CHAPTER 10. SHIPMENTS ANALYSIS 

TABLE OF CONTENTS 

10.1 INTRODUCTION ............................................................................................................ 10-1

10.2 OVERVIEW OF EQUIPMENT CLASSES AND MARKET SHARE ........................... 10-2

10.3 SHIPMENTS MODEL EQUATIONS ............................................................................. 10-3

10.3.1 Mathematical Formulation of the Shipments Model ......................................... 10-4

10.3.2 Stock Events....................................................................................................... 10-4

10.4 DATA INPUTS ................................................................................................................ 10-6

10.4.1 Historical Shipments .......................................................................................... 10-6

10.4.2 Historical Shipped Units .................................................................................... 10-6

10.4.3 Hotel/Motel, Health Care, and Small Office Space and Market Saturation ...... 10-7

10.5 RESULTS ....................................................................................................................... 10-11

LIST OF TABLES 

Table 10.2.1 Market Segments for the U.S. PTAC and PTHP Market in the Year 2000 ....... 10-3

Table 10.4.1 Historical Shipments (Units Shipped) of PTAC and PTHP Equipment by 

Cooling Capacity and Year ................................................................................ 10-7

Table 10.4.2 Baseline Square Footage of New Construction Forecasts by Census 

Division and Building Type for PTACs and PTHPS (Millions of Square 

Feet) CHANGE .................................................................................................. 10-8

Table 10.4.3 Historical Percentage of Shipped Units by Equipment class for PTAC and 

PTHP Equipment (2005).................................................................................... 10-9

Table 10.4.4 Estimated Replacement Sales of Standard Size PTAC and PTHP 

Equipment in the Year 2000 ............................................................................ 10-10

Table 10.4.5 Estimated New Sales of Standard Size PTAC and PTHP Equipment in the 

Year 2000 ......................................................................................................... 10-10

Table 10.4.6 Estimated Stock of PTAC and PTHP Units and Replacement Sales in the 

Year 2000 ......................................................................................................... 10-11

Table 10.5.1 Forecasted Shipments for PTAC and PTHP Equipment, Base Case for 

Selected Years .................................................................................................. 10-11

LIST OF FIGURES 

Figure 10.1.1 Flow Chart Showing Inputs to the Shipments Model ........................................ 10-1

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 EERE-2007-BT-STD-0012 COMMENT 32
CHAPTER 10. SHIPMENTS ANALYSIS 

10.1 INTRODUCTION

Shipments estimates for packaged terminal air conditioners (PTACs) and packaged 

terminal heat pumps (PTHPs) are a necessary input to the national energy savings (NES) and net 

present value (NPV) calculations and the manufacturer impacts analysis (MIA). This chapter 

describes the U.S. Department of Energy (DOE)’s methodology for projecting annual shipments 

and presents results. 

The shipments model is a description of PTAC and PTHP equipment stock flows as a 

function of year and age. No coupling is assumed between equipment categories, so the 

equations describe each type of equipment independently. In other words, DOE has not found 

evidence of equipment switching between equipment classes for PTACs and PTHPs. 

The shipments model results are driven primarily by historical shipments data for each of 

four equipment classes of PTACs and PTHPs under consideration. The flow chart presented in 

Figure 10.1.1 outlines the structure of the shipments model. The shipments model is in a 

Microsoft Excel spreadsheet format that is accessible on the Internet at: 

http://www.eere.energy.gov/buildings/appliance_standards/commercial/packaged_ac_hp.html. 

