6C-i

APPENDIX 6C. SENSITIVITY OF LIFE-CYCLE COST AND PAYBACK PERIOD 

ANALYSIS RESULTS TO ELECTRICITY PRICES

TABLE OF CONTENTS

6C.1 INTRODUCTION .........................................................................................................6C-1

LIST OF TABLES

Table 6C.1 Effect of AEO Price Scenarios on Mean LCC Savings (2011$).............................6C-2

Table 6C.2 Effect of AEO Price Scenarios on Median LCC Savings (2011$)..........................6C-3

Table 6C.3 Effect of AEO Price Scenarios on Median PBP (years)..........................................6C-4
6C-1

APPENDIX 6C. SENSITIVITY OF LIFE-CYCLE COST AND PAYBACK PERIOD 

ANALYSIS RESULTS TO ELECTRICITY PRICES

6C.1 INTRODUCTION

For the final rule, the U.S. Department of Energy (DOE) investigated the sensitivity of 

the life-cycle cost (LCC) savings and payback period (PBP) to changes in the assumed future 

electricity. As stated in the chapter 6 of the technical support document (TSD), DOE ran the 

LCC model with electricity price scenarios that were above and below the Annual Energy 

Outlook 2011 (AEO2011) Reference Case and then compared LCC savings and PBP with 

Reference Case results. In the High Growth Case, the national average commercial sector 

electricity price is about 2.1 percent higher than the Reference Case by the year 2017, rising to 

5.3 percent higher by 2042, the last year of the LCC analysis. Conversely, in the Low Growth 

Case, the national average commercial sector electricity price is 1.1 percent below the Reference 

Case in 2017, falling to 8.5 percent below by 2042. As might be expected, higher electricity 

prices make the mean LCC savings higher and the PBP shorter than those in Reference Case. 

Conversely, LCC savings are lower and the PBP longer in the Low Growth Case than in the 

Reference Case. 

However, the differences, while noticeable, do not change the fundamental message in 

the Reference Case. Table 6C.1 compares the mean LCC savings at each efficiency level for all 

consumers affected by the rule. Mean LCC savings are positive at exactly the same efficiency 

levels as in the Reference Case. Table 6C.2 shows the median LCC savings at each efficiency 

level for those consumers affected by the final rule. In Table 6C.2, half of the consumers affected 

experience higher savings than the value shown in each cell, and half experience lower savings. 

For all of the price scenarios, in many cases more than 50 percent of affected customers would 

clearly experience LCC losses at efficiency levels above the American Society of Heating, 

Refrigerating, and Air-Conditioning Engineers (ASHRAE) baseline (median LCC savings are 

negative in these cells of Table 6C.2). The only substantive difference among the price scenarios 

is that, in the Air-Cooled < 65,000 British thermal unit per hour (Btu/h) equipment class, the 

High Growth price scenario changes the consumers affected by the rule at Efficiency Level 2 

from more than 50 percent with LCC losses to more than 50 percent with LCC savings. Table 

6C.3 shows the median PBP values for the three scenarios. The High Growth price scenario 

shortens the PBP from about 1 to 4 months, depending on the equipment class and efficiency 

level, while the Low Growth price scenario lengthens the PBP by a comparable amount.
6C-2

Table 6C.1 Effect of AEO Price Scenarios on Mean LCC Savings (2011$) 

Product Class

Reference Case Mean LCC Savings 

2011$*

High Growth Case Mean LCC Savings 

2011$*

Low Growth Case Mean LCC Savings 

2011$*

Level 1 Level 2 Level 3 Level 4 Level 1 Level 2 Level 3 Level 4 Level 1 Level 2 Level 3 Level 4

Air-Cooled < 65 kBtu 584 122 (648) (1,828) 659 211 (558) (1,708) 520 47 (723) (1,927)

Air-Cooled 65–240 

kBtu

8,535 6,378 5,894 6,474 8,917 6,701 6,234 6,901 8,217 6,109 5,611 6,118 

Air-Cooled ≥ 240 kBtu 24,709 18,947 18,146 20,871 25,714 19,785 19,016 21,955 23,871 18,251 17,424 19,970 

Water-Cooled < 65 

kBtu

5,286 7,264 7,896 10,089 5,344 7,345 7,987 10,208 5,238 7,196 7,820 9,989 

Water-Cooled 65–240 

kBtu

(774) (4,582) (11,622) (23,097) (551) (4,284) (11,241) (22,636) (958) (4,829) (11,939) (23,482)

