XML 84 R31.htm IDEA: XBRL DOCUMENT v3.20.4
REGULATORY MATTERS (Tables)
 12 Months Ended
Dec. 31, 2020
Regulated Operations [Abstract]  
Schedule of regulatory assets
Details of regulatory assets and (liabilities) reflected in the balance sheets at December 31, 2020 and 2019 are provided in the following tables:
Southern CompanyAlabama PowerGeorgia PowerMississippi PowerSouthern Company Gas
(in millions)
At December 31, 2020
AROs(a)(s)
$5,147 $1,470 $3,457 $212 $— 
Retiree benefit plans(b)(s)
4,958 1,265 1,647 238 187 
Remaining net book value of retired assets(c)
1,183 632 527 24 — 
Deferred income tax charges(d)
801 235 531 32 — 
Environmental remediation(e)(s)
310 — 41 — 269 
Loss on reacquired debt(f)
304 47 248 6 3 
Storm damage(g)
262 — 262 — — 
Vacation pay(h)(s)
207 80 104 10 13 
Under recovered regulatory clause revenues(i)
185 58 — 52 75 
Regulatory clauses(j)
142 142 — — — 
Nuclear outage(k)
101 61 40 — — 
Long-term debt fair value adjustment(l)
92 — — — 92 
Kemper County energy facility assets, net(m)
50 — — 50 — 
Plant Daniel Units 3 and 4(n)
32 — — 32 — 
Other regulatory assets(o)
205 52 68 4 81 
Deferred income tax credits(d)
(6,016)(2,016)(2,805)(320)(847)
Other cost of removal obligations(a)
(1,999)(335)212 (194)(1,649)
Over recovered regulatory clause revenues(i)
(185)(46)(44)— (95)
Storm/property damage reserves(p)
(81)(77)— (4)— 
Customer refunds(q)
(56)(50)(6)— — 
Other regulatory liabilities(r)
(149)(37)(30)(6)(54)
Total regulatory assets (liabilities), net$5,493 $1,481 $4,252 $136 $(1,925)
Southern CompanyAlabama PowerGeorgia PowerMississippi PowerSouthern Company Gas
(in millions)
At December 31, 2019
Retiree benefit plans(b)(s)
$4,423 $1,131 $1,516 $213 $167 
AROs(a)(s)
4,381 1,043 3,119 210 — 
Remaining net book value of retired assets(c)
1,275 649 596 30 — 
Deferred income tax charges(d)
803 245 523 33 — 
Storm damage(g)
410 — 410 — — 
Environmental remediation(e)(s)
349 — 52 — 296 
Loss on reacquired debt(f)
323 52 262 6 4 
Vacation pay(h)(s)
186 72 93 9 11 
Under recovered regulatory clause revenues(i)
159 40 — 47 72 
Regulatory clauses(j)
142 142 — — — 
Long-term debt fair value adjustment(l)
107 — — — 107 
Nuclear outage(k)
105 78 27 — — 
Fuel-hedging (realized and unrealized) losses(t)
102 22 53 27 — 
Kemper County energy facility assets, net(m)
61 — — 61 — 
Plant Daniel Units 3 and 4(n)
34 — — 34 — 
Other regulatory assets(o)
127 45 23 6 53 
Deferred income tax credits(d)
(6,301)(1,960)(3,078)(358)(874)
Other cost of removal obligations(a)
(2,084)(412)156 (189)(1,606)
Customer refunds(q)
(285)(56)(229)— — 
Over recovered regulatory clause revenues(i)
(205)(112)(10)— (82)
Storm/property damage reserves(p)
(204)(150)— (55)— 
Other regulatory liabilities(r)
(70)(19)(6)(10)(22)
Total regulatory assets (liabilities), net$3,838 $810 $3,507 $64 $(1,874)
Unless otherwise noted, the following recovery and amortization periods for these regulatory assets and (liabilities) have been approved by the respective state PSC or regulatory agency:
(a)AROs and other cost of removal obligations generally are recorded over the related property lives, which may range up to 53 years for Alabama Power, 60 years for Georgia Power, 55 years for Mississippi Power, and 80 years for Southern Company Gas. AROs and cost of removal obligations will be settled and trued up following completion of the related activities. Effective January 1, 2020, Georgia Power is recovering CCR AROs, including past under recovered costs and estimated annual compliance costs, over three-year periods ending December 31, 2022, 2023, and 2024 through its Environmental Compliance Cost Recovery (ECCR) tariff, as discussed further under "Georgia Power – Rate Plans" herein. See Note 6 for additional information on AROs.
