.21



### Due to limited availability of component ma nufacturer thermal performance data, DOE predicted the performance of the various design options using Lawrence Berkeley National Lab’s (LBNL) Window 5.2 program. As specified in the WICF test procedure NOPR, this is a widely used and verified tool for calculating perf ormance of glass doors. 75 FR 186. The key assumptions, shown in Table 5.4.32, were used to ge nerate the performance data shown in Table

5.4.31. The predicted U-value from Window 5.2 is a full door system prediction including the center of glass, door frame etc.

Table 5.4.32 Details for “Display Door E nhancement” Design Option, Window 5.2

Assumptions used in Window 5.2 calculations:

• Clear glass is 0.125" thick • Low-E glass is 0.125" thick clear glass with low-E coating (emissivity=0.54)

• 0.5" thick gas layer for Argon, 0.3" for Krypton/Xenon
• 100% purity gas filled windows

• R-value of full thickness frame = 2.15 ft2-F-h/Btu

Source: LBNL WINDOW 5.2 Software



### Table 5.4.33 Details for “Display Door Enhanc ement” Design Option, Window 5.2, Coolers

Coolers Frame Number of

Panes Glass type: Pane

1 Glass
type:

Pane 2 Glass
type:

Pane 3 Glass
type:

Pane 4 Gas Fill

Baseline Vinyl/Composite 2 Clear Clear

- - Argon

Enhanced 1 Vinyl/Composite 3 Low-E Clear Low-E

- Argon

Enhanced 2 Vinyl/Composite 4 Low-E Clear Clear Low-E Krypton

Superenhanced Vinyl/Composite 4 Low-E Low-E Low-E Low-E Xenon

5-31

### Table 5.4.34 Details for “Display Door E nhancement” Design Option, Window 5.2,

Freezers

Freezers Frame Number

of Panes Glass
type:
Pane 1 Glass
type:
Pane 2 Glass
type:
Pane 3 Glass
type:
Pane 4 Gas Fill

Baseline Vinyl/Composite 3 Clear Clear Clear

- Argon

Enhanced 1 Vinyl/Composite 3 Low-E Clear Low-E

- Krypton

Enhanced 2 Vinyl/Composite 4 Low-E Clear Clear Low-E Krypton
Superenhanced Vinyl/Composite 4 Low-E Low-E Low-E Low-E Xenon



### Table 5.4.35 Details for “Display Door Enha ncement” Design Option, Gas Fill Cost

Incremental Cost of Krypton and Xenon
Take Size (liquid) 64 Liters

Cost Per Liter $23.00 $/Liter

Cost Per Tank $1,472.00 $/Tank

Pressure 2300 PSI
Expanded Volume 10014 Liters
Cost Per Liter (expanded) $ 0.15 $/Liter
Liters Per Gap 10.36 Liters
Cost Per Gap $1.52 $

Krypton, Cost Per ft2 $0.11 $

Xenon, Cost Per ft2 $0.21 $

Source: Discussion with wholesale gas companies



### 5.4.4.8 Anti-sweat Heater Controls and No Anti-sweat Systems

Anti-Sweat Heaters

The external surface of glass display doors typi cally cool to temperatures below the dew point of the surrounding air. When this occurs , condensate or “sweat” begins to form on the exposed surface of the glass. It first appears as a fog, and if left unchecked, further condenses to droplets large enough to begin to roll and drip o ff the surface. The amount and rate of sweating is dependent on the relative humidity surrounding the wa lk-in and the temperature of the glass. In order to ensure the temperature of the glass stays above the dew point of the surroundings,

electric resistive heater wire is installed around the frame of the door. Typical systems, regardless of the relative humidity, continuously power the heater wire. This means that for a large portion of time, the door glass is heated to te mperatures far higher than necessary to remain above the dew point, resulting in a dditional electricity consumption.

With the use of an anti-sweat heater control system that senses the relative humidity, the level of heating required to a void condensate can be precisely matched to the conditions. The energy savings seen in practice for freezers a nd coolers is approximate ly 50 percent and 75 percent, respectively.

5-32

### Therefore, DOE set the baseline option of di splay walk-ins to not include anti-sweat heaters and the next design option, ASCTRL, to in clude their use. Since fr eezers operate at much colder temperatures than coolers, the wattage required for freezer heater wire is higher to ensure the appropriate door temperature is achieved. See Table 5.4.36 for details.

In recent years the cost of anti-sweat controls has dropped significantly. A number of display door manufacturers now offer the controls as a standard option. A single $100 controller is capable of controlling up to five doors, so the average cost on a per door basis is approximately $20.00 vii



### .

As described above, sweating is a function of glass temperature and the dew point (or relative humidity) of the surrounding air. The exte rnal surface of the glass experiences such low temperatures because of the low resistivity of most glass doors. However, as the thermal resistance to heat transfer of the glass door increases, the glass surface temperature also increases. Therefore, if the glass door has high en ough thermal resistivity it is possible to reduce or entirely eliminate the need for anti-sweat heaters. Based on manufacturer comment, DOE estimated that with display door option DR2, the power for heater wire could be reduced to 1W/ft and for DR3 or DR4, the heater wire could be eliminated.

Table 5.4.36 Details for “Anti-Sw eat Heaters” Design Option

Cooler Freezer Heater wire

Code Description Passage

Door Wire [W/ft] Passage

Door Wire [W/ft] PTO

Cooler PTO

Freezer Cost

ASHNC Baseline (No Controller) 5.40 8.00 0% 0% $­

ASCTRL Anti-Sweat Heater

Controls 5.40 8.00 75% 50% $100.00



### 5.4.5 Details for Refrigeration System Design Options

Table 5.4.37 summarizes the design option code s and descriptions for each refrigeration system design option. Sections 5.4.5.1 through 5. 4.5.8 contain details for improved technologies for refrigeration systems.

5-33

### Table 5.4.37 Design Option Codes and De scriptions for Refrigeration Systems

Design Option Code Description
High-Efficiency Scroll Compressors

HER Hermetic Compressor

SCR Scroll Compressor

Condenser Coil

CD1 Baseline Coil

CD2 Larger Coil

Condenser Fan Motors

PSC Permanent Split Capacitor Motors

ECM Electronically Commutated Motors
Evaporator Fan Blades

EB1 Standard Evaporator Fan Blades

EB2 Improved Evaporator Fan Blades

Condenser Fan Blades

CD1 Standard Condenser Fan Blades

CD2 Improved Condenser Fan Blades
Evaporator Coil

EV1 Baseline Coil

EV2 Larger Coil
Evaporator Fan Control

EM1 Baseline (No Control)

EM2 Evaporator Fan Control
Floating Head Pressure

- Baseline (Fixed Head Pressure)

FHP Floating Head Pressure

Defrost Controls

DF1 Baseline (Timed Defrost)

DF2 Defrost Control



### 5.4.5.1 High-Efficiency Scroll Compressors

The compressor design option applies only to DC equipment classes. In consultation with compressor manufacturers and external design ex perts, DOE determined that two levels of technology were applicable for the compressor design option. The minimum technology level is a standard single-speed hermetic compressor, and the maximum technol ogy level is a scroll compressor. (See section 5.4.2.2 for why two-speed and variable-speed compressors were not considered.) Reductions in total system energy consumption are realized through a reduction in compressor energy consumption.

DOE collected performance data for single-speed hermetic compressors and scroll compressors over a range of capacities applicable to the covered equipment. DOE then selected one representative hermetic compressor and one representative scroll compressor for two different sizes of each equipment class, representing two analytical points for a small and a large unit of each class. The performance data were then used to calculate the power and capacity of the compressors using the 10-coeffici ent method described in section 5.4.9.1.

5-34

### Table 5.4.38 Details for "High-Efficiency Scroll Compressor" Design Option

Class Baseline (Hermetic) Model High Efficiency (Scroll) Model

DC.M.I – Small CS10K6E-PFV ZB10KCE-PFV DC.M.I – Large CS18K6E-PFV ZB19KQE-PFV

DC.M.O – Small CS12K6E-PFV ZX15KCE-PFV DC.M.O – Large CS18K6E-PFV ZX21KCE-PFV

DC.L.I – Small CF06K6E-PFV ZF06K4E-PFV DC.L.I – Large CF12K6E-PFV ZF11K4E-PFV

DC.L.O – Small CF06K6E-PFV ZF06K4E-PFV DC.L.O – Large CF12K6E-PFV ZF11K4E-PFV



### 5.4.5.2 Condenser Coil

This design option applies only to DC equipment classes. DOE considered two technology levels: a standard coil and a larger coil that was sized to run at a saturated condensing temperature (SCT) that is cooler than that of the baseline coil. DOE calculated the temperature difference (TD) between the SCT and the ambient temperature, for the baseline coil. Then DOE considered a theoretical improved coil that ran at an SCT such that the TD was half that of a baseline coil. DOE chose a multiplier rather than a constant decrease because some classes of equipment, such as low temperature equipment, are already set to run at a smaller TD on the condenser. Furthermore, there are heat transfer constraints on how far the TD can be decreased. DOE then calculated the size of the improved coil from the baseline coil, assuming all other characteristics stayed the same, by using the heat transfer equation:

Q & A = 

### Eq. 5.1 U × TD



### where: A = face area of the coil;

Q & 

### = rate of heat transfer;

U = constant coil coefficient TD = temperature difference

Thus, a smaller TD necessitates a larger area. DOE calculated the new area assuming that both the length and the width of the coil woul d change at the same rate. DOE then used the

cost model to calculate the added cost of ma terials to produce the larger coil. Because compressor capacity and power consumption are directly related to SCT, reductions in the energy consumption are realized through an improved normalized energy consumption. Details of the TD multiplier are shown in Table 5.4.39.

Table 5.4.39 Details for "Condenser Coil" Design Option

Code Description TD Multiplier

CD1 Baseline 1

CD2 Improved 0.5

5-35

### For improved condenser coils , DOE assessed the incremental increase in cost due to additional material cost and separately evaluated the impact on shipping cost for each dedicated condensing equipment class and size. The results are shown in Table 5.4.40.

Table 5.4.40 Details for "Condenser Coil" Design Option, Continued

Equipment Class Extra Material/Labor Cost ($) Extra Shipping Cost ($)

DC.M.I – Small $75.77 $12.66 DC.M.I – Large $147.32 $28.33

DC.M.O – Small $191.22 $28.44 DC.M.O – Large $190.80 $28.33

DC.L.I – Small $96.40 $12.74 DC.L.I – Large $155.99 $30.63

DC.L.O – Small $116.59 $12.74 DC.L.O – Large $202.33 $30.63



### 5.4.5.3 Condenser Fan Motors

In conjunction with fan blades, condenser fan motors are necessary for transferring heat from the refrigerant into the ambient air. The c ondenser fan motor design option applies only to the dedicated condensing equipmen t classes. EPCA requires that all condenser fan motors under 1 horsepower be either ECMs (brushless DC motors), PSCs, or 3-phase. (42 U.S.C. 6313(f)(1)(F)) Currently, DOE considers PSC moto rs as the minimum technology and ECMs as the maximum technology. DOE did not consider 3- phase motors in the engineering analysis as discussed in chapter 4 of the preliminary TSD.