Water-Cooled ≥ 240 

kBtu

(196) (7,906) (22,491) (46,570) 330 (7,206) (21,598) (45,490) (631) (8,487) (23,233) (47,469)

Water-Cooled w/ FE < 

65 kBtu

4,686 6,400 6,908 8,772 4,717 6,444 6,956 8,835 4,662 6,366 6,870 8,722 

Water-Cooled w/ FE 

65–240 kBtu

(4,179) (9,336) (17,987) (31,244) (4,058) (9,176) (17,783) (30,997) (4,273) (9,462) (18,147) (31,438)

Water-Cooled w/ FE ≥ 

240 kBtu

(8,064) (18,795) (36,931) (64,864) (7,778) (18,418) (36,451) (64,286) (8,287) (19,090) (37,308) (65,319)

Glycol-Cooled < 65 

kBtu

5,372 7,375 8,009 10,226 5,432 7,459 8,102 10,347 5,323 7,306 7,932 10,125 

Glycol-Cooled 65–240 

kBtu

588 (3,117) (10,236) (22,091) 872 (2,743) (9,763) (21,523) 354 (3,427) (10,629) (22,563)

Glycol-Cooled ≥ 240 

kBtu

1,633 (6,637) (22,582) (49,159) 2,281 (5,786) (21,506) (47,871) 1,098 (7,343) (23,474) (50,231)

Glycol-Cooled w/ FE 

< 65 kBtu

5,162 7,064 7,640 9,722 5,208 7,128 7,711 9,815 5,125 7,013 7,583 9,647 

Glycol-Cooled w/ FE 

65–240 kBtu

(1,652) (6,282) (14,548) (27,719) (1,432) (5,993) (14,184) (27,283) (1,829) (6,515) (14,842) (28,071)

Glycol-Cooled w/ FE 

≥ 240 kBtu

(3,338) (13,598) (31,974) (61,294) (2,834) (12,939) (31,145) (60,303) (3,742) (14,128) (32,643) (62,093)

kBtu is thousand British thermal units.

* Values in parentheses indicate LCC losses.
6C-3

Table 6C.2 Effect of AEO Price Scenarios on Median LCC Savings (2011$) 

Product Class

Reference Case Median LCC Savings 

2011$*

High Growth Case Median LCC Savings 

2011$*

Low Growth Case Median LCC Savings 

2011$*

Level 1 Level 2 Level 3 Level 4 Level 1 Level 2 Level 3 Level 4 Level 1 Level 2 Level 3 Level 4

Air-Cooled < 65 kBtu 460 (111) (794) (1,878) 530 (31) (724) (1,768) 400 (166) (847) (1,980)

Air-Cooled 65–240 

kBtu

7,758 5,282 4,478 4,942 8,152 5,560 4,762 5,340 7,424 5,016 4,252 4,614 

Air-Cooled ≥ 240 

kBtu

22,520 15,830 13,996 16,809 23,574 16,593 14,634 17,765 21,623 15,170 13,398 15,997 

Water-Cooled < 65 

kBtu

5,144 8,471 7,494 9,708 5,207 8,539 7,577 9,794 5,096 8,408 7,426 9,633 

Water-Cooled 65–240 

kBtu

(1,170) (4,796) (11,835) (23,862) (923) (4,549) (11,359) (23,297) (1,336) (4,973) (12,204) (24,302)

Water-Cooled ≥ 240 

kBtu

(1,149) (8,810) (22,569) (48,314) (591) (8,248) (21,420) (47,201) (1,531) (9,287) (23,537) (49,183)

Water-Cooled w/ FE < 

65 kBtu

4,585 7,506 6,535 8,458 4,616 7,529 6,573 8,487 4,564 7,482 6,501 8,429 

Water-Cooled w/ FE 

65–240 kBtu

(4,462) (8,539) (18,938) (32,997) (4,359) (8,444) (18,611) (32,573) (4,549) (8,612) (19,131) (33,218)

Water-Cooled w/ FE ≥ 

240 kBtu

(8,658) (17,369) (38,532) (67,834) (8,426) (17,118) (37,796) (66,905) (8,848) (17,592) (38,987) (68,596)

Glycol-Cooled < 65 

kBtu

5,229 8,582 7,597 9,808 5,293 8,646 7,679 9,890 5,179 8,522 7,527 9,726 

Glycol-Cooled 65–240 

kBtu

83 (3,702) (10,118) (22,892) 376 (3,392) (9,603) (22,327) (125) (3,977) (10,501) (23,391)

