Regulatory Matters

12 Months Ended

Dec. 31, 2018

Regulated Operations [Abstract]

Regulatory Matters

REGULATORY MATTERS

Southern Company

Regulatory Assets and Liabilities

Regulatory assets and (liabilities) reflected in the consolidated balance sheets of Southern Company at December 31, 2018 and 2017 relate to:

	2018			2017			Note
	(in millions)
Retiree benefit plans	$	3,658		$	3,931		(a,p)
Asset retirement obligations-asset	2,933			1,133			(b,p)
Deferred income tax charges	799			814			(b,o)
Property damage reserves-asset	416			333			(c)
Under recovered regulatory clause revenues	407			317			(d)
Environmental remediation-asset	366			511			(e,p)
Loss on reacquired debt	346			223			(f)
Remaining net book value of retired assets	211			306			(g)
Vacation pay	182			183			(h,p)
Long-term debt fair value adjustment	121			138			(i)
Deferred PPA charges	—			119			(j,p)
Other regulatory assets	581			625			(k)
Deferred income tax credits	(6,455		)	(7,261		)	(b,o)
Other cost of removal obligations	(2,297		)	(2,684		)	(b)
Customer refunds	(293		)	(188		)	(n)
Property damage reserves-liability	(76		)	(135		)	(l)
Over recovered regulatory clause revenues	(47		)	(155		)	(d)
Other regulatory liabilities	(132		)	(104		)	(m)
Total regulatory assets (liabilities), net	$	720		$	(1,894	)

Note: Unless otherwise noted, the recovery and amortization periods for these regulatory assets and (liabilities) are approved by the respective PSC or regulatory agency and are as follows:

(a) Recovered and amortized over the average remaining service period which may range up to 15 years. See Note 11 for additional information.

(b) Asset retirement and other cost of removal obligations are recorded, deferred income tax assets are recovered, and deferred income tax liabilities are amortized over the related property lives, which may range up to 80 years. Asset retirement and removal liabilities will be settled and trued up following completion of the related activities. Included in the deferred income tax assets is $28 million for the retiree Medicare drug subsidy, which is being recovered and amortized through 2027.

(c) Through 2019, Georgia Power is recovering approximately $30 million annually for storm damage, which is expected to be adjusted in the Georgia Power 2019 Base Rate Case. See "Georgia Power – Storm Damage Recovery" herein for additional information.

(d) Recorded and recovered or amortized over periods generally not exceeding 10 years.

(e) Recovered through environmental cost recovery mechanisms when the remediation is performed or the work is performed.

(f) Recovered over either the remaining life of the original issue or, if refinanced, over the remaining life of the new issue, which may range up to 50 years.

(g) Amortized over periods not exceeding eight years.

(h) Recorded as earned by employees and recovered as paid, generally within one year. This includes both vacation and banked holiday pay.

(i) Recovered over the remaining life of the original debt issuances, which range up to 20 years. For additional information see Note 15 under "Southern Company Merger with Southern Company Gas."

(j) Related to Gulf Power and reclassified as assets held for sale at December 31, 2018. See Note 15 under "Southern Company's Sale of Gulf Power" for information regarding the sale of Gulf Power.

(k) Comprised of numerous immaterial components including nuclear outage, fuel-hedging losses, cancelled construction projects, building and generating plant leases, property tax, and other miscellaneous assets. These costs are recorded and recovered or amortized over periods generally not exceeding 50 years.

(l) Amortized as storm restoration and potential reliability-related expenses are incurred.

(m) Comprised of numerous components including retiree benefit plans, fuel-hedging gains, AROs, and other liabilities that are recorded and recovered or amortized over periods not exceeding 20 years.

(n) At December 31, 2018, represents amounts accrued and outstanding for refund, including approximately $109 million as a result of Alabama Power's 2018 retail return exceeding the allowed range, approximately $55 million pursuant to the Georgia Power Tax Reform Settlement Agreement, and approximately $100 million, subject to review and approval by the Georgia PSC, as a result of Georgia Power's 2018 retail ROE exceeding the allowed retail ROE range. See "Alabama Power – Rate RSE" and "Georgia Power – Rate Plans" herein for additional information.

(o) As a result of the Tax Reform Legislation, these accounts include certain deferred income tax assets and liabilities not subject to normalization. The recovery and amortization of these amounts will be determined in future rate proceedings. See "Georgia Power," "Mississippi Power," and "Southern Company Gas" herein and Note 10 for additional information.

(p) Not earning a return as offset in rate base by a corresponding asset or liability.

Gulf Power

On January 1, 2019, Southern Company completed its sale of Gulf Power to NextEra Energy. See Note 15 under "Southern Company's Sale of Gulf Power" for additional information.

In accordance with a Florida PSC-approved settlement agreement, Gulf Power's rates effective for the first billing cycle in July 2017 increased by approximately $54 million annually (2017 Gulf Power Rate Case Settlement), including a $62 million increase in base revenues, less an $8 million purchased power capacity cost recovery clause credit. The 2017 Rate Case Settlement Agreement also resulted in a $32.5 million write-down of Gulf Power's ownership of Plant Scherer Unit 3, which was recorded in the first quarter 2017.

As a continuation of the 2017 Gulf Power Rate Case Settlement Agreement, on March 26, 2018, the Florida PSC approved a stipulation and settlement agreement addressing Gulf Power's retail revenue requirement effects of the Tax Reform Legislation (Gulf Power Tax Reform Settlement Agreement). Beginning in April 1, 2018, the Gulf Power Tax Reform Settlement Agreement resulted in annual reductions of approximately $18 million to Gulf Power's base rates and approximately $16 million to Gulf Power's environmental cost recovery rates and a one-time refund of approximately $69 million for the retail portion of unprotected (not subject to normalization) deferred tax liabilities, which was credited to customers through Gulf Power's fuel cost recovery rates over the remainder of 2018.

