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PROPERTY, PLANT, AND EQUIPMENT - Property, Plant and Equipment (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Electric utilities: |  |
Generation | $ 53,803 | $ 52,179
Transmission | 13,406 | 12,879
Distribution | 22,236 | 20,958
General/other | 5,423 | 5,072
Electric utilities' plant in service | 94,868 | 91,088
Southern Company Gas: |  |
Natural gas distribution utilities transportation and distribution | 15,714 | 14,610
Storage facilities | 1,315 | 1,752
Other | 1,851 | 1,249
Southern Company Gas plant in service | 18,880 | 17,611
Other plant in service | 1,844 | 1,817
Total plant in service | 115,592 | 110,516
Alabama Power |  |
Electric utilities: |  |
Generation | 16,631 | 16,201
Transmission | 5,334 | 5,033
Distribution | 8,643 | 8,248
General/other | 2,527 | 2,334
Electric utilities' plant in service | 33,135 | 31,816
Southern Company Gas: |  |
Natural gas distribution utilities transportation and distribution | 0 | 0
Storage facilities | 0 | 0
Other | 0 | 0
Southern Company Gas plant in service | 0 | 0
Other plant in service | 0 | 0
Total plant in service | 33,135 | 31,816
Georgia Power |  |
Electric utilities: |  |
Generation | 19,184 | 18,675
Transmission | 7,132 | 6,951
Distribution | 12,437 | 11,622
General/other | 2,579 | 2,434
Electric utilities' plant in service | 41,332 | 39,682
Southern Company Gas: |  |
Natural gas distribution utilities transportation and distribution | 0 | 0
Storage facilities | 0 | 0
Other | 0 | 0
Southern Company Gas plant in service | 0 | 0
Other plant in service | 0 | 0
Total plant in service | 41,332 | 39,682
Mississippi Power |  |
Electric utilities: |  |
Generation | 2,791 | 2,819
Transmission | 900 | 856
Distribution | 1,156 | 1,088
General/other | 259 | 248
Electric utilities' plant in service | 5,106 | 5,011
Southern Company Gas: |  |
Natural gas distribution utilities transportation and distribution | 0 | 0
Storage facilities | 0 | 0
Other | 0 | 0
Southern Company Gas plant in service | 0 | 0
Other plant in service | 0 | 0
Total plant in service | 5,106 | 5,011
Southern Power |  |
Electric utilities: |  |
Generation | 14,551 | 13,872
Transmission | 0 | 0
Distribution | 0 | 0
General/other | 34 | 32
Electric utilities' plant in service | 14,585 | 13,904
Southern Company Gas: |  |
Natural gas distribution utilities transportation and distribution | 0 | 0
Storage facilities | 0 | 0
Other | 0 | 0
Southern Company Gas plant in service | 0 | 0
Other plant in service | 0 | 0
Total plant in service | 14,585 | 13,904
Southern Company Gas |  |
Electric utilities: |  |
Generation | 0 | 0
Transmission | 0 | 0
Distribution | 0 | 0
General/other | 0 | 0
Electric utilities' plant in service | 0 | 0
Southern Company Gas: |  |
Natural gas distribution utilities transportation and distribution | 15,714 | 14,610
Storage facilities | 1,315 | 1,752
Other | 1,851 | 1,249
Southern Company Gas plant in service | 18,880 | 17,611
Other plant in service | 0 | 0
Total plant in service | $ 18,880 | $ 17,611

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