NEMS Bldg

Construction Forecast

ARI Estimate of 

Shipments (2005)

Initial Replacement 

Shipments 

Initial Shipments to New 

Construction 

Initial Equipment Stock

Estimated Lifetime 

of Equipment Stock

Shipments to New 

Construction 

Replacement 

Shipments 

Total 

Shipments By 

Equipment 

Class and 

Capacity

% Shipments by 

Equipment Class and 

Capacity (2005)

Equipment 

Stock by 

Equipment 

Class and 

Capacity

NEMS Bldg

Construction Forecast

ARI Estimate of 

Shipments (2005)

Initial Replacement 

Shipments 

Initial Shipments to New 

Construction 

Initial Equipment Stock

Estimated Lifetime 

of Equipment Stock

Shipments to New 

Construction 

Replacement 

Shipments 

Total 

Shipments By 

Equipment 

Class and 

Capacity

% Shipments by 

Equipment Class and 

Capacity (2005)

Equipment 

Stock by 

Equipment 

Class and 

Capacity

Figure 10.1.1 Flow Chart Showing Inputs to the Shipments Model 

DOE developed shipments forecasts by accounting for: (1) the growth in the building 

stock of hotel/motel, health care and office buildings that are the primary end users of PTACs 

and PTHPs; (2) market segments; (3) equipment retirements; and (4) equipment ages. 

The shipments model assumes that, in each year, each existing PTAC or PTHP either 

ages by one year or breaks down, and that equipment that breaks down is replaced. In addition, 

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 EERE-2007-BT-STD-0012 COMMENT 32
new equipment can be shipped into new commercial building floor space, and old equipment can 

be removed through demolitions. Historical shipments are critical to the development of the 

shipments model, since DOE used the historical data to calibrate the model. DOE’s primary 

source of historical data for shipments of PTACs and PTHPs was the shipment data provided by 

the Air Conditioning and Refrigeration Institute (ARI). ARI provided DOE with shipments data 

for 10 years (1997-2006), which allowed DOE to allocate sales of equipment to the different 

equipment classes. 

Initial stocks of equipment by equipment classes are calculated from industry-supplied 

data on replacements and new shipments and assumed equipment lifetimes based on industrysupplied data in a report by Ducker Worldwide1

. Because the non-standard size units are sold 

only for replacements of existing units, all shipments to new construction are standard size units. 

The forecast of shipments to new construction is driven by a forecast of new construction of 

lodging and small office space from the Energy Information Administration (EIA)’s National 

Energy Modeling System (NEMS). The sales to new construction are added by vintage to the 

existing stock, and as each vintage slowly retires, it is replaced, generating a demand for 

replacement shipments. The existing equipment stock, both standard and non-standard, retires 

slowly, and beginning in 2013, is assumed not to be fully replaced as the stock of buildings using 

this equipment slowly leaves the inventory. Each year, each of the three components of stock is 

updated with retirements, replacements, and new additions. 

Further, Chapter 11, national impact analysis of this Technical Support Document (TSD), 

discusses how to access the shipments model spreadsheet and other related spreadsheets, and 

appendix F provides basic instructions for using them. The rest of this chapter explains the 

shipments model in more detail. Section 10.3 presents the mathematical formulation of the 

model, section 10.4 describes the data inputs to the model, and section 10.5 presents the results 

for different amended energy-conservation standard level scenarios. 

The amended energy conservation standards for PTACs and PTHPs will set the minimum 

equipment efficiency in terms of energy efficiency ratio (EER) and coefficient of performance 

(COP) for all equipment within an equipment class. DOE conducted shipments forecasts for all 

of the trial standard levels (TSLs) for which NES and NPV are required. DOE is considering 

seven TSLs for each of the six equipment classes analyzed. Refer to chapter 9 of the TSD for 

detail discussion on TSL selection. 

10.2 OVERVIEW OF EQUIPMENT CLASSES AND MARKET SHARE 

DOE defined four equipment categories for PTACs and PTHPs: 1) standard size PTACs, 

2) standard size PTHPs, 3) non-standard size PTACs, 4) and non-standard size PTHPs. Standard 

size equipment has wall sleeve dimensions greater than or equal to16 inches high, or greater than 

or equal to 42 inches wide. Non-standard size equipment has wall sleeve dimensions less than 

16 inches high and less than 42 inches wide. The standard size PTAC and PTHP equipment 

classes are further divided into two categories each: large-capacity (i.e., cooling capacity greater 

than or equal to 10,000 Btu/h) and small-capacity (i.e., cooling capacity less than 10,000 Btu/h). 

Each category is characterized by a representative unit at 12,000 Btu/h and 9,000 Btu/h, 

respectively. This results in a total of six representative units to be analyzed. See Chapter 3 of 

the TSD for details. 

