Energy Conservation Standards f

Commercial Unitary Air Conditioners and 

ANOPR Public Meeting

Engineering Analysis 

Building Technologies Program

Office of Energy Efficiency and Renewable E

U.S. Department of Energy

September 30, 2004

EE-RM-STD-01-375 COMMENT 25H
ANOPR Analyses Flow Diagra

ScreeningAnalysis

EngineeringAnalysis

Energy Use & End-Use LoadCharacterization

ShipmentsAnalysis

Markups forEquipmentPriceDetermination

Life-CycleCost andPayback Period Analyses

Market & Technology Assessment

EE-RM-STD-01-375 COMMENT 25H
Purpose

 Market & Technology Assessment

• To characterize the commercial unitary AC and HP ma

available equipment efficiencies and shipments by pro

 Screening Analysis

• To identify design options that increase efficiency and 

criteria established by DOE to determine which design which to screen out

 Engineering Analysis

• To characterize manufacturer cost-efficiency relations

equipment

• To evaluate design options that improve efficiency rela

units

EE-RM-STD-01-375 COMMENT 25H
ANOPR Issues for Public Comm

 Approaches to Analyses for Split Systems, Heat 

Niche Equipment (ANOPR Issue #1)

 Alternative Refrigerant Analysis (ANOPR Issue #2 Design-Option Analysis and Maximum Energy Ef

(ANOPR Issue #4)

 Technologies that Affect Full- or Part-Load Perfor

Issue #18) 

EE-RM-STD-01-375 COMMENT 25H
Market and 

Product Classes

 Air-cooled unitary air conditioners and air-source 

between 65,000 Btu/h and 240,000 Btu/h, including

• Single package air conditioners and heat pumps• Split system air conditioners and heat pumps

ASHRAE Standard 90.1-1999 Minimum Efficiency (EE

(Assumed as Baseline Efficiency)

Equipment Type

≥65,000 to <135,00

Btu/h cooling capac

Single Package: Air Conditioner 10.3 

Single Package: Year-round Air Conditioner 10.1 

Split System: Condensing Unit, Coil with Blower 10.3 Single Package: Heat Pump 10.1 

Split System: Heat Pump with Remote Outdoor Unit 10.1 

EE-RM-STD-01-375 COMMENT 25H
Market and 

Market Shares and Unit Shipme

 Approximately 300,000 units covered by this rulemaking we

2000 (2001 U.S. Census data).

 Air conditioners account for about 90% of the covered mark

account for the remaining 10%.

 Majority of market share is held by four manufacturers.

 Significant portions of the market are held by two other man

 Year-round (units with gas heating) single package units are 

configuration.

21%

23%

56%

Year RoundSingle Pkg Other SinglPkgSplit

EE-RM-STD-01-375 COMMENT 25H
Screening Analysis Method

 Design options screened using the following crite

• Technological feasibility• Practicability to manufacture, install and service• Adverse impacts on product utility or product availabilit• Adverse impacts on health or safety

EE-RM-STD-01-375 COMMENT 25H
Design Options Selected for Further Co

Technologies that enhance EER

 Increase evaporator or condenser coil area Change the number of coil rows High-efficiency fan motors or compressors Micro-channel heat exchangers  Deep coil heat exchangers Air-foil or backward-curved centrifugal fans Increase evaporator or condenser fan diameter Synchronous (toothed) belts Direct drive fans High-efficiency propeller condenser fans Low pressure loss filter Reduce air leakage paths within unit

EE-RM-STD-01-375 COMMENT 25H
Technologies that Affect Full- or Part-Load 

(ANOPR Issue #18)

The Department invites comment on analyzing the technologies that can reduce EER, or are EER-neutannual energy consumption, and the implications benergy savings and consumer life-cycle costs.