(b)Recovered and amortized over the average remaining service period, which may range up to 13 years for Alabama Power, 13 years for Georgia Power, 14 years for Mississippi Power, and 13 years for Southern Company Gas. Southern Company's balances also include amounts at SCS and Southern Nuclear that are allocated to the applicable regulated utilities. See Note 11 for additional information.
(c)Alabama Power: Primarily represents the net book value of Plant Gorgas Units 8, 9, and 10 ($585 million at December 31, 2020). Being amortized over remaining periods not exceeding 17 years (through 2037).
Georgia Power: Net book values of Plant Hammond Units 1 through 4 and Plant Branch Units 2 through 4 (totaling $503 million at December 31, 2020) are being amortized over remaining periods of between two and 15 years (between 2022 and 2035) and the net book values of Plant McIntosh Unit 1 and Plant Mitchell Unit 3 (totaling $24 million at December 31, 2020) are being amortized through 2022.
Mississippi Power: Represents net book value associated with Plant Watson and Plant Greene County. The retail and wholesale portions totaling approximately $11 million and $13 million at December 31, 2020, respectively, are being amortized over a four-year period through 2024 and a 10-year period through 2030, respectively. See "Mississippi Power – Environmental Compliance Overview Plan" herein for additional information.
(d)Deferred income tax charges are recovered and deferred income tax credits are amortized over the related property lives, which may range up to 53 years for Alabama Power, 60 years for Georgia Power, 55 years for Mississippi Power, and 80 years for Southern Company Gas. See Note 10 for additional information. Included in the deferred income tax charges are amounts ($8 million, $9 million, and $1 million for Alabama Power, Georgia Power, and Mississippi Power, respectively, at December 31, 2020) for the retiree Medicare drug subsidy, which are being recovered and amortized through 2027, 2022, and 2024 for Alabama Power, Georgia Power, and Mississippi Power, respectively. As a result of the Tax Reform Legislation, these accounts include certain deferred income tax assets and liabilities not subject to normalization, as described further below:
Alabama Power: Related amounts are being recovered and amortized ratably over the related property lives.
Georgia Power: Related amounts at December 31, 2020 include $145 million of deferred income tax assets related to CWIP for Plant Vogtle Units 3 and 4 and approximately $440 million of deferred income tax liabilities. The recovery of deferred income tax assets related to CWIP for Plant Vogtle Units 3 and 4 is expected to be determined in a future regulatory proceeding. Effective January 1, 2020, the deferred income tax liabilities are being amortized through 2022.
Mississippi Power: Related amounts at December 31, 2020 include $74 million of deferred income tax liabilities, consisting of the retail portion of $66 million being amortized over three years (through 2023) and the wholesale portion of $9 million being amortized over two years (through 2021). See "Mississippi Power – 2019 Base Rate Case" and " – Municipal and Rural Associations Tariff" herein for additional information.
Southern Company Gas: Related amounts at December 31, 2020 include $8 million of deferred income tax liabilities, which are being amortized through 2024. See "Southern Company Gas – Rate Proceedings" herein for additional information.
(e)Georgia Power is recovering $12 million annually for environmental remediation. Southern Company Gas' costs are recovered through environmental cost recovery mechanisms when the remediation work is performed. See Note 3 under "Environmental Remediation" for additional information.
(f)Recovered over either the remaining life of the original issue or, if refinanced, over the remaining life of the new issue. At December 31, 2020, the remaining amortization periods do not exceed 28 years for Alabama Power, 32 years for Georgia Power, eight years for Mississippi Power, and seven years for Southern Company Gas.
(g)Georgia Power is recovering approximately $213 million annually for storm damage. See "Georgia Power – Storm Damage Recovery" herein and Note 1 under "Storm Damage Reserves" for additional information.
