Electric plant, construction and related agreements (Tables)

12 Months Ended

Dec. 31, 2019

Property, Plant and Equipment [Abstract]

Summary of plant investments and related accumulated depreciation

A summary of our plant investments and related accumulated depreciation as of December 31, 2019 and 2018 is as follows:


	2019						2018
	(dollars in thousands)
Plant	Investment		Accumulated Depreciation		Investment		Accumulated Depreciation
In-service⁽¹⁾
Owned property
Vogtle Units No. 1 & No. 2 (Nuclear – 30% ownership)	$	2,989,693	$	(1,815,258)	$	2,975,727	$	(1,775,569)
Vogtle Units No. 3 & No. 4 (Nuclear – 30% ownership)	56,991		(4,956)		55,861		(3,479)
Hatch Units No. 1 & No. 2 (Nuclear – 30% ownership)	934,567		(462,063)		910,259		(441,240)
Wansley Units No. 1 & No. 2 (Fossil – 30% ownership)	749,971		(360,014)		655,618		(311,606)
Scherer Unit No. 1 (Fossil – 60% ownership)	1,284,508		(545,908)		1,222,538		(442,840)
Doyle (Combustion Turbine - 100% ownership)	137,513		(113,259)		137,133		(109,509)
Rocky Mountain Units No. 1, No. 2 & No. 3 (Hydro – 75% ownership)	618,939		(270,058)		618,621		(258,359)
Hartwell (Combustion Turbine - 100% ownership)	226,316		(110,008)		226,156		(105,540)
Hawk Road (Combustion Turbine - 100% ownership)	260,494		(67,065)		254,925		(75,308)
Talbot (Combustion Turbine - 100% ownership)	294,809		(144,847)		293,638		(136,007)
Chattahoochee (Combined cycle - 100% ownership)	317,210		(150,805)		315,463		(141,279)
Smith (Combined cycle - 100% ownership)	655,106		(195,638)		648,464		(179,486)
Wansley (Combustion Turbine – 30% ownership)	3,887		(3,738)		3,887		(3,626)
Transmission plant	96,198		(59,096)		95,861		(56,973)
Other	96,522		(57,826)		93,503		(56,193)
Property under capital lease:
Scherer Unit No. 2 (Fossil – 60% leasehold)	789,991		(472,486)		776,316		(447,391)
Total in-service	$	9,512,715	$	(4,833,025)	$	9,283,970	$	(4,544,405)
Construction work in progress
Vogtle Units No. 3 & No. 4	$	4,617,654			$	3,600,631
Environmental and other generation improvements	198,357				263,146
Other	885				2,265
Total construction work in progress	$	4,816,896			$	3,866,042

(1)Amounts include plant acquisition adjustments at December 31, 2019 and 2018 of $197,000,000.