Property, Plant, and Equipment (Tables)

12 Months Ended

Dec. 31, 2020

Property, Plant and Equipment [Abstract]

PP&E by Classification, Summary of Depreciation and Amortization

The following is a summary of Property, plant, and equipment by classification as of December 31:

	2020		2019
Property, plant, and equipment	(In millions)
DTE Electric
Zero carbon generation
Nuclear	$	3,295	$	3,022
Renewables	1,817		1,362
Fossil and other generation	8,031		7,644
Distribution	10,354		9,715
Other	2,674		2,536
Total DTE Electric	26,171		24,279
DTE Gas
Distribution	4,517		4,164
Storage	576		570
Transmission and other	1,341		1,244
Total DTE Gas	6,434		5,978
Non-utility and other
Gas Storage and Pipelines	3,981		3,524
Power and Industrial Projects	1,194		1,108
Other	217		183
Non-utility and other	5,392		4,815
Total DTE Energy	37,997		35,072
Accumulated depreciation and amortization
DTE Electric
Zero carbon generation
Nuclear	(373)		(344)
Renewables	(295)		(243)
Fossil and other generation	(3,014)		(2,873)
Distribution	(2,686)		(2,553)
Other	(682)		(693)
Total DTE Electric	(7,050)		(6,706)
DTE Gas
Distribution	(1,215)		(1,334)
Storage	(146)		(172)
Transmission and other	(403)		(409)
Total DTE Gas	(1,764)		(1,915)
Non-utility and other
Gas Storage and Pipelines	(511)		(459)
Power and Industrial Projects	(619)		(604)
Other	(84)		(71)
Non-utility and other	(1,214)		(1,134)
Total DTE Energy	(10,028)		(9,755)
Net DTE Energy Property, plant, and equipment	$	27,969	$	25,317
Net DTE Electric Property, plant, and equipment	$	19,121	$	17,573

The following is a summary of Depreciation and amortization expense for DTE Energy:

	2020		2019		2018
	(In millions)
Property, plant, and equipment	$	1,120	$	997	$	878
Regulatory assets and liabilities	245		227		212
Intangible assets	71		33		27
Other	7		6		7
	$	1,443	$	1,263	$	1,124

The following is a summary of Depreciation and amortization expense for DTE Electric:

	2020		2019		2018
	(In millions)
Property, plant, and equipment	$	831	$	748	$	652
Regulatory assets and liabilities	207		193		179
Other	5		5		5
	$	1,043	$	946	$	836

Schedule of AFUDC and Capitalized Interest Rates

The AFUDC and capitalized interest rates were as follows for the years ended December 31:

	2020		2019		2018
DTE Electric AFUDC	5.47	%	5.43	%	5.41	%
DTE Gas AFUDC	5.56	%	5.56	%	5.71	%
Non-regulated businesses capitalized interest	3.90	%	4.00	%	4.00	%

Schedule of AFUDC and Interest Capitalized

The following is a summary of AFUDC and interest capitalized for the years ended December 31:

	2020		2019		2018
DTE Energy	(In millions)
Allowance for debt funds used during construction and interest capitalized	$	22	$	15	$	15
Allowance for equity funds used during construction	25		24		28
Total	$	47	$	39	$	43

	2020		2019		2018
DTE Electric	(In millions)
Allowance for debt funds used during construction	$	10	$	10	$	9
Allowance for equity funds used during construction	23		22		19
Total	$	33	$	32	$	28

Schedule of Utility Property, Plant, and Equipment

The average estimated useful life for each major class of utility Property, plant, and equipment as of December 31, 2020 follows:

	Estimated Useful Lives in Years
Utility	Generation	Distribution	Storage
DTE Electric	32	38	N/A
DTE Gas	N/A	49	58

Schedule of Capitalized Software

The following balances for capitalized software relate to DTE Energy:

	Year Ended December 31,
	2020		2019		2018
	(In millions)
Amortization expense of capitalized software	$	129	$	123	$	108
Gross carrying value of capitalized software	$	866	$	906
Accumulated amortization of capitalized software	$	432	$	520

The following balances for capitalized software relate to DTE Electric:

	Year Ended December 31,
	2020		2019		2018
	(In millions)
Amortization expense of capitalized software	$	118	$	112	$	101
Gross carrying value of capitalized software	$	756	$	811
Accumulated amortization of capitalized software	$	363	$	462