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    Table of Contents                                Index to Financial Statements
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 10-Q
QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d)
OF THE SECURITIES EXCHANGE ACT OF 1934
For the quarterly period ended March 31, 2024
OR
TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)
OF THE SECURITIES EXCHANGE ACT OF 1934
For the transition period from           to            
Commission
File Number
Registrant,
State of Incorporation,
Address and Telephone Number
I.R.S. Employer
Identification No.
1-3526The Southern Company58-0690070
(A Delaware Corporation)
30 Ivan Allen Jr. Boulevard, N.W.
Atlanta, Georgia 30308
(404) 506-5000
1-3164Alabama Power Company63-0004250
(An Alabama Corporation)
600 North 18th Street
Birmingham, Alabama 35203
(205) 257-1000
1-6468Georgia Power Company58-0257110
(A Georgia Corporation)
241 Ralph McGill Boulevard, N.E.
Atlanta, Georgia 30308
(404) 506-6526
001-11229Mississippi Power Company64-0205820
(A Mississippi Corporation)
2992 West Beach Boulevard
Gulfport, Mississippi 39501
(228) 864-1211
001-37803Southern Power Company58-2598670
(A Delaware Corporation)
30 Ivan Allen Jr. Boulevard, N.W.
Atlanta, Georgia 30308
(404) 506-5000
1-14174Southern Company Gas58-2210952
(A Georgia Corporation)
Ten Peachtree Place, N.E.
Atlanta, Georgia 30309
(404) 584-4000


    Table of Contents                                Index to Financial Statements
Securities registered pursuant to Section 12(b) of the Act:
RegistrantTitle of Each ClassTrading
Symbol(s)
Name of Each Exchange
on Which Registered
The Southern CompanyCommon Stock, par value $5 per shareSONew York Stock Exchange
(NYSE)
The Southern CompanySeries 2017B 5.25% Junior Subordinated Notes due 2077SOJCNYSE
The Southern CompanySeries 2020A 4.95% Junior Subordinated Notes due 2080SOJDNYSE
The Southern CompanySeries 2020C 4.20% Junior Subordinated Notes due 2060SOJENYSE
The Southern CompanySeries 2021B 1.875% Fixed-to-Fixed Reset Rate Junior Subordinated Notes due 2081SO 81NYSE
Georgia Power CompanySeries 2017A 5.00% Junior Subordinated Notes due 2077GPJANYSE
Southern Power CompanySeries 2016B 1.850% Senior Notes due 2026SO/26ANYSE
Indicate by check mark whether the registrants (1) have filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrants were required to file such reports), and (2) have been subject to such filing requirements for the past 90 days. Yes þ No ¨
Indicate by check mark whether the registrants have submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrants were required to submit such files). Yes þ No ¨
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.
RegistrantLarge Accelerated FilerAccelerated
Filer
Non-accelerated FilerSmaller
Reporting
Company
Emerging
Growth
Company
The Southern CompanyX
Alabama Power CompanyX
Georgia Power CompanyX
Mississippi Power CompanyX
Southern Power CompanyX
Southern Company GasX
If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes No þ (Response applicable to all registrants.)
RegistrantDescription of Common Stock
Shares Outstanding at
March 31, 2024
The Southern CompanyPar Value $5 Per Share1,093,426,111 
Alabama Power CompanyPar Value $40 Per Share30,537,500 
Georgia Power CompanyWithout Par Value9,261,500 
Mississippi Power CompanyWithout Par Value1,121,000 
Southern Power CompanyPar Value $0.01 Per Share1,000 
Southern Company GasPar Value $0.01 Per Share100 
This combined Form 10-Q is separately filed by The Southern Company, Alabama Power Company, Georgia Power Company, Mississippi Power Company, Southern Power Company, and Southern Company Gas. Information contained herein relating to any individual registrant is filed by such registrant on its own behalf. Each registrant makes no representation as to information relating to the other registrants.