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 EERE-2007-BT-STD-0012 COMMENT 32
Ducker Worldwide divides PTAC and PTHP equipment into several market segments. 

Table 10.2.1 gives the approximate size of these market segments for the year 2000. 

Table 10.2.1 Market Segments for the U.S. PTAC and PTHP Market in the Year 2000 

Standard Size Units Non-Standard Size Units 

New Installations 98,000 0 

Replacementa 390,000 44,000 

Total 488,000 44,000 

Source: Ducker Worldwide (2001) 

Market data in Table 10.2.1 indicates that standard size units comprise about 92 percent 

of the total market, with non-standard size units sharing the remaining 8 percent of the total 

market. Furthermore, about 80 percent of standard size units are used for the replacement 

market and 20 percent for the new construction installation.b

 Non-standard units are 

manufactured and sold to replace existing units that were installed at sleeve sizes different from 

the common industry standard sleeve dimension (i.e., 42 inches wide and 16 inches high) 

adopted in 1985. 

Overall sales of PTAC and PTHP equipment were growing at the rate of about 

6.6 percent per year for standard size units and at almost 11.1 percent for non-standard size units 

during the first few years after 2000.1

 Future non-standard size unit sales growth is limited by the 

number of units installed before 1985, so rapid growth in annual replacements of non-standard 

size units should eventually decline to near zero as the pre-1985 built buildings are renovated or 

demolished. Future replacement sales of standard size units are limited by the total existing 

number installed and their age distribution. 

10.3 SHIPMENTS MODEL EQUATIONS 

This section begins with a definition of the different PTAC and PTHP equipment stock 

categories. DOE formulated the equations as updates of the distribution of stock in year (t) as a 

function of age (a) to year (t+1). Then DOE presented the different purchase decisions and, in 

the following section, provided a description of the data sources. DOE used a calculation of 

existing stock and the average age of the equipment as a basis for calculating replacement sales. 

Then, DOE subtracted replacement sales from historical total sales statistics to calculate the new 

sales of PTAC and PTHP equipment. DOE forecasted new sales as a function of new 

construction of hotel/motel, health care and office space. Sales of new and replacement 

equipment are recorded by the year sold, and each annual vintage is depreciated over the 

 

a

 Standard size units are sometimes used to retrofit buildings that did not originally have standard size units. DOE 

believes that this is a relatively rare occurrence, and assumes that changing PTAC sleeve sizes generally does not 

happen. Thus, replacements are assumed to be the same size as the equipment they replace. 

b

 In the context of this rulemaking analysis, “replacement” units are those used to replace an existing unit that has 

worn out or failed. Most of the units in the replacement market are standard sleeve size units. Ducker refers to nonstandard size units as “specialty” units because of their relatively narrow market application, and ASHRAE refers to 

them as “replacement” units, in part because they are sold only as replacements in legacy applications where the 

original unit had a non-standard sleeve size. In this analysis these are described as “non-standard” units. 

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 EERE-2007-BT-STD-0012 COMMENT 32
estimated equipment life. Sales in each year are allocated to the four equipment classes and 

representative units in proportion to their relative historical sales. 

10.3.1 Mathematical Formulation of the Shipments Model 

DOE uses two PTAC and PTHP equipment stock categories. The category U0(t,a) is the 

stock of existing units. Available information suggests that all units have had normal repairs that 

do not affect the lifetime of the equipment. 

PTAC and PTHP equipment lifetime can range from 1 to as many as 20 years. Based on 

discussions with industry experts and available literature reviews, DOE used a typical equipment 

life of 10 years for this analysis (see chapter 8 for further details). Also, available information 

suggests that the initial existing stock of equipment is assumed to have an average age of five 

years, based on the ten-year lifetime of a unit of equipment, and annual replacements going back 

10 years. The total stock of age a in a given year t is represented by 

 U(t,a) = U0 (t,a) Eq. 10.1 

 and the average age of the stock in year t is defined as 

 StockAge(t) = aU(t, a) x a / (U( t,a)) Eq. 10.2

where: 

U(t,a) = total stock of age a in a given year t

U0 (t,a) = stock of existing units 

StockAge(t) = average age of stock in year t

a = age of stock in years 

t = year. 