Glycol-Cooled ≥ 240 

kBtu

508 (8,038) (22,386) (51,115) 1,166 (7,251) (21,284) (49,723) (38) (8,693) (23,250) (52,160)

Glycol-Cooled w/ FE 

< 65 kBtu

5,002 8,140 7,123 9,259 5,050 8,180 7,175 9,305 4,972 8,099 7,071 9,201 

Glycol-Cooled w/ FE 

65–240 kBtu

(2,226) (6,608) (14,702) (28,421) (2,019) (6,407) (14,135) (27,871) (2,371) (6,746) (15,016) (28,770)

Glycol-Cooled w/ FE 

≥ 240 kBtu

(4,493) (14,442) (32,317) (63,274) (4,095) (13,852) (30,998) (61,685) (4,870) (14,892) (33,179) (64,074)

* Values in parentheses indicate LCC losses.
6C-4

Table 6C.3 Effect of AEO Price Scenarios on Median PBP (years) 

Product Class

Reference Case Median Payback Period 

years*

High Growth Case Median Payback Period 

years*

Low Growth Case Median Payback Period 

years*

Level 1 Level 2 Level 3 Level 4 Level 1 Level 2 Level 3 Level 4 Level 1 Level 2 Level 3 Level 4

Air-Cooled < 65 kBtu 8.6 10.3 12.2 14.6 8.3 10.0 11.9 14.2 8.7 10.4 12.4 14.8 

Air-Cooled 65–240 

kBtu

2.6 3.0 3.5 3.9 2.5 2.9 3.4 3.8 2.6 3.1 3.5 4.0 

Air-Cooled ≥ 240 kBtu 1.4 1.7 2.0 2.3 1.4 1.6 1.9 2.2 1.5 1.7 2.0 2.3 

Water-Cooled < 65 

kBtu

(21.7) (21.1) (20.5) (19.9) (21.2) (20.6) (20.0) (19.5) (22.0) (21.4) (20.8) (20.2)

Water-Cooled 65–240 

kBtu

14.2 19.9 29.3 47.0 13.7 19.1 27.9 44.2 14.5 20.3 30.0 48.4 

Water-Cooled ≥ 240 

kBtu

12.6 18.6 29.7 54.6 12.1 17.7 27.9 51.9 12.9 19.0 30.6 57.8 

Water-Cooled w/ FE < 

65 kBtu

(40.7) (39.7) (38.7) (37.7) (40.2) (39.2) (38.2) (37.3) (41.1) (40.1) (39.1) (38.1)

Water-Cooled w/ FE 

65–240 kBtu

36.8 48.1 35.8 (73.0) 35.3 49.0 35.8 (67.2) 37.3 49.3 36.9 (78.4)

Water-Cooled w/ FE ≥ 

240 kBtu

32.3 22.6 (43.7) (57.2) 31.7 26.3 (43.7) (54.3) 31.0 23.3 (46.9) (55.7)

Glycol-Cooled < 65 

kBtu

(20.5) (20.0) (19.5) (19.0) (20.0) (19.5) (19.0) (18.5) (20.8) (20.3) (19.7) (19.2)

Glycol-Cooled 65–240 

kBtu

10.9 15.5 23.0 37.5 10.5 14.8 21.9 35.3 11.1 15.8 23.6 38.7 

Glycol-Cooled ≥ 240 

kBtu

10.6 16.3 28.0 48.4 10.2 15.5 26.1 48.4 10.9 16.7 29.0 52.4 

Glycol-Cooled w/ FE 

< 65 kBtu

(28.4) (27.8) (27.1) (26.4) (27.8) (27.1) (26.5) (25.8) (28.7) (28.1) (27.4) (26.7)

Glycol-Cooled w/ FE 

65–240 kBtu

18.0 27.3 45.3 49.5 17.3 26.0 43.1 49.4 18.4 28.1 42.9 49.4 

Glycol-Cooled w/ FE 

≥ 240 kBtu

19.4 26.8 17.6 (45.0) 18.4 28.3 21.3 (44.4) 20.0 26.6 18.1 (43.7)

* Values in parentheses indicate instantaneous payback, but in this case likely indicate data problems. See TSD chapters 3 and 6 concerning the equipment classes showing negative 

PBP.