8C-i

APPENDIX 8C. LIFE-CYCLE COST AND PAYBACK PERIOD RESULTS

TABLE OF CONTENTS

8C.1 LIFE-CYCLE COST & PAYBACK RESULTS FOR LIQUID-IMMERSED 

TRANSFORMERS, DESIGN LINES 1-5 ..............................................................8C-1

8C.1.1 Design Line 1 Results ..............................................................................................8C-1

8C.1.2 Design Line 2 Results ..............................................................................................8C-3

8C.1.3 Design Line 3 Results ..............................................................................................8C-5

8C.1.4 Design Line 4 Results ..............................................................................................8C-7

8C.1.5 Design Line 5 Results ..............................................................................................8C-9

8C.2 LIFE-CYCLE COST & PAYBACK RESULTS FOR LOW-VOLTAGE DRY 

TYPE TRANSFORMERS, DESIGN LINES 6-8 .................................................8C-11

8C.2.1 Design Line 6 Results ............................................................................................8C-11

8C.2.2 Design Line 7 Results ............................................................................................8C-13

8C.2.3 Design Line 8 Results ............................................................................................8C-15

8C.3 LIFE-CYCLE COST & PAYBACK RESULTS FOR MEDIUM-VOLTAGE 

DRY TYPE TRANSFORMERS, DESIGN LINES 9-13B ...................................8C-17

8C.3.4 Design Line 9 Results ............................................................................................8C-17

8C.3.5 Design Line 10 Results ..........................................................................................8C-19

8C.3.6 Design Line 11 Results ..........................................................................................8C-21

8C.3.7 Design Line 12 Results ..........................................................................................8C-23

8C.3.8 Design Line 13A Results .......................................................................................8C-25

8C.3.9 Design Line 13B Results .......................................................................................8C-27

LIST OF TABLES

Table 8C.1.1 Summary Life-Cycle Cost Results for Design Line 1 Representative 

Unit ..............................................................................................................8C-1

Table 8C.1.2 Summary Payback Period Results for Design Line 1 Representative 

Unit ..............................................................................................................8C-2

Table 8C.1.3 Summary Life-Cycle Cost Results for Design Line 2 Representative 

Unit ..............................................................................................................8C-3

Table 8C.1.4 Summary Payback Period Results for Design Line 2 Representative 

Unit ..............................................................................................................8C-4

Table 8C.1.5 Summary Life-Cycle Cost Results for Design Line 3 Representative 

Unit ..............................................................................................................8C-5

Table 8C.1.6 Summary Payback Period Results for Design Line 3 Representative 

Unit ..............................................................................................................8C-6

Table 8C.1.7 Summary Life-Cycle Cost Results for Design Line 4 Representative 

Unit ..............................................................................................................8C-7

Table 8C.1.8 Summary Payback Period Results for Design Line 4 Representative 

Unit ..............................................................................................................8C-8
8C-ii

Table 8C.1.9 Summary Life-Cycle Cost Results for Design Line 5 Representative 

Unit ..............................................................................................................8C-9

Table 8C.1.10 Summary Payback Period Results for Design Line 5 Representative 

Unit ............................................................................................................8C-10

Table 8C.2.1 Summary Life-Cycle Cost Results for Design Line 6 Representative 

Unit ............................................................................................................8C-11

Table 8C.2.2 Summary Payback Period Results for Design Line 6 Representative 

Unit ............................................................................................................8C-12

Table 8C.2.3 Summary Life-Cycle Cost Results for Design Line 7 Representative 

Unit ............................................................................................................8C-13

Table 8C.2.4 Summary Payback Period Results for Design Line 7 Representative 

Unit ............................................................................................................8C-14

Table 8C.2.5 Summary Life-Cycle Cost Results for Design Line 8 Representative 

Unit ............................................................................................................8C-15

Table 8C.2.6 Summary Payback Period Results for Design Line 8 Representative 

Unit ............................................................................................................8C-16

Table 8C.3.1 Summary Life-Cycle Cost Results for Design Line 9 Representative 

Unit ............................................................................................................8C-17

Table 8C.3.2 Summary Payback Period Results for Design Line 9 Representative 

Unit ............................................................................................................8C-18

Table 8C.3.3 Summary Life-Cycle Cost Results for Design Line 10 Representative 

Unit ............................................................................................................8C-19

Table 8C.3.4 Summary Payback Period Results for Design Line 10 Representative 

Unit ............................................................................................................8C-20

Table 8C.3.5 Summary Life-Cycle Cost Results for Design Line 11 Representative 

Unit ............................................................................................................8C-21

Table 8C.3.6 Summary Payback Period Results for Design Line 11 Representative 

Unit ............................................................................................................8C-22

Table 8C.3.7 Summary Life-Cycle Cost Results for Design Line 12 Representative 

Unit ............................................................................................................8C-23

Table 8C.3.8 Summary Payback Period Results for Design Line 12 Representative 

Unit ............................................................................................................8C-24

Table 8C.3.9 Summary Life-Cycle Cost Results for Design Line 13A Representative 

Unit ............................................................................................................8C-25

Table 8C.3.10 Summary Payback Period Results for Design Line 13A Representative 

Unit ............................................................................................................8C-26

Table 8C.3.11 Summary Life-Cycle Cost Results for Design Line 13B Representative 

Unit ............................................................................................................8C-27

Table 8C.3.12 Summary Payback Period Results for Design Line 13B Representative 

Unit ............................................................................................................8C-28

LIST OF FIGURES

Figure 8C.1.1 Design Line 1, Range of LCC Savings by Efficiency Level .......................8C-1

Figure 8C.1.2 Design Line 1, Range of Payback Periods by Efficiency Level ..................8C-2
8C-iii

Figure 8C.1.3 Design Line 2, Range of LCC Savings by Efficiency Level ......................8C-3

Figure 8C.1.4 Design Line 2, Range of Payback Periods by Efficiency Level .................8C-4

Figure 8C.1.5 Design Line 3, Range of LCC Savings by Efficiency Level ......................8C-5

Figure 8C.1.6 Design Line 3, Range of Payback Periods by Efficiency Level .................8C-6

Figure 8C.1.7 Design Line 4, Range of LCC Savings by Efficiency Level ......................8C-7

Figure 8C.1.8 Design Line 4, Range of Payback Periods by Efficiency Level .................8C-8

Figure 8C.1.9 Design Line 5, Range of LCC Savings by Efficiency Level .......................8C-9

Figure 8C.1.10 Design Line 5, Range of Payback Periods by Efficiency Level ................8C-10

Figure 8C.2.1 Design Line 6, Range of LCC Savings by Efficiency Level .....................8C-11

Figure 8C.2.2 Design Line 6, Range of Payback Periods by Efficiency Level ................8C-12

Figure 8C.2.3 Design Line 7, Range of LCC Savings by Efficiency Level .....................8C-13

Figure 8C.2.4 Design Line 7, Range of Payback Periods by Efficiency Level ................8C-14

Figure 8C.2.5 Design Line 8, Range of LCC Savings by Efficiency Level .....................8C-15

Figure 8C.2.6 Design Line 8, Range of Payback Periods by Efficiency Level ................8C-16

Figure 8C.3.1 Design Line 9, Range of LCC Savings by Efficiency Level .....................8C-17

Figure 8C.3.2 Design Line 9, Range of Payback Periods by Efficiency Level ................8C-18

Figure 8C.3.3 Design Line 10, Range of LCC Savings by Efficiency Level ...................8C-19

Figure 8C.3.4 Design Line 10, Range of Payback Periods by Efficiency Level ..............8C-20

Figure 8C.3.5 Design Line 11, Range of LCC Savings by Efficiency Level ...................8C-21

Figure 8C.3.6 Design Line 11, Range of Payback Periods by Efficiency Level ..............8C-22

Figure 8C.3.7 Design Line 12, Range of LCC Savings by Efficiency Level ...................8C-23

Figure 8C.3.8 Design Line 12, Range of Payback Periods by Efficiency Level ..............8C-24

Figure 8C.3.9 Design Line 13A, Range of LCC Savings by Efficiency Level ................8C-25

Figure 8C.3.10 Design Line 13A, Range of Payback Periods by Efficiency Level ...........8C-26

Figure 8C.3.11 Design Line 13B, Range of LCC Savings by Efficiency Level ................8C-27

Figure 8C.3.12 Design Line 13B, Range of Payback Periods by Efficiency Level ...........8C-28
8C-1

APPENDIX 8C. LIFE-CYCLE COST AND PAYBACK PERIOD RESULTS

8C.1 LIFE-CYCLE COST & PAYBACK RESULTS FOR LIQUID-IMMERSED 

TRANSFORMERS, DESIGN LINES 1-5 

8C.1.1 Design Line 1 Results

Figure 8C.1.1 Design Line 1, Range of LCC Savings by Efficiency 

Level

Table 8C.1.1 Summary Life-Cycle Cost Results for Design Line 1 Representative Unit

 

Efficiency Level

1 

(actual 

EL 

0.4) 

1 2 3 4 5 6 

Efficiency (%) 99.11 99.16 99.22 99.25 99.31 99.42 99.50

Transformers with Net Increase in LCC 

(%) 37.33 44.23 6.98 6.98 11.18 14.07 42.58

Transformers with No Impact on LCC (%) 0.17 0.17 0.17 0.17 0.00 0.00 0.00

Transformers with Net LCC Savings (%) 62.50 55.60 92.85 92.85 88.82 85.93 57.42

Mean LCC Savings ($) 83 153 696 696 618 856 365

Median LCC Savings ($) 44 53 671 671 588 765 181

-1500

-1000

-500

0

500

1000

1500

2000

2500

3000

EL0.4 EL 1 EL 2 EL 3 EL 4 EL 5 EL 6

Average LCC Savings ($)

Efficiency Level

Design Line 1 Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-2

Figure 8C.1.2 Design Line 1, Range of Payback Periods by 

Efficiency Level

Table 8C.1.2 Summary Payback Period Results for Design Line 1 Representative Unit

Efficiency Level

1 

(actual 

EL 0.4)

1 2 3 4 5 6 

Mean Payback (Years) 25.5 35.7 11.4 11.4 14.3 15.9 25.7

Median Payback (Years) 17.7 24.7 10.8 10.8 13.7 15.2 24.6

Transformers having Well Defined 

Payback (%) 81.89 91.47 99.83 99.83 99.96 100.00 99.99

Transformers having Undefined Payback 

(%) 18.11 8.53 0.17 0.17 0.04 0.00 0.01

Mean Retail Cost ($) 2,110 2,247 2,447 2,447 2,550 2,804 3,335

Mean Installation Costs ($) 2,169 2,229 2,271 2,271 2,344 2,415 2,606

Mean Operating Costs ($) 205 197 159 159 157 139 134

Mean Incremental First Cost ($) 128 326 568 568 745 1,068 1,791

Mean Operating Cost Savings ($) 6 15 52 52 55 72 77

Payback of Average Transformer 20.8 22.4 10.9 10.9 13.6 14.9 23.2

0

20

40

60

80

100

120

EL0.4 EL 1 EL 2 EL 3 EL 4 EL 5 EL 6

Average Payback Period (years)

Efficiency Level

Design Line1 Average Payback Period

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-3

8C.1.2 Design Line 2 Results

Figure 8C.1.3 Design Line 2, Range of LCC Savings by Efficiency 

Level

Table 8C.1.3 Summary Life-Cycle Cost Results for Design Line 2 Representative Unit

 

Efficiency Level

Base, 

(actual 

EL 

0.5)

1 2 3 4 5 6 7 

Efficiency (%) 98.95 99.00 99.07 99.11 99.18 99.31 99.41 99.46

Transformers with Net LCC Cost 

(%) 41.49 18.16 11.39 13.07 17.83 51.51 67.17 76.53

Transformers with No Change in 

LCC (%) 3.35 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Transformers with Net LCC 

Benefit (%) 55.16 81.84 88.61 86.93 82.17 48.49 32.83 23.47

Mean LCC Savings ($) 66 278 343 330 311 -332 -579 -792

Median LCC Savings ($) 22 260 323 317 300 -23 -301 -550

-4000

-3000

-2000

-1000

0

1000

2000

EL 0.5 EL 1 EL 2 EL 3 EL 4 EL 5 EL 6 EL 7

Average LCC Savings ($)

Efficiency Level

Design Line 2 Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-4

Figure 8C.1.4 Design Line 2, Range of Payback Periods by 

Efficiency Level

Table 8C.1.4 Summary Payback Period Results for Design Line 2 Representative Unit

 

Efficiency Level

Base, 

(actual 

EL 0.5)

1 2 3 4 5 6 7 

Mean Payback (Years) 23.1 12.9 12.7 14.7 17.3 35.0 40.5 44.4

Median Payback (Years) 5.92 9.9 11.1 13.0 15.5 24.9 31.6 36.6

Transformers having Well Defined 

Payback (%) 71.11 99.14 99.93 99.86 99.91 99.88 99.92 99.95

Transformers having Undefined 

Payback (%) 28.89 0.86 0.07 0.14 0.09 0.12 0.08 0.05

Mean Retail Cost ($) 1,288 1,437 1,480 1,530 1,598 1,846 2,052 2,577

Mean Installation Costs ($) 1636 1722 1761 1790 1859 2516 2678 2457

Mean Operating Costs ($) 144 120 115 113 109 101 97 93

Mean Incremental First Cost ($) 138 235 317 396 534 1,439 1,807 2,110

Mean Operating Cost Savings ($) 65 24 29 31 34 43 47 50

Payback of Average Transformer 2.1 9.8 11.0 13.0 15.5 33.6 38.5 42.0

0

20

40

60

80

100

120

EL 0.5 EL 1 EL 2 EL 3 EL 4 EL 5 EL 6 EL 7

Average Payback Period (years)

Efficiency Level

Design Line 2 Average Payback Period

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-5

8C.1.3 Design Line 3 Results

Figure 8C.1.5 Design Line 3, Range of LCC Savings by Efficiency 

Level

Table 8C.1.5 Summary Life-Cycle Cost Results for Design Line 3 Representative Unit

 

Efficiency Level

1 

1 

(actual 

EL 

1.1)

2 3 4 5 6 7 

Efficiency (%) 99.48 99.49 99.51 99.54 99.57 99.61 99.69 99.73

Transformers with Net Increase 

in LCC (%) 13.90 14.48 11.98 5.28 4.03 4.04 8.04 29.93

Transformers with No Impact 

on LCC (%) 1.33 1.33 1.16 0.03 0.03 0.00 0.00 0.00

Transformers with Net LCC 

Savings (%) 84.77 84.19 86.86 94.69 95.94 95.96 91.96 70.07

Mean LCC Savings ($) 2407 2709 3526 5037 5527 6942 8075 4491

Median LCC Savings ($) 1918 2174 3170 4712 5246 6715 7517 3756

-10000

-5000

0

5000

10000

15000

20000

25000

EL 1 EL 1.1 EL 2 EL 3 EL 4 EL 5 EL 6 EL 7

Average LCC Savings ($)

Efficiency Level

Design Line 3 Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-6

Figure 8C.1.6 Design Line 3, Range of Payback Periods by 

Efficiency Level

Table 8C.1.6 Summary Payback Period Results for Design Line 3 Representative Unit

Efficiency Level

1 

1 

(actual 

EL 

1.1)

2 3 4 5 6 7 

Mean Payback (Years) 11.2 11.4 8.7 7.3 7.3 7.9 12.2 22.2

Median Payback (Years) 8.3 8.5 5.8 6.4 6.5 7.2 11.0 19.1

Transformers having Well 

Defined Payback (%) 96.67 97.27 98.36 99.97 99.97 100.00 100.00 99.99

Transformers having Undefined 

Payback (%) 3.33 2.73 1.64 0.03 0.03 0.00 0.00 0.01

Mean Retail Cost ($) 8,549 8,719 8,943 9,535 9,678 10,279 12,499 15,917

Mean Installation Costs ($) 4,332 4,369 4,310 4,371 4,402 4,523 4,996 7,081

Mean Operating Costs ($) 946 923 866 780 759 693 578 523

Mean Incremental First Cost ($) 937 1,145 1,310 1,962 2,136 2,859 5,552 11,054

Mean Operating Cost Savings 

($) 144 167 223 310 330 396 512 567

Payback of Average 

Transformer 6.5 6.9 5.9 6.3 6.5 7.2 10.8 19.5

0

5

10

15

20

25

30

35

40

45

EL 1 EL 1.1 EL 2 EL 3 EL 4 EL 5 EL 6 EL 7

Average Payback Period (years)

Efficiency Level

Design Line 3 Average Payback Period

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-7

8C.1.4 Design Line 4 Results

Figure 8C.1.7 Design Line 4, Range of LCC Savings by Efficiency 

Level

Table 8C.1.7 Summary Life-Cycle Cost Results for Design Line 4 Representative Unit

 Efficiency Level

1 1.5 2 3 4 5 6 7 

Efficiency (%) 99.16 99.19 99.22 99.25 99.31 99.42 99.50 99.60

Transformers with Net Increase 

in LCC (%) 6.59 7.58 2.49 2.49 2.49 2.65 5.86 23.81

Transformers with No Impact 

on LCC (%) 0.62 0.62 0.62 0.62 0.62 0.18 0.00 0.00

Transformers with Net LCC 

Savings (%) 92.79 91.80 96.89 96.89 96.89 97.17 94.14 76.19

Mean LCC Savings ($) 977 1212 3603 3603 3603 3755 4349 2806

Median LCC Savings ($) 768 2396 3546 3546 3546 3694 4135 2396

-4000

-2000

0

2000

4000

6000

8000

10000

12000

EL 1 EL 1.5 EL 2 EL 3 EL 4 EL 5 EL 6 EL 7

Average LCC Savings ($)

Efficiency Level

Design Line 4 Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-8

Figure 8C.1.8 Design Line 4, Range of Payback Periods by 

Efficiency Level

Table 8C.1.8 Summary Payback Period Results for Design Line 4 Representative Unit

 

Efficiency Level

1 1.5 2 3 4 5 6 7 

Mean Payback (Years) 8.9 10.6 5.8 5.8 5.8 6.1 10.7 19.5

Median Payback (Years) 7.0 9.1 5.6 5.6 5.6 5.8 10.2 18.7

Transformers having Well 

Defined Payback (%) 99.38 99.38 99.38 99.38 99.38 99.82 100.00 100.00

Transformers having Undefined 

Payback (%) 0.62 0.62 0.62 0.62 0.62 0.18 0.00 0.00

Mean Retail Cost ($) 5,892 6,122 6,434 6,434 6,434 6,490 7,569 10,600

Mean Installation Costs ($) 4,095 4,112 4,202 4,202 4,202 4,233 4,606 4,709

Mean Operating Costs ($) 558 539 420 420 420 413 352 297

Mean Incremental First Cost ($) 440 688 1,090 1,090 1,090 1,177 2,630 5,764

Mean Operating Cost Savings 

($) 57 75 194 194 194 202 263 318

Payback of Average 

Transformer 7.7 9.1 5.6 5.6 5.6 5.8 10.0 18.1

0

5

10

15

20

25

30

35

EL 1 EL 1.5 EL 2 EL 3 EL 4 EL 5 EL 6 EL 7

Average Payback Period (years)

Efficiency Level

Design Line 4 Average Payback Period

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-9

8C.1.5 Design Line 5 Results

Figure 8C.1.9 Design Line 5, Range of LCC Savings by Efficiency 

Level

Table 8C.1.9 Summary Life-Cycle Cost Results for Design Line 5 Representative Unit

 Efficiency Level

1 1.5 2 3 4 5 6 

Efficiency (%) 99.48 99.49 99.51 99.54 99.57 99.61 99.69

Transformers with Net Increase in LCC 

(%) 30.50 28.30 19.89 14.76 9.83 9.05 41.91

Transformers with No Impact on LCC (%) 0.39 0.35 0.09 0.01 0.00 0.00 0.00

Transformers with Net LCC Savings (%) 69.11 71.35 80.02 85.23 90.17 90.95 58.09

Mean LCC Savings ($) 3668 4486 6852 8616 10382 12014 4619

Median LCC Savings ($) 4304 3015 6763 8095 9681 11190 3015

-30000

-20000

-10000

0

10000

20000

30000

40000

EL 1 EL 1.5 EL 2 EL 3 EL 4 EL 5 EL 6

Average LCC Savings ($)

Efficiency Level

Design Line 5 Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-10

Figure 8C.1.10 Design Line 5, Range of Payback Periods by 

Efficiency Level

Table 8C.1.10 Summary Payback Period Results for Design Line 5 Representative Unit

Efficiency Level

1 1.5 2 3 4 5 6 

Mean Payback (Years) 10.6 9.9 9.2 10.1 10.1 12.2 23.7

Median Payback (Years) 6.5 6.3 6.5 8.5 9.1 11.4 22.5

Transformers having Well Defined 

Payback (%) 91.48 92.85 97.46 99.68 100.00 100.00 100.00

Transformers having Undefined Payback 

(%) 8.52 7.15 2.54 0.32 0.00 0.00 0.00

Mean Retail Cost ($) 28,575 28,608 29,043 30,875 31,982 35,306 56,798

Mean Installation Costs ($) 8,554 8,576 8,632 8,876 9,032 9,483 9,834

Mean Operating Costs ($) 2,840 2,800 2,716 2,586 2,491 2,321 1,809

Mean Incremental First Cost ($) 3,301 3,355 3,845 5,922 7,185 10,959 32,803

Mean Operating Cost Savings ($) 457 496 581 710 805 975 1,487

Payback of Average Transformer 7.2 6.8 6.6 8.3 8.9 11.2 22.1

0

5

10

15

20

25

30

35

40

EL 1 EL 1.5 EL 2 EL 3 EL 4 EL 5 EL 6

Average Payback Period (years)

Efficiency Level

Design Line 5 Average Payback Period

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-11

8C.2 LIFE-CYCLE COST & PAYBACK RESULTS FOR LOW-VOLTAGE DRY 

TYPE TRANSFORMERS, DESIGN LINES 6-8 

8C.2.1 Design Line 6 Results

Figure 8C.2.1 Design Line 6, Range of LCC Savings by Efficiency 

Level

Table 8C.2.1 Summary Life-Cycle Cost Results for Design Line 6 Representative Unit

Efficiency Level

1 2 3 4 5 6 7 

Efficiency (%) 98.23 98.47 98.60 98.80 98.93 99.17 99.44

Transformers with Net Increase in 

LCC (%) 56.21 71.32 78.08 15.65 16.47 37.80 96.60

Transformers with Net LCC Savings 

(%) 43.59 28.68 21.92 84.35 83.53 62.20 3.40

Transformers with No Impact on 

LCC (%) 0.20 0.00 0.00 0.00 0.00 0.00 0.00

Mean LCC Savings ($) -76 -104 -182 305 325 148 -992

Median LCC Savings ($) -44 -133 -215 278 308 129 -1026

-2000

-1500

-1000

-500

0

500

1000

1500

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6 EL 7

Average LCC Savings ($)

Efficiency Level

Design Line 6 Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-12

Figure 8C.2.2 Design Line 6, Range of Payback Periods by 

Efficiency Level

Table 8C.2.2 Summary Payback Period Results for Design Line 6 Representative Unit

Efficiency Level

1 2 3 4 5 6 7 

Mean Payback (Years) 28.0 31.3 29.8 12.5 12.7 16.3 32.8

Median Payback (Years) 17.6 23.8 25.5 12.1 12.4 15.7 31.7

Transformers having Well Defined 

Payback (%) 89.76 98.86 99.93 100.00 100.00 100.00 100.00

Transformers having Undefined 

Payback (%) 10.24 1.14 0.07 0.00 0.00 0.00 0.00

Mean Retail Cost ($) 1,208 1,272 1,403 1,683 1,743 1,977 2,864

Mean Installation Costs ($) 1,202 1,305 1,369 1,026 1,059 1,164 1,490

Mean Operating Costs ($) 136 128 121 99 92 82 75

Mean Incremental First Cost ($) 275 442 638 573 667 1,006 2,220

Mean Operating Cost Savings ($) 12 20 27 49 56 65 72

Payback of Average Transformer 23.7 22.5 24.1 11.7 12.0 15.4 30.6

0

20

40

60

80

100

120

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6 EL 7

Average Payback Period (years)

Efficiency Level

Design Line 6 Average Payback Period

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-13

8C.2.2 Design Line 7 Results

Figure 8C.2.3 Design Line 7, Range of LCC Savings by Efficiency 

Level

Table 8C.2.3 Summary Life-Cycle Cost Results for Design Line 7 Representative Unit

Efficiency Level

1 2 3 4 5 6 7

Efficiency (%) 98.23 98.47 98.60 98.80 98.93 99.17 99.44

Transformers with Net Increase in 

LCC (%) 1.5 1.5 1.3 1.7 2.6 3.3 45.6

Transformers with No Impact on 

LCC (%) 0.1 0.1 0.1 0.0 0.0 0.0 0.0

Transformers with Net LCC Savings 

(%) 98.4 98.4 98.7 98.3 97.4 96.7 54.4

Mean LCC Savings ($) 1526 1526 1678 1838 2045 2280 212

Median LCC Savings ($) 1471 1471 1661 1809 1987 2250 137

-3000

-2000

-1000

0

1000

2000

3000

4000

5000

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6 EL 7

Average LCC Savings ($)

Efficiency Level

Design Line 7 Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-14

Figure 8C.2.4 Design Line 7, Range of Payback Periods by 

Efficiency Level

Table 8C.2.4 Summary Payback Period Results for Design Line 7 Representative Unit

 

Efficiency Level

1 2 3 4 5 6 7 

Mean Payback (Years) 4.1 4.1 3.8 4.3 5.6 6.6 17.4

Median Payback (Years) 3.9 3.9 3.6 4.1 5.4 6.3 16.8

Transformers having Well Defined 

Payback (%) 99.93 99.93 99.93 100.00 100.00 100.00 100.00

Transformers having Undefined 

Payback (%) 0.07 0.07 0.07 0.00 0.00 0.00 0.00

Mean Retail Cost 3,201 3,201 3,204 3,459 3,813 4,089 5,929

Mean Installation Costs ($) 1,912 1,912 1,912 1,786 1,734 1,839 2,362

Mean Operating Costs ($) 239 239 230 214 185 150 128

Mean Incremental First Cost ($) 416 416 419 548 851 1,231 3,594

Mean Operating Cost Savings ($) 108 108 117 133 162 197 219

Payback of Average Transformer 3.8 3.8 3.6 4.1 5.3 6.3 16.4

-3000

-2000

-1000

0

1000

2000

3000

4000

5000

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6 EL 7

Average LCC Savings ($)

Efficiency Level

Design Line 7 Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-15

8C.2.3 Design Line 8 Results

Figure 8C.2.5 Design Line 8, Range of LCC Savings by Efficiency 

Level

Table 8C.2.5 Summary Life-Cycle Cost Results for Design Line 8 Representative Unit

 Efficiency Level

1 2 3 4 5 6 7 

Efficiency (%) 98.80 99.02 99.14 99.25 99.32 99.44 99.58

Transformers with Net Increase in 

LCC (%) 6.50 4.70 10.42 13.30 9.01 8.96 79.34

Transformers with No Impact on 

LCC (%) 93.50 95.30 89.58 86.70 90.99 91.04 20.66

Transformers with Net LCC Savings 

(%) 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Mean LCC Savings ($) 1091 2588 2530 2724 4253 4261 -2938

Median LCC Savings ($) 984 2490 2392 2578 4128 4132 -3191

-15000

-10000

-5000

0

5000

10000

15000

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6 EL 7

Average LCC Savings ($)

Efficiency Level

Design Line 8 Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-16

Figure 8C.2.6 Design Line 8, Range of Payback Periods by 

Efficiency Level

Table 8C.2.6 Summary Payback Period Results for Design Line 8 Representative Unit

 Efficiency Level

1 2 3 4 5 6 7 

Mean Payback (Years) 8.5 8.0 10.7 11.7 10.5 10.5 23.4

Median Payback (Years) 8.0 7.7 10.2 11.3 10.1 10.1 22.5

Transformers having Well Defined 

Payback (%) 100.00 100.00 100.00 100.00 100.00 100.00 100.00

Transformers having Undefined 

Payback (%) 0.00 0.00 0.00 0.00 0.00 0.00 0.00

Mean Retail Cost ($) 7,463 8,411 9,700 10,851 11,784 11,782 19,031

Mean Installation Costs ($) 2,850 2,999 3,126 3,221 3,158 3,158 3,905

Mean Operating Costs ($) 783 638 560 477 343 343 278

Mean Incremental First Cost ($) 807 1,905 3,321 4,567 5,437 5,435 13,430

Mean Operating Cost Savings ($) 107 252 331 413 547 547 612

Payback of Average Transformer 7.6 7.6 10.0 11.1 9.9 9.9 22.0

0

5

10

15

20

25

30

35

40

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6 EL 7

Average Payback Period (years)

Efficiency Level

Design Line 8 Average Payback Period

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-17

8C.3 LIFE-CYCLE COST & PAYBACK RESULTS FOR MEDIUM-VOLTAGE 

DRY TYPE TRANSFORMERS, DESIGN LINES 9-13B

8C.3.4 Design Line 9 Results

Figure 8C.3.1 Design Line 9, Range of LCC Savings by Efficiency 

Level

Table 8C.3.1 Summary Life-Cycle Cost Results for Design Line 9 Representative Unit

 Efficiency Level

1 2 3 4 5 6 

Efficiency (%) 98.93 99.04 99.15 99.22 99.39 99.55

Transformers with Net Increase in LCC 

(%) 3.56 5.87 23.75 5.60 8.38 57.39

Transformers with Net LCC Savings 

(%) 83.17 94.13 76.25 94.40 91.62 42.61

Transformers with No Impact on LCC 

(%) 13.27 0.00 0.00 0.00 0.00 0.00

Mean LCC Savings ($) 787 1514 1464 3872 3875 -299

Median LCC Savings ($) 732 1352 1236 3681 3626 -728

-8000

-6000

-4000

-2000

0

2000

4000

6000

8000

10000

12000

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6

Average LCC Savings ($)

Efficiency Level

Design Line 9 Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-18

Figure 8C.3.2 Design Line 9, Range of Payback Periods by 

Efficiency Level

Table 8C.3.2 Summary Payback Period Results for Design Line 9 Representative Unit

 Efficiency Level

1 2 3 4 5 6 

Mean Payback (Years) 3.7 7.2 13.6 8.7 9.8 19.9

Median Payback (Years) 2.6 6.1 10.9 8.3 9.4 18.5

Transformers having Well Defined 

Payback (%) 85.38 99.98 99.92 100.00 100.00 100.00

Transformers having Undefined 

Payback (%) 14.62 0.02 0.08 0.00 0.00 0.00

Mean Pretail Price ($) 14,388 14,994 16,391 17,256 18,027 23,021

Mean Installation Costs ($) 3,295 3,311 3,435 3,674 3,806 4,431

Mean Operating Costs ($) 873 795 710 509 456 373

Mean Incremental First Cost ($) 139 760 2,282 3,386 4,289 9,907

Mean Operating Cost Savings ($) 53 131 216 417 470 553

Payback of Average Transformer 2.6 5.8 10.6 8.1 9.1 17.9

0

5

10

15

20

25

30

35

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6

Average Payback Period (years)

Efficiency Level

Design Line 9 Average Payback Period

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-19

8C.3.5 Design Line 10 Results

Figure 8C.3.3 Design Line 10, Range of LCC Savings by Efficiency 

Level

Table 8C.3.3 Summary Life-Cycle Cost Results for Design Line 10 Representative Unit

 Efficiency Level

1 2 3 4 5 6 

Efficiency (%) 99.29 99.37 99.45 99.51 99.58 99.63

Transformers with Net Increase in LCC 

(%) 0.68 17.89 46.52 63.73 70.79 88.84

Transformers with Net LCC Savings 

(%) 98.80 82.11 53.48 36.27 29.21 11.16

Transformers with No Impact on LCC 

(%) 0.52 0.00 0.00 0.00 0.00 0.00

Mean LCC Savings ($) 4604 4455 1463 -2205 -4654 -14727

Median LCC Savings ($) 4438 3911 610 -2805 -5575 -15943

-40000

-30000

-20000

-10000

0

10000

20000

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6

Average LCC Savings ($)

Efficiency Level

Design Line 10 Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-20

Figure 8C.3.4 Design Line 10, Range of Payback Periods by 

Efficiency Level

Table 8C.3.4 Summary Payback Period Results for Design Line 10 Representative Unit

 Efficiency Level

1 2 3 4 5 6 

Mean Payback (Years) 1.4 11.7 20.5 20.7 22.6 30.1

Median Payback (Years) 1.1 8.6 16.1 19.6 21.2 27.5

Transformers having Well Defined 

Payback (%) 99.42 98.87 99.81 100.00 100.00 100.00

Transformers having Undefined 

Payback (%) 0.58 1.13 0.19 0.00 0.00 0.00

Mean Pretail Price ($) 43,657 46,918 54,571 65,497 70,424 81,370

Mean Installation Costs ($) 6,416 6,834 7,441 8,036 8,390 9,104

Mean Operating Costs ($) 2,599 2,394 2,083 1,622 1,453 1,335

Mean Incremental First Cost ($) 279 3,958 12,218 23,739 29,021 40,680

Mean Operating Cost Savings ($) 269 474 785 1,246 1,416 1,533

Payback of Average Transformer 1.0 8.4 15.6 19.1 20.5 26.5

0

10

20

30

40

50

60

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6

Average Payback Period (years)

Efficiency Level

Design Line 10 Average Payback Period

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-21

8C.3.6 Design Line 11 Results

Figure 8C.3.5 Design Line 11, Range of LCC Savings by Efficiency 

Level

Table 8C.3.5 Summary Life-Cycle Cost Results for Design Line 11 Representative Unit

 Efficiency Level

1 2 3 4 5 6 

Efficiency (%) 98.81 98.94 99.06 99.13 99.32 99.50

Transformers with Net Increase in LCC 

(%) 21.85 55.29 33.20 25.89 42.44 82.65

Transformers with Net LCC Savings 

(%) 78.14 44.71 66.80 74.11 57.56 17.35

Transformers with No Impact on LCC 

(%) 0.01 0.00 0.00 0.00 0.00 0.00

Mean LCC Savings ($) 996 -155 1283 1849 879 -4166

Median LCC Savings ($) 881 -266 1210 1655 651 -4539

-15000

-10000

-5000

0

5000

10000

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6

Average LCC Savings ($)

Efficiency Level

Design Line 11 Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-22

Figure 8C.3.6 Design Line 11, Range of Payback Periods by 

Efficiency Level

Table 8C.3.6 Summary Payback Period Results for Design Line 11 Representative Unit

 Efficiency Level 

1 2 3 4 5 6 

Mean Payback (Years) 12.6 24.2 16.5 14.0 17.0 25.8

Median Payback (Years) 10.6 17.7 14.1 13.6 16.1 24.1

Transformers having Well Defined 

Payback (%) 98.86 98.02 99.98 100.00 100.00 100.00

Transformers having Undefined 

Payback (%) 1.14 1.98 0.02 0.00 0.00 0.00

Mean Pretail Price ($) 22,724 24,638 26,367 26,683 29,377 35,473

Mean Installation Costs ($) 4,030 4,326 4,306 4,296 4,622 5,206

Mean Operating Costs ($) 963 899 722 673 553 445

Mean Incremental First Cost ($) 1,342 3,553 5,261 5,568 8,587 15,267

Mean Operating Cost Savings ($) 132 196 373 422 543 650

Payback of Average Transformer 10.2 18.1 14.1 13.2 15.8 23.5

0

10

20

30

40

50

60

70

80

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6

Average Payback Period (years)

Efficiency Level

Design Line 11 Average Payback Period

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-23

8C.3.7 Design Line 12 Results

Figure 8C.3.7 Design Line 12, Range of LCC Savings by Efficiency 

Level

Table 8C.3.7 Summary Life-Cycle Cost Results for Design Line 12 Representative Unit

 Efficiency Level

1 2 3 4 5 6 7 

Efficiency (%) 99.21 99.30 99.39 99.46 99.53 99.59 99.63

Transformers with Net Increase in 

LCC (%) 7.08 7.56 23.38 17.13 24.86 50.42 85.39

Transformers with No Impact on 

LCC (%) 0.01 0.00 0.00 0.00 0.00 0.00 0.00

Transformers with Net LCC Savings 

(%) 92.91 92.44 76.62 82.87 75.14 49.58 14.61

Mean LCC Savings ($) 4537 6790 6048 8594 7858 828 -14496

Median LCC Savings ($) 4301 6414 5402 8074 7250 -163 -15669

-40000

-30000

-20000

-10000

0

10000

20000

30000

40000

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6 EL 7

Average LCC Savings ($)

Efficiency Level

Design Line 12 Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-24

Figure 8C.3.8 Design Line 12, Range of Payback Periods by 

Efficiency Level

Table 8C.3.8 Summary Payback Period Results for Design Line 12 Representative Unit

 Efficiency Level

1 2 3 4 5 6 7 

Mean Payback (Years) 7.2 9.3 13.8 12.7 14.0 18.3 26.1

Median Payback (Years) 6.0 8.5 12.7 12.3 13.3 17.4 24.7

Transformers having Well Defined 

Payback (%) 99.18 100.00 99.99 100.00 100.00 100.00 100.00

Transformers having Undefined 

Payback (%) 0.82 0.00 0.01 0.00 0.00 0.00 0.00

Mean Pretail Price ($) 57,380 60,978 68,566 71,895 76,909 86,085 101,590

Mean Installation Costs ($) 7,113 7,231 7,971 8,316 8,637 9,318 10,270

Mean Operating Costs ($) 3,057 2,718 2,281 1,929 1,662 1,481 1,376

Mean Incremental First Cost ($) 2,326 6,042 14,370 18,045 23,379 33,236 49,694

Mean Operating Cost Savings ($) 384 722 1,160 1,512 1,779 1,960 2,065

Payback of Average Transformer 6.1 8.4 12.4 11.9 13.1 17.0 24.1

0

5

10

15

20

25

30

35

40

45

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6 EL 7

Average Payback Period (years)

Efficiency Level

Design Line 12 Average Payback Period

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-25

8C.3.8 Design Line 13A Results

Figure 8C.3.9 Design Line 13A, Range of LCC Savings by 

Efficiency Level

Table 8C.3.9 Summary Life-Cycle Cost Results for Design Line 13A Representative 

Unit

 Efficiency Level

1 2 3 4 5 6 

Efficiency (%) 98.69 98.84 98.97 99.04 99.25 99.45

Transformers with Net Increase in LCC 

(%) 54.22 45.52 78.38 66.30 67.20 98.46

Transformers with Net LCC Savings 

(%) 45.76 54.48 21.62 33.70 32.80 1.54

Transformers with No Impact on LCC 

(%) 0.02 0.00 0.00 0.00 0.00 0.00

Mean LCC Savings ($) -27 311 -1592 -1019 -1430 -12053

Median LCC Savings ($) -91 154 -1766 -1292 -1660 -12367

-25000

-20000

-15000

-10000

-5000

0

5000

10000

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6

Average LCC Savings ($)

Efficiency Level

Design Line 13A Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-26

Figure 8C.3.10 Design Line 13A, Range of Payback Periods by 

Efficiency Level

Table 8C.3.10 Summary Payback Period Results for Design Line 13A Representative 

Unit

 Efficiency Level

1 2 3 4 5 6 

Mean Payback (Years) 24.5 18.3 26.1 20.9 21.0 37.3

Median Payback (Years) 16.1 16.2 23.6 20.4 20.3 35.3

Transformers having Well Defined 

Payback (%) 87.42 99.92 100.00 100.00 100.00 100.00

Transformers having Undefined 

Payback (%) 12.58 0.08 0.00 0.00 0.00 0.00

Mean Pretail Price ($) 27,902 29,552 32,891 35,577 37,918 48,703

Mean Installation Costs ($) 4,752 4,832 5,103 5,093 5,309 6,280

Mean Operating Costs ($) 1,114 996 893 708 583 491

Mean Incremental First Cost ($) 868 2,598 6,207 8,884 11,441 23,197

Mean Operating Cost Savings ($) 49 167 270 455 580 672

Payback of Average Transformer 17.9 15.6 23.0 19.5 19.7 34.5

0

20

40

60

80

100

120

EL 1 EL 2 EL 3 EL 4 EL 5 EL 6

Average Payback Period (years)

Efficiency Level

Design Line 13A Average Payback Period

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-27

8C.3.9 Design Line 13B Results

Figure 8C.3.11 Design Line 13B, Range of LCC Savings by 

Efficiency Level

Table 8C.3.11 Summary Life-Cycle Cost Results for Design Line 13B Representative 

Unit

 Efficiency Level

1 2 3 4 5 

Efficiency (%) 99.19 99.28 99.38 99.45 99.52

Transformers with Net Increase in LCC (%) 30.53 27.33 60.68 53.69 70.44

Transformers with Net LCC Savings (%) 69.27 72.67 39.32 46.31 29.56

Transformers with No Impact on LCC (%) 0.20 0.00 0.00 0.00 0.00

Mean LCC Savings ($) 2494 4346 -1501 -169 -6823

Median LCC Savings ($) 2185 3751 -2427 -1056 -7690

-40000

-30000

-20000

-10000

0

10000

20000

30000

EL 1 EL 2 EL 3 EL 4 EL 5

Average LCC Savings ($)

Efficiency Level

Design Line 13B Average LCC Savings

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average
8C-28

Figure 8C.3.12 Design Line 13B, Range of Payback Periods by 

Efficiency Level

Table 8C.3.12 Summary Payback Period Results for Design Line 13B Representative 

Unit

 Efficiency Level

1 2 3 4 5 

Mean Payback (Years) 12.0 13.3 20.7 18.6 21.4

Median Payback (Years) 4.5 12.2 19.2 18.1 20.6

Transformers having Well Defined Payback 

(%) 86.89 100.00 100.00 100.00 100.00

Transformers having Undefined Payback (%) 13.11 0.00 0.00 0.00 0.00

Mean Pretail Price ($) 72,108 80,007 91,898 103,613 116,322

Mean Installation Costs ($) 8,958 8,997 9,629 9,652 10,305

Mean Operating Costs ($) 4,219 3,661 3,261 2,515 2,111

Mean Incremental First Cost ($) 1,398 9,337 21,859 33,599 46,959

Mean Operating Cost Savings ($) 219 777 1,177 1,923 2,327

Payback of Average Transformer 6.4 12.0 18.6 17.5 20.2

0

10

20

30

40

50

60

EL 1 EL 2 EL 3 EL 4 EL 5

Average Payback Period (years)

Efficiency Level

Design Line 13B Average Payback Period

Average; Median; Box 25%-75%; Whisker 5%-95%

median

average