The shipments of new stock in a given year are Uship(t). By definition, the age of the 

equipment is zero in the year that it is shipped, so that Uship(t) = U(t,0). 

10.3.2 Stock Events 

In the transition from year t to year t+1, two things could happen to the stock of PTAC 

and PTHP equipment: 

existing equipment could break or be removed during a building renovation and be 

replaced, or 

the stock could simply age by one year. 

In the model, early replacements (i.e., existing equipment that is replaced before the end 

of its useful life) are not considered, and all broken equipment are assumed to be replaced. The 

following sections present the equations used to represent each possible event. 

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 EERE-2007-BT-STD-0012 COMMENT 32
10.3.2.1 Replacing Equipment 

DOE determined the probability that units of PTAC and PTHP equipment of average age 

a from initial stock U0 will break or will be replaced using a known function PB0(a)=0.07, based 

on a Weibull statistical distribution of retirements with a 10-year average life and maximum life 

of 20 years. Similarly, the probability that equipment of age a from stock U1 will break is given 

by a Weibull function PB1(a), with scale parameter of 10.2 and shape parameter of 2, truncated 

at 20 years. These probabilities do not depend on the model year t. DOE defines the quantities 

of replaced equipment as 

 UB(t, a) = PB0(a) x UB0(t,a) Eq. 10.3

where: 

UB0(t,a) = stock of existing units 

PB0(a) = probability that stock of existing units will break, or will be replaced 

U0(t,a) = stock of existing units 

a = average age of stock in years 

t = year. 

All broken units (or units removed during store renovations) are assumed to be replaced. 

10.3.2.2 New Equipment 

New PTAC and PTHP equipment will be purchased to replace the units described above. 

In addition, new PTAC and PTHP equipment will be purchased to install in newly constructed 

buildings. Available information suggests that the purchase of new PTAC and PTHP equipment 

that would go into new buildings is driven by the rate of construction of hotels/motels, health 

care facilities, and office floor space. 

By definition: 

 EFS (t+1) = EFS(t) + NFS (t) – DFS(t) Eq. 10.4

where: 

EFS(t) = the square footage of existing hotel/motel, health care, and office floor space in 

year t

NFS(t) = the square footage of new hotel/motel, health care, and office floor space added 

in year t (described in section 10.4.3) 

DFS(t) = the square footage of existing hotel/motel, health care and office floor space 

demolished in year t (described in section 10.4.3). 

The number of PTAC and PTHP units going into new buildings is 

 UN(t) = UN(0) x A0 x NFS(t)/ NFS(0) Eq. 10.5

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 EERE-2007-BT-STD-0012 COMMENT 32
10-6 

where: 

UN(t) = the number of units going into new buildings in year t

A0 = an overall scale factor which accounts for the number of units covered by the 

standard which are not used in all commercial building types. The default value 

for A0 is 1.0, and values of 0.5 and 1.5 are used for sensitivity testing. 

DOE has no information on the variation in the market saturation of PTAC and PTHP 

equipment by building type or over time. Therefore, in the model, the purchase of new 

equipment is driven by the construction of new floor space, and broken or removed equipment is 

replaced on a one-for-one basis. 

10.4 DATA INPUTS 

10.4.1 Historical Shipments 

Historical shipments are necessary to calibrate the shipments model to the existing 

market. DOE’s primary source of historical data for shipments of PTAC and PTHP equipment 

was the shipment data provided by the Air-Conditioning and Refrigeration Institute (ARI). 2 

ARI’s shipment data was broken out by specific PTAC and PTHP equipment class for 10 years 

(1997-2006), which allowed DOE to allocate sales of equipment to equipment classes. In 

addition, DOE used the Ducker Worldwide market study primarily to supplement the ARI 

shipment data. 