Alabama Power

Regulatory Assets and Liabilities

Regulatory assets and (liabilities) reflected in the balance sheets of Alabama Power at December 31, 2018 and 2017 relate to:

	2018			2017			Note
	(in millions)
Retiree benefit plans	$	947		$	946		(a,p)
Deferred income tax charges	241			240			(b,c,d,)
Under recovered regulatory clause revenues	176			53			(e)
Asset retirement obligations	147			(33		)	(b)
Regulatory clauses	142			142			(f)
Vacation pay	71			70			(g,p)
Loss on reacquired debt	56			62			(h)
Nuclear outage	49			56			(i)
Remaining net book value of retired assets	43			54			(j)
Other regulatory assets	57			58			(k,l)
Deferred income tax credits	(2,027		)	(2,082		)	(b,d)
Other cost of removal obligations	(497		)	(609		)	(b)
Rate RSE refund	(109		)	—			(m)
Natural disaster reserve	(20		)	(38		)	(n)
Other regulatory liabilities	(45		)	(7		)	(l,o)
Total regulatory assets (liabilities), net	$	(769	)	$	(1,088	)

Note: Unless otherwise noted, the recovery and amortization periods for these regulatory assets and (liabilities) have been accepted or approved by the Alabama PSC and are as follows:

(a) Recovered and amortized over the average remaining service period which may range up to 15 years. See Note 11 for additional information.

(b) Asset retirement and removal assets and liabilities are recorded, deferred income tax assets are recovered, and deferred income tax credits are amortized over the related property lives, which may range up to 50 years. Asset retirement and other cost of removal assets and liabilities will be settled and trued up following completion of the related activities.

(c) Included in the deferred income tax charges are $10 million for 2018 and $13 million for 2017 for the retiree Medicare drug subsidy, which is being recovered and amortized through 2027.

(d) As a result of the Tax Reform Legislation, these accounts include certain deferred income tax assets and liabilities not subject to normalization. The recovery and amortization of these amounts will occur ratably over the related property lives, which may range up to 50 years. See Note 10 for additional information.

(e) Recorded and recovered or amortized over periods not exceeding 10 years. See "Rate CNP PPA," "Rate CNP Compliance," and" Rate ECR" herein for additional information.

(f) Will be amortized concurrently with the effective date of Alabama Power's next depreciation study. See "Rate RSE" herein for additional information.

(g) Recorded as earned by employees and recovered as paid, generally within one year. This includes both vacation and banked holiday pay.

(h) Recovered over the remaining life of the original issue, which may range up to 50 years.

(i) Nuclear outage costs are deferred to a regulatory asset when incurred and amortized over a subsequent 18-month period.

(j) Recorded and amortized over remaining periods up to 8 years.

(k) Comprised of components including generation site selection/evaluation costs, PPA capacity (to be recovered over the next 12 months), and other miscellaneous assets. Capitalized upon initialization of related construction projects, if applicable.

(l) Fuel-hedging assets and liabilities are recorded over the life of the underlying hedged purchase contracts, which generally do not exceed three and a half years. Upon final settlement, actual costs incurred are recovered through the energy cost recovery clause.

(m) Refund accrued as a result of the 2018 retail return exceeding the allowed range. See "Rate RSE" herein for additional information.

(n) Amortized as storm restoration and potential reliability-related expenses are incurred.

(o) Comprised of several components, primarily $33 million deferred as a result of the Alabama PSC accounting order regarding the Tax Reform Legislation. See "Tax Reform Accounting Order" herein for additional information.

(p) Not earning a return as offset in rate base by a corresponding asset or liability.

Rate RSE

The Alabama PSC has adopted Rate RSE that provides for periodic annual adjustments based upon Alabama Power's projected weighted common equity return (WCER) compared to an allowable range. Rate RSE adjustments are based on forward-looking information for the applicable upcoming calendar year. Rate RSE adjustments for any two-year period, when averaged together, cannot exceed 4.0% and any annual adjustment is limited to 5.0%. When the projected WCER is under the allowed range, there is an adjusting point of 5.98% and eligibility for a performance-based adder of seven basis points, or 0.07%, to the WCER adjusting point if Alabama Power (i) has an "A" credit rating equivalent with at least one of the recognized rating agencies or (ii) is in the top one-third of a designated customer value benchmark survey. If Alabama Power's actual retail return is above the allowed WCER range, the excess will be refunded to customers unless otherwise directed by the Alabama PSC; however, there is no provision for additional customer billings should the actual retail return fall below the WCER range. Prior to January 2019, retail rates remained unchanged when the WCER range was between 5.75% and 6.21%.

At December 31, 2016, Alabama Power's retail return exceeded the allowed WCER range which resulted in Alabama Power establishing a $73 million Rate RSE refund liability. In accordance with an Alabama PSC order issued in February 2017, Alabama Power applied the full amount of the refund to reduce the under recovered balance of Rate CNP PPA as discussed further below.

Effective in January 2017, Rate RSE increased 4.48%, or $245 million annually. At December 31, 2017, Alabama Power's actual retail return was within the allowed WCER range. Retail rates under Rate RSE were unchanged for 2018.