Error! Reference source not found. Table 5.4.41shows details for the condenser fan motor design option. The motor efficiency leve ls listed were taken from American National Standards Institute (ANSI)/ARI Standard 1200-2006, “Performance Rating of Commercial Refrigerated Display Merchandisers and Storage Cabinets,” as DOE assumed that these types of motors were similar in efficiency. Because conde nser fan motors are outside the refrigerated space, efficiency improvements only impact the direct electrical consumption of the motors and

not the heat load.

Table 5.4.41 Details for "Condens er Fan Motor" Design Option

Code Description Rated Power (HP) Actual Power (W) Efficiency Cost

PSC Permanent Split Capacitor 1/6 428 29% $35.58

ECM Brushless DC Motor 1/6 188 66% $71.29



### 5.4.5.4 Evaporator and Condenser Fan Blades

High efficiency fan blades reduce motor sh aft power requirements by moving air more efficiently. Most evaporator and condenser fans use stamped sheet meta l or plastic axial fan blades that are paddle-shaped. These fan blades are lightweight and inexpensive. The blades are typically supplied by a fan blade manufacturer and mounted to the motor by the equipment manufacturer. The higher efficiency blades DOE considered typically have swept fins for improved airflow. DOE estimated that these fan blades could increase fan efficiency by 15

5-36

### percent for the evaporator and condenser fans. Th is efficiency improvement is realized as lower energy consumption by the fan motor.

Figure 5.4.3 Examples of Standard Fan Blades viii ix



### ,

Figure 5.4.4 Examples of High Efficiency Fan Blades x



### , xi



### Table 5.4.42 Details for “High Efficiency Fa n Blades – Evaporat or” Design Option

Code Description Fan Power Multiplier Cost Premium per Fan

EB1 Baseline 1 $­

EB2 Improved 0.85 $28.01



### Table 5.4.43 Details for “High Efficiency Fa n Blades – Condens er” Design Option

Code Description Fan Power Multiplier Cost Premium per Fan

CB1 Baseline 1 $­

CB2 Improved 0.85 $18.27



### 5.4.5.5 Evaporator Coil

Similar to the condenser coil, DOE considered two technology levels for the evaporator: a standard coil and a larger coil that was sized to run at a saturated evaporator temperature (SET) (also known as saturated suction te mperature, or SST) that is warmer than that of the baseline coil. DOE calculated the temperature difference (TD) between the SET and the walk-in’s

5-37

### interior temperature, for the baseline coil. Then DOE considered a theoretical improved coil that ran at an SET that was 2 degrees warmer than that of a baseline coil. DOE chose a relatively small change in SET because the TD can drastically affect the humidity inside the walk-in. This could result in a decrease in utility for some walk-i ns because of the nature of the product stored. For instance, fruits and flowers must be stored at a certain humidity in order to keep them fresh and not overdry them. In consultation with expert s, DOE determined that a TD change of only 2 degrees would not be enough to drastically change the humidity, but would be significant enough to result in energy savings.

As with the condenser coil, DOE used the heat transfer equation to calculate the size of the improved coil from the baseline coil, assuming all other characteristics stayed the same. DOE calculated the new area assuming that both the length and the width of the coil would change at the same rate. DOE then used the cost model to calculate the added cost of materials to produce the larger coil. Because compressor capacity and power consumption are directly related to SET, reductions in the energy consumption are realized through an improved normalized energy consumption. Details of the TD are shown in Table 5.4.44.

Table 5.4.44 Details for "Evapor ator Coil" Design Option

Code Description TD Reduction (°F)

EV1 Baseline 0

EV2 Improved 2



### As with condenser coils, for improved eva porator coils, DOE assessed the incremental

increase in cost due to additional material costand separately evaluated the impact on shipping cost for each equipment class and size . The results are shown in Table 5.4.45.

Table 5.4.45 Details for "Evaporator Coil" Design Option, Continued

Equipment Class Extra Material/Labor Cost ($) Extra Shipping Cost ($)

DC.M.I – Small $38.81 $4.03 DC.M.I – Large $51.02 $5.63

DC.M.O – Small $27.00 $2.80 DC.M.O – Large $36.53 $4.03

RC.M – Small $13.56 $1.45 RC.M – Large $26.96 $3.68

DC.L.I – Small $27.75 $2.25 DC.L.I – Large $27.80 $3.03

DC.L.O – Small $16.63 $1.65 DC.L.O – Large $20.94 $2.28

RC.L – Small $11.34 $1.30 RC.L – Large $23.11 $3.31



### 5.4.5.6 Evaporator Fan Control

Evaporator fan controls save energy by allo wing the evaporator fans to run at variable speed, or cycle on and off, during periods when the compressor is off. Without fan controls, the evaporator fans run at a constant speed at all times unless turned off manually. The proposed test procedure incorporates an off-cycle evaporator fan test to determine evaporator fan energy consumption during a compressor-off period. The propos ed test procedure measures the effect of

5-38

### any fan control, with the following constraint: “cont rols shall be adjusted so that the greater of a 25% duty cycle or the manufacturer default is used for measuring off-cycle fan energy. For variable-speed controls, the greater of 25% fan speed or the manufacturer’s default fan speed shall be used for measuring off-cycle fan energy. Wh en a cyclic control is used, at least three full ‘stir cycles’ are measured.” Because of these restrictions, the maximum energy savings that can be achieved is a 75% reduction in fan energy. DOE therefore set this as the energy savings achieved for the fan control technology option. Thes e savings are realized as a reduction in the off-cycle fan energy consumption, which reduces both the direct energy consumption of the system and the heat contribu tion that must be removed.

Table 5.4.46 Details for “Evaporator Fan Control” Design Option

Code Description Off-Cycle

Fan Power Multiplier Cost

Premium

EM1 Baseline 1 $­

EM2 Controlled 0.25 $300.00



### 5.4.5.7 Floating Head Pressure

The two technology levels for this design option are fixed head pressure and floating head pressure. Fixed head pre ssure involves keeping the compre ssor discharge pressure at a constantly fixed setting in order to enable operation over a variety of ambient temperatures in outdoor units. Generally, this is fixed at a high value in order to ensure that a sufficient amount of refrigerant can flow through the system, wh ich also protects the condenser against freezing and maintains the necessary pressu re difference across the expansi on valve. However, this also keeps the condensing temperature fixed at a high level regardless of the ambient temperature.

Floating head pressure utilizes a control system and sophisticat ed expansion valves, typically electronic expansion valves (EEVs), to control the flow of refrigerant and keep liquid refrigerant from reaching the compressor. A pr essure transducer may also be wired to the controller for pressure and temperature sensing. With floating head pressure, the compressor pressure and the saturated conde nsing temperature (SCT) float down to a minimum at which the compressor can operate. This typically corres ponds to an SCT of 70 degrees. Compressor capacity and power consumption are directly relate d to SCT; compressors run more efficiently at a lower SCT. Thus, reductions in the energy consumption due to floating head pressure are realized through improved normalized energy consumption.

Table 5.4.47 Details for “Floating Head Pressure” Design Option

Code Description Cost

Premium

- Fixed Head Pressure $­

FHP Floating Head Pressure $200.00



### 5.4.5.8 Defrost Controls

5-39

### Defrost cycle control can reduce energy consumption by reducing the frequency and duration of defrost periods. Mo st walk-in defrost systems wit hout controls are scheduled for certain times and last for a preset duration (time-time). Various control strategies includescheduling defrosts at certain times and using temperature termination control (timetemperature), only starting a defrost when necessary and then running for a set duration (temperature-time), and starting only when necessary and using temperature termination control (temperature-temperature). Still other strategies involve using an adaptive learning algorithm to predict when a defrost will be needed. Methods of detecting when a defrost is necessary and when a defrost cycle should terminate include opt ical sensing of frost on the evaporator coil or measurement of refrigerant temperature and pr essure at various points on the refrigeration equipment.

Due to the complexity of the various cont rol schemes, DOE did not attempt to analyze every one. However, in consultation with industry experts, DOE determined that without controls, most defrost cycles ar e scheduled to run more frequen tly and longer than necessary. Therefore, for the defrost control option, DOE as sumed that a control strategy would result in half the amount of defrost power required, implemented in the energy model as a reduction by half in the number of defrost cycles per day. Thes e savings are realized both as a reduction in the direct energy consumption of the system and a reduction in the amount of heat that must be removed by the system.

Table 5.4.48 Details for “Defrost Controls” Design Option

Code Description Cycle Divider Cost Premium

DF1 Baseline 1 $­

DF2 Controlled 2 $185.00



### 5.4.6 Baseline Specifications

DOE defined baseline specifications for each equipment class. These specifications include dimensions, numbers of components, te mperatures, nominal power ratings, and other case features that are necessary to calculate the energy consumption of each equipment class. In conjunction with the lowest tec hnological level of each design option, the baseline specifications define the energy consumption and cost of th e typical lowest efficiency equipment on the market. DOE established baseline specifications for each of the equipment classes modeled in the engineering analysis by reviewing available manufacturer data, selecting several representative units from available manufacturer data, and then aggregating the physical characteristics of the selected units. This pro cess created a representative unit for each equipment class with average characteristics for physical parameters (e.g., volume, wall area), and typical performance for energy-consuming component s. Table 5.4.49 through Table 5.4.52 show the specifications and units that are defined for envelopes and refrigeration systems, respectively.