Within each of the equipment classes, the shipments data are disaggregated into detailed 

equipment and capacity ranges using the ARI shipment data. The Ducker Worldwide shipment 

data are defined in a way that allowed DOE to disaggregate the ARI shipment ranges and 

equipment categories into the equipment classes identified for this rulemaking. 

10.4.2 Historical Shipped Units 

Historical shipments data provide by ARI depict the annual amount of PTAC and PTHP 

equipment capacity introduced into the marketplace. DOE converted shipped units to percent of 

shipped units for use in the shipments model, to establish the PTAC and PTHP equipment 

market share attributed to each equipment class. The market share calculation and its use in 

forecasting shipments are explained in section 10.4.3.2. DOE used the Ducker Worldwide and 

ARI shipment data to derive shipped units in each equipment class. Table 10.4.1 presents the 

historical shipments of all PTAC and PTHP equipment by cooling capacity ranges and the year 

of shipment. 

 EERE-2007-BT-STD-0012 COMMENT 32
Table 10.4.1 Historical Shipments (Units Shipped) of PTAC and PTHP Equipment by 

Cooling Capacity and Year 

Cooling

Capacity

(Thousand 

Btu/h)

Year of Shipment* 

1997 1998 1999 2000 2001 2002 2003 2004 2005 2006**

PTAC

7.0 & 

Under 17,100 17,965 17,134 14,633 15,655 14,278 13,019 18,780 19,359 22,861 

7.1–10.0 89,064 93,250 89,492 74,767 71,111 68,193 72,877 81,906 91,989 104,234 

10.1–13.0 95,065 97,233 92,039 86,002 83,268 86,516 88,076 100,123 112,853 121,682 

13.1–16.0 40,309 44,532 45,057 43,834 42,077 46,332 46,271 47,630 52,350 55,902 

16.1 & 

Over 0 0 0 0 0 0 0 0 0 - 

Subtotal 241,538 252,980 243,722 219,236 212,111 215,319 220,243 248,439 276,551 304,680 

PTHP 

7.0 & 

Under 11,898 15,763 15,116 10,935 10,345 9,374 9,994 10,656 14,455 15,900 

7.1–10.0 78,666 89,556 78,953 66,826 65,214 63,446 63,827 71,756 73,287 89,742 

10.1–13.0 67,451 74,600 73,764 66,680 63,236 62,844 65,146 70,559 74,973 81,316 

13.1–16.0 34,004 37,692 41,682 38,465 36,923 38,181 39,570 44,229 44,459 48,313 

16.1 & 

Over 0 0 0 2 0 0 77 0 153 - 

Subtotals 192,019 217,611 209,515 182,908 175,718 173,845 178,614 197,200 207,327 235,271 

 Total (ARI) 433,557 470,591 453,237 402,144 387,829 389,164 398,857 445,639 483,878 539,951 

* Source: ARI. 

** For the year 2006, ARI reported shipments through October. The table values have been adjusted to a 12-month 

basis. 

10.4.3 Hotel/Motel, Health Care, and Small Office Space and Market Saturation 

The amount of commercial building floor space is the main driver for PTAC and PTHP 

equipment shipments and is one of the basic inputs into the shipments model. As discussed in 

section 10.3.2, the model divides commercial building floor space into two components: new 

construction floor space (NFS) and existing building floor space (EFS). 

For this analysis, commercial square footage with PTAC and PTHP equipment refers to 

both new and existing stock of commercial buildings. 

10.4.3.1 New Construction Floor Space 

DOE took the projected floor space construction after the year 2003 from the National 

Energy Modeling System (NEMS) projection published in the Annual Energy Outlook 2008 

(AEO 2008).3 AEO 2008 lists the projections for individual years 2004-2030. Table 10.4.2 

shows 2006, 2010, 2015, 2020, 2025 and 2030 for two building types: lodging (which includes 

hotels, motels, nursing homes and assisted care facilities) and small office (which includes the 

type offices covered in this analysis). Beyond 2030, DOE extrapolated NFS from the 10-year 

trend of NEMS projected data between 2020 and 2030. 

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 EERE-2007-BT-STD-0012 COMMENT 32
Table 10.4.2 Baseline Square Footage of New Construction Forecasts by Census Division 

and Building Type for PTACs and PTHPS (Millions of Square Feet) CHANGE 

Census 

Division 

Building 

Type 

Year of Construction 

2005 2010 2015 2020 2025 2030 

New 

England 

Lodging 7.4 7.6 8.1 9.2 10.1 11.1 

Small 

Office 6.0 4.3 5.6 6.6 5.6 5.8 

Total 13.4 11.9 13.7 15.8 15.8 16.9 

Mid 

Atlantic 

Lodging 19.6 17.7 19.7 19.8 23.1 25.8 

Small 

Office 20.7 14.1 16.5 19.5 17.8 18.5 

Total 40.3 31.8 36.3 39.4 40.9 44.2 

East 

North 

Central 

Lodging 12.5 13.5 14.4 15.4 16.8 18.3 

Small 

Office 19.3 18.7 22.1 22.4 21.6 24.5 

Total 31.8 32.2 36.5 37.7 38.4 42.8 

West 

North 

Central 

Lodging 14.9 16.5 13.2 17.2 18.0 19.5 

Small 

Office 10.5 12.4 14.5 13.4 14.7 15.3 

Total 25.4 28.9 27.8 30.6 32.7 34.8 

South 

Atlantic 

Lodging 20.8 26.0 26.5 27.9 34.9 33.2 

Small 

Office 23.6 21.7 27.9 31.1 29.9 30.2 

Total 44.4 47.8 54.5 58.9 64.8 63.5 

East 

South 

Central 

Lodging 7.8 11.3 9.9 10.0 12.7 13.3 

Small 

Office 6.7 7.4 7.4 7.6 8.0 8.2 

Total 14.5 18.7 17.3 17.7 20.7 21.6 

West 

South 

Central 

Lodging 9.4 9.6 10.7 11.4 12.7 14.1 

Small 

Office 12.4 13.8 15.4 16.8 18.4 20.3 

Total 21.8 23.4 26.1 28.2 31.1 34.4 

Mountain Lodging 12.3 12.2 11.9 14.5 15.7 17.1 

Small 

Office 8.0 12.1 18.1 14.1 14.2 17.4 

Total 20.3 24.3 30.0 28.6 29.8 34.5 

Pacific Lodging 15.3 16.4 18.2 19.9 22.3 24.0 

Small 

Office 28.1 22.7 22.2 26.1 28.8 27.7 

Total 43.4 39.1 40.5 46.1 51.1 51.7 

Total Lodging 120.2 130.8 132.7 145.3 166.2 176.4 

Small 

Office 135.1 127.3 149.8 157.7 159.1 168.0 

Total 255.3 258.1 282.5 303.0 325.3 344.3 

Source: AEO 2008.3

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 EERE-2007-BT-STD-0012 COMMENT 32
The total of new space conditioning capacity is the estimated total shipments in units for 

2006, multiplied by an index of new construction of square feet of the relevant commercial 

building space for each future year, divided by its 2006 value. The average rate of change in the 

construction index between 2020 and 2030 is used to project forward after 2030 until 2042, the 

last year in which PTAC and PTHP units are added. All existing PTACs and PTHPs are 

presumed to be replaced by a unit of the same equipment class and capacity (but not necessarily 

the same efficiency, since improved efficiency is possible during replacement) if it fails or is 

removed during a renovation. If the building is removed, the PTAC or PTHP is not replaced. 

10.4.3.2 Market Shipments 

DOE used the above shipments data to estimate the market shipments in year t of each 

PTAC and PTHP equipment class y, MKTSHIP(t,y), defined in terms of units shipped for both 

new and replacement markets. DOE assumed that the percent of shipments in each equipment 

class is constant over time and the lifetime of each equipment class is the same (10 years), so the 

ratio of shipments to a class is indicative of the market share for that class, MKT(y). DOE 

estimated the MKT(y) for a particular equipment class to be a constant value equal to the average 

of the yearly percent historical shipments to that class. These percentages are reported in 

Table 10.4.3. 

MKTSHIP(t,y) = MKT(y) x (UN(t) + UB(t)) Eq. 10.6

where: 

MKTSHIP(t,y) = total market shipments of equipment class y in year t, 

MKT(y) = percentage of total market shipments of equipment class y, 

UN(t) = total shipments to new buildings in year t, 

UB(t) = total replacement shipments in year t. 

Table 10.4.3 Historical Percentage of Shipped Units by Equipment class for PTAC and 

PTHP Equipment (2005) 

Representative Equipment 

and Cooling Capacity Description Percentage of Shipped Units 

Standard Size PTAC 

9,000 Btu/h

Includes all standard size PTAC units with cooling capacities 

less than 10,000 Btu/h 19.7% 

Standard Size PTAC 

12,000 Btu/h

Includes all standard size PTAC units with cooling capacities 

greater than or equal to 10,000 Btu/h 29.0% 

Standard Size PTHP 

9,000 Btu/h

Includes all standard size PTHP units with cooling capacities less 

than 10,000 Btu/h 15.4% 

Standard Size PTHP 

12,000 Btu/h

Includes all standard size PTHP units with cooling capacities 

greater than or equal to 10,000 Btu/h 21.0% 

Non-Standard Size PTAC 

11,000 Btu/h 

Includes all cooling capacities of non-standard-size PTAC units 8.5% 

Non-Standard Size PTHP 

11,000 Btu/h 

Includes all cooling capacities of non-standard-size PTHP units 6.4% 

Total 100% 

Sources: ARI and Ducker Worldwide, Inc. and 2000 Screening Analysis comments. c

 

c

 Refer to DOE’s Energy Conservation Program for Consumer Products: Screening Analysis for EPACT-Covered 

Commercial HVAC and Water-Heating Equipment Screening Analysis. April, 2000. 

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 EERE-2007-BT-STD-0012 COMMENT 32
DOE estimated total sales by adding replacement sales to new sales in each year. Taking 

the year 2000 as a baseline year and noting that 80 percent of the year 2000 market for standard 

size PTAC and PTHP equipment was for replacement of existing units, DOE estimated the total 

number of units for each equipment class that were replacing equipment.1

 DOE assumed that 

new units last an average of 10 years and that the average age of the existing stock is 5 years 

(half of an average lifetime). DOE set up an inventory accounting scheme to keep track of 

required replacements through the life of the buildings and the aging of new units as they are 

added to the inventory each year. 

Ducker provides breakdowns of sales of standard size PTAC and PTHP equipment for 

the year 2000 by cooling capacity.1

 Derived from the ARI shipment data for the year 2000 and 

the Ducker report, Table 10.4.4 shows the number of sales by cooling capacity and type of 

standard size PTAC unit in 2000. Subtracting out hydronic units, a niche market whose sales are 

assumed to be replacement sales and constant over time, these adjusted percentages (shown in 

Table 10.4.5) are applied to total sales of new units. 

Table 10.4.4 Estimated Replacement Sales of Standard Size PTAC and PTHP Equipment 

in the Year 2000 

Type of Unit 

Equipment Capacity 

7,000 Btu/h 9,000 Btu/h 12,000 Btu/h 15,000 Btu/h Total Sales 

PTAC 10,294 52,596 60,500 30,836 154,226 

PTHP 7,791 47,611 47,507 27,407 130,316 

Hydronic 132 673 774 395 1,973 

Total 18,216 100,881 108,781 58,637 286,515 

Source: ARI data, adjusted by percentages reported by Ducker 2000. 

Table 10.4.5 Estimated New Sales of Standard Size PTAC and PTHP Equipment in the 

Year 2000 

Type of Unit 

Equipment Capacity 

7,000 Btu/h 9,000 Btu/h 12,000 Btu/h 15,000 Btu/h Total 

PTAC 3,414 16,672 18,284 8,572 46,942 

PTHP 2,033 12,230 15,427 8,965 38,655 

Total 5,447 28,903 33,710 17,537 85,597 

Source: ARI data, adjusted by percentages reported by Ducker 2000. 

A Weibull distribution with an average age of 10 years for the stock of PTAC and PTHP 

equipment would retire approximately eight percent of the PTAC and PTHP equipment stock 

annually. That is, replacement sales would equal about eight percent of the existing stock. This 

means that the 286,515 replacements of standard size units in the year 2000 (Table 10.4.4) 

corresponds to about 3.58 million total existing standard size units (Table 10.4.6) in the market. 

In addition, there are 44,000 non-standard size units shown in Table 10.2.1 that are being used to 

replace stock that was estimated to be 15 to 25 years old in the year 2000.1

 In this case, the 

hotels/motels and other businesses are likely replacing more than one year’s equipment failures 

as part of property refurbishment and upgrade. This assumption is supported by the fact that the 

rapid growth in non-standard size unit replacement sales (11.1 percent per year) began in about 

1997, when the stock would have been 12 to 22 years old. At that time, annual equipment 

failures would have average 3.3 percent per year and are known to have been about 30,000 units 

per year. If the 1997 sales was replacement of failures only, then the total number of units in the 

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stock would have been about 900,000. If 3.3 percent is used as the average failure rate, then the 

stock of non-standard units would have been 900,000 units (Table 10.4.6). With 3 years of 

catch-up, by the year 2000, an extra 25,000 units would have been purchased (14,000 in the year 

2000 since Ducker estimates a total of 44,000 non-standard size sales in that year), which would 

have made the non-standard size stock average age younger by about one year compared with 

1997, but would not have increased the size of the stock. Table 10.4.6 provides the resulting 

stock estimates and replacement sales for the year 2000.

Table 10.4.6 Estimated Stock of PTAC and PTHP Units and Replacement Sales in the 

Year 2000 

Stock (Units) Annual Replacement Sales (Units) 

Standard Size Units 3,581,440 286,515 

Non-standard Size Units 900,000 30,000 

Non-standard Size Units N/A 14,000 (Catch-up sales) 

Total 4,481,440 330,515 

10.5 RESULTS 

Table 10.5.1 shows the forecasted shipments for PTAC and PTHP equipment classes for 

the base case efficiency level as listed in ASHRAE/IESNA Standard 90.1-1999 for selected 

years from 2012 to 2042. As equipment purchase price increases with efficiency, a drop in 

shipments is expected. Although there is a provision in the shipments analysis spreadsheet for a 

change in shipments as the trial standard level increases (and the equipment becomes more 

expensive), DOE had no information with which to calibrate such a relationship. Therefore, for 

the NOPR analysis, DOE assumed that total shipments do not change with trial standard levels. 

Table 10.5.1 also shows the cumulative shipments for PTAC and PTHP equipment from 2012 to 

2042. 

Table 10.5.1 Forecasted Shipments for PTAC and PTHP Equipment, Base Case for 

Selected Years 

Equipment

Thousands of Units Shipped by Year and Equipment Class 

2012 2015 2020 2025 2030 2035 2040 2042 

Cumulative 

Shipments 

(2012-2042) 

Standard Size 

PTACs 271 284 317 359 394 440 490 512 11,700 

Standard Size 

PTHPs 202 212 237 268 294 329 366 382 8,745 

Non-Standard 

Size PTACs 17 16 15 13 12 11 10 9 398 

Non-Standard 

Size PTHPs 13 12 11 10 9 8 7 7 300 

Total 503 525 579 650 709 787 873 910 21,143 

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10-12 

REFERENCES 

1. Ducker Worldwide. 2001. 2000 U.S. Market for Residential and Specialty Air 

Conditioning: PTAC (Packaged Terminal Air Conditioning). HVAC0002. Final Report, 

March 2001. Ducker Industrial Standards, 6905 Telegraph Road Suite 300, Bloomfield 

Hills, Michigan 48301. 

2. Air-Conditioning and Refrigeration Institute, 4100 N. Fairfax Drive, Suite 200, Arlington, 

Virginia 22203, U.S.A. 

3. EIA (Energy Information Administration). 2008. Annual Energy Outlook 2008. 

DOE/EIA-0383(2008). U.S. Department of Energy, Energy Information Administration, 

Washington D.C. 

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