(h)Recorded as earned by employees and recovered as paid, generally within one year. Includes both vacation and banked holiday pay, if applicable.
(i)Alabama Power: Balances are recorded monthly and expected to be recovered or returned within nine years. Recovery periods could change based on several factors including changes in cost estimates, load forecasts, and timing of rate adjustments. See "Alabama Power – Rate CNP PPA," " – Rate CNP Compliance," and " – Rate ECR" herein for additional information.
Georgia Power: Balances are recorded monthly and expected to be recovered or returned within two years. See "Georgia Power – Rate Plans" herein for additional information.
Mississippi Power: At December 31, 2020, $37 million is being amortized over a four-year period through March 2024 and the remaining $15 million is expected to be recovered through various rate recovery mechanisms over a period to be determined in future rate filings. See "Mississippi Power – Ad Valorem Tax Adjustment" herein for additional information.
Southern Company Gas: Balances are recorded and recovered or amortized over periods generally not exceeding five years. In addition to natural gas cost recovery mechanisms, the natural gas distribution utilities have various other cost recovery mechanisms for the recovery of costs, including those related to infrastructure replacement programs.
(j)Will be amortized concurrently with the effective date of Alabama Power's next depreciation study, which is expected to occur no later than 2023.
(k)Nuclear outage costs are deferred to a regulatory asset when incurred and amortized over a subsequent period of 18 months for Alabama Power and up to 24 months for Georgia Power. See Note 5 for additional information.
(l)Recovered over the remaining lives of the original debt issuances at acquisition, which range up to 18 years at December 31, 2020.
(m)Includes $62 million of regulatory assets and $12 million of regulatory liabilities at December 31, 2020. The retail portion includes $50 million of regulatory assets and $12 million of regulatory liabilities that are expected to be fully amortized by 2024 and 2023, respectively. The wholesale portion includes $12 million of regulatory assets that are expected to be fully amortized by 2029. See Note 3 under "Mississippi Power – Other Matters – Kemper County Energy Facility" for additional information.
(n)Represents the difference between Mississippi Power's revenue requirement for Plant Daniel Units 3 and 4 under purchase accounting and operating lease accounting, which is expected to be amortized over a period to be determined in future retail and wholesale rate filings.
(o)Except as otherwise noted, comprised of numerous immaterial components with remaining amortization periods generally not exceeding 23 years for Alabama Power, three years for Georgia Power, four years for Mississippi Power, and 20 years for Southern Company Gas at December 31, 2020. Balances at December 31, 2020 include deferred COVID-19 costs (except for Alabama Power), as discussed further under "Deferral of Incremental COVID-19 Costs" for each applicable Registrant herein. Balances for Georgia Power also include certain operations and maintenance costs associated with software and cloud computing projects for which the recovery period will be determined in its next base rate case.
(p)Amortized as related expenses are incurred. See "Alabama Power – Rate NDR" and "Mississippi Power – System Restoration Rider" herein for additional information.
(q)Primarily includes approximately $50 million and $53 million at December 31, 2020 and 2019, respectively, for Alabama Power and $110 million at December 31, 2019 for Georgia Power as a result of each company exceeding its allowed retail return range. Georgia Power's December 31, 2019 balance also includes approximately $105 million pursuant to the Georgia Power Tax Reform Settlement Agreement. Georgia Power's balances also include immaterial amounts related to refunds for transmission service customers. See "Alabama Power" and "Georgia Power – Rate Plans" herein for additional information.
(r)Comprised of numerous immaterial components with remaining amortization periods generally not exceeding 17 years for Alabama Power, 12 years for Georgia Power, three years for Mississippi Power, and 20 years for Southern Company Gas at December 31, 2020.
(s)Generally not earning a return as they are excluded from rate base or are offset in rate base by a corresponding asset or liability.
(t)Fuel-hedging assets and liabilities are recorded over the life of the underlying hedged purchase contracts. Upon final settlement, actual costs incurred are recovered through the applicable traditional electric operating company's fuel cost recovery mechanism. Purchase contracts generally do not exceed three and a half years for Alabama Power, three years for Georgia Power, and five years for Mississippi Power. Immaterial amounts at December 31, 2020 are included in other regulatory assets and liabilities.