In conjunction with Rate RSE, Alabama Power has an established retail tariff that provides for an adjustment to customer billings to recognize the impact of a change in the statutory income tax rate. In accordance with this tariff, Alabama Power returned $267 million to retail customers through bill credits during 2018 as a result of the change in the federal income tax rate under the Tax Reform Legislation.

On May 1, 2018, the Alabama PSC approved modifications to Rate RSE and other commitments designed to position Alabama Power to address the growing pressure on its credit quality resulting from the Tax Reform Legislation, without increasing retail rates under Rate RSE in the near term. Alabama Power plans to reduce growth in total debt by increasing equity, with corresponding reductions in debt issuances, thereby de-leveraging its capital structure. Alabama Power's goal is to achieve an equity ratio of approximately 55% by the end of 2025. At December 31, 2018, Alabama Power's equity ratio was approximately 47%.

The approved modifications to Rate RSE began for billings in January 2019. The modifications include reducing the top of the allowed WCER range from 6.21% to 6.15% and modifications to the refund mechanism applicable to prior year actual results. The modifications to the refund mechanism allow Alabama Power to retain a portion of the revenue that causes the actual WCER for a given year to exceed the allowed range.

Generally, if Alabama Power's actual WCER is between 6.15% and 7.65%, customers will receive 25% of the amount between 6.15% and 6.65%, 40% of the amount between 6.65% and 7.15%, and 75% of the amount between 7.15% and 7.65%. Customers will receive all amounts in excess of an actual WCER of 7.65%.

In conjunction with these modifications to Rate RSE, on May 8, 2018, Alabama Power consented to a moratorium on any upward adjustments under Rate RSE for 2019 and 2020 and will also return $50 million to customers through bill credits in 2019.

On November 30, 2018, Alabama Power made its required annual Rate RSE submission to the Alabama PSC of projected data for calendar year 2019. Projected earnings were within the specified range; therefore, retail rates under Rate RSE remain unchanged for 2019.

At December 31, 2018, Alabama Power's retail return exceeded the allowed WCER range, which resulted in Alabama Power establishing a regulatory liability of $109 million for Rate RSE refunds. In accordance with an Alabama PSC order issued on February 5, 2019, Alabama Power will apply $75 million to reduce the Rate ECR under recovered balance and the remaining $34 million will be refunded to customers through bill credits in July through September 2019.

Rate CNP PPA

Alabama Power's retail rates, approved by the Alabama PSC, provide for adjustments under Rate CNP to recognize the placing of new generating facilities into retail service. Alabama Power may also recover retail costs associated with certificated PPAs under Rate CNP PPA. No adjustments to Rate CNP PPA occurred during the period 2016 through 2018 and no adjustment is expected in 2019. At December 31, 2018 and 2017, Alabama Power had an under recovered Rate CNP PPA balance of $25 million and $12 million, respectively, which is included in deferred under recovered regulatory clause revenues in the balance sheet.

In accordance with an accounting order issued in February 2017 by the Alabama PSC, Alabama Power eliminated the under recovered balance in Rate CNP PPA at December 31, 2016, which totaled approximately $142 million. As discussed herein under "Rate RSE," Alabama Power utilized the full amount of its $73 million Rate RSE refund liability to reduce the amount of the Rate CNP PPA under recovery and reclassified the remaining $69 million to a separate regulatory asset. The amortization of the new regulatory asset through Rate RSE will begin concurrently with the effective date of Alabama Power's next depreciation study, which is expected to occur no later than 2022. Alabama Power's current depreciation study became effective January 1, 2017.

Rate CNP Compliance

Rate CNP Compliance allows for the recovery of Alabama Power's retail costs associated with laws, regulations, and other such mandates directed at the utility industry involving the environment, security, reliability, safety, sustainability, or similar considerations impacting Alabama Power's facilities or operations. Rate CNP Compliance is based on forward-looking information and provides for the recovery of these costs pursuant to a factor that is calculated annually. Compliance costs to be recovered include operations and maintenance expenses, depreciation, and a return on certain invested capital. Revenues for Rate CNP Compliance, as recorded on the financial statements, are adjusted for differences in actual recoverable costs and amounts billed in current regulated rates. Accordingly, changes in the billing factor will have no significant effect on Southern Company's or Alabama Power's revenues or net income, but will affect annual cash flow. Changes in Rate CNP Compliance-related operations and maintenance expenses and depreciation generally will have no effect on Southern Company's or Alabama Power's net income.

In accordance with an accounting order issued in February 2017 by the Alabama PSC, Alabama Power reclassified $36 million of its under recovered balance in Rate CNP Compliance to a separate regulatory asset. The amortization of the new regulatory asset through Rate RSE will begin concurrently with the effective date of Alabama Power's next depreciation study, which is expected to occur no later than 2022. Alabama Power's current depreciation study became effective January 1, 2017.

In December 2017, the Alabama PSC issued a consent order that Alabama Power leave in effect for 2018 the factors associated with Alabama Power's compliance costs for the year 2017, with any under-collected amount for prior years deemed recovered before any current year amounts.

On November 30, 2018, Alabama Power submitted calculations associated with its cost of complying with environmental mandates, as provided under Rate CNP Compliance. The filing reflected a projected unrecovered retail revenue requirement for environmental compliance of approximately $205 million, which is being recovered in the billing months of January 2019 through December 2019.

At December 31, 2018, Alabama Power had an under recovered Rate CNP Compliance balance of $42 million, which is included in customer accounts receivable, and $17 million at December 31, 2017 included in deferred under recovered regulatory clause revenues in the balance sheet.