5-40Table 5.4.49 Baseline Specifications for Envelopes, CoolersEquipment Class and SizeND.C -SmallND.C -MediumND.C -LargeD.C -SmallD.C -MediumD.C -LargeUnitsInternal Dry Bulb Temperature35.035.035.035.035.035.0FExternal Dry Bulb Temperature75.075.075.075.075.075.0FInternal RH0.60.60.60.60.60.6%External RH0.40.40.40.40.40.4%Height7.69.512.06.67.67.6ftLength10.012.025.06.010.280.0ftWidth8.020.030.06.07.015.0ftPassage Door Window Glass Area0.90.90.90.00.00.0ft2Display Door Width2.52.52.52.52.52.5ftDisplay Door Height6.36.36.36.36.36.3ftPassage Door Width3.03.03.03.03.03.0ftPassage Door Height7.07.07.07.07.07.0ftFreight Door Width7.07.07.07.07.07.0ftFreight Door Height9.09.012.09.09.012.0ftNumber of Display Doors0.00.00.03.08.050.0#Number of Passage Doors1.01.02.01.01.02.0#Number of Freight Doors0.01.01.00.00.00.0#Total External Surface Area433.01088.02820.0230.0404.23844.0ft2Floor Area80.0240.0750.036.071.41200.0ft2Total Passage Door Window Glass Area0.90.91.80.00.00.0ft2Non-Display Door Area21.084.0126.021.021.042.0ft2Total Display Door Area0.00.00.047.3126.0787.5ft2Total Passage Door Area21.021.042.021.021.042.0ft2Total Freight Door Area0.063.084.00.00.00.0ft2Walls, Ceiling & Non-Display Door Area332.0764.01944.0125.8185.81814.5ft2Case Gross Refrigerated Volume606.72280.09000.0237.0542.69120.0ft3Number of Light Tubes/Bulbs11341052#Number of Circulation Fans000000#Walls/Floor Baseline Cost$ 2,139$4,005$9,921$1,069$1,504$8,900$Total Display Door Baseline Cost$­$ ­$ ­$3,038$8,100$50,625$Total Baseline Cost$ 2,139$4,005$9,921$4,106$9,604$59,525$5-41Table 5.4.50 Baseline Specifications for Envelopes, FreezersEquipment Class and SizeND.F -SmallND.F -MediumND.F -LargeD.F -SmallD.F -MediumD.F -LargeUnitsInternal Dry Bulb Temperature-10.0-10.0-10.0-10.0-10.0-10.0FExternal Dry Bulb Temperature75.075.075.075.075.075.0FInternal RH0.60.60.60.60.60.6%External RH0.40.40.40.40.40.4%EER6.36.36.36.36.36.3Btu/W-hHeight7.69.512.06.67.67.6ftLength8.09.025.06.010.280.0ftWidth6.020.020.06.07.015.0ftPassage Door Window Glass Area0.90.90.90.00.00.0ft2Display Door Width2.52.52.52.52.52.5ftDisplay Door Height6.36.36.36.36.36.3ftPassage Door Width3.03.03.03.03.03.0ftPassage Door Height7.07.07.07.07.07.0ftFreight Door Width7.07.07.07.07.07.0ftFreight Door Height9.09.012.09.09.012.0ftNumber of Display Doors0.00.00.03.08.050.0#Number of Passage Doors1.01.02.01.01.02.0#Number of Freight Doors0.01.01.00.00.00.0#Total External Surface Area308.8911.02080.0230.0404.23844.0ft2Floor Area48.0180.0500.036.071.41200.0ft2Total Passage Door Window Glass Area0.90.91.80.00.00.0ft2Non-Display Door Area21.084.0126.021.021.042.0ft2Total Display Door Area0.00.00.047.3126.0787.5ft2Total Passage Door Area21.021.042.021.021.042.0ft2Total Freight Door Area0.063.084.00.00.00.0ft2Walls, Ceiling & Non-Display Door Area239.8647.01454.0125.8185.81814.5ft2Case Gross Refrigerated Volume364.81710.06000.0237.0542.69120.0ft3Number of Light Tubes/Bulbs1134952#Number of Circulation Fans000000#Walls/Floor Baseline Cost$ 2,111$5,053$11,118$1,373$1,982$16,394$Total Display Door Baseline Cost$­$ ­$ ­$3,375$9,000$56,250$Total Baseline Cost$ 2,111$5,053$11,118$4,748$10,982$72,644$5-42Table 5.4.51 Baseline Specifications for Refrigeration Systems, Medium TemperatureEquipment Class and SizeDC.M.I –SmallDC.M.I –LargeDC.M.O –SmallDC.M.O –LargeMC.M –SmallMC.M –LargeInteriorTemperature[F]353535353535Saturated Evaporator Temperature (SET) Nominal [F]252525252525Saturated Condenser Temperature (SCT) Nominal [F]115115115115--Design Ambient Temperature [F]90909595--Nominal Evaporator Coil Capacity [Btu/h]15,60026,00015,60026,0009,70031,200Evaporator Coil Height [in]12.512.512.512.513.512.5Evaporator Coil Width [in]48.080.048.080.031.396.0Evaporator Coil Depth [in]444444Evaporator Fan TypeECMECMECMECMECMECMEvaporator Fan Horsepower [HP]1/151/151/151/151/151/15Number of Evaporator Fans [#]353526Condenser Coil Height [in]15.018.018.018.0--Condenser Coil Width [in]16.030.030.030.0--Condenser Coil Depth [in]3333--Condenser Fan TypePSCPSCPSCPSC--Condenser Fan Horsepower [HP]1/61/61/61/6--Number of Condenser Fans [#]1222--Nominal Compressor Capacity [Btu/h]15,00026,00015,00024,000--DefrostMechanismType------Defrost Time per Day [hrs]------Defrost+Drain Heater Power [W]------5-43Table 5.4.52 Baseline Specifications for Refrigeration Systems, Low TemperatureEquipment Class and SizeDC.L.I –SmallDC.L.I –LargeDC.L.O –SmallDC.L.O –LargeMC.L –SmallMC.L –LargeInteriorTemperature[F]-10-10-10-10-10-10Saturated Evaporator Temperature (SET) Nominal [F]-20-20-20-20-20-20Saturated Condenser Temperature (SCT) Nominal [F]110110110110--Design Ambient Temperature [F]90909595--Nominal Evaporator Coil Capacity [Btu/h]6,00012,0006,00012,0006,00024,000Evaporator Coil Height [in]13.512.513.512.513.512.5Evaporator Coil Width [in]31.948.031.948.031.996.0Evaporator Coil Depth [in]444444.25Evaporator Fan TypeECMECMECMECMECMECMEvaporator Fan Horsepower [HP]1/151/151/151/151/151/15Number of Evaporator Fans [#]232326Condenser Coil Height [in]15.018.018.018.0--Condenser Coil Width [in]16.030.030.030.0--Condenser Coil Depth [in]3333--Condenser Fan TypePSCPSCPSCPSC--Condenser Fan Horsepower [HP]1/61/61/61/6--Number of Condenser Fans [#]1212--Nominal Compressor Capacity [Btu/h]6,50012,5006,00011,500--Defrost Mechanism TypeELEELEELEELE--Defrost Time per Day [hrs]111111Defrost+Drain Heater Power [W]1,6562,7561,6562,7561,6565,4565-44

### 5.4.7 Non-Numerical Assumptions

In developing the energy consumption model, DOE made certain non-numerical assumptions concerning the analysis. These include general assumptions about the analysis as well as specific assumptions regarding load components and design options.

5.4.7.1 Assumptions Concerning the Envelope Energy Calculations

The temperature and humidity inside the cooled space of the WICF and of the surrounding environment was considered to be constant. While a real walk -in envelope sited in the outdoors may consume more or less energy re lative to a walk-in sited indoors, this was ignored in the engineering analysis for two reasons. First, the WICF test procedure does not account for weather effects. It compares the pe rformance of all walk-ins, designed for both the indoors and outdoors, in the same manner. Secondly, accounting for large regional variation in

weather would result in a variable standard that un dermines the “level playing field” that DOE is attempting to protect.

The cooled space of the walk-in was modele d as an empty space. No accounting for food (or other) product variation, such as type of product, rate of product tur nover or product initial temperature was considered. Therefore the heat capacity (or thermal mass) nor the volume of stored products was considered which would have otherwise impacted air movement, total cooled air volume and transient temperatures of the cooled space. This was to eliminate confounding factors so that design options could be compared within the engineering analysis. (However, product loading was considered in the Energy Use Analysis (chapter 7 of the preliminary TSD) to better replicate real-world conditions.)

If air curtains were selected as a design option in the analysis, it was assumed that the device would only operate for as long as a door th at it was protecting was opened. Therefore, the door opening time exactly equals the air curtai n fan motor operation time. This was used to calculate the associated electrical energy consumed to reduce air exchange. The majority of commercially available air curtains, considered by the DOE, include electronic switches that sense door openings as a standard option.

All of the components were modeled as newly manufactured. Wear on gaskets, joints etc were not considered. Foam R-value degradation caused by water infiltration was not considered. However, DOE used long term thermal resistance (LTTR) values of both XPS and PU foam for

all of the heat conduction calculations. This refl ects the use of an LTTR measurement in DOE’s proposed test procedure for WICF.

In previous related rulings, vacuum insulate d panels have not been considered viable design options. However, due to recent increa se in production, corresponding drop in cost and efforts by VIP manufacturers to break into the wa lk-in market by making a product that is better suited for panel construction, DOE considered VIPs as a design option. While they are still far more expensive than other options, DOE recogn izes that they are technically viable and

commercial available for use in WICF.

5-45

### The walk-ins were modeled as simple cuboi ds. No unique geometries were considered such as L-shaped systems or other designs that have irregular external surface area to volume ratios. Due to the variation in design, various geometries would have made the analysis too complex. In addition, co-sited walk-ins or walk-i ns that share a wall with another walk-in were not considered, again due to the vast variati on in design. DOE considers the impact of this approach to be limited because the key paramete r considered in the analysis was the total external surface area which is most strongly correlated with WICF energy consumption.

Radiation heat transfer was not directly c onsidered in the energy modeling of WICF.

Since outdoor conditions were not considered an d it was assumed that WICF are not normally sited near high temperature radiative heat sources such as boilers or other high heat equipment, this is a reasonable assumption. However, radia tion is indirectly considered in the U-value

calculations used to measure the performance of glass display doors. The Window 5.2 software models this form of heat transfer which is largely reduced by low emissivity coatings.

While in practice, the frequency of door op ening events would vary depending on the time of day and walk-in type, DOE considered th e door openings to occur at regular intervals throughout a twenty-four hour period. This simplif ying assumption ignores the transient effects of air infiltration on internal temperature of the walk-in among other transient phenomena. Because all walk-ins within a product class were compared using the same assumptions, this was considered a reasonable simplification. In additio n, the overall impact on daily or annual energy consumption is believed to be limited and these assumptions reflect the values of the proposed WICF test procedure. 75 FR 197

5.4.7.2 Assumptions Concerning the Refrigeration Energy Consumption

DOE assumed that all conditions are base d on new equipment tested in a controlledenvironment chamber subjected to AHRI 1250-2009, the proposed refrigeration test procedure. Once the test procedure is finalized, manufacturers that certify their equipment to comply with Federal standards will be required to test new units to this test method, which specifies certain ambient temperature, humidity, and other requirements.

DOE did not consider hot-gas defrost as a design option for defrost mechanisms in multiplex condensing systems (see chapter 4, screen ing analysis). During hot-gas defrost, hot refrigerant from the compressor rack bypasses the condenser and expans ion device and is piped directly to the evaporator coil, melting the frost on the coil. The test procedure does not capture the heat added to a walk-in during a hot-gas defros t cycle. Therefore, DOE did not consider this technique.

Due to the ongoing phaseout of HCFC refrigerants in the WICF industry, HFC refrigerants are most likely to be used in this equipment in the future. Other alternative refrigerants, such as ammonia, hydrocarbons, and CO 2 

### , were not considered in this analysis, as they are not currently used in domestically manufactured WICF refrigeration systems. Additionally, some of these refrigerants, including ammonia, could be limited by State and local building codes due to toxicity concerns. Common HFC refrigerants used in refrigeration equipment include R-507 and R- 404A. DOE assumed that only HFC refrigerants will be utilized

5-46

### by WICF refrigeration systems and has based its analysis solely upon equipment containing those refrigerants.

DOE assumed that there are no cyclic losses associated with the refrigeration system operation. In steady state operation, the majority of the refrigerant charge is located in the high pressure side of the system. During an off-cycle, the refrigerant migrates to the evaporator, because the evaporator is at a lower pressure than the condenser. At the start of the next operating cycle, the excess refrigerant charge in the low side of the system must be transferred to the high side of the system to achieve steady state operation. Liquid refrigerant in the evaporator flows to the accumulator, the suction pressure drops to a value low enough to vaporize the liquid, and the compressor pumps the vapor to the conden ser. This process can take several minutes, during which time the refrigeration system does not operate at steady state capacity. The cyclic losses are greater in systems having larger coil sizes as a result of the greater amount of refrigerant charge in such systems. Any However, because the proposed test procedure only measures the compressor energy consumption when the compressor is running at steady state,

these losses are not accounted for.