The following table illustrates Southern Company Gas' authorized ratemaking amounts that are not recognized on its balance sheets. These amounts are primarily composed of an allowed equity rate of return on assets associated with certain regulatory infrastructure programs. These amounts will be recognized as revenues in Southern Company Gas' financial statements in the periods they are billable to customers, the majority of which will be recovered by 2025.
December 31, 2020December 31, 2019
(in millions)
Atlanta Gas Light$59 $70 
Virginia Natural Gas10 10 
Nicor Gas3 2 
Total$72 $82 
Schedule of regulatory liabilities
Details of regulatory assets and (liabilities) reflected in the balance sheets at December 31, 2020 and 2019 are provided in the following tables:
Southern CompanyAlabama PowerGeorgia PowerMississippi PowerSouthern Company Gas
(in millions)
At December 31, 2020
AROs(a)(s)
$5,147 $1,470 $3,457 $212 $— 
Retiree benefit plans(b)(s)
4,958 1,265 1,647 238 187 
Remaining net book value of retired assets(c)
1,183 632 527 24 — 
Deferred income tax charges(d)
801 235 531 32 — 
Environmental remediation(e)(s)
310 — 41 — 269 
Loss on reacquired debt(f)
304 47 248 6 3 
Storm damage(g)
262 — 262 — — 
Vacation pay(h)(s)
207 80 104 10 13 
Under recovered regulatory clause revenues(i)
185 58 — 52 75 
Regulatory clauses(j)
142 142 — — — 
Nuclear outage(k)
101 61 40 — — 
Long-term debt fair value adjustment(l)
92 — — — 92 
Kemper County energy facility assets, net(m)
50 — — 50 — 
Plant Daniel Units 3 and 4(n)
32 — — 32 — 
Other regulatory assets(o)
205 52 68 4 81 
Deferred income tax credits(d)
(6,016)(2,016)(2,805)(320)(847)
Other cost of removal obligations(a)
(1,999)(335)212 (194)(1,649)
Over recovered regulatory clause revenues(i)
(185)(46)(44)— (95)
Storm/property damage reserves(p)
(81)(77)— (4)— 
Customer refunds(q)
(56)(50)(6)— — 
Other regulatory liabilities(r)
(149)(37)(30)(6)(54)
Total regulatory assets (liabilities), net$5,493 $1,481 $4,252 $136 $(1,925)
Southern CompanyAlabama PowerGeorgia PowerMississippi PowerSouthern Company Gas
(in millions)
At December 31, 2019
Retiree benefit plans(b)(s)
$4,423 $1,131 $1,516 $213 $167 
AROs(a)(s)
4,381 1,043 3,119 210 — 
Remaining net book value of retired assets(c)
1,275 649 596 30 — 
Deferred income tax charges(d)
803 245 523 33 — 
Storm damage(g)
410 — 410 — — 
Environmental remediation(e)(s)
349 — 52 — 296 
Loss on reacquired debt(f)
323 52 262 6 4 
Vacation pay(h)(s)
186 72 93 9 11 
Under recovered regulatory clause revenues(i)
159 40 — 47 72 
Regulatory clauses(j)
142 142 — — — 
Long-term debt fair value adjustment(l)
107 — — — 107 
Nuclear outage(k)
105 78 27 — — 
Fuel-hedging (realized and unrealized) losses(t)
102 22 53 27 — 
Kemper County energy facility assets, net(m)
61 — — 61 — 
Plant Daniel Units 3 and 4(n)
34 — — 34 — 
Other regulatory assets(o)
127 45 23 6 53 
Deferred income tax credits(d)
(6,301)(1,960)(3,078)(358)(874)
Other cost of removal obligations(a)
(2,084)(412)156 (189)(1,606)
Customer refunds(q)
(285)(56)(229)— — 
Over recovered regulatory clause revenues(i)
(205)(112)(10)— (82)
Storm/property damage reserves(p)
(204)(150)— (55)— 
Other regulatory liabilities(r)
(70)(19)(6)(10)(22)
Total regulatory assets (liabilities), net$3,838 $810 $3,507 $64 $(1,874)
Unless otherwise noted, the following recovery and amortization periods for these regulatory assets and (liabilities) have been approved by the respective state PSC or regulatory agency:
(a)AROs and other cost of removal obligations generally are recorded over the related property lives, which may range up to 53 years for Alabama Power, 60 years for Georgia Power, 55 years for Mississippi Power, and 80 years for Southern Company Gas. AROs and cost of removal obligations will be settled and trued up following completion of the related activities. Effective January 1, 2020, Georgia Power is recovering CCR AROs, including past under recovered costs and estimated annual compliance costs, over three-year periods ending December 31, 2022, 2023, and 2024 through its Environmental Compliance Cost Recovery (ECCR) tariff, as discussed further under "Georgia Power – Rate Plans" herein. See Note 6 for additional information on AROs.