Rate ECR

Alabama Power has established energy cost recovery rates under Alabama Power's Rate ECR as approved by the Alabama PSC. Rates are based on an estimate of future energy costs and the current over or under recovered balance. Revenues recognized under Rate ECR and recorded on the financial statements are adjusted for the difference in actual recoverable fuel costs and amounts billed in current regulated rates. The difference in the recoverable fuel costs and amounts billed give rise to the over or under recovered amounts recorded as regulatory assets or liabilities. Alabama Power, along with the Alabama PSC, continually monitors the over or under recovered cost balance to determine whether an adjustment to billing rates is required. Changes in the Rate ECR factor have no significant effect on Southern Company's or Alabama Power's net income, but will impact operating cash flows.

In accordance with an accounting order issued in February 2017 by the Alabama PSC, Alabama Power reclassified $36 million of its under recovered balance in Rate ECR to a separate regulatory asset. The amortization of the new regulatory asset through Rate RSE will begin concurrently with the effective date of Alabama Power's next depreciation study, which is expected to occur no later than 2022. Alabama Power's current depreciation study became effective January 1, 2017.

In December 2017, the Alabama PSC issued a consent order that Alabama Power leave in effect for 2018 the energy cost recovery rates which began in 2017.

On May 1, 2018, the Alabama PSC approved an increase to Rate ECR from 2.015 cents per KWH to 2.353 cents per KWH effective July 2018 through December 2018. On December 4, 2018, the Alabama PSC issued a consent order to leave this rate in effect through December 31, 2019. This change is expected to increase collections by approximately $183 million in 2019. Absent any further order from the Alabama PSC, in January 2020, the rates will return to the originally authorized 5.910 cents per KWH.

As discussed herein under "Rate RSE," in accordance with an Alabama PSC order issued on February 5, 2019, Alabama Power will utilize $75 million of the 2018 Rate RSE refund liability to reduce the Rate ECR under recovered balance.

At December 31, 2018, Alabama Power's under recovered fuel costs totaled $109 million, of which $18 million is included in customer accounts receivable and $91 million is included in deferred under recovered regulatory clause revenues on Southern Company's and Alabama Power's balance sheets. At December 31, 2017, Alabama Power had an under recovered fuel balance of $25 million, which was included in deferred under recovered regulatory clause revenues on Southern Company's and Alabama Power's balance sheets. These classifications are based on estimates, which include such factors as weather, generation availability, energy demand, and the price of energy. A change in any of these factors could have a material impact on the timing of any recovery or return of fuel costs.

Tax Reform Accounting Order

On May 1, 2018, the Alabama PSC approved an accounting order that authorized Alabama Power to defer the benefits of federal excess deferred income taxes associated with the Tax Reform Legislation for the year ended December 31, 2018 as a regulatory liability and to use up to $30 million of such deferrals to offset under recovered amounts under Rate ECR. The estimated deferrals for the year ended December 31, 2018 totaled approximately $63 million, subject to adjustment following the filing of the 2018 tax return, of which $30 million was used to offset the Rate ECR under recovered balance and $33 million is recorded in other regulatory liabilities, deferred on the balance sheet to be used for the benefit of customers as determined by the Alabama PSC at a future date. See Note 10 under "Current and Deferred Income Taxes" for additional information.

Software Accounting Order

On February 5, 2019, the Alabama PSC approved an accounting order that authorizes Alabama Power to establish a regulatory asset for operations and maintenance costs associated with software implementation projects. The regulatory asset will be amortized ratably over the life of the related software.

Rate NDR

Based on an order from the Alabama PSC, Alabama Power maintains a reserve for operations and maintenance expenses to cover the cost of damages from major storms to its transmission and distribution facilities. The order approves a separate monthly Rate NDR charge to customers consisting of two components. The first component is intended to establish and maintain a reserve balance for future storms and is an on-going part of customer billing. When the reserve balance falls below $50 million, a reserve establishment charge will be activated (and the on-going reserve maintenance charge concurrently suspended) until the reserve balance reaches $75 million. In December 2017, the reserve maintenance charge was suspended and the reserve establishment charge was activated as a result of the NDR balance falling below $50 million. Alabama Power expects to collect approximately $16 million annually until the reserve balance is restored to $75 million. The NDR balance at December 31, 2018 was $20 million and is included in other regulatory liabilities, deferred on the balance sheet.

The second component of the Rate NDR charge is intended to allow recovery of any existing deferred storm-related operations and maintenance costs and any future reserve deficits over a 24-month period. The Alabama PSC order gives Alabama Power authority to record a deficit balance in the NDR when costs of storm damage exceed any established reserve balance. Absent further Alabama PSC approval, the maximum total Rate NDR charge consisting of both components is $10 per month per non-residential customer account and $5 per month per residential customer account. Alabama Power has the authority, based on an order from the Alabama PSC, to accrue certain additional amounts as circumstances warrant. The order allows for reliability-related expenditures to be charged against the additional accruals when the NDR balance exceeds $75 million. Alabama Power may designate a portion of the NDR to reliability-related expenditures as a part of an annual budget process for the following year or during the current year for identified unbudgeted reliability-related expenditures that are incurred. Accruals that have not been designated can be used to offset storm charges. Additional accruals to the NDR will enhance Alabama Power's ability to deal with the financial effects of future natural disasters, promote system reliability, and offset costs retail customers would otherwise bear. No such accruals were recorded or designated in any period presented.

As revenue from the Rate NDR charge is recognized, an equal amount of operations and maintenance expenses related to the NDR will also be recognized. As a result, the Rate NDR charge will not have an effect on net income but will impact operating cash flows.

