Property Plant and Equipment Property Plant and Equipment (Tables)

12 Months Ended

Dec. 31, 2018

Property, Plant and Equipment [Line Items]

Schedule of Jointly Owned Utility Plants

tility subsidiaries’ jointly owned assets as of Dec. 31, 2018:

(Millions of Dollars)	Plant in Service		Accumulated Depreciation		CWIP		Percent Owned
NSP-Minnesota
Electric Generation:
Sherco Unit 3	$	604	$	415	$	1	59	%
Sherco Common Facilities	145		100		1		80
Other	5		4		—		59
Electric Transmission:
CapX2020 Transmission	960		73		2		51
Other	11		2		—		50
Total NSP-Minnesota	$	1,725	$	594	$	4

(Millions of Dollars)	Plant in Service		Accumulated Depreciation		CWIP		Percent Owned
NSP-Wisconsin
Electric Transmission:
La Crosse, WI to Madison, WI	$	175	$	2	$	—	37	%
CapX2020 Transmission	169		15		2		81
Total NSP-Wisconsin	$	344	$	17	$	2

(Millions of Dollars)	Plant in Service		Accumulated Depreciation		CWIP		Percent Owned
PSCo
Electric Generation:
Hayden Unit 1	$	153	$	76	$	—	76	%
Hayden Unit 2	149		68		—		37
Hayden Common Facilities	41		21		—		53
Craig Units 1 and 2	81		40		—		10
Craig Common Facilities	39		21		—		7
Comanche Unit 3	886		130		—		67
Comanche Common Facilities	28		3		—		82
Electric Transmission:
Transmission and other facilities	183		63		1		Various
Gas Transportation:
Rifle, CO to Avon, CO	22		7		—		60
Gas Transportation Compressor	8		1		—		50
Total PSCo	$	1,590	$	430	$	1

Each company’s share of operating expenses and construction expenditures are included in the applicable utility accounts. Respective owners are responsible for providing their own financing.

Public Utility Property, Plant, and Equipment

Major classes of property, plant and equipment:

(Millions of Dollars)	Dec. 31, 2018			Dec. 31, 2017
Property, plant and equipment
Electric plant	$	41,472		$	39,016
Natural gas plant	6,210			5,800
Common and other property	2,154			2,013
Plant to be retired (a)	322			11
CWIP	2,091			2,087
Total property, plant and equipment	52,249			48,927
Less accumulated depreciation	(15,659		)	(15,000		)
Nuclear fuel	2,771			2,697
Less accumulated amortization	(2,417		)	(2,295		)
	$	36,944		$	34,329

^(a)  In 2018, the CPUC approved early retirement of PSCo’s Comanche Units 1 and 2 in approximately 2022 and 2025, respectively. PSCo also expects Craig Unit 1 to be retired early in 2025.  Amounts are presented net of accumulated depreciation.

NSP-Minnesota

Property, Plant and Equipment [Line Items]

Schedule of Jointly Owned Utility Plants

(Millions of Dollars)	Plant in Service		Accumulated Depreciation		CWIP		Percent Owned
NSP-Minnesota
Electric Generation:
Sherco Unit 3	$	604	$	415	$	1	59	%
Sherco Common Facilities	145		100		1		80
Other	5		4		—		59
Electric Transmission:
CapX2020 Transmission	960		73		2		51
Other	11		2		—		50
Total NSP-Minnesota	$	1,725	$	594	$	4

NSP-Wisconsin

Property, Plant and Equipment [Line Items]

Schedule of Jointly Owned Utility Plants

(Millions of Dollars)	Plant in Service		Accumulated Depreciation		CWIP		Percent Owned
NSP-Wisconsin
Electric Transmission:
La Crosse, WI to Madison, WI	$	175	$	2	$	—	37	%
CapX2020 Transmission	169		15		2		81
Total NSP-Wisconsin	$	344	$	17	$	2

PSCo

Property, Plant and Equipment [Line Items]

Schedule of Jointly Owned Utility Plants

(Millions of Dollars)	Plant in Service		Accumulated Depreciation		CWIP		Percent Owned
PSCo
Electric Generation:
Hayden Unit 1	$	153	$	76	$	—	76	%
Hayden Unit 2	149		68		—		37
Hayden Common Facilities	41		21		—		53
Craig Units 1 and 2	81		40		—		10
Craig Common Facilities	39		21		—		7
Comanche Unit 3	886		130		—		67
Comanche Common Facilities	28		3		—		82
Electric Transmission:
Transmission and other facilities	183		63		1		Various
Gas Transportation:
Rifle, CO to Avon, CO	22		7		—		60
Gas Transportation Compressor	8		1		—		50
Total PSCo	$	1,590	$	430	$	1