10-D-i

APPENDIX 10-D. EFFICIENCY TREND SENSITIVITY ANALYSIS FOR SPLIT 

SYSTEM CENTRAL AIR CONDITIONER REPLACEMENT UNITS

TABLE OF CONTENTS

10-D.1 EFFICIENCY TREND ........................................................................................10-D-1

10-D.2 NES AND NPV RESULTS.................................................................................10-D-4

LIST OF TABLES

Table 10-D.1.1 Split System Central Air Conditioner, Coil-Only Replacement Units: 

Base Case Efficiency Distributions and SWEFs, Sensitivity Case..........10-D-3

Table 10-D.2.1 Split System Central Air Conditioners: Cumulative National NES 

Results from 2016-2045, Residential and Commercial Sector, 

Sensitivity Case........................................................................................10-D-4

Table 10-D.2.2 Split System Central Air Conditioners: Cumulative National NPV 

Results from 2016-2045, Sensitivity Case...............................................10-D-4

LIST OF FIGURES

Figure 10-D.1.1 Split System Central Air Conditioner, Coil-Only Replacement Units: 

SEER-based Historical SWEFs and Forecasted ‘Default’ Efficiency 

Trends for the Base Case and Standards Cases .......................................10-D-1

Figure 10-D.1.2 Split System Central Air Conditioner, Coil-Only Replacement Units: 

SEER-based Historical SWEFs and Forecasted Efficiency Trends for 

the Base Case and Standards Cases, Sensitivity Case .............................10-D-2
10-D-1

APPENDIX 10-D. EFFICIENCY TREND SENSITIVITY ANALYSIS FOR SPLIT 

SYSTEM CENTRAL AIR CONDITIONER REPLACEMENT UNITS

10-D.1 EFFICIENCY TREND

As described in Chapter 10, section 10.2.1.2 describing forecasted efficiency trends for 

central air conditioners, DOE’s approach for forecasting the efficiencies of split system central 

air conditioner coil-only replacement units assumed that few consumers would choose to 

purchase units at 15 SEER and above due to the very large additional cost to install a furnace fan 

kit. As a result, market shares of products with efficiencies of 15 SEER and greater were held 

constant or frozen. Figure 10.D.1 shows the resulting base case and standards case efficiency 

trends, referred to as the ‘default’ efficiency trends, that result from the above method of 

forecasting efficiency. 

Figure 10-D.1.1 Split System Central Air Conditioner, Coil-Only 

Replacement Units: SEER-based Historical SWEFs 

and Forecasted ‘Default’ Efficiency Trends for the 

Base Case and Standards Cases

Because the above method of forecasting air conditioner efficiency results in frozen 

market shares of products with efficiencies of 15 SEER and greater, DOE investigated an 

efficiency trend sensitivity for split system central air conditioner coil-only replacement units 

that allows migration of products to 15 SEER and above. For the base case efficiency trend, this 

method allows product to migrate from lower to higher efficiency levels at a rate consistent with 

the ‘default’ efficiency trends with one exception; product migration from efficiency levels 

10

11

12

13

14

15

16

17

18

1990 1995 2000 2005 2010 2015 2020 2025 2030 2035 2040 2045

Year

SWEF (SEER)

Base Case

CSL 1: 13.5 SEER

CSL 2: 14 SEER 

CSL 3: 14.5 SEER 

CSL 4: 15 SEER 

CSL 5: 15.5 SEER 

CSL 6: 16 SEER 

CSL 7: 16.5 SEER

CSL 8: 17 SEER

CSL 9: 18 SEER 
10-D-2

below 15 SEER to efficiency levels equal to or above 15 SEER occurs at a rate that is 80% less 

than the ‘default’ trend. The lower rate of migration is based on the high hurdle costs of 

adopting products with efficiencies of 15 SEER and above.

To develop standards case forecasted SWEFs, DOE developed growth trends for the 

candidate standard levels by first “rolling up” product market shares below the candidate 

standard level to the candidate standard level in the year that standards become effective (i.e., 

2016). For the 13.5 and 14.0 SEER candidate standard levels, products were allowed to migrate 

to the 14.5 SEER efficiency level but DOE froze the market shares of products with efficiencies 

of 15 SEER and greater to equal those under the base case. For all other candidate standard 

levels, market shares of products above the given candidate standard level were frozen at those 

market shares under the base case. 

Figure 10.D.2 shows the resulting base case and standards case efficiency trends for the 

sensitivity case, i.e., the case that allows product migration to efficiency levels greater than and 

equal to 15 SEER. 

Figure 10-D.1.2 Split System Central Air Conditioner, Coil-Only 

Replacement Units: SEER-based Historical SWEFs 

and Forecasted Efficiency Trends for the Base Case 

and Standards Cases, Sensitivity Case

13

14

15

16

17

18

19

2010 2015 2020 2025 2030 2035 2040 2045

SEER

Base

SEER 

13.5

SEER 14

SEER 

14.5

SEER 15

SEER 

15.5

SEER 16

SEER 

16.5

SEER 17

SEER 18
10-D-3

Table 10-D.1.1 provides the forecasted efficiency distribution for the base case (without 

standards) for split system coil-only replacement units. The table clearly indicates how the 

market shares of product efficiencies change over time under the sensitivity case.

Table 10-D.1.1 Split System Central Air Conditioner, Coil-Only Replacement Units: 

Base Case Efficiency Distributions and SWEFs, Sensitivity Case

Year

Market Shares by SEER Level

13 13.5 14 14.5 15 15.5 16 16.5 17 18 SWEF

2016 24.6% 48.2% 4.1% 7.4% 5.9% 2.1% 7.2% 0.5% 0.0% 0.0% 13.80

2017 20.2% 44.0% 12.0% 7.9% 6.0% 1.9% 6.3% 1.7% 0.1% 0.0% 13.88

2018 16.6% 39.7% 17.8% 9.8% 6.0% 1.8% 5.5% 2.5% 0.4% 0.0% 13.96

2019 13.6% 35.5% 21.7% 12.6% 6.2% 1.7% 4.8% 3.1% 0.8% 0.1% 14.04

2020 11.1% 31.6% 24.2% 16.1% 6.4% 1.6% 4.2% 3.4% 1.2% 0.2% 14.11

2021 9.1% 27.9% 25.5% 19.9% 6.7% 1.5% 3.8% 3.5% 1.6% 0.4% 14.19

2022 7.5% 24.5% 26.0% 23.8% 7.2% 1.5% 3.4% 3.6% 1.9% 0.7% 14.26

2023 6.1% 21.4% 25.7% 27.6% 7.8% 1.5% 3.0% 3.5% 2.2% 1.1% 14.33

2024 5.0% 18.7% 24.9% 31.2% 8.5% 1.5% 2.7% 3.4% 2.5% 1.5% 14.39

2025 4.1% 16.2% 23.8% 34.6% 9.3% 1.5% 2.5% 3.3% 2.6% 1.9% 14.46

2026 3.4% 14.1% 22.4% 37.6% 10.2% 1.6% 2.3% 3.2% 2.8% 2.4% 14.51

2027 2.8% 12.1% 20.9% 40.3% 11.2% 1.7% 2.2% 3.0% 2.8% 2.9% 14.57

2028 2.3% 10.4% 19.3% 42.6% 12.3% 1.8% 2.1% 2.9% 2.9% 3.4% 14.62

2029 1.9% 9.0% 17.7% 44.6% 13.4% 1.9% 2.1% 2.7% 2.9% 3.9% 14.67

2030 1.5% 7.7% 16.2% 46.2% 14.5% 2.0% 2.0% 2.6% 2.8% 4.4% 14.72

2031 1.3% 6.6% 14.6% 47.4% 15.6% 2.2% 2.0% 2.5% 2.8% 4.9% 14.77

2032 1.0% 5.6% 13.2% 48.3% 16.8% 2.4% 2.1% 2.4% 2.8% 5.4% 14.81

2033 0.8% 4.8% 11.8% 49.0% 17.9% 2.5% 2.1% 2.4% 2.7% 5.9% 14.85

2034 0.7% 4.1% 10.6% 49.3% 19.0% 2.7% 2.2% 2.3% 2.6% 6.4% 14.89

2035 0.6% 3.5% 9.4% 49.5% 20.1% 2.9% 2.3% 2.3% 2.6% 6.9% 14.93

2036 0.5% 3.0% 8.3% 49.4% 21.2% 3.1% 2.4% 2.3% 2.5% 7.4% 14.96

2037 0.4% 2.5% 7.4% 49.1% 22.2% 3.3% 2.5% 2.3% 2.5% 7.8% 15.00

2038 0.3% 2.1% 6.5% 48.6% 23.2% 3.5% 2.7% 2.4% 2.5% 8.3% 15.03

2039 0.3% 1.8% 5.7% 48.1% 24.1% 3.7% 2.8% 2.4% 2.4% 8.7% 15.06

2040 0.2% 1.5% 5.0% 47.4% 24.9% 3.9% 3.0% 2.5% 2.4% 9.1% 15.10

2041 0.2% 1.3% 4.4% 46.6% 25.7% 4.1% 3.2% 2.6% 2.4% 9.6% 15.13

2042 0.1% 1.1% 3.8% 45.7% 26.5% 4.3% 3.3% 2.7% 2.5% 10.0% 15.16

2043 0.1% 0.9% 3.3% 44.7% 27.2% 4.5% 3.5% 2.8% 2.5% 10.5% 15.19

2044 0.1% 0.8% 2.9% 43.7% 27.8% 4.7% 3.7% 2.9% 2.6% 10.9% 15.22

2045 0.1% 0.6% 2.5% 42.6% 28.4% 4.8% 3.9% 3.1% 2.6% 11.4% 15.25
10-D-4

10-D.2 NES AND NPV RESULTS

Table 10.D.2.1 shows the national energy savings for the TSLs analyzed for split system 

central air conditioners for the residential and commercial sector for the sensitivity case. The 

table provides the breakdown of the NES for coil-only units and blower coil units. 

Table 10-D.2.1 Split System Central Air Conditioners: Cumulative National NES Results 

from 2016-2045, Residential and Commercial Sector, Sensitivity Case

TSL

NES (quads)

Total* Coil-Only Blower Coil

1 0.097 0.081 0.017

2a 0.097 0.081 0.017

2b 0.097 0.081 0.017

3a 0.316 0.270 0.046

3b 0.316 0.270 0.046

4a 0.351 0.302 0.049

4b 0.351 0.303 0.049

5 0.316 0.270 0.046

6 1.245 1.113 0.133

7 5.838 5.109 0.729

* Reflects analysis conducted at national level. Regional values do not necessarily add up to national NES.

Table 10.D.2.2 provides the NPV for the TSLs analyzed for split system central air 

conditioners for the residential and commercial sector using a three percent and seven percent 

real discount rate, respectively. The table provides the breakdown of the NPV for coil-only units 

and blower coil units. 

Table 10-D.2.2 Split System Central Air Conditioners: Cumulative National NPV Results 

from 2016-2045, Sensitivity Case

TSL

NPV @ 3% Discount Rate* (bill 2009$) NPV @ 7% Discount Rate (bill 2009$)

Total* Coil-Only Blower Coil Total* Coil-Only Blower Coil

1 0.35 0.30 0.05 0.08 0.07 0.01

2a 0.35 0.30 0.05 0.08 0.07 0.01

2b 0.35 0.30 0.05 0.08 0.07 0.01

3a 2.14 1.92 0.22 0.77 0.71 0.06

3b 2.14 1.92 0.22 0.77 0.71 0.06

4a 2.37 2.14 0.24 0.87 0.80 0.07

4b 2.38 2.14 0.24 0.88 0.80 0.07

5 2.14 1.92 0.22 0.77 0.71 0.06

6 (5.55) (5.98) 0.44 (4.49) (4.58) 0.09

7 (64.54) (61.82) (2.72) (39.66) (37.51) (2.14)

* Reflects analysis conducted at national level. Regional values do not necessarily add up to national NPV.