Environmental Accounting Order

Based on an order from the Alabama PSC (Environmental Accounting Order), Alabama Power is allowed to establish a regulatory asset to record the unrecovered investment costs, including the unrecovered plant asset balance and the unrecovered costs associated with site removal and closure associated with future unit retirements caused by environmental regulations. The regulatory asset is being amortized and recovered over the affected unit's remaining useful life, as established prior to the decision regarding early retirement through Rate CNP Compliance. At December 31, 2018, this regulatory asset had a balance of $42 million, of which $10 million is included in other regulatory assets, current and $32 million is included in other regulatory assets, deferred on the balance sheet.

Subsequent to December 31, 2018, Alabama Power determined that Plant Gorgas Units 8, 9, and 10 (approximately 1,000 MWs) will be retired by April 15, 2019 due to the expected costs of compliance with federal and state environmental regulations. In accordance with the Environmental Accounting Order, approximately $740 million of net investment costs will be transferred to a regulatory asset at the retirement date and recovered over the affected units' remaining useful lives, as established prior to the decision to retire.

Georgia Power

Regulatory Assets and Liabilities

Regulatory assets and (liabilities) reflected in the balance sheets of Georgia Power at December 31, 2018 and 2017 relate to:

	2018			2017			Note
	(in millions)
Retiree benefit plans	$	1,295		$	1,313		(a, l)
Asset retirement obligations	2,644			945			(b, l)
Deferred income tax charges	522			521			(b, c, l)
Storm damage reserves	416			333			(d)
Remaining net book value of retired assets	127			146			(e)
Loss on reacquired debt	277			127			(f, l)
Vacation pay	91			91			(g, l)
Other cost of removal obligations	68			40			(b)
Environmental remediation	55			49			(h)
Other regulatory assets	135			106			(i)
Deferred income tax credits	(3,080		)	(3,248		)	(b, c)
Customer refunds	(165		)	(188		)	(j)
Other regulatory liabilities	(7		)	(3		)	(k, l)
Total regulatory assets (liabilities), net	$	2,378		$	232

Note: Unless otherwise noted, the recovery and amortization periods for these regulatory assets and (liabilities) are approved by the Georgia PSC and are as follows:

(a) Recovered and amortized over the average remaining service period which may range up to 14 years. See Note 11 for additional information.

(b) Through 2019, Georgia Power is recovering approximately $60 million annually for AROs, which is expected to be adjusted in the Georgia Power 2019 Base Rate Case. Asset retirement and removal liabilities will be settled and trued up following completion of the related activities. See Note 6 for additional information on AROs. Other cost of removal obligations and deferred income tax assets are recovered and deferred income tax liabilities are amortized over the related property lives, which may range up to 65 years. Included in the deferred income tax assets is $17 million for the retiree Medicare drug subsidy, which is being recovered and amortized through 2022.

(c) As a result of the Tax Reform Legislation, these balances include $145 million of deferred income tax assets related to CWIP for Plant Vogtle Units 3 and 4 and approximately $610 million of deferred income tax liabilities, neither of which are subject to normalization. The recovery and amortization of these amounts is expected to be determined in the Georgia Power 2019 Base Rate Case. See "Rate Plans" herein and Note 10 for additional information.

(d) Through 2019, Georgia Power is recovering approximately $30 million annually for storm damage, which is expected to be adjusted in the Georgia Power 2019 Base Rate Case. See "Storm Damage Recovery" herein and Note 1 under "Storm Damage Reserves" for additional information.

(e) The net book value of Plant Branch Units 1 through 4 at December 31, 2018 was $87 million, which is being amortized over the units' remaining useful lives through 2024. The net book value of Plant Mitchell Unit 3 at December 31, 2018 was $9 million, which will continue to be amortized through December 31, 2019 as provided in the 2013 ARP. Amortization of the remaining approximately $4 million net book value of Plant Mitchell Unit 3 at December 31, 2019 and a total of approximately $31 million related to obsolete inventories of certain retired units is expected to be determined in the Georgia Power 2019 Base Rate Case. See "Integrated Resource Plan" herein 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, which currently does not exceed 34 years.

(g) Recorded as earned by employees and recovered as paid, generally within one year. This includes both vacation and banked holiday pay.

(h) Through 2019, Georgia Power is recovering approximately $2 million annually for environmental remediation, which is expected to be adjusted in the Georgia Power 2019 Base Rate Case. See Note 3 under Environmental Remediation for additional information.

(i) Comprised of several components including future generation costs, deferred nuclear outage costs, cancelled construction projects, building lease, and fuel-hedging losses. The timing of recovery of approximately $50 million for a future generation site is expected to be determined in the Georgia Power 2019 Base Rate Case. Nuclear outage costs are recorded and recovered or amortized over the outage cycles of each nuclear unit, which do not exceed 24 months. Approximately $30 million of costs associated with construction of environmental controls that will not be completed as a result of unit retirements are being amortized through 2022. The building lease is recorded and recovered or amortized through 2020. Fuel-hedging losses are recovered through Georgia Power's fuel cost recovery mechanism upon final settlement. See "Integrated Resource Plan" herein for additional information on future generation costs.

(j) At December 31, 2018, approximately $55 million was accrued and outstanding for refund pursuant to the Georgia Power Tax Reform Settlement Agreement and approximately $100 million was accrued for refund, subject to review and approval by the Georgia PSC, as a result of the 2018 retail ROE exceeding the allowed retail ROE range. See "Rate Plans" herein for additional information.

