Electric plant, construction and related agreements (Tables)

12 Months Ended

Dec. 31, 2021

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, 2021 and 2020 is as follows:

	2021				2020
	(dollars in thousands)
Plant	Investment		Accumulated Depreciation		Investment		Accumulated Depreciation
In-service(1)
Owned property
Vogtle Units No. 1 & No. 2 (Nuclear – 30% ownership)	$	3,010,843	$	(1,881,324)	$	3,008,848	$	(1,845,863)
Vogtle Units No. 3 & No. 4 (Nuclear – 30% ownership)	58,199		(7,290)		57,631		(5,785)
Hatch Units No. 1 & No. 2 (Nuclear – 30% ownership)	973,682		(503,871)		952,159		(479,628)
Wansley Units No. 1 & No. 2(2) (Fossil – 30% ownership)	820,110		(649,301)		764,315		(370,177)
Scherer Unit No. 1 (Fossil – 60% ownership)	1,415,115		(638,443)		1,379,513		(569,357)
Doyle (Combustion Turbine - 100% ownership)	144,711		(120,527)		139,853		(117,005)
Rocky Mountain Units No. 1, No. 2 & No. 3 (Hydro – 75% ownership)	615,485		(284,749)		618,965		(281,763)
Hartwell (Combustion Turbine - 100% ownership)	227,834		(121,174)		227,154		(113,879)
Hawk Road (Combustion Turbine - 100% ownership)	266,149		(69,194)		263,673		(63,907)
Talbot (Combustion Turbine - 100% ownership)	300,335		(158,270)		296,398		(152,859)
Chattahoochee (Combined cycle - 100% ownership)	319,550		(166,859)		319,234		(160,194)
Effingham (Combined cycle - 100% ownership)	337,614		(112,057)		—		—
Smith (Combined cycle - 100% ownership)	672,184		(190,760)		672,358		(174,176)
Wansley (Combustion Turbine – 30% ownership)(2)	3,942		(3,889)		3,942		(3,847)
Transmission plant	102,966		(62,457)		100,344		(60,688)

Other	104,372		(62,885)		98,406		(60,904)
Property under capital lease:
Scherer Unit No. 2 (Fossil – 60% leasehold)	795,301		(532,674)		794,051		(508,262)
Total in-service	$	10,168,392	$	(5,565,724)	$	9,696,844	$	(4,968,294)
Construction work in progress
Vogtle Units No. 3 & No. 4	$	6,680,014			$	5,696,342
Environmental and other        generation improvements	99,378				87,237
Total construction work in progress	$	6,779,392			$	5,783,579

(1)Amounts include plant acquisition adjustments at December 31, 2021 of $248,000,000 and December 31, 2020 of $197,000,000.

(2)Georgia Power requested in its 2022 Integrated Resource Plan filed with the Georgia Public Service Commission (PSC) that Plant Wansley Units No. 1 and No. 2 be decertified and retired by August 31, 2022. We have received approval from our board and RUS to accelerate depreciation in anticipation of the early retirement of the plant and to create a regulatory asset for the deferral of a portion of the accelerated depreciation expense, which will be recovered over an extended period.

Schedule of Jointly Owned Utility Plants

The table below shows our project budgets and actual costs through December 31, 2021 for our share of the project.

	(in millions)
	Project Budget - No Tender		Project Budget - Tender		Actual Costs at December 31, 2021
Construction Costs (1)	$	6,459	$	6,068	$	5,483
Financing Costs	1,922		1,914		1,502
Total Costs	$	8,381	$	7,982	$	6,985
Project-Level Contingency	$	98	$	98	$	—
Oglethorpe-Level Contingency	21		20		—
Total Contingency	$	119	$	118	$	—
Totals	$	8,500	$	8,100	$	6,985
(1) Construction costs are net of $1.1 billion we received from Toshiba Corporation under a Guarantee Settlement Agreement.