In the baseline, the head pressure of the system is fixed at a high value regardless of the external temperature, in order to ensure that a sufficient amount of refrigerant can flow through the system, which also protects the condenser against freezing and maintains the necessary pressure difference across the expansion valve. One of the design options is implementing floating head pressure, in which the refrigerant flow is dynamically controlled over a broad range of external temperatures. In this case, condensing temperatures lower than the temperatures of 90 or 95 degrees necessary for a fixed-head pressure system can be utilized. However, DOE

assumed that the limit to which the condensin g temperature could float is 70 degrees. Compressor performance maps do not typically show data at condensing temperatures beyond 70 degrees, and compressor performance is not guaranteed at lower temperatures. Furthermore, DOE assumed that for systems with floating h ead pressure, as the condensing temperature decreased with the ambient temperature, the temperature difference (TD) between the condensing and ambient temper ature would stay the same.

5.4.8 Numerical Constants and Assumptions

5-47

### Table 5.4.53 Envelope Assumptions

Parameter Value Units Source
External Dry Bulb Temperature 75 F Assumed Cooler- Internal Dry Bulb Temperature 35 F Standard medium-temperature set-point, WICF

Manufacturers Concrete Floor temperature, Cooler 60 F DOE WICF Proposed Test Procedure NOPR Concrete Floor temperature, Freezer 65 F DOE WICF Proposed Test Procedure NOPR
Freezer- Internal Dry Bulb Temperature -10 F Standard low-temperature set-point, WICF

Manufacturers

Internal RH 60% % Assumed

External RH 40% % Population weighted national average humidity, DOE analysis

Cooler-EER 12.4 Btu/W-h Energy Efficiency Ratio based on AHRI Refrigeration Equipment Test Procedure

Freezer-EER 6.3 Btu/W-h Energy Efficiency Ratio based on AHRI Refrigeration Equipment Test Procedure
Daily Time Period 24 h Assumed
Acceleration of Gravity 32.2 ft/s 2 Assumed

LTTR-XPS 5.61 ft 2 -F-h/Btu As tested by a third party laboratory
LTTR-Polyurethane (Foam-inplace@ 2.4 lb/ft 3 density) 6.20 ft 2 -F-h/Btu As tested by a third party laboratory

External Equivalent Convective

Film Coefficient 0.68 ft 2 -F-h/Btu Assumed

Internal Equivalent Convective Film

Coefficient 0.25 ft 2 -F-h/Btu Assumed

Floor Equivalent Convective Film

Coefficient 0.87 ft 2 -F-h/Btu Based on Finite Element Heat Transfer Model, DOE Analysis Rated power, 2-way pressure air

freezer relief valve heater 23 W Component Manufacturer Data

2-way pressure air relief valve heater, Operation per day 24 h Component Manufacturer Data

Average Shipping Distance to

Distribution Center 1000 miles DOE Estimate

Door Flow Factor 0.8

- ASHRAE Fundamentals
Display Door Width 2.5 ft Assumed
Display Door Height 6.3 ft Assumed
Passage Door Width 3 ft Assumed
Passage Door Height 7 ft Assumed
Freight Door Width 7 ft Assumed
Freight Door Height 9 ft Assumed
Large Freight Door Width 7 ft Assumed
Large Freight Door Height 12 ft Assumed

Infiltration Parameters
Display Doors
Door Openings Per Day, P 72 # DOE WICF Proposed Test Procedure NOPR
Door Open/Close Time 8 seconds DOE WICF Proposed Test Procedure NOPR
Time Door Stands Open 0 min/day DOE WICF Proposed Test Procedure NOPR
Passage Doors
Door Openings Per Day, P 60 # DOE WICF Proposed Test Procedure NOPR
Door Open/Close Time 12 seconds DOE WICF Proposed Test Procedure NOPR
Time Door Stands Open 15 min/day DOE WICF Proposed Test Procedure NOPR

5-48Freight Doors
Door Openings Per Day, P 60 # DOE WICF Proposed Test Procedure NOPR
Door Open/Close Time 12 seconds DOE WICF Proposed Test Procedure NOPR
Time Door Stands Open 15 min/day DOE WICF Proposed Test Procedure NOPR

Anti-sweat power, with display door option DR2 1.0 W/ft DOE Estimate

Anti-sweat power, with display door option DR3 or higher 0.0 W/ft DOE Estimate

Percentage of anti-sweat heat

transferred into the walk-in 70 % DOE Estimate

Freezer Passage Door Heat Wire Operation Time Per Day 24 h Assumed

Control System Average Power 5 W Assumed
Manufacturer Selling Price Mark-up 1.39

- Assumed



### Table 5.4.54 Refrigeration System Assumptions Associated with Defrost

Constants Specified by the Test Procedure Value Units Source

Infiltration coefficient k13 0.0001 cf m-hr/Btu Proposed Test Procedure

Infiltration coefficient k14 3.49 cfm Proposed Test Procedure Humidity ratio of incoming air 0.0105 lb water/lb air Proposed Test Procedure Density of incoming air 0.073 lb/ft^3 Proposed Test Procedure Physical Properties of Materials

Specific heat of ice 0.487 Btu/lb-R ASHRAE Handbook of Fundamentals, 2009

Specific heat of water 1.00 Btu/lb-R ASHRAE Handbook of

Fundamentals

Latent heat of fusion of water 143.5 Btu/lb ASHRAE Handbook of

Fundamentals

Meltwater temperature 32 F ASHRAE Handbook of Fundamentals, 2009 Other Assumptions Length of defrost 15 min DOE Assumption

Amount of time between defrosts 6 h DOE Assumption



### Table 5.4.55 Refrigeration Syst em Baseline TD Assumptions

Class Ambient (°F) Baseline SCT (°F) Baseline TD (°F)

DC.M.I 90 115 25

DC.L.I 90 110 20

DC.M.O 95 115 20

DC.L.O 95 110 10



### 5.4.9 Model Components: Envelope

Figure 5.4.5 shows the components of the energy consumption model used in the engineering analysis. The model calculates energy consumption in two major subsections, heat load and electrical energy consumption, wh ich are further broken out by the underlying components or physics.

5-49Daily Energy Consumption

[kWh/day]

Total Heat Load

[kWh/day]

EER

Electric Energy Consumption

[kWh/day]

Heat Load

[Btu/h] Legend: Component

Energy Consumption

[kWh/day]

Lighting Energy Consumption

[kWh/day] Anti-Sweat

Energy Consumption

[kWh/day]

Component
Load [Btu/h]

Conduction
Load [Btu/h] Anti-Sweat
Heat Load

[Btu/h] Lighting Heat
Load [Btu/h] Non-Electric
Load [Btu/h] Total Heat

Load [Btu/h]

Door Opening
Infiltration Load [Btu/h] Steady-State
Infiltration Load [Btu/h] Other Energy Consumption

[kWh/day]

Other Heat

Load [Btu/h]



### Figure 5.4.5 Overview of Envelope Engineering Analysis Calculations

5.4.9.1 Heat Conduction Load

The heat transfer via conduction in the engineering analysis is broken into non-glass and glass related conduction. Non-gl ass includes the typical insula ted walls, ceiling, floors and nontransparent doors. The glass calculations cover display door glass and glass inset windows. The heat transfer, in Btu/h, is calculated for each of these components based on the temperature differential between the cooled space and the surro undings, the thermal resistance of the material

i.e. R-value of foam or the U-value of glass, a nd the associated surface area of that component or components. These properties change based on the cu rrent design option level. For example, four inch foam panel versus six inch foam panel.

After completing these calculations, the total load is summed and then converted into units of kWh/day utilizing the assumed Energy Efficiency Ratio (EER). The EER value corresponds to the current walk-in type being analyz ed (freezer or cooler). Further clarification

of the use of an EER is described below.

5.4.9.2 Energy Efficiency Ratio (EER)

In order to estimate the associated refrigeration equipment energy consumption due to the envelope energy losses, DOE implemented th e use of refrigeration equipment EER. The EER represents the energy performance of the refrige ration equipment as a ratio of units of thermal energy removed from the conditioned walk-in space to units of electrical en ergy input (to operate refrigeration compressors, fans etc). Therefore, this ratio represents the efficiency of the refrigeration equipment. DOE assumed two differ ent EER values that correspond to medium and

5-50

### low temperature refrigeration systems of 12.4 Btu/W-h and 6.3 Btu/W-h xii 

### , respectively. Depending on the temperature being analyzed, the envelope engineering analysis model selects the appropriate EER to convert the thermal ener gy into units of electrical energy used.

This “conversion” helps the load due to th e envelope be more easily understood. With units of thermal energy in kWh, the thermal load could be directly summed with the kWh due to use of lights, anti-sweat heaters and other electri cal components. The result is the total energy consumption per day in kWh.

5.4.9.3 Infiltration Load: Steady-State

The amount of embodied energy in an air sample is primarily a function of its temperature (and therefore density). This property is typically referred to as the enthalpy in any thermodynamic system (such as a walk-in cooler or freezer). The required amount of energy needed to remove heat from the air is calculated as the difference between the enthalpy of air entering the refrigerated space and enthalpy of the air inside the refrigerated space. This calculation is commonly used when designing walk -ins and typically uses dry-bulb and wet-bulb temperatures. In the engineering analysis the di fference between the infiltrating and exfiltrating air, per unit cubic foot, is calculated using th e functional relationship between temperature and enthalpy.

Then using the estimated infiltration rate per unit surface area of the walk-in the thermal energy consumption, in units of Btu/h, is direct ly calculated. As with the conduction load, this thermal energy is converted into units of kWh/day using the appropriate EER value.

5.4.9.4 Infiltration Load : Door Opening

The heat load due to door openings is calcu lated in an identical manner as the steadystate infiltration calculations using the enthalpy difference of the exchanged air. In order to calculate the volume of air exchanged per door opening, DOE used equations developed by

ASHRAE xiii 

### . With known air properties, door geomet ry and assumptions about door opening frequency, duration, the number of doors and the e ffectiveness of infiltrat ion reduction devices, the volume of air exchanged for each unique doo r opening event is computed. The assumptions change with various design options. For example, the infiltration reduction effectiveness changes depending if a strip curtain or ai r curtain is in place or a disp lay door is being opened versus a large freight door. As for other thermal energy ca lculations the total load in Btu/h is then converted into kWh/day using the EER.

5.4.9.5 Anti-Sweat and Other Heater Wire Electrical Load

Resistive heater wire is rated in units of W/ft. For a given door the perimeter length is calculated and multiplied by the wire rating to compute the total electrical load per door. The amount of time per day that the wire is powered is calculated using the assumed percent time off (PTO) if an anti-sweat controller is selected or not . In addition the rated power of the heater wire changes based on the design option level of th e display door. With total wattage and operation time per day, the total kWh/day is then directly calculated.

5-51

### 5.4.9.6 Lighting Electrical Load

The lighting electrical load is calculated in an identical manner as the anti-sweat systems. Using the rated power of the light and assump tions about PTO based on the current control system design option, the kWh/day from lights is computed.

5.4.9.7 Other Electrical Devices

As with the previous devices, the device ra ted power such as the heated by-directional pressure relief valve used in walk-in freezers or the power use of the control system hardware is multiplied by the hours of use per day to get the total kWh/day consumption.

5.4.9.8 Additional Heat Load Due to Electrical Device Waste Heat

Using the total energy consumption of all electrical devices sited inside the walk-in (air curtain power, for example, is not included because they are mounted external to the refrigerated space of the walk-in) an associated additional h eat load is calculated. This thermal load is converted using the EER into an effective extr a compressor load due to the operation of these

electrical devices.