(k) Comprised of Demand-Side Management (DSM) tariff over recovery and fuel-hedging gains. The amortization of DSM tariff over recovery of $3 million at December 31, 2018 is expected to be determined in the Georgia Power 2019 Base Rate Case. Fuel-hedging gains are refunded through Georgia Power's fuel cost recovery mechanism upon final settlement. See "Rate Plans" herein for additional information on customer refunds and DSM tariffs.

(l) Generally not earning a return as they are excluded from rate base or are offset in rate base by a corresponding asset or liability.

Rate Plans

Pursuant to the terms and conditions of a settlement agreement related to Southern Company's acquisition of Southern Company Gas approved by the Georgia PSC in 2016, the 2013 ARP will continue in effect until December 31, 2019, and Georgia Power will be required to file its next base rate case by July 1, 2019. Furthermore, through December 31, 2019, Georgia Power will retain its merger savings, net of transition costs, as defined in the settlement agreement; through December 31, 2022, such net merger savings will be shared on a 60/40 basis with customers; thereafter, all merger savings will be retained by customers.

There were no changes to Georgia Power's traditional base tariff rates, Environmental Compliance Cost Recovery (ECCR) tariff, DSM tariffs, or Municipal Franchise Fee tariff in 2017 or 2018.

Under the 2013 ARP, Georgia Power's retail ROE is set at 10.95% and earnings are evaluated against a retail ROE range of 10.00% to 12.00%. Two-thirds of any earnings above 12.00% will be directly refunded to customers, with the remaining one-third retained by Georgia Power. There will be no recovery of any earnings shortfall below 10.00% on an actual basis. In 2016, Georgia Power's retail ROE exceeded 12.00%, and Georgia Power refunded to retail customers in 2018 approximately $40 million as approved by the Georgia PSC. On February 5, 2019, the Georgia PSC approved a settlement between Georgia Power and the staff of the Georgia PSC under which Georgia Power's retail ROE for 2017 was stipulated to exceed 12.00% and Georgia Power will reduce certain regulatory assets by approximately $4 million in lieu of providing refunds to retail customers. In 2018, Georgia Power's retail ROE exceeded 12.00%, and Georgia Power accrued approximately $100 million to refund to retail customers, subject to review and approval by the Georgia PSC.

On April 3, 2018, the Georgia PSC approved the Georgia Power Tax Reform Settlement Agreement. Pursuant to the Georgia Power Tax Reform Settlement Agreement, to reflect the federal income tax rate reduction impact of the Tax Reform Legislation, Georgia Power will refund to customers a total of $330 million through bill credits. Georgia Power issued bill credits of approximately $130 million in 2018 and will issue bill credits of approximately $95 million in June 2019 and $105 million in February 2020. In addition, Georgia Power is deferring as a regulatory liability (i) the revenue equivalent of the tax expense reduction resulting from legislation lowering the Georgia state income tax rate from 6.00% to 5.75% in 2019 and (ii) the entire benefit of federal and state excess accumulated deferred income taxes, which is expected to total approximately $700 million at December 31, 2019. At December 31, 2018, the related regulatory liability balance totaled $610 million. The amortization of these regulatory liabilities is expected to be addressed in the Georgia Power 2019 Base Rate Case. If there is not a base rate case in 2019, customers will receive $185 million in annual bill credits beginning in 2020, with any additional federal and state income tax savings deferred as a regulatory liability, until Georgia Power's next base rate case.

To address some of the negative cash flow and credit quality impacts of the Tax Reform Legislation, the Georgia PSC also approved an increase in Georgia Power's retail equity ratio to the lower of (i) Georgia Power's actual common equity weight in its capital structure or (ii) 55%, until the Georgia Power 2019 Base Rate Case. At December 31, 2018, Georgia Power's actual retail common equity ratio (on a 13-month average basis) was approximately 55%. Benefits from reduced federal income tax rates in excess of the amounts refunded to customers will be retained by Georgia Power to cover the carrying costs of the incremental equity in 2018 and 2019.

Integrated Resource Plan

In 2016, the Georgia PSC approved Georgia Power's triennial Integrated Resource Plan (2016 IRP) including the reclassification of the remaining net book value of Plant Mitchell Unit 3 and costs associated with materials and supplies remaining at the unit retirement date to a regulatory asset. Recovery of the unit's net book value will continue through December 31, 2019, as provided in the 2013 ARP. The timing of the recovery of the remaining balance of the unit's net book value as of December 31, 2019 and costs associated with materials and supplies remaining at the unit retirement date was deferred for consideration in the Georgia Power 2019 Base Rate Case.

In the 2016 IRP, the Georgia PSC also approved recovery of costs up to $99 million through June 30, 2019 to preserve nuclear generation as an option at a future generation site in Stewart County, Georgia. In March 2017, the Georgia PSC approved Georgia Power's decision to suspend work at the site due to changing economics, including lower load forecasts and fuel costs. The timing of recovery for costs incurred of approximately $50 millionis expected to be determined by the Georgia PSC in the Georgia Power 2019 Base Rate Case.

On January 31, 2019, Georgia Power filed its triennial IRP (2019 IRP). The filing includes a request to decertify and retire Plant Hammond Units 1 through 4 (840 MWs) and Plant McIntosh Unit 1 (142.5 MWs) upon approval of the 2019 IRP.

In the 2019 IRP, Georgia Power requested approval to reclassify the remaining net book value of Plant Hammond Units 1 through 4 (approximately $520 million at December 31, 2018) upon retirement to a regulatory asset to be amortized ratably over a period equal to the applicable unit's remaining useful life through 2035. For Plant McIntosh Unit 1, Georgia Power requested approval to reclassify the remaining net book value (approximately $40 million at December 31, 2018) upon retirement to a regulatory asset to be amortized over a three-year period to be determined in the Georgia Power 2019 Base Rate Case. Georgia Power also requested approval to reclassify any unusable material and supplies inventory balances remaining at the applicable unit's retirement date to a regulatory asset for recovery over a period to be determined in the Georgia Power 2019 Base Rate Case.