(b)Recovered and amortized over the average remaining service period, which may range up to 13 years for Alabama Power, 13 years for Georgia Power, 14 years for Mississippi Power, and 13 years for Southern Company Gas. Southern Company's balances also include amounts at SCS and Southern Nuclear that are allocated to the applicable regulated utilities. See Note 11 for additional information.
(c)Alabama Power: Primarily represents the net book value of Plant Gorgas Units 8, 9, and 10 ($585 million at December 31, 2020). Being amortized over remaining periods not exceeding 17 years (through 2037).
Georgia Power: Net book values of Plant Hammond Units 1 through 4 and Plant Branch Units 2 through 4 (totaling $503 million at December 31, 2020) are being amortized over remaining periods of between two and 15 years (between 2022 and 2035) and the net book values of Plant McIntosh Unit 1 and Plant Mitchell Unit 3 (totaling $24 million at December 31, 2020) are being amortized through 2022.
Mississippi Power: Represents net book value associated with Plant Watson and Plant Greene County. The retail and wholesale portions totaling approximately $11 million and $13 million at December 31, 2020, respectively, are being amortized over a four-year period through 2024 and a 10-year period through 2030, respectively. See "Mississippi Power – Environmental Compliance Overview Plan" herein for additional information.
(d)Deferred income tax charges are recovered and deferred income tax credits are amortized over the related property lives, which may range up to 53 years for Alabama Power, 60 years for Georgia Power, 55 years for Mississippi Power, and 80 years for Southern Company Gas. See Note 10 for additional information. Included in the deferred income tax charges are amounts ($8 million, $9 million, and $1 million for Alabama Power, Georgia Power, and Mississippi Power, respectively, at December 31, 2020) for the retiree Medicare drug subsidy, which are being recovered and amortized through 2027, 2022, and 2024 for Alabama Power, Georgia Power, and Mississippi Power, respectively. As a result of the Tax Reform Legislation, these accounts include certain deferred income tax assets and liabilities not subject to normalization, as described further below:
Alabama Power: Related amounts are being recovered and amortized ratably over the related property lives.
Georgia Power: Related amounts at December 31, 2020 include $145 million of deferred income tax assets related to CWIP for Plant Vogtle Units 3 and 4 and approximately $440 million of deferred income tax liabilities. The recovery of deferred income tax assets related to CWIP for Plant Vogtle Units 3 and 4 is expected to be determined in a future regulatory proceeding. Effective January 1, 2020, the deferred income tax liabilities are being amortized through 2022.
Mississippi Power: Related amounts at December 31, 2020 include $74 million of deferred income tax liabilities, consisting of the retail portion of $66 million being amortized over three years (through 2023) and the wholesale portion of $9 million being amortized over two years (through 2021). See "Mississippi Power – 2019 Base Rate Case" and " – Municipal and Rural Associations Tariff" herein for additional information.
Southern Company Gas: Related amounts at December 31, 2020 include $8 million of deferred income tax liabilities, which are being amortized through 2024. See "Southern Company Gas – Rate Proceedings" herein for additional information.
(e)Georgia Power is recovering $12 million annually for environmental remediation. Southern Company Gas' costs are recovered through environmental cost recovery mechanisms when the remediation work is performed. See Note 3 under "Environmental Remediation" for additional information.
