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

 

 

 

 

 

Historical Timeline

Fiscal YearFiled
2025Feb 11, 2026Showing above
2024Feb 12, 2025
2023Feb 14, 2024
2022Feb 14, 2023
2021Feb 15, 2022
2020Feb 26, 2021
2019Feb 14, 2020
2018Feb 19, 2019
2017Feb 26, 2018
2016Feb 27, 2017
2015Feb 25, 2016

About PP&E Disclosures

The PP&E disclosure details a company's physical asset base — land, buildings, machinery, and equipment — along with the depreciation methods and useful life assumptions that determine how these costs flow through the income statement. Capitalization policy thresholds reveal management's judgment on the boundary between expense and asset, directly affecting both reported earnings and asset values.

Key signals: changes in estimated useful lives or depreciation methods can materially shift reported earnings without any operational change. Compare capital expenditures against depreciation expense — when capex consistently trails depreciation, the asset base may be aging and underinvested. Watch for large asset impairments or write-downs that signal overvalued carrying amounts. Asset retirement obligations reveal future environmental or decommissioning costs that are often underappreciated. Compare PP&E intensity (PP&E-to-revenue) against industry peers to assess capital efficiency and competitive positioning.