Property, Plant And Equipment

12 Months Ended

Dec. 31, 2024

Property, Plant and Equipment [Abstract]

(5) PROPERTY, PLANT, AND EQUIPMENT

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


	2024				2023				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	$	1,508.5		39	$	1,492.8		40	32	44
Electric transmission		793.7		48		737.4		48	42	51
Electric distribution		1,238.5		47		1,146.9		47	45	50
Integrated Generation		724.0		30		720.0		30	19	38
Plant acquisition adjustment (a)		4.9		32		4.9		32	32	32
General		306.6		26		291.7		27	23	27
Total electric plant in service		4,576.2				4,393.7
Construction work-in-progress		259.4				123.1
Total electric plant		4,835.6				4,516.8
Less accumulated depreciation		(1,280.3	)			(1,207.7	)
Electric plant net of accumulated depreciation	$	3,555.3			$	3,309.1

____________________

(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 6 years remaining.


	2024				2023				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	$	21.6		43	$	21.0		45	24	45
Gas transmission		817.5		58		759.5		58	32	73
Gas distribution		3,107.3		57		2,860.0		57	48	61
Cushion gas - not depreciable (a)		52.1		N/A		58.2		N/A	N/A	N/A
Storage		78.8		42		71.4		42	36	48
General		599.4		22		571.8		22	20	24
Total gas plant in service		4,676.7				4,341.9
Construction work-in-progress		43.5				39.2
Total gas plant		4,720.2				4,381.1
Less accumulated depreciation		(656.3	)			(588.3	)
Gas plant net of accumulated depreciation	$	4,063.9			$	3,792.8

____________________

(a)

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


	2024			2023				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	$	0.4	10	$	5.7		10	4	21
Construction work-in-progress		10.3			13.6
Total gross property, plant and equipment		10.7			19.3
Less accumulated depreciation		—			(1.9	)
Total net of accumulated depreciation	$	10.7		$	17.4