2

    Table of Contents                                Index to Financial Statements
TABLE OF CONTENTS
  Page
PART I—FINANCIAL INFORMATION
Item 1.
Item 2.
Item 3.
Item 4.
PART II—OTHER INFORMATION
Item 1.
Item 1A.
Item 2.Unregistered Sales of Equity Securities and Use of ProceedsInapplicable
Item 3.Defaults Upon Senior SecuritiesInapplicable
Item 4.Mine Safety DisclosuresInapplicable
Item 5.
Item 6.
3

    Table of Contents                                Index to Financial Statements

DEFINITIONS
TermMeaning
2022 ARPAlternate Rate Plan approved by the Georgia PSC in 2022 for Georgia Power for the years 2023 through 2025
AFUDCAllowance for funds used during construction
Alabama PowerAlabama Power Company
Amended and Restated Loan Guarantee AgreementLoan guarantee agreement entered into by Georgia Power with the DOE in 2014, as amended and restated in March 2019, under which the proceeds of borrowings may be used to reimburse Georgia Power for Eligible Project Costs incurred in connection with its construction of Plant Vogtle Units 3 and 4
AROAsset retirement obligation
Atlanta Gas LightAtlanta Gas Light Company, a wholly-owned subsidiary of Southern Company Gas
CCRCoal combustion residuals
Chattanooga GasChattanooga Gas Company, a wholly-owned subsidiary of Southern Company Gas
COD
Commercial operation date
Cooperative EnergyElectric generation and transmission cooperative in Mississippi
COVID-19The novel coronavirus disease declared a pandemic by the World Health Organization and the Centers for Disease Control and Prevention in March 2020
CWIPConstruction work in progress
DaltonCity of Dalton, Georgia, an incorporated municipality in the State of Georgia, acting by and through its Board of Water, Light, and Sinking Fund Commissioners
Dalton PipelineA pipeline facility in Georgia in which Southern Company Gas has a 50% undivided ownership interest
DOEU.S. Department of Energy
ELGEffluent limitations guidelines
Eligible Project CostsCertain costs of construction relating to Plant Vogtle Units 3 and 4 that are eligible for financing under the loan guarantee program established under Title XVII of the Energy Policy Act of 2005
EPAU.S. Environmental Protection Agency
EPC ContractorWestinghouse and its affiliate, WECTEC Global Project Services Inc.; the former engineering, procurement, and construction contractor for Plant Vogtle Units 3 and 4
FCCFederal Communications Commission
FERCFederal Energy Regulatory Commission
FFBFederal Financing Bank
First Solar
First Solar Electric, LLC
FitchFitch Ratings, Inc.
Form 10-K
Annual Report on Form 10-K of Southern Company, Alabama Power, Georgia Power, Mississippi Power, Southern Power, and Southern Company Gas for the year ended December 31, 2023, as applicable
GAAPU.S. generally accepted accounting principles
Georgia PowerGeorgia Power Company
GHGGreenhouse gas
Guarantee Settlement AgreementThe June 9, 2017 settlement agreement between the Vogtle Owners and Toshiba related to certain payment obligations of the EPC Contractor guaranteed by Toshiba
Heating Degree DaysA measure of weather, calculated when the average daily temperatures are less than 65 degrees Fahrenheit
Heating SeasonThe period from November through March when Southern Company Gas' natural gas usage and operating revenues are generally higher
HLBVHypothetical liquidation at book value
IGCCIntegrated coal gasification combined cycle, the technology originally approved for Mississippi Power's Kemper County energy facility
IICIntercompany Interchange Contract
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DEFINITIONS
(continued)
TermMeaning
Illinois CommissionIllinois Commerce Commission
IRPIntegrated resource plan
ITCInvestment tax credit
KWHKilowatt-hour
LIFOLast-in, first-out
LTSALong-term service agreement
MEAG PowerMunicipal Electric Authority of Georgia
Mississippi PowerMississippi Power Company
mmBtuMillion British thermal units
Moody'sMoody's Investors Service, Inc.
MRAMunicipal and Rural Associations
MWMegawatt
natural gas distribution utilitiesSouthern Company Gas' natural gas distribution utilities (Nicor Gas, Atlanta Gas Light, Virginia Natural Gas, and Chattanooga Gas)
NCCRGeorgia Power's Nuclear Construction Cost Recovery tariff
NDRAlabama Power's Natural Disaster Reserve
Nicor GasNorthern Illinois Gas Company, a wholly-owned subsidiary of Southern Company Gas
N/MNot meaningful
NRCU.S. Nuclear Regulatory Commission
OCIOther comprehensive income
OPCOglethorpe Power Corporation (an electric membership corporation)
PEPMississippi Power's Performance Evaluation Plan
PowerSecurePowerSecure, Inc., a wholly-owned subsidiary of Southern Company
PPAPower purchase agreements, as well as, for Southern Power, contracts for differences that provide the owner of a renewable facility a certain fixed price for the electricity sold to the grid
Prudency Stipulation
Stipulated agreement among Georgia Power, the staff of the Georgia PSC, and certain intervenors modifying Georgia Power's August 2023 application to adjust retail rates to include reasonable and prudent Plant Vogtle Units 3 and 4 costs and approved by the Georgia PSC in December 2023
PSCPublic Service Commission
PTCProduction tax credit
Rate CNPAlabama Power's Rate Certificated New Plant, consisting of Rate CNP New Plant, Rate CNP Compliance, Rate CNP PPA, and Rate CNP Depreciation
Rate ECRAlabama Power's Rate Energy Cost Recovery
RegistrantsSouthern Company, Alabama Power, Georgia Power, Mississippi Power, Southern Power Company, and Southern Company Gas
ROEReturn on equity
S&PS&P Global Ratings, a division of S&P Global Inc.
SCSSouthern Company Services, Inc., the Southern Company system service company and a wholly-owned subsidiary of Southern Company
SECU.S. Securities and Exchange Commission
SEGCOSouthern Electric Generating Company, 50% owned by each of Alabama Power and Georgia Power
SNGSouthern Natural Gas Company, L.L.C., a pipeline system in which Southern Company Gas has a 50% ownership interest
SOFRSecured Overnight Financing Rate
Southern CompanyThe Southern Company
Southern Company GasSouthern Company Gas and its subsidiaries
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DEFINITIONS
(continued)
TermMeaning
Southern Company Gas Capital
Southern Company Gas Capital Corporation, a wholly-owned subsidiary of Southern Company Gas
Southern Company power poolThe operating arrangement whereby the integrated generating resources of the traditional electric operating companies and Southern Power (excluding subsidiaries) are subject to joint commitment and dispatch in order to serve their combined load obligations
Southern Company systemSouthern Company, the traditional electric operating companies, Southern Power, Southern Company Gas, SEGCO, Southern Nuclear, SCS, Southern Communications Services, Inc., PowerSecure, and other subsidiaries
Southern HoldingsSouthern Company Holdings, Inc., a wholly-owned subsidiary of Southern Company
Southern NuclearSouthern Nuclear Operating Company, Inc., a wholly-owned subsidiary of Southern Company
Southern PowerSouthern Power Company and its subsidiaries
SouthStarSouthStar Energy Services, LLC (a Marketer), a wholly-owned subsidiary of Southern Company Gas
SP SolarSP Solar Holdings I, LP, a limited partnership indirectly owning substantially all of Southern Power's solar and battery energy storage facilities, in which Southern Power has a 67% ownership interest
SP WindSP Wind Holdings II, LLC, a holding company owning a portfolio of eight operating wind facilities, in which Southern Power is the controlling partner in a tax equity arrangement
SRRMississippi Power's System Restoration Rider, a tariff for retail property damage cost recovery and reserve
Subsidiary RegistrantsAlabama Power, Georgia Power, Mississippi Power, Southern Power, and Southern Company Gas
ToshibaToshiba Corporation, the parent company of Westinghouse
traditional electric operating companiesAlabama Power, Georgia Power, and Mississippi Power
VIEVariable interest entity
Virginia Natural GasVirginia Natural Gas, Inc., a wholly-owned subsidiary of Southern Company Gas
Vogtle OwnersGeorgia Power, OPC, MEAG Power, and Dalton
WACOGWeighted average cost of gas
WestinghouseWestinghouse Electric Company LLC
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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION
This Quarterly Report on Form 10-Q contains forward-looking statements. Forward-looking statements include, among other things, statements concerning regulated rates, the strategic goals for the business, customer and sales growth, economic conditions, including inflation, cost recovery and other rate actions, current and proposed environmental regulations and related compliance plans and estimated expenditures, pending or potential litigation matters, access to sources of capital, financing activities, completion dates and costs of construction projects, matters related to the abandonment of the Kemper IGCC, filings with state and federal regulatory authorities, and estimated construction plans and expenditures. In some cases, forward-looking statements can be identified by terminology such as "may," "will," "could," "would," "should," "expects," "plans," "anticipates," "believes," "estimates," "projects," "predicts," "potential," or "continue" or the negative of these terms or other similar terminology. There are various factors that could cause actual results to differ materially from those suggested by the forward-looking statements; accordingly, there can be no assurance that such indicated results will be realized. These factors include:

the impact of recent and future federal and state regulatory changes, including tax, environmental, and other laws and regulations to which Southern Company and its subsidiaries are subject, as well as changes in application of existing laws and regulations;
the extent and timing of costs and legal requirements related to CCR;
current and future litigation or regulatory investigations, proceedings, or inquiries, including litigation and other disputes related to the Kemper County energy facility and Plant Vogtle Units 3 and 4;
the effects, extent, and timing of the entry of additional competition in the markets in which Southern Company's subsidiaries operate, including from the development and deployment of alternative energy sources;
variations in demand for electricity and natural gas;
available sources and costs of natural gas and other fuels and commodities;
the ability to complete necessary or desirable pipeline expansion or infrastructure projects, limits on pipeline capacity, public and policymaker support for such projects, and operational interruptions to natural gas distribution and transmission activities;
transmission constraints;
the ability to control costs and avoid cost and schedule overruns during the development, construction, and operation of facilities or other projects due to challenges which include, but are not limited to, changes in labor costs, availability, and productivity; challenges with the management of contractors or vendors; subcontractor performance; adverse weather conditions; shortages, delays, increased costs, or inconsistent quality of equipment, materials, and labor; contractor or supplier delay; the impacts of inflation; delays due to judicial or regulatory action; nonperformance under construction, operating, or other agreements; operational readiness, including specialized operator training and required site safety programs; engineering or design problems or any remediation related thereto; design and other licensing-based compliance matters; challenges with start-up activities, including major equipment failure, or system integration; and/or operational performance; challenges related to pandemic health events; continued public and policymaker support for projects; environmental and geological conditions; delays or increased costs to interconnect facilities to transmission grids; and increased financing costs as a result of changes in interest rates or as a result of project delays;
legal proceedings and regulatory approvals and actions related to past, ongoing, and proposed construction projects, including PSC approvals and FERC and NRC actions;
the ability to construct facilities in accordance with the requirements of permits and licenses, to satisfy any environmental performance standards and the requirements of tax credits and other incentives, and to integrate facilities into the Southern Company system upon completion of construction;
investment performance of the employee and retiree benefit plans and nuclear decommissioning trust funds;
advances in technology, including the pace and extent of development of low- to no-carbon energy and battery energy storage technologies and negative carbon concepts;
performance of counterparties under ongoing renewable energy partnerships and development agreements;
state and federal rate regulations and the impact of pending and future rate cases and negotiations, including rate actions relating to ROE, equity ratios, additional generating capacity, and fuel and other cost recovery mechanisms;
the ability to successfully operate the traditional electric operating companies' and SEGCO's generation, transmission, and distribution facilities, Southern Power's generation facilities, and Southern Company Gas' natural gas distribution and storage facilities and the successful performance of necessary corporate functions;
the inherent risks involved in operating nuclear generating facilities;
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    Table of Contents                                Index to Financial Statements
CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION
(continued)
the inherent risks involved in generation, transmission, and distribution of electricity and transportation and storage of natural gas, including accidents, explosions, fires, mechanical problems, discharges or releases of toxic or hazardous substances or gases, and other environmental risks;
the performance of projects undertaken by the non-utility businesses and the success of efforts to invest in and develop new opportunities;
internal restructuring or other restructuring options that may be pursued;
potential business strategies, including acquisitions or dispositions of assets or businesses, which cannot be assured to be completed or beneficial to Southern Company or its subsidiaries;
the ability of counterparties of Southern Company and its subsidiaries to make payments as and when due and to perform as required;
the ability to obtain new short- and long-term contracts with wholesale customers;
the direct or indirect effect on the Southern Company system's business resulting from cyber intrusion or physical attack and the threat of cyber and physical attacks;
global and U.S. economic conditions, including impacts from geopolitical conflicts, recession, inflation, interest rate fluctuations, and financial market conditions, and the results of financing efforts;
access to capital markets and other financing sources;
changes in Southern Company's and any of its subsidiaries' credit ratings;
the ability of the traditional electric operating companies to obtain additional generating capacity (or sell excess generating capacity) at competitive prices;
catastrophic events such as fires, earthquakes, explosions, floods, tornadoes, hurricanes and other storms, droughts, pandemic health events, political unrest, wars, or other similar occurrences;
the direct or indirect effects on the Southern Company system's business resulting from incidents affecting the U.S. electric grid, natural gas pipeline infrastructure, or operation of generating or storage resources;
impairments of goodwill or long-lived assets;
the effect of accounting pronouncements issued periodically by standard-setting bodies; and
other factors discussed elsewhere herein and in other reports (including the Form 10-K) filed by the Registrants from time to time with the SEC.
The Registrants expressly disclaim any obligation to update any forward-looking statements.
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PART I
Item 1. Financial Statements (Unaudited).
 Page
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    Table of Contents                                Index to Financial Statements

THE SOUTHERN COMPANY AND SUBSIDIARY COMPANIES
CONDENSED CONSOLIDATED STATEMENTS OF INCOME (UNAUDITED)
 
 For the Three Months Ended March 31,
 20242023
 (in millions)
Operating Revenues:
Retail electric revenues$3,941 $3,599 
Wholesale electric revenues571 599 
Other electric revenues199 190 
Natural gas revenues (includes alternative revenue programs of $34 and $12, respectively)
1,707 1,875 
Other revenues228 217 
Total operating revenues6,646 6,480 
Operating Expenses:
Fuel996 1,050 
Purchased power198 242 
Cost of natural gas605 898 
Cost of other sales131 127 
Other operations and maintenance1,472 1,440 
Depreciation and amortization1,145 1,111 
Taxes other than income taxes396 394 
Total operating expenses4,943 5,262 
Operating Income1,703 1,218 
Other Income and (Expense):
Allowance for equity funds used during construction58 65 
Earnings from equity method investments45 48 
Interest expense, net of amounts capitalized(665)(582)
Other income (expense), net153 147 
Total other income and (expense)(409)(322)
Earnings Before Income Taxes1,294 896 
Income taxes223 97 
Consolidated Net Income1,071 799 
Net loss attributable to noncontrolling interests(58)(63)
Consolidated Net Income Attributable to
   Southern Company
$1,129 $862 
Common Stock Data:
Earnings per share -
Basic$1.03 $0.79 
Diluted$1.03 $0.79 
Average number of shares of common stock outstanding (in millions)
Basic1,094 1,091 
Diluted1,100