The energy consumption attributed to all components is totaled to compute the full product incremental energy consumptions for up to fifteen unique design option levels. The incremental cost of each design option is also to taled in order to plot th e cost-efficiency curves for each product class and size analysis point (small, medium and large). The final costefficiency curve displays the design options ordered by relative cost-effectiveness.

5.4.10 Model Components: Refrigeration

The energy consumption model analytically calculates energy consumption using the same methodology as the proposed test proce dure. In the proposed test procedure, the refrigeration system is tested under certain conditions to dete rmine steady state capacity and power. Then an assumed non-refriger ation load attributed to the envelope is calculated. This methodology assumes that the refrigeration system is sized to the expected load, allowing refrigeration systems to be compared with each other even when the tester does not know the characteristics of the envelope with which the refrigeration system will ultimately be paired. From the steady state power, the capacity, and the expected load profile, the annual energy consumption can be calculated.

DOE’s ultimate metric that it chose for expressing the performance of the refrigeration system is normalized energy consumption; that is, the total annual energy consumption divided by the net capacity of the system. DOE chose to measure normalized energy consumption instead of total energy consumption because th e annual energy consumption depends partly on the capacity of the system, which is used to determine the load factors or duty cycles. Some design options increase the capacity, which w ould tend to reduce the energy consumption by allowing lower duty cycles. However, under the propos ed test procedure, a system with a higher capacity would be assumed to have a larger non-refrigeration envelope load, which could increase the duty cycle. To account for these co mpeting effects, DOE normalized the energy

5-52

### consumption by capacity. This rewards the design options that increase the efficiency of the refrigeration system: not the ones that save more ne t energy, but the ones that save more energy

for their size.

Error! Reference source not found. Figure 5.4.6 presents a schematic showing the components in the energy consumption model for dedicated condensing systems. For indoor systems, the test procedure assumes that the ambient temperature does not change, and therefore the energy consumption does not change from day to day. In this case, the energy consumption per day is multiplied by 365 to get annual energy consumption. For outdoor systems, a yearly temperature profile is assumed by the proposed test procedure, which lists the number of hours in each temperature “bin,” a range of 5 degrees. In this case, the net capacity and system power are tested at 3 test temperatures, and then calculated for all the other temperature bins using linear interpolation. Then the annual energy consum ption is calculated by summing the energy consumption for each temperature bin multiplied by the number of hours in the bin.

Normalized Energy

Consumption ((MWh/year)/(kBtu/h))

Net Capacity (Btu/h)

Gross Capacity (Btu/h)

On

‐ Cycle Evaporator Fan

Motor Heat Load (Btu/h) Energy Consumption (Wh/year)

On

‐ Cycle System Power (W)

Compressor Power (W)

On

‐ Cycle Evaporator Fan

Power (W)

Condenser Fan Power (W) Off

‐ Cycle Evaporator Fan

Power (W) Defrost Power (W) Load Factors

Non

‐ Refrigeration Load (Btu/h)

Off

‐ Cycle Evaporator Fan

Heat Load (Btu/h)

Defrost Heat Load (Btu/h)

Net Capacity (Btu/h)



### Figure 5.4.6 Energy Consumption Model for Dedicated Condensing Systems

5-53

### 5.4.10.1 Net Capacity

The net capacity is calculated as the gross capacity of the compressor, less the heat given off by the evaporator fans when the compresso r is running. Defrost heat is not considered because it is measured with a separate test, and would not be accounted for in the test procedure during the test of net capacity. The gross compressor capacity is calculated by using the compressor model described in section 6.4 of ARI Standard 540-2004 (ARI 540), Performance Rating of Positive Displacement Refrigerant Compressors and Compressor Units . This model is based on a 10-coefficient polynomial derived fro m empirical compressor performance data for capacity, power, mass flow, current, and efficiency. The coefficients are derived for each of these parameters as a function of SET and SCT. Compressor coefficients, or tabulated empirical data (from which coefficients can be derived), are available from compressor manufacturers. The gross capacity is determined from the published coefficients, the SET, and the SCT.

5.4.10.2 On-Cycle System Power

The on-cycle system power is the sum of the compressor power, the on-cycle evaporator fan power, and the condenser fan power. Simila r to the capacity, the compressor power is determined from the published compressor coefficients, the SET, and the SCT.

5.4.10.3 Load Factors

The load factors represent the fraction of the time that the compressor is running at both a “high load” period and a “low load” period. The high-load period corresponds to the time during the day when the walk-in experiences a high heat load due to product being stored in the walk-in, employees entering and leaving, etc. The low-load period corresponds to the time during the day when the walk-in is not being ac cessed, and experiences a low heat load: night, off-business hours, etc. Per the proposed test procedure, 1/3 of the time is experienced at a high load and 2/3 at a low load. The corresponding load factors, LFH (load factor at high load) and LFL (load factor at low load) are calculated from the heat load on the walk-in at a high and low period respectively (including non-refrigeration heat load, evaporator fan heat load, and defrost heat load), and the net capacity of the refrigeration system to reject this load. This determines how frequently the compressor must run at a high and low period.

(if

, ) 

### Eq. 5.2

(if

, ) 

### Eq. 5.3

where: WLH is the heat load on the walk-in at a high period WLL is the heat load on the walk-in at a low period

q ss 

### is the net capacity.

5-54

### WLH and WLL include all heat loads on the walk-in: non-refrigeration heat load, evaporator fan heat load, and defrost heat load:

Eq.5.4

Eq.5.5

where: BLH and BLL are the non-refrigeration heat load at a high and low period, respectively,

EF comp,off 

### is the evaporator fan motor power in W (multiplied by 3.412 Btu/h/W to get heat load, Q df 

### is the defrost heat load.

(The on-cycle evaporator fan motor heat is not included in this equation because it is already accounted for in the net capacity.)

The non-refrigeration heat loads are derive d from the net capacity and, for outdoor units, an assumed temperature profile. As discussed above, this is because the methodology assumes that the refrigeration system is sized to the exp ected load, allowing refrigeration systems to be compared with each other even when the tester does not know the characteristics of the envelope that the refrigeration system will ultimately be paired with.

Figure 5.4.7 presents a schematic showing the components in the energy consumption model for unit coolers connected to multiplex condensing systems. The model is similar, except the power attributed to the unit cooler is calculated by assuming a certain efficiency, or EER, for the multiplex system. In this case, the EER is a ssumed to be constant throughout the year, so energy consumption per day is multiplied by 365 to get annual energy consumption.

The default EER values are contained in the proposed test procedure. The test procedure provides tables of EER values for both medium and low temperature systems. The EER values are expressed in Btu/Wh, as a function of adjusted dew point temperature. The test procedure provides that the adjusted dew point temperatur e for a medium temperature system shall be 19  ̊ F

and shall -26  ̊ F for a low temperature system, unless the unit cooler is rated at a suction dew point other than 19  ̊ F for a refrigerator or -26  ̊ F for a freezer, in which case the adjusted dew point value shall be 2  ̊ F less than the unit cooler rating suction dew point. (cite)

5-55Normalized Energy Consumption ((MWh/year)/(kBtu/h))

Net Coil

Capacity (Btu/h)

Gross Coil Capacity (Btu/h) Energy Consumption (Wh/year)

On

‐ Cycle System

Power (W) Off

‐ Cycle Evaporator

Fan Power (W) Defrost Power (W) Load Factors

On

‐ Cycle Evaporator

Fan Motor Heat Load (Btu/h) Net Coil Capacity

(Btu/h)

On

‐ Cycle Evaporator

Fan Heat Load (Btu/h)

On

‐ Cycle Evaporator

Fan Power (W)

EER of Multiplex

System Non

‐ Refrigeration

Load (Btu/h)

Off

‐ Cycle Evaporator

Fan Heat Load (Btu/h)

Defrost Heat Load (Btu/h)

Net Capacity (Btu/h)



### Figure 5.4.7 Energy Consumption Model for Unit Coolers Connect ed to Multiplex Condensing Systems

5.5 COST-EFFICIENCY CURVES

Below are the cost-efficiency curves for the envelope and refrigeration equipment, respectively.

As explained in section 5.4.10, DOE’s ultimate metric that it chose for expressing the performance of the refrigeration system is normaliz ed energy consumption; that is, the total annual energy consumption divided by the net capacity of the system. Likewise, DOE divided the price by the net capacity at each efficiency level. One notable observation for some equipment classes is that for a few efficiency levels above the baseline, the estimated cost per unit energy consumption appears to decrease. This indicates that for these efficiency levels, although the absolute price of the unit increases, the capacity also increases at a faster rate, so the price per capacity decreases.

5-56

### 5.5.1 Envelope Cost-Efficiency Curves Table 5.5.1 Cost-Efficiency Data fo r the ND.C. Small Equipment Class

Efficiency

Level Daily
Energy

Use [kWh/day] MPC
Mfg.

Cost

[$] MSP
Mfg.

Price

[$] Design
Option

L0 5.18 $2,224 $3,358 Baseline

L1 2.99 $2,315 $3,484 L0 + SC

L2 2.74 $2,349 $3,531 L1 + LED

L3 1.91 $2,600 $3,940 L2 + FLR2

L4 1.81 $2,673 $4,054 L3 + TCK2

L5 1.80 $2,682 $4,067 L4 + XC

L6 1.68 $2,792 $4,237 L5 + TCK3

L7 1.64 $2,841 $4,309 L6 + FLR3

L8 1.49 $3,033 $4,607 L7 + TCK4

L9 1.39 $3,226 $4,904 L8 + TCK5

L10 1.15 $4,226 $6,294 L9 + VEST

L11 0.96 $6,224 $8,921 L10 + INSH1

L12 0.87 $7,345 $10,479 L11 + VIP

L13 0.83 $7,869 $11,206 L12 + ATG

$0 $2,000 $4,000 $6,000 $8,000 $10,000 $12,000

0.0 2.0 4.0 6.0Manufacturer Selling Price [$]

Daily Energy Consumption [kWh/day]



### Figure 5.5.1 Cost-Efficiency Cu rve for the ND.C. Equipmen t Class [Small, Number of Doors: Display, Passage, and Freight (0,1,0)]

5-57

### Table 5.5.2 Cost-Efficiency Data for the ND.C. Medium Equipment Class

Efficiency

Level Daily
Energy

Use [kWh/day] MPC
Mfg.

Cost

[$] MSP
Mfg.

Price

[$] Design
Option

L0 11.50 $4,164 $6,476 Baseline

L1 6.13 $4,527 $6,981 L0 + SC

L2 5.88 $4,561 $7,028 L1 + LED

L3 5.85 $4,576 $7,049 L2 + XC

L4 4.38 $5,330 $8,291 L3 + FLR2

L5 4.14 $5,498 $8,551 L4 + TCK2

L6 3.86 $5,750 $8,941 L5 + TCK3

L7 3.73 $5,896 $9,159 L6 + FLR3

L8 3.38 $6,339 $9,841 L7 + TCK4

L9 3.13 $6,782 $10,523 L8 + TCK5

L10 2.55 $8,782 $13,303 L9 + VEST

L11 2.10 $13,381 $19,361 L10 + INSH1

L12 1.87 $15,961 $22,947 L11 + VIP

L13 1.76 $17,285 $24,788 L12 + ATG

$0 $5,000 $10,000 $15,000 $20,000 $25,000 $30,000

0.0 5.0 10.0 15.0Manufacturer Selling Price [$]

Daily Energy Consumption [kWh/day]



### Figure 5.5.2 Cost-Efficiency Cu rve for the ND.C. Equipment Class [Medium, Number of Doors: Display, Passage, and Freight (0,1,1)]

5-58

### Table 5.5.3 Cost-Efficiency Data for the ND.C. Large Equipment Class

Efficiency

Level Daily
Energy

Use [kWh/day] MPC
Mfg.

Cost

[$] MSP
Mfg.

Price

[$] Design
Option

L0 23.55 $10,316 $16,069 Baseline

L1 14.27 $10,862 $16,827 L0 + SC

L2 13.53 $10,962 $16,967 L1 + LED

L3 13.45 $10,986 $17,000 L2 + XC

L4 12.88 $11,414 $17,655 L3 + TCK2

L5 12.19 $12,056 $18,637 L4 + TCK3

L6 9.80 $14,411 $22,541 L5 + FLR2

L7 9.42 $14,868 $23,227 L6 + FLR3

L8 9.22 $15,118 $23,574 L7 + CS2

L9 8.36 $16,246 $25,296 L8 + TCK4

L10 7.74 $17,373 $27,017 L9 + TCK5

L11 7.67 $17,573 $27,295 L10 + CS3

L12 6.73 $20,573 $31,465 L11 + VEST

L13 6.28 $24,020 $36,257 L12 + ATG

L14 5.18 $35,722 $51,745 L13 + INSH1

L15 4.62 $42,285 $60,868 L14 + VIP

$0 $10,000 $20,000 $30,000 $40,000 $50,000 $60,000 $70,000

0.0 5.0 10.0 15.0 20.0 25.0Manufacturer Selling Price [$]

Daily Energy Consumption [kWh/day]



### Figure 5.5.3 Cost-Efficiency Cu rve for the ND.C. Equipmen t Class [Large, Number of Doors: Display, Passage, and Freight (0,2,1)]

5-59

### Table 5.5.4 Cost-Efficiency Data fo r the D.C. Small Equipment Class

Efficiency

Level Daily
Energy

Use [kWh/day] MPC
Mfg.

Cost

[$] MSP
Mfg.

Price

[$] Design
Option

L0 34.65 $4,248 $6,036 Baseline

L1 28.53 $4,348 $6,175 L0 +

ASCTRL

L2 23.40 $4,708 $6,675 L1 + LED

L3 19.56 $5,004 $7,086 L2 + SC

L4 13.69 $6,168 $8,704 L3 + DR2

L5 8.56 $7,204 $10,144 L4 + DR3

L6 8.03 $7,317 $10,326 L5 + FLR2

L7 7.16 $7,567 $10,673 L6 + CS2

L8 7.12 $7,595 $10,719 L7 + TCK2

L9 7.07 $7,636 $10,787 L8 + TCK3

L10 5.44 $9,206 $12,969 L9 + DR4

L11 5.43 $9,212 $12,978 L10 + XC

L12 5.41 $9,234 $13,010 L11 + FLR3

L13 5.35 $9,307 $13,129 L12 + TCK4

L14 5.31 $9,380 $13,249 L13 + TCK5

L15 5.23 $10,137 $14,210 L14 + INSH1

$0 $2,000 $4,000 $6,000 $8,000 $10,000 $12,000 $14,000 $16,000

0.0 10.0 20.0 30.0 40.0Manufacturer Selling Price [$]

Daily Energy Consumption [kWh/day]



### Figure 5.5.4 Cost-Efficiency Cu rve for the D.C. Equipmen t Class [Small, Number of Doors: Display, Passage, and Freight (3,1,0)]

5-60

### Table 5.5.5 Cost-Efficiency Data fo r the D.C. Medium Equipment Class

Efficiency

Level Daily
Energy

Use [kWh/day] MPC
Mfg.

Cost

[$] MSP
Mfg.

Price

[$] Design
Option

L0 85.84 $9,913 $14,028 Baseline

L1 69.52 $10,073 $14,250 L0 +

ASCTRL

L2 60.76 $10,383 $14,681 L1 + CS2

L3 54.15 $11,019 $15,565 L2 + SC

L4 47.74 $11,919 $16,817 L3 + LED

L5 32.09 $15,024 $21,133 L4 + DR2

L6 18.42 $17,893 $25,120 L5 + DR3

L7 17.64 $18,117 $25,485 L6 + FLR2

L8 17.58 $18,158 $25,553 L7 + TCK2

L9 17.57 $18,167 $25,566 L8 + XC

L10 17.50 $18,228 $25,668 L9 + TCK3

L11 13.13 $22,413 $31,486 L10 + DR4

L12 13.09 $22,457 $31,550 L11 + FLR3

L13 13.01 $22,565 $31,728 L12 + TCK4

L14 12.94 $22,673 $31,906 L13 + TCK5

L15 12.83 $23,791 $33,317 L14 + INSH1

$0 $5,000 $10,000 $15,000 $20,000 $25,000 $30,000 $35,000

0.0 20.0 40.0 60.0 80.0 100.0Manufacturer Selling Price [$]

Daily Energy Consumption [kWh/day]



### Figure 5.5.5 Cost-Efficiency Cu rve for the D.C. Equipment Class [Medium, Number of Doors: Display, Passage, and Freight (8,1,0)]

5-61

### Table 5.5.6 Cost-Efficiency Data for the D.C. Large Equipment Class

Efficiency

Level Daily
Energy

Use [kWh/day] MPC
Mfg.

Cost

[$] MSP
Mfg.

Price

[$] Design
Option

L0 409.07 $62,175 $88,642 Baseline

L1 363.04 $63,325 $90,240 L0 + CS2

L2 331.01 $66,916 $95,231 L1 + SC

L3 297.67 $71,596 $101,737 L2 + LED

L4 199.83 $91,002 $128,712 L3 + DR2

L5 114.43 $108,932 $153,634 L4 + DR3

L6 114.32 $108,960 $153,673 L5 + XC

L7 113.80 $109,359 $154,304 L6 + TCK2

L8 109.75 $113,127 $160,551 L7 + FLR2

L9 82.44 $139,284 $196,909 L8 + DR4

L10 81.81 $139,882 $197,859 L9 + TCK3

L11 81.19 $140,614 $198,957 L10 + FLR3

L12 80.43 $141,667 $200,616 L11 + TCK4

L13 79.87 $142,719 $202,275 L12 + TCK5

L14 79.84 $142,919 $202,553 L13 + CS3

L15 79.22 $147,623 $209,091 L14 + ATG

$0 $50,000 $100,000 $150,000 $200,000 $250,000

0.0 100.0 200.0 300.0 400.0 500.0Manufacturer Selling Price [$]

Daily Energy Consumption [kWh/day]



### Figure 5.5.6 Cost-Efficiency Cu rve for the D.C. Equipmen t Class [Large, Number of Doors: Display, Passage, and Freight (50,2,0)]

5-62

### Table 5.5.7 Cost-Efficiency Data fo r the ND.F. Small Equipment Class

Efficiency

Level Daily
Energy

Use [kWh/day] MPC
Mfg.

Cost

[$] MSP
Mfg.

Price

[$] Design
Option

L0 25.67 $2,347 $3,484 Baseline

L1 13.12 $2,458 $3,638 L0 + SC

L2 12.82 $2,491 $3,685 L1 + LED

L3 12.52 $2,544 $3,767 L2 + TCK2

L4 12.16 $2,623 $3,891 L3 + TCK3

L5 12.12 $2,631 $3,902 L4 + XC

L6 12.01 $2,660 $3,945 L5 + FLR2

L7 11.56 $2,799 $4,161 L6 + TCK4

L8 11.48 $2,829 $4,204 L7 + FLR3

L9 11.15 $2,968 $4,420 L8 + TCK5

L10 10.26 $3,428 $5,060 L9 + AC

L11 9.69 $4,871 $6,950 L10 + INSH1

L12 9.39 $5,681 $8,076 L11 + VIP

L13 9.27 $6,053 $8,593 L12 + ATG

L14 8.99 $7,053 $9,983 L13 + VEST

L15 8.98 $7,303 $10,330 L14 + CS2

$0 $2,000 $4,000 $6,000 $8,000 $10,000 $12,000

0.0 10.0 20.0 30.0Manufacturer Selling Price [$]

Daily Energy Consumption [kWh/day]



### Figure 5.5.7 Cost-Efficiency Cu rve for the ND.F. Equipmen t Class [Small, Number of Doors: Display, Passage, and Freight (0,1,0)]

5-63

### Table 5.5.8 Cost-Efficiency Data fo r the ND.F. Medium Equipment Class

Efficiency

Level Daily
Energy

Use [kWh/day] MPC
Mfg.

Cost

[$] MSP
Mfg.

Price

[$] Design
Option

L0 55.25 $5,818 $8,821 Baseline

L1 24.40 $6,262 $9,437 L0 + SC

L2 24.10 $6,295 $9,484 L1 + LED

L3 24.00 $6,309 $9,503 L2 + XC

L4 23.15 $6,452 $9,724 L3 + TCK2

L5 22.13 $6,665 $10,055 L4 + TCK3

L6 21.70 $6,775 $10,218 L5 + FLR2

L7 20.44 $7,150 $10,797 L6 + TCK4

L8 20.15 $7,260 $10,961 L7 + FLR3

L9 17.86 $8,180 $12,239 L8 + AC

L10 16.95 $8,555 $12,818 L9 + TCK5

L11 15.33 $12,450 $17,941 L10 + INSH1

L12 14.51 $14,634 $20,977 L11 + VIP

L13 13.84 $16,634 $23,757 L12 + VEST

L14 13.47 $17,742 $25,297 L13 + ATG

L15 13.46 $17,992 $25,645 L14 + CS2

$0 $5,000 $10,000 $15,000 $20,000 $25,000 $30,000

0.0 20.0 40.0 60.0Manufacturer Selling Price [$]

Daily Energy Consumption [kWh/day]



### Figure 5.5.8 Cost-Efficiency Cu rve for the ND.F. Equipment Class [Medium, Number of Doors: Display, Passage, and Freight (0,1,1)]

5-64

### Table 5.5.9 Cost-Efficiency Data for the ND.F. Large Equipment Class

Efficiency

Level Daily
Energy

Use [kWh/day] MPC
Mfg.

Cost

[$] MSP
Mfg.

Price

[$] Design
Option

L0 105.04 $13,130 $19,978 Baseline

L1 51.78 $13,796 $20,903 L0 + SC

L2 51.54 $13,817 $20,932 L1 + XC

L3 50.65 $13,917 $21,072 L2 + LED

L4 48.82 $14,237 $21,564 L3 + TCK2

L5 46.61 $14,717 $22,302 L4 + TCK3

L6 45.42 $15,022 $22,759 L5 + FLR2

L7 42.69 $15,865 $24,050 L6 + TCK4

L8 38.63 $17,245 $25,968 L7 + AC

L9 37.83 $17,550 $26,425 L8 + FLR3

L10 35.87 $18,393 $27,715 L9 + TCK5

L11 35.60 $18,643 $28,063 L10 + CS2

L12 34.25 $21,183 $31,593 L11 + ATG

L13 34.16 $21,383 $31,871 L12 + CS3

L14 30.67 $30,135 $43,437 L13 + INSH1

L15 28.88 $35,044 $50,260 L14 + VIP

$0 $10,000 $20,000 $30,000 $40,000 $50,000 $60,000

0.0 50.0 100.0 150.0Manufacturer Selling Price [$]

Daily Energy Consumption [kWh/day]



### Figure 5.5.9 Cost-Efficiency Cu rve for the ND.F. Equipmen t Class [Large, Number of Doors: Display, Passage, and Freight (0,2,1)]

5-65

### Table 5.5.10 Cost-Efficiency Data fo r the D.F. Small Equipment Class

Efficiency

Level Daily
Energy

Use [kWh/day] MPC
Mfg.

Cost

[$] MSP
Mfg.

Price

[$] Design
Option

L0 79.22 $5,016 $7,127 Baseline

L1 68.74 $5,116 $7,266 L0 + ASCTRL

L2 46.66 $5,476 $7,767 L1 + SC

L3 40.46 $5,836 $8,267 L2 + LED

L4 40.29 $5,864 $8,313 L3 + TCK2

L5 34.76 $6,780 $9,586 L4 + DR2

L6 24.70 $8,503 $11,981 L5 + DR3

L7 24.49 $8,544 $12,049 L6 + TCK3

L8 23.42 $8,794 $12,397 L7 + CS2

L9 23.34 $8,816 $12,429 L8 + FLR2

L10 23.31 $8,823 $12,438 L9 + XC

L11 23.06 $8,896 $12,558 L10 + TCK4

L12 19.57 $10,116 $14,253 L11 + DR4

L13 19.52 $10,138 $14,285 L12 + FLR3

L14 19.33 $10,211 $14,404 L13 + TCK5

L15 17.84 $12,051 $16,962 L14 + AC

$0 $2,000 $4,000 $6,000 $8,000 $10,000 $12,000 $14,000 $16,000 $18,000

0.0 20.0 40.0 60.0 80.0 100.0Manufacturer Selling Price [$]

Daily Energy Consumption [kWh/day]



### Figure 5.5.10 Cost-Efficiency Cu rve for the D.F. Equipment Class [Small, Number of Doors: Display, Passage, and Freight (3,1,0)]

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### Table 5.5.11 Cost-Efficiency Data fo r the D.F. Medium Equipment Class

Efficiency

Level Daily
Energy

Use [kWh/day] MPC
Mfg.

Cost

[$] MSP
Mfg.

Price

[$] Design
Option

L0 170.22 $11,510 $16,301 Baseline

L1 142.26 $11,670 $16,523 L0 + ASCTRL

L2 104.31 $12,446 $17,602 L1 + SC

L3 94.77 $12,756 $18,033 L2 + CS2

L4 87.80 $13,566 $19,159 L3 + LED

L5 73.05 $16,010 $22,556 L4 + DR2

L6 72.81 $16,051 $22,624 L5 + TCK2

L7 45.97 $20,751 $29,157 L6 + DR3

L8 45.93 $20,760 $29,170 L7 + XC

L9 45.64 $20,821 $29,272 L8 + TCK3

L10 45.47 $20,865 $29,336 L9 + FLR2

L11 45.11 $20,972 $29,514 L10 + TCK4

L12 35.82 $24,225 $34,035 L11 + DR4

L13 35.71 $24,269 $34,100 L12 + FLR3

L14 35.45 $24,376 $34,278 L13 + TCK5

L15 32.94 $28,516 $40,032 L14 + AC

$0 $5,000 $10,000 $15,000 $20,000 $25,000 $30,000 $35,000 $40,000 $45,000

0.0 50.0 100.0 150.0 200.0Manufacturer Selling Price [$]

Daily Energy Consumption [kWh/day]



### Figure 5.5.11 Cost-Efficiency Cu rve for the D.F. Equipment Class [Medium, Number of Doors: Display, Passage, and Freight (8,1,0)]

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### Table 5.5.12 Cost-Efficiency Data for the D.F. Large Equipment Class

Efficiency

Level Daily
Energy

Use [kWh/day] MPC
Mfg.

Cost

[$] MSP
Mfg.

Price

[$] Design
Option

L0 811.05 $79,357 $113,532 Baseline

L1 755.37 $80,507 $115,131 L0 + CS2

L2 571.53 $84,888 $121,220 L1 + SC

L3 571.09 $84,916 $121,259 L2 + XC

L4 530.78 $89,597 $127,765 L3 + LED

L5 438.61 $104,870 $148,995 L4 + DR2

L6 270.88 $134,245 $189,826 L5 + DR3

L7 268.73 $134,644 $190,460 L6 + TCK2

L8 266.13 $135,243 $191,410 L7 + TCK3

L9 263.28 $135,975 $192,508 L8 + FLR2

L10 260.07 $137,027 $194,167 L9 + TCK4

L11 202.02 $157,356 $222,424 L10 + DR4

L12 200.11 $158,088 $223,523 L11 + FLR3

L13 197.80 $159,140 $225,182 L12 + TCK5

L14 197.60 $159,340 $225,460 L13 + CS3

L15 195.10 $164,044 $231,998 L14 + ATG

$0 $50,000 $100,000 $150,000 $200,000 $250,000

0.0 200.0 400.0 600.0 800.0 1000.0Manufacturer Selling Price [$]

Daily Energy Consumption [kWh/day]



### Figure 5.5.12 Cost-Efficiency Curve for the D.F. Equipmen t Class [Large, Number of Doors: Display, Passage, and Freight (50,2,0)]

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### 5.5.2 Refrigeration Cost-Efficiency Curves

Table 5.5.13 Cost-Efficiency Data for the DC.M.I Equipment Class (Small)

Efficiency

Level* Normalized Daily Energy Consumption [(kWh/day)/

(kBtu/h)] Manufacturer

Production Cost (MPC) [$] Normalized

MPC [$/(kWh/day)] Manufacturer Selling Price (MSP)

[$] Normalized

MSP [$/(kBtu/h)] Option

L0 1.96 $1,923 $163 $2,710 $229

- L1 1.53 $1,999 $137 $2,828 $194 L0 + CD2

L2 1.46 $2,038 $133 $2,886 $189 L1 + EV2

L3 1.33 $2,109 $138 $2,985 $195 L2 + ECM

L4 1.08 $2,409 $158 $3,402 $223 L3 + EM2

L5 1.06 $2,427 $159 $3,427 $224 L4 + CB2

L6 1.03 $2,511 $163 $3,544 $230 L5 + EB2

L7 0.98 $2,505 $193 $3,535 $273 L6 + SCR

$0 $50 $100 $150 $200 $250 $300

0.0 0.5 1.0 1.5 2.0 2.5Normalized Manufacturer Selling Price[$/(kBtu/h)]

Normalized Daily Energy Consumption [(kWh/day)/(kBtu/h)]



### Figure 5.5.13 Cost-Efficiency Curve for the DC.M.I Equipment Class (Small)

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### Table 5.5.14 Cost-Efficiency Data for the DC.M.I Equipment Class (Large)

Efficiency

Level* Normalized Daily Energy Consumption [(kWh/day)/

(kBtu/h)] Manufacturer

Production Cost (MPC) [$] Normalized

MPC [$/(kWh/day)] Manufacturer Selling Price (MSP)

[$] Normalized

MSP [$/(kBtu/h)] Option

L0 1.87 $2,613 $124 $3,696 $176

- L1 1.79 $2,664 $121 $3,772 $171 L0 + EV2

L2 1.41 $2,812 $105 $4,006 $149 L1 + CD2

L3 1.26 $2,954 $110 $4,204 $157 L2 + ECM

L4 1.02 $3,254 $121 $4,621 $172 L3 + EM2

L5 1.01 $3,291 $123 $4,672 $174 L4 + CB2

L6 0.97 $3,431 $127 $4,866 $180 L5 + EB2

L7 0.94 $3,705 $153 $5,247 $217 L6 + SCR

$0 $50 $100 $150 $200 $250

0.0 0.5 1.0 1.5 2.0Normalized Manufacturer Selling Price[$/(kBtu/h)]

Normalized Daily Energy Consumption [(kWh/day)/(kBtu/h)]



### Figure 5.5.14 Cost-Efficiency Curve for the DC.M.I Equipment Class (Large)

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### Table 5.5.15 Cost-Efficiency Data for the DC.M.O Equipment Class (Small)

Efficiency

Level* Normalized Daily Energy Consumption [(kWh/day)/

(kBtu/h)] Manufacturer

Production Cost (MPC) [$] Normalized

MPC [$/(kWh/day)] Manufacturer Selling Price (MSP)

[$] Normalized

MSP [$/(kBtu/h)] Option

L0 1.59 $2,194 $154 $3,102 $217

- L1 1.51 $2,221 $147 $3,142 $208 L0 + EV2

L2 1.25 $2,412 $137 $3,436 $195 L1 + CD2

L3 0.87 $2,612 $149 $3,714 $211 L2 + FHP

L4 0.81 $2,683 $153 $3,813 $217 L3 + ECM

L5 0.73 $2,992 $157 $4,242 $223 L4 + SCR

L6 0.67 $3,076 $161 $4,359 $228 L5 + EB2

L7 0.50 $3,376 $176 $4,776 $249 L6 + EM2

$0 $50 $100 $150 $200 $250 $300

0.0 0.5 1.0 1.5 2.0Normalized Manufacturer Selling Price[$/(kBtu/h)]

Normalized Daily Energy Consumption [(kWh/day)/(kBtu/h)]



### Figure 5.5.15 Cost-Efficiency Curve for the DC.M.O Equipment Class (Small)

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### Table 5.5.16 Cost-Efficiency Data for the DC.M.O Equipment Class (Large)

Efficiency

Level* Normalized Daily Energy Consumption [(kWh/day)/

(kBtu/h)] Manufacturer

Production Cost (MPC) [$] Normalized

MPC [$/(kWh/day)] Manufacturer Selling Price (MSP)

[$] Normalized

MSP [$/(kBtu/h)] Option

L0 1.70 $2,689 $128 $3,801 $181

- L1 1.63 $2,725 $124 $3,856 $175 L0 + EV2

L2 1.46 $2,999 $117 $4,237 $165 L1 + SCR

L3 1.22 $3,190 $113 $4,530 $160 L2 + CD2

L4 0.88 $3,390 $120 $4,808 $170 L3 + FHP

L5 0.64 $3,690 $130 $5,225 $185 L4 + EM2

L6 0.56 $3,833 $135 $5,423 $192 L5 + ECM

L7 0.55 $3,869 $137 $5,474 $193 L6 + CB2

L8 0.52 $4,009 $141 $5,669 $199 L7 + EB2

$0 $50 $100 $150 $200 $250

0.0 0.5 1.0 1.5 2.0Normalized Manufacturer Selling Price[$/(kBtu/h)]

Normalized Daily Energy Consumption [(kWh/day)/(kBtu/h)]



### Figure 5.5.16 Cost-Efficiency Curve for the DC.M.O Equipment Class (Large)

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### Table 5.5.17 Cost-Efficiency Data for the MC.M.I Equipment Class (Small)

Efficiency

Level* Normalized Daily Energy Consumption [(kWh/day)/

(kBtu/h)] Manufacturer

Production Cost (MPC) [$] Normalized

MPC [$/(kWh/day)] Manufacturer Selling Price (MSP)

[$] Normalized

MSP [$/(kBtu/h)] Option

L0 1.08 $ 729 $ 79 $1,029 $112

- L1 1.00 $ 739 $ 80 $1,043 $113 L0 + EB2

L2 0.98 $ 753 $ 81 $1,063 $115 L1 + EV2

L3 0.76 $1,053 $114 $1,480 $160 L2 + EM2

$0 $20 $40 $60 $80 $100 $120 $140 $160 $180

0.0 0.5 1.0 1.5Normalized Manufacturer Selling Price[$/(kBtu/h)]

Normalized Daily Energy Consumption [(kWh/day)/(kBtu/h)]



### Figure 5.5.17 Cost-Efficiency Curve for the MC.M.I Equipment Class (Small)

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### Table 5.5.18 Cost-Efficiency Data for the MC.M.I Equipment Class (Large)

Efficiency

Level* Normalized Daily Energy Consumption [(kWh/day)/

(kBtu/h)] Manufacturer

Production Cost (MPC) [$] Normalized

MPC [$/(kWh/day)] Manufacturer Selling Price (MSP)

[$] Normalized

MSP [$/(kBtu/h)] Option

L0 1.04 $1,617 $ 55 $2,288 $ 77

- L1 0.97 $1,648 $ 55 $2,329 $ 78 L0 + EB2

L2 0.95 $1,674 $ 56 $2,371 $ 79 L1 + EV2

L3 0.74 $1,974 $ 66 $2,788 $ 93 L2 + EM2

$0 $10 $20 $30 $40 $50 $60 $70 $80 $90 $100

0.0 0.5 1.0 1.5Normalized Manufacturer Selling Price[$/(kBtu/h)]

Normalized Daily Energy Consumption [(kWh/day)/(kBtu/h)]



### Figure 5.5.18 Cost-Efficiency Curve for the MC.M.I Equipment Class (Large)

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### Table 5.5.19 Cost-Efficiency Data for the DC.L.I Equipment Class (Small)

Efficiency

Level* Normalized Daily Energy Consumption [(kWh/day)/

(kBtu/h)] Manufacturer

Production Cost (MPC) [$] Normalized

MPC [$/(kWh/day)] Manufacturer Selling Price (MSP)

[$] Normalized

MSP [$/(kBtu/h)] Option

L0 6.60 $1,723 $349 $2,424 $491

- L1 6.14 $1,751 $323 $2,465 $455 L0 + EV2

L2 5.37 $2,046 $290 $2,876 $408 L1 + SCR

L3 4.58 $2,143 $279 $3,022 $394 L2 + CD2

L4 4.14 $2,214 $288 $3,122 $407 L3 + ECM

L5 4.00 $2,270 $293 $3,199 $413 L4 + EB2

L6 3.95 $2,288 $295 $3,225 $416 L5 + CB2

L7 3.77 $2,473 $319 $3,482 $449 L6 + DF2

L8 3.53 $2,773 $358 $3,899 $503 L7 + EM2

$0 $100 $200 $300 $400 $500 $600

0.0 2.0 4.0 6.0 8.0Normalized Manufacturer Selling Price[$/(kBtu/h)]

Normalized Daily Energy Consumption [(kWh/day)/(kBtu/h)]



### Figure 5.5.19 Cost-Efficiency Curve for the DC.L.I Equipment Class (Small)

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### Table 5.5.20 Cost-Efficiency Data for the DC.L.I Equipment Class (Large)

Efficiency

Level* Normalized Daily Energy Consumption [(kWh/day)/

(kBtu/h)] Manufacturer

Production Cost (MPC) [$] Normalized

MPC [$/(kWh/day)] Manufacturer Selling Price (MSP)

[$] Normalized

MSP [$/(kBtu/h)] Option

L0 6.01 $2,199 $222 $3,111 $314

- L1 5.67 $2,226 $208 $3,153 $294 L0 + EV2

L2 4.78 $2,382 $189 $3,400 $270 L1 + CD2

L3 4.17 $2,672 $197 $3,802 $280 L2 + SCR

L4 3.67 $2,814 $207 $4,000 $295 L3 + ECM

L5 3.56 $2,898 $212 $4,117 $301 L4 + EB2

L6 3.50 $2,935 $214 $4,168 $304 L5 + CB2

L7 3.34 $3,120 $228 $4,425 $323 L6 + DF2

L8 3.15 $3,420 $250 $4,842 $354 L7 + EM2

$0 $50 $100 $150 $200 $250 $300 $350 $400

0.0 2.0 4.0 6.0 8.0Normalized Manufacturer Selling Price[$/(kBtu/h)]

Normalized Daily Energy Consumption [(kWh/day)/(kBtu/h)]



### Figure 5.5.20 Cost-Efficiency Curve for the DC.L.I Equipment Class (Large)

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### Table 5.5.21 Cost-Efficiency Data for the DC.L.O Equipment Class (Small)

Efficiency

Level* Normalized Daily Energy Consumption [(kWh/day)/

(kBtu/h)] Manufacturer

Production Cost (MPC) [$] Normalized

MPC [$/(kWh/day)] Manufacturer Selling Price (MSP)

[$] Normalized

MSP [$/(kBtu/h)] Option

L0 5.81 $1,778 $360 $2,501 $506

- L1 5.39 $1,795 $331 $2,525 $466 L0 + EV2

L2 4.67 $2,090 $296 $2,936 $416 L1 + SCR

L3 4.13 $2,207 $293 $3,111 $414 L2 + CD2

L4 3.75 $2,278 $303 $3,210 $427 L3 + ECM

L5 2.88 $2,478 $329 $3,488 $464 L4 + FHP

L6 2.76 $2,534 $333 $3,566 $469 L5 + EB2

L7 2.72 $2,553 $336 $3,592 $473 L6 + CB2

L8 2.44 $2,853 $375 $4,009 $527 L7 + EM2

L9 2.27 $3,038 $400 $4,266 $561 L8 + DF2

$0 $100 $200 $300 $400 $500 $600

0.0 2.0 4.0 6.0 8.0Normalized Manufacturer Selling Price[$/(kBtu/h)]

Normalized Daily Energy Consumption [(kWh/day)/(kBtu/h)]



### Figure 5.5.21 Cost-Efficiency Curve for the DC.L.O Equipment Class (Small)

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### Table 5.5.22 Cost-Efficiency Data for the DC.L.O Equipment Class (Large)

Efficiency

Level* Normalized Daily Energy Consumption [(kWh/day)/

(kBtu/h)] Manufacturer

Production Cost (MPC) [$] Normalized

MPC [$/(kWh/day)] Manufacturer Selling Price (MSP)

[$] Normalized

MSP [$/(kBtu/h)] Option

L0 5.23 $2,281 $230 $3,225 $326

- L1 4.93 $2,302 $215 $3,257 $304 L0 + EV2

L2 4.21 $2,591 $208 $3,659 $293 L1 + SCR

L3 3.74 $2,793 $210 $3,971 $298 L2 + CD2

L4 2.85 $2,993 $225 $4,249 $319 L3 + FHP

L5 2.49 $3,136 $236 $4,447 $334 L4 + ECM

L6 2.39 $3,220 $240 $4,564 $340 L5 + EB2

L7 2.35 $3,257 $243 $4,614 $344 L6 + CB2

L8 2.20 $3,442 $256 $4,872 $363 L7 + DF2

L9 1.96 $3,742 $279 $5,289 $394 L8 + EM2

$0 $50 $100 $150 $200 $250 $300 $350 $400 $450

0.0 2.0 4.0 6.0Normalized Manufacturer Selling Price[$/(kBtu/h)]

Normalized Daily Energy Consumption [(kWh/day)/(kBtu/h)]



### Figure 5.5.22 Cost-Efficiency Curve for the DC.L.O Equipment Class (Large)

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### Table 5.5.23 Cost-Efficiency Data for the MC.L.I Equipment Class (Small)

Efficiency

Level* Normalized Daily Energy Consumption [(kWh/day)/

(kBtu/h)] Manufacturer

Production Cost (MPC) [$] Normalized

MPC [$/(kWh/day)] Manufacturer Selling Price (MSP)

[$] Normalized

MSP [$/(kBtu/h)] Option

L0 3.35 $ 706 $118 $ 996 $166

- L1 3.28 $ 718 $120 $1,014 $169 L0 + EV2

L2 3.13 $ 774 $128 $1,091 $180 L1 + EB2

L3 2.93 $ 959 $158 $1,349 $222 L2 + DF2

L4 2.68 $1,259 $208 $1,766 $291 L3 + EM2

$0 $50 $100 $150 $200 $250 $300 $350

0.0 1.0 2.0 3.0 4.0Normalized Manufacturer Selling Price[$/(kBtu/h)]

Normalized Daily Energy Consumption [(kWh/day)/(kBtu/h)]



### Figure 5.5.23 Cost-Efficiency Curve for the MC.L.I Equipment Class (Small)

5-79

### Table 5.5.24 Cost-Efficiency Data for the MC.L.I Equipment Class (Large)

Efficiency

Level* Normalized Daily Energy Consumption [(kWh/day)/

(kBtu/h)] Manufacturer

Production Cost (MPC) [$] Normalized

MPC [$/(kWh/day)] Manufacturer Selling Price (MSP)

[$] Normalized

MSP [$/(kBtu/h)] Option

L0 2.96 $1,596 $ 60 $2,257 $ 85

- L1 2.90 $1,619 $ 61 $2,293 $ 87 L0 + EV2

L2 2.74 $1,804 $ 68 $2,550 $ 96 L1 + DF2

L3 2.53 $2,104 $ 80 $2,967 $112 L2 + EM2

L4 2.47 $2,272 $ 85 $3,200 $120 L3 + EB2

$0 $20 $40 $60 $80 $100 $120 $140

0.0 1.0 2.0 3.0 4.0Normalized Manufacturer Selling Price[$/(kBtu/h)]

Normalized Daily Energy Consumption [(kWh/day)/(kBtu/h)]



### Figure 5.5.24 Cost-Efficiency Curve for the MC.L.I Equipment Class (Large)

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### REFERENCES

i American Metals Market, http://www.amm.com/.

ii U.S. Department of Labor, Bureau of Labor Statistics, Producer Price Indices

, http://www.bls.gov/ppi /.

iii Other insulation products such as expanded polystyrene, polyisocyanurate and polyurethane board stocks are also

used in WICF construction.

iv Downing, C.C. and Meffert, W.A, “Effectiveness of Cold-Storage Door Infiltration Protective Devices,” 3726 (RP-645), ASHRAE Transactions: Research, 1993

v Downing, C.C. and Meffert, W.A, “Effectiveness of Cold-Storage Door Infiltration Protective Devices,” 3726 (RP-645), ASHRAE Transactions: Research, 1993, p. 359

vi Downing, C.C. and Meffert, W.A, “Effectiveness of Cold-Storage Door Infiltration Protective Devices,” 3726 (RP-645), ASHRAE Transactions: Research, 1993, p. 359

vii Cost estimated based on DOE discussions with glass door component manufacturers and anti-sweat controller companies

viii http://blog.etundra.com/wp-content/Media/2009/09/23418.jpg

ix http://www.azpartsmaster.com/images/catalog/ashop/a31185.jpg

x Taizhou Koman Motor Products Co., Ltd

xi Rosenberg Ventilatoren GmbH

xii The EER values were assumed based on values specified in the WICF Test procedure NOPR

xiii Gosney and Olama (1975), ASHRAE Refrigeration Handbook, 12.4

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