(f)Recovered over either the remaining life of the original issue or, if refinanced, over the remaining life of the new issue. At December 31, 2020, the remaining amortization periods do not exceed 28 years for Alabama Power, 32 years for Georgia Power, eight years for Mississippi Power, and seven years for Southern Company Gas.
(g)Georgia Power is recovering approximately $213 million annually for storm damage. See "Georgia Power – Storm Damage Recovery" herein and Note 1 under "Storm Damage Reserves" for additional information.
(h)Recorded as earned by employees and recovered as paid, generally within one year. Includes both vacation and banked holiday pay, if applicable.
(i)Alabama Power: Balances are recorded monthly and expected to be recovered or returned within nine years. Recovery periods could change based on several factors including changes in cost estimates, load forecasts, and timing of rate adjustments. See "Alabama Power – Rate CNP PPA," " – Rate CNP Compliance," and " – Rate ECR" herein for additional information.
Georgia Power: Balances are recorded monthly and expected to be recovered or returned within two years. See "Georgia Power – Rate Plans" herein for additional information.
Mississippi Power: At December 31, 2020, $37 million is being amortized over a four-year period through March 2024 and the remaining $15 million is expected to be recovered through various rate recovery mechanisms over a period to be determined in future rate filings. See "Mississippi Power – Ad Valorem Tax Adjustment" herein for additional information.
Southern Company Gas: Balances are recorded and recovered or amortized over periods generally not exceeding five years. In addition to natural gas cost recovery mechanisms, the natural gas distribution utilities have various other cost recovery mechanisms for the recovery of costs, including those related to infrastructure replacement programs.
(j)Will be amortized concurrently with the effective date of Alabama Power's next depreciation study, which is expected to occur no later than 2023.
(k)Nuclear outage costs are deferred to a regulatory asset when incurred and amortized over a subsequent period of 18 months for Alabama Power and up to 24 months for Georgia Power. See Note 5 for additional information.
(l)Recovered over the remaining lives of the original debt issuances at acquisition, which range up to 18 years at December 31, 2020.
(m)Includes $62 million of regulatory assets and $12 million of regulatory liabilities at December 31, 2020. The retail portion includes $50 million of regulatory assets and $12 million of regulatory liabilities that are expected to be fully amortized by 2024 and 2023, respectively. The wholesale portion includes $12 million of regulatory assets that are expected to be fully amortized by 2029. See Note 3 under "Mississippi Power – Other Matters – Kemper County Energy Facility" for additional information.
(n)Represents the difference between Mississippi Power's revenue requirement for Plant Daniel Units 3 and 4 under purchase accounting and operating lease accounting, which is expected to be amortized over a period to be determined in future retail and wholesale rate filings.
(o)Except as otherwise noted, comprised of numerous immaterial components with remaining amortization periods generally not exceeding 23 years for Alabama Power, three years for Georgia Power, four years for Mississippi Power, and 20 years for Southern Company Gas at December 31, 2020. Balances at December 31, 2020 include deferred COVID-19 costs (except for Alabama Power), as discussed further under "Deferral of Incremental COVID-19 Costs" for each applicable Registrant herein. Balances for Georgia Power also include certain operations and maintenance costs associated with software and cloud computing projects for which the recovery period will be determined in its next base rate case.
(p)Amortized as related expenses are incurred. See "Alabama Power – Rate NDR" and "Mississippi Power – System Restoration Rider" herein for additional information.
(q)Primarily includes approximately $50 million and $53 million at December 31, 2020 and 2019, respectively, for Alabama Power and $110 million at December 31, 2019 for Georgia Power as a result of each company exceeding its allowed retail return range. Georgia Power's December 31, 2019 balance also includes approximately $105 million pursuant to the Georgia Power Tax Reform Settlement Agreement. Georgia Power's balances also include immaterial amounts related to refunds for transmission service customers. See "Alabama Power" and "Georgia Power – Rate Plans" herein for additional information.
(r)Comprised of numerous immaterial components with remaining amortization periods generally not exceeding 17 years for Alabama Power, 12 years for Georgia Power, three years for Mississippi Power, and 20 years for Southern Company Gas at December 31, 2020.
(s)Generally not earning a return as they are excluded from rate base or are offset in rate base by a corresponding asset or liability.
(t)Fuel-hedging assets and liabilities are recorded over the life of the underlying hedged purchase contracts. Upon final settlement, actual costs incurred are recovered through the applicable traditional electric operating company's fuel cost recovery mechanism. Purchase contracts generally do not exceed three and a half years for Alabama Power, three years for Georgia Power, and five years for Mississippi Power. Immaterial amounts at December 31, 2020 are included in other regulatory assets and liabilities.
Schedule of revised cost and schedule
Georgia Power's approximate proportionate share of the remaining estimated capital cost to complete Plant Vogtle Units 3 and 4 by the expected in-service dates of November 2021 and November 2022, respectively, is as follows:
(in billions)
Base project capital cost forecast(a)(b)
$8.5 
Construction contingency estimate0.2 
Total project capital cost forecast(a)(b)
8.7 
Net investment as of December 31, 2020(b)
(7.2)
Remaining estimate to complete(a)
$1.5 
(a)Excludes financing costs expected to be capitalized through AFUDC of approximately $246 million, of which $93 million had been accrued through December 31, 2020.
(b)Net of $1.7 billion received from Toshiba under the Guarantee Settlement Agreement and approximately $188 million in related customer refunds.
Public utilities general disclosures
In December 2019, the Georgia PSC voted to approve the 2019 ARP, under which Georgia Power increased its rates on January 1, 2020. On December 15, 2020, the Georgia PSC approved tariff adjustments effective January 1, 2021. Details of tariff adjustments are provided in the table below:
Tariff20202021
(in millions)
Traditional base$— $120 
ECCR(*)
318 2 
DSM12 (15)
MFF12 4 
Total$342 $111 
(*)    Effective January 1, 2020, CCR AROs are being recovered through the ECCR tariff.
The following table provides regulatory information for Southern Company Gas' natural gas distribution utilities:
Nicor GasAtlanta Gas LightVirginia Natural GasChattanooga Gas
Authorized ROE(a)
9.73%10.25%9.50%9.80%
Weather normalization mechanisms(b)
üü
Decoupled, including straight-fixed-variable rates(c)
üüü
Regulatory infrastructure program rates(d)
üü
Bad debt rider(e)
üüü
Energy efficiency plan(f)
üü
Annual base rate adjustment mechanism(g)
üü
Year of last base rate case decision2019201920172018
(a)Represents the authorized ROE, or the mid-point of the authorized ROE range, at December 31, 2020.
(b)Designed to help stabilize operating results by allowing recovery of costs in the event of unseasonal weather, but are not direct offsets to the potential impacts on earnings of weather and customer consumption.
(c)Allows for recovery of fixed customer service costs separately from assumed natural gas volumes used by customers and provides a benchmark level of revenue for recovery.
(d)Programs that update or expand distribution systems and LNG facilities.
(e)The recovery (refund) of bad debt expense over (under) an established benchmark expense. The gas portion of bad debt expense is recovered through purchased gas adjustment mechanisms. Nicor Gas also has a rider to recover the non-gas portion of bad debt expense.
(f)Recovery of costs associated with plans to achieve specified energy savings goals.
(g)Regulatory mechanism allowing annual adjustments to base rates up or down based on authorized ROE and/or ROE range.
The following table and discussions provide updates on the infrastructure replacement programs and capital projects at the natural gas distribution utilities at December 31, 2020. These programs are risk-based and designed to update and replace cast iron, bare steel, and mid-vintage plastic materials or expand Southern Company Gas' distribution systems to improve reliability and meet operational flexibility and growth.
UtilityProgramRecoveryExpenditures in 2020Expenditures Since Project InceptionPipe
Installed Since
Project Inception		Scope of
Program		Program DurationLast
Year of Program
(in millions)(miles)(miles)(years)
Nicor Gas
Investing in Illinois(*)
Rider$389 $2,101 996 1,450 92023
Virginia Natural GasSteps to Advance Virginia's Energy (SAVE)Rider49 293 413 770 132024
Total$438 $2,394 1,409 2,220 
(*)Includes replacement of pipes, compressors, and transmission mains along with other improvements such as new meters. Scope of program miles is an estimate and subject to change.