EE-RM-STD-01-375 COMMENT 25H
Engineering Analysis Proces

 Define Equipment Classes and Baseli Select Teardown Units, Perform Teard

Materials, Develop Cost Model, Valida

 Develop Manufacturers’ Cost-Efficien

Curves, Aggregate Curves to an Indus

 Identify Design Options, Develop Perf

Cost Model to Design Options, ValidaRelationship

 Conduct R-410A Analysis, Incorporate 

Product 

Selection

Design Option 

Analysis

Cost Model 

Development

Cost-Efficiency 

Curve 

Development

Additional 

Analyses

EE-RM-STD-01-375 COMMENT 25H
Product Selection

8 9 10 

8 9 10 

ASHRAE 

90.1-1999 Level1

EPCA 1992 

Level

7.5-ton Products

15-ton Products

1 Based on ASHRAE 90.1-1999 Mandatory Minimum EER, including a reduction of 0.2 for units having a heating 

EE-RM-STD-01-375 COMMENT 25H
Fixed Costs  Equipment and Plant Depreciation Tooling Amortization Equipment Maintenance Utilities Indirect Labor Cost of Capital Overhead LaborVariable Costs Manufactured Materials Purchased Materials Fabrication Labor Assembly Labor Shipping Indirect Materials

Direct

Labor

Direct

Materials

Factory

Expense

General

Expense

Sales

Expense

Profit

Manufacturing 

Cost

Corporate Expenses Research and Development Profit General & Administration Warranty Taxes Sales and Marketing

Shipping

Manufacturing Cost Compone

EE-RM-STD-01-375 COMMENT 25H
Factory Cost Brea

Model A Model B 

Factory Cost ($)

Factory Cost Breakdown

Labor

Material

Overhead & Ship

Depreciation

TOTAL

factory cost

Model A

$$$$$

Model B

$$$$$

Model C

$$$$$

Cost Model Validation

ILLUSTRATIVE

EXAMPLE

EE-RM-STD-01-375 COMMENT 25H
Cost Efficiency Curve Developm

An exponential curve was fit to each manufacturer’s costefficiency points individually.

1

The data points were then normalized so that each manufacturer curve intersected at the ASHRAE 90.1-1999 EER level.

2

Nextexpowas fnormpointmanuextracurve EER.

3

EER

Normalized Product Cost

E

Normalized Product Cost

EER

Absolute Product Cost

EE-RM-STD-01-375 COMMENT 25H
7.5 Ton Cost-Efficiency Res

-$250

$0

$250$500$750

$1,000

8.5 9.0 9.5 10.0 10.5 11.0 

EER

Product Cost Delta ($) ASHRAE 90.1-1999 Standard1

Upper 95% Confidence Interval2Industry Average Cost-Efficiency CurveLower 95% Confidence Interval

1 Based on ASHRAE 90.1-1999 Mandatory Minimum EER, including a reduction of 0.2 for units having a heating 2 Confidence Interval represents the accuracy of the mean regression curve-fit (i.e., There is a 95% probability th

products at a given EER level would fall within the confidence interval).

EE-RM-STD-01-375 COMMENT 25H
a

t

c

an

ex

9.5 10 10.5 11 11.5 

EER

Normalized Product CostILLUSTRATIVE

Illustrative Cost-Efficiency Curve 

Design Option Analysis

Manufacturer AManufacturer BManufacturer CDesign Options

EE-RM-STD-01-375 COMMENT 25H
Design Option Analysis Approa

BASELINE APPROACH DESCR

Increases either c

while adjusting fa

motor size, subcool, a

Increases either e

while adjusting b

blowers, subcool, an

An existing 

product

is the 

starting point 

for the 

design process

Condenser Coil

1

Evaporator Coil

2

EER De

7.5-ton 

¿ 10.5

15-ton 

¿ 11.0

The design options werEER design targets whmodeling guidelines sugmanufacturers

Modeling Parameters

• Evaporator temperature• SHR• Condensing temperature• Condenser exit temperature• Condenser refrigerant 

∆

P

• Condenser face velocity• Blower motor efficiency• Condenser fan motor efficiency• System capacity vs. baseline

EE-RM-STD-01-375 COMMENT 25H
Validation of Cost-Efficiency Cu

-$250

$0

$250$500$750

$1,000

8.5 9.0 9.5 10.0 10.5 11.0 

EER

Product Cost Delta ($) ASHRAE 90.1-1999 Standard1 Manufacturer “A” Design Options Manufacturer “B” Design Options

Upper 95% Prediction Interval2Upper 95% Confidence Interval3Industry Average Cost-Efficiency CurveLower 95% Confidence IntervalLower 95% Prediction Interval

1 Based on ASHRAE 90.1-1999 Mandatory Minimum EER, including a reduction of 0.2 for units having a heating 2 Prediction Interval represents the accuracy of predicting the cost of any single unit given its EER.3 Confidence Interval represents the accuracy of the mean regression curve-fit (i.e., There is a 95% probability t

products at a given EER level would fall within the confidence interval).

EE-RM-STD-01-375 COMMENT 25H
Design-Option Analysis and Max

Energy Efficiency Levels 

(ANOPR Issue #4)

The Department invites comments on the approach design-option modeling for verifying the manufacturefficiency relationship.The Department invites comments on the design optestimating the manufacturing cost and efficiency rel11.5 EER.The Department invites comments on other design oDepartment should consider.The Department invites comments on assumptions fmaximum technologically feasible design.

EE-RM-STD-01-375 COMMENT 25H
 Because of the phaseout of CFC refrigerants, the engineering 

the cost-efficiency relationship of R-410A systems differs from 

 The properties of R-410A are different from those of R-22 (hi

requires modification of existing refrigeration components).

 The critical parameters in the analysis are the cost differentia

high efficiency units (rather than absolute cost) and whether t410A vs. R-22 products. R-4

R-

$ of R-410A

$ of 

R-410A Analysis

Product Cost Delta

EER

 The 7.5-ton R-410A design option points based on a represe

follow a trend that is similar to the R-22 cost-efficiency curve. 

in the post ANOPR phase.

EE-RM-STD-01-375 COMMENT 25H
R-410A Analysis Preliminary Assu

 Although design pressures are higher, the diamet

of the copper tubing remains the same. 

 R-410A scroll compressors are less efficient than 

scroll compressors, but more efficient than low-ereciprocating compressors.

 The higher heat-transfer coefficients of R-410A pr

lower condensing temperatures than R-22 for sim

 The evaporating temperature limits for the R-410A 

same as the R-22 system.

EE-RM-STD-01-375 COMMENT 25H
7.5 Ton R-410A Analysis Resu

 The R-410A points fall within the prediction interval of th

-$250

$0

$250$500$750

$1,000

8.5 9.0 9.5 10.0 10.5 11.0 1

EER

Product Cost Delta ($) ASHRAE 90.1-1999 Standard1 R-410A Design Options

Upper 95% Prediction Interval (R-22)Upper 95% Confidence Interval (R-22)Industry Average Cost-Efficiency Curve (R-22Lower 95% Confidence Interval (R-22)Lower 95% Prediction Interval (R-22)

1 Based on ASHRAE 90.1-1999 Mandatory Minimum EER, including a reduction of 0.2 for units having a heating 

EE-RM-STD-01-375 COMMENT 25H
Alternative Refrigerant Analys

(ANOPR Issue #2)

The Department seeks comments or data that can reincremental cost-efficiency relationship associated wsystems.The Department seeks comments on alternative refrthan R-410A, that the Department should consider.

EE-RM-STD-01-375 COMMENT 25H
Approaches to Analyses for Split Systems

and Niche Equipment 

(ANOPR Issue #1)

The Department invites comments on applying the crelationships developed for single package air condAC systems.The Department invites comments on the approach equipment classes, such as portable units and exploproof/hazardous duty units.The Department invites comments on addressing enstandards for commercial unitary heat pumps in a wconsistent with the ASHRAE methodology used to sASHRAE/IESNA Standard 90.1-1999 levels.

EE-RM-STD-01-375 COMMENT 25H
DOE proposes to develop heating COP (47° F) requirements baseEER and COP as determined from market data, as used by ASHR

2.903.003.103.203.303.403.50

8.0 9.0 10.0 11.0 

EER

COP

HSP-AHRCU-A-CB90.1-1999 Requirements, 65-13590.1-1999 Requirements, 135-240Linear Regession (HSP-A)Linear Regression (HRCU-A-CB)

Approaches to Analyses for Split Systems

and Niche Equipment (continu

(ANOPR Issue #1)

EE-RM-STD-01-375 COMMENT 25H
Other Issues

The Department seeks comments and recommenstakeholders on any other aspects related to the Analysis.

EE-RM-STD-01-375 COMMENT 25H