The 2019 IRP also includes a request to certify approximately 25 MWs of capacity at Plant Scherer Unit 3 for the retail jurisdiction beginning January 1, 2020, following the expiration of a wholesale PPA.

The 2019 IRP also includes details regarding ARO costs associated with ash pond and landfill closures and post-closure care. Georgia Power requested the timing and rate of recovery of these costs be determined by the Georgia PSC in the Georgia Power 2019 Base Rate Case. See Note 6 for additional information regarding Georgia Power's AROs.

Georgia Power also requested approval to issue two capacity-based requests for proposals (RFP). If approved, the first capacity-based RFP will seek resources that can provide capacity beginning in 2022 or 2023 and the second capacity-based RFP will seek resources that can provide capacity beginning in 2026, 2027, or 2028. Additionally, the 2019 IRP includes a request to procure an additional 1,000 MWs of renewable resources through a competitive bidding process. Georgia Power also proposed to invest in a portfolio of up to 50 MWs of battery energy storage technologies.

A decision from the Georgia PSC on the 2019 IRP is expected in mid-2019.

The ultimate outcome of these matters cannot be determined at this time.

Fuel Cost Recovery

Georgia Power has established fuel cost recovery rates approved by the Georgia PSC. In 2016, the Georgia PSC approved Georgia Power's request to lower annual billings under an interim fuel rider by approximately $313 million effective June 1, 2016, which expired on December 31, 2017. On August 16, 2018, the Georgia PSC approved the deferral of Georgia Power's next fuel case to no later than March 16, 2020, with new rates, if any, to be effective June 1, 2020. Georgia Power continues to be allowed to adjust its fuel cost recovery rates under an interim fuel rider prior to the next fuel case if the under or over recovered fuel balance exceeds $200 million. Georgia Power's under recovered fuel balance totaled $115 million and $165 million at December 31, 2018 and 2017, respectively, and is included in under recovered fuel clause revenues on Southern Company's and Georgia Power's balance sheets.

Georgia Power's fuel cost recovery mechanism includes costs associated with a natural gas hedging program, as revised and approved by the Georgia PSC, allowing the use of an array of derivative instruments within a 48-month time horizon.

Fuel cost recovery revenues as recorded on the financial statements are adjusted for differences in actual recoverable fuel costs and amounts billed in current regulated rates. Accordingly, changes in the billing factor will not have a significant effect on Southern Company's or Georgia Power's revenues or net income, but will affect operating cash flows.

Storm Damage Recovery

Georgia Power defers and recovers certain costs related to damages from major storms as mandated by the Georgia PSC. Beginning January 1, 2014, Georgia Power is accruing $30 million annually under the 2013 ARP that is recoverable through base rates. At December 31, 2018 and 2017, the balance in the regulatory asset related to storm damage was $416 million and $333 million, respectively, with $30 million included in other regulatory assets, current for each year and $386 million and $303 million included in other regulatory assets, deferred, respectively. During October 2018, Hurricane Michael caused significant damage to Georgia Power's transmission and distribution facilities. The incremental restoration costs related to this hurricane deferred in the regulatory asset for storm damage totaled approximately $115 million. Hurricanes Irma and Matthew also caused significant damage to Georgia Power's transmission and distribution facilities during September 2017 and October 2016, respectively. The incremental restoration costs related to Hurricanes Irma and Matthew deferred in the regulatory asset for storm damage totaled approximately $250 million. The rate of storm damage cost recovery is expected to be adjusted as part of the Georgia Power 2019 Base Rate Case and further adjusted in future regulatory proceedings as necessary. The ultimate outcome of this matter cannot be determined at this time.

Nuclear Construction

In 2009, the Georgia PSC certified construction of Plant Vogtle Units 3 and 4. Georgia Power holds a 45.7% ownership interest in Plant Vogtle Units 3 and 4. In 2012, the NRC issued the related combined construction and operating licenses, which allowed full construction of the two AP1000 nuclear units (with electric generating capacity of approximately 1,100 MWs each) and related facilities to begin. Until March 2017, construction on Plant Vogtle Units 3 and 4 continued under the Vogtle 3 and 4 Agreement, which was a substantially fixed price agreement. In March 2017, the EPC Contractor filed for bankruptcy protection under Chapter 11 of the U.S. Bankruptcy Code.

In connection with the EPC Contractor's bankruptcy filing, Georgia Power, acting for itself and as agent for the Vogtle Owners, entered into the Interim Assessment Agreement with the EPC Contractor to allow construction to continue. The Interim Assessment Agreement expired in July 2017 when Georgia Power, acting for itself and as agent for the other Vogtle Owners, and the EPC Contractor entered into the Vogtle Services Agreement. Under the Vogtle Services Agreement, Westinghouse provides facility design and engineering services, procurement and technical support, and staff augmentation on a time and materials cost basis. The Vogtle Services Agreement provides that it will continue until the start-up and testing of Plant Vogtle Units 3 and 4 are complete and electricity is generated and sold from both units. The Vogtle Services Agreement is terminable by the Vogtle Owners upon 30 days' written notice.

In October 2017, Georgia Power, acting for itself and as agent for the other Vogtle Owners, executed the Bechtel Agreement, a cost reimbursable plus fee arrangement, whereby Bechtel is reimbursed for actual costs plus a base fee and an at-risk fee, which is subject to adjustment based on Bechtel's performance against cost and schedule targets. Each Vogtle Owner is severally (not jointly) liable for its proportionate share, based on its ownership interest, of all amounts owed to Bechtel under the Bechtel Agreement. The Vogtle Owners may terminate the Bechtel Agreement at any time for their convenience, provided that the Vogtle Owners will be required to pay amounts related to work performed prior to the termination (including the applicable portion of the base fee), certain termination-related costs, and, at certain stages of the work, the applicable portion of the at-risk fee. Bechtel may terminate the Bechtel Agreement under certain circumstances, including certain Vogtle Owner suspensions of work, certain breaches of the Bechtel Agreement by the Vogtle Owners, Vogtle Owner insolvency, and certain other events. Pursuant to the Loan Guarantee Agreement between Georgia Power and the DOE, Georgia Power is required to obtain the DOE's approval of the Bechtel Agreement prior to obtaining any further advances under the Loan Guarantee Agreement.

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)	$	8.0
Construction contingency estimate	0.4
Total project capital cost forecast(a)(b)	8.4
Net investment as of December 31, 2018(b)	(4.6		)
Remaining estimate to complete(a)	$	3.8

(a) Excludes financing costs expected to be capitalized through AFUDC of approximately $315 million.

(b) Net of $1.7 billion received from Toshiba under the Guarantee Settlement Agreement and approximately $188 million in related Customer Refunds.

Georgia Power estimates that its financing costs for construction of Plant Vogtle Units 3 and 4 will total approximately $3.1 billion, of which $1.9 billion had been incurred through December 31, 2018.

As construction continues, challenges with management of contractors, subcontractors, and vendors; labor productivity, availability, and/or cost escalation; procurement, fabrication, delivery, assembly, and/or installation and testing, including any required engineering changes, of plant systems, structures, and components (some of which are based on new technology that only recently began initial operation in the global nuclear industry at this scale); or other issues could arise and change the projected schedule and estimated cost. Monthly construction production targets required to maintain the current project schedule will continue to increase significantly throughout 2019. To meet these increasing monthly targets, existing craft construction productivity must improve and additional craft laborers must be retained and deployed.

Georgia Power and Southern Nuclear believe it is a leading practice in connection with a construction project of this size and complexity to periodically validate recent construction progress in comparison to the projected schedule and to verify and update quantities of commodities remaining to install, labor productivity, and forecasted staffing needs. This verification process, led by Southern Nuclear, was underway as of December 31, 2018 and is expected to be completed during the second quarter 2019. Georgia Power currently does not anticipate any material changes to the total estimated project capital cost forecast for Plant Vogtle Units 3 and 4 or the expected in-service dates of November 2021 and November 2022, respectively, resulting from this verification process. However, the ultimate impact on cost and schedule, if any, will not be known until the verification process is completed. Georgia Power is required to report the results and any project impacts to the Georgia PSC by May 15, 2019.

There have been technical and procedural challenges to the construction and licensing of Plant Vogtle Units 3 and 4 at the federal and state level and additional challenges may arise. Processes are in place that are designed to assure compliance with the requirements specified in the Westinghouse Design Control Document and the combined construction and operating licenses, including inspections by Southern Nuclear and the NRC that occur throughout construction. As a result of such compliance processes, certain license amendment requests have been filed and approved or are pending before the NRC. Various design and other licensing-based compliance matters, including the timely resolution of ITAAC and the related approvals by the NRC, may arise, which may result in additional license amendments or require other resolution. If any license amendment requests or other licensing-based compliance issues are not resolved in a timely manner, there may be delays in the project schedule that could result in increased costs.

The ultimate outcome of these matters cannot be determined at this time. However, any extension of the project schedule is currently estimated to result in additional base capital costs of approximately $50 million per month, based on Georgia Power's ownership interests, and AFUDC of approximately $12 million per month. While Georgia Power is not precluded from seeking recovery of any future capital cost forecast increase, management will ultimately determine whether or not to seek recovery. Any further changes to the capital cost forecast that are not expected to be recoverable through regulated rates will be required to be charged to income and such charges could be material.

Joint Owner Contracts

In November 2017, the Vogtle Owners entered into an amendment to their joint ownership agreements for Plant Vogtle Units 3 and 4 to provide for, among other conditions, additional Vogtle Owner approval requirements. Effective August 31, 2018, the Vogtle Owners further amended the joint ownership agreements to clarify and provide procedures for certain provisions of the joint ownership agreements related to adverse events that require the vote of the holders of at least 90% of the ownership interests in Plant Vogtle Units 3 and 4 to continue construction (as amended, and together with the November 2017 amendment, the Vogtle Joint Ownership Agreements). The Vogtle Joint Ownership Agreements also confirm that the Vogtle Owners' sole recourse against Georgia Power or Southern Nuclear for any action or inaction in connection with their performance as agent for the Vogtle Owners is limited to removal of Georgia Power and/or Southern Nuclear as agent, except in cases of willful misconduct.

As a result of the increase in the total project capital cost forecast and Georgia Power's decision not to seek rate recovery of the increase in the base capital costs as described below, the holders of at least 90% of the ownership interests in Plant Vogtle Units 3 and 4 were required to vote to continue construction. On September 26, 2018, the Vogtle Owners unanimously voted to continue construction of Plant Vogtle Units 3 and 4.

Amendments to the Vogtle Joint Ownership Agreements

In connection with the vote to continue construction, Georgia Power entered into (i) a binding term sheet (Vogtle Owner Term Sheet) