v3.25.4
Property, Plant And Equipment
12 Months Ended
Dec. 31, 2025
Property, Plant and Equipment [Abstract]  
Property, Plant and Equipment

(5) PROPERTY, PLANT, AND EQUIPMENT

 

Property, plant, and equipment at December 31 consisted of the following:

 

2025

2024

Lives

Electric Utilities

Property, Plant and Equipment

 

Weighted Average Useful Life

Property, Plant and Equipment

 

Weighted Average Useful Life

Minimum

Maximum

 

(dollars in millions, life in years)

(in years)

Electric plant:

 

 

 

 

 

 

 

 

Production

$

1,545.4

 

40

$

1,508.5

 

39

32

45

Electric transmission

 

1,052.3

 

48

 

793.7

 

48

44

51

Electric distribution

 

1,347.3

 

49

 

1,238.5

 

47

45

55

Integrated Generation

 

727.3

 

30

 

724.0

 

30

19

38

Plant acquisition adjustment (a)

 

4.9

 

32

 

4.9

 

32

32

32

General

 

310.2

 

25

 

306.6

 

26

16

28

Total electric plant in service

 

4,987.4

 

 

 

4,576.2

 

 

 

 

Construction work-in-progress

 

270.1

 

 

 

259.4

 

 

 

 

Total electric plant

 

5,257.5

 

 

 

4,835.6

 

 

 

 

Less accumulated depreciation

 

(1,366.5

)

 

 

(1,280.3

)

 

 

 

Electric plant net of accumulated depreciation

$

3,891.0

 

 

$

3,555.3

 

 

 

 

____________________

(a)
The plant acquisition adjustment, which relates to the acquisition of our ownership interest in Wyodak Plant, is included in rate base and is being recovered with 5 years remaining.

 

2025

2024

Lives

Gas Utilities

Property, Plant and Equipment

 

Weighted Average Useful Life

Property, Plant and Equipment

 

Weighted Average Useful Life

Minimum

Maximum

 

(dollars in millions, life in years)

(in years)

Gas plant:

 

 

 

 

 

 

 

 

Production

$

26.3

 

44

$

21.6

 

43

24

45

Gas transmission

 

860.0

 

57

 

817.5

 

58

32

73

Gas distribution

 

3,414.3

 

57

 

3,107.3

 

57

48

61

Cushion gas - not depreciable (a)

 

51.4

 

N/A

 

52.1

 

N/A

N/A

N/A

Storage

 

83.6

 

42

 

78.8

 

42

36

47

General

 

587.2

 

22

 

599.4

 

22

20

25

Total gas plant in service

 

5,022.8

 

 

 

4,676.7

 

 

 

 

Construction work-in-progress

 

50.5

 

 

 

43.5

 

 

 

 

Total gas plant

 

5,073.3

 

 

 

4,720.2

 

 

 

 

Less accumulated depreciation

 

(744.4

)

 

 

(656.3

)

 

 

 

Gas plant net of accumulated depreciation

$

4,328.9

 

 

$

4,063.9

 

 

 

 

____________________

(a)
Depreciation of Cushion Gas is determined by the respective regulatory jurisdiction in which the Cushion Gas resides.

 

2025

2024

Lives

Corporate

Property, Plant and Equipment

 

Weighted Average Useful Life

Property, Plant and Equipment

 

Weighted Average Useful Life

Minimum

Maximum

 

(dollars in millions, life in years)

(in years)

Total plant in service

$

0.3

 

N/A

$

0.4

 

N/A

N/A

N/A

Construction work-in-progress

 

13.8

 

 

 

10.3

 

 

 

 

Total gross property, plant and equipment

 

14.1

 

 

 

10.7

 

 

 

 

Less accumulated depreciation

 

0.2

 

 

 

 

 

 

 

Total net of accumulated depreciation

$

14.3

 

 

$

10.7