Property, Plant and Equipment

12 Months Ended

Dec. 31, 2020

Property, Plant and Equipment [Abstract]

Property, Plant and Equipment

Property, Plant and Equipment

SCE's property, plant and equipment included in the consolidated balance sheets is composed of the following:

	December 31,
(in millions)	2020		2019
Distribution	$	28,663	$	26,929
Transmission	15,669		14,720
Generation	3,709		3,664
General plant and other	5,129		4,583
Accumulated depreciation	(10,681)		(9,958)
	42,489		39,938
Construction work in progress	5,033		4,131
Nuclear fuel, at amortized cost	131		129
Total utility property, plant and equipment	$	47,653	$	44,198

Capitalized Software Costs

SCE capitalizes costs incurred during the application development stage of internal use software projects to property, plant and equipment. SCE amortizes capitalized software costs ratably over the expected lives of the software, primarily ranging from 5 to 7 years and commencing upon operational use. Capitalized software costs, included in general plant and other above, were $1.2 billion and $1.0 billion at December 31, 2020 and 2019, respectively, and accumulated amortization was $0.6 billion and $0.4 billion, at December 31, 2020 and 2019, respectively. Amortization expense for capitalized software was $218 million, $190 million and $198 million in 2020, 2019 and 2018, respectively. At December 31, 2020, amortization expense is estimated to be $213 million, $168 million, $136 million, $82 million and $30 million for 2021 through 2025, respectively.

Jointly Owned Utility Projects

SCE owns undivided interests in transmission and generating assets for which each participant provides its own financing. SCE's proportionate share of these assets is reflected in the consolidated balance sheets and included in the above table. SCE's proportionate share of expenses for each project is reflected in the consolidated statements of income.

The following is SCE's investment in each asset as of December 31, 2020:

(in millions)	Plant in Service		Construction Work in Progress		Accumulated Depreciation		Nuclear Fuel (at amortized cost)		Net Book Value		Ownership Interest
Transmission systems:
Eldorado	$	324	$	74	$	39	$	—	$	359	79	%
Pacific Intertie	346		—		74		—		272		50	%
Generating station:
Palo Verde (nuclear)	2,113		53		1,609		131		688		16	%
Total	$	2,783	$	127	$	1,722	$	131	$	1,319

In addition, SCE has ownership interests in jointly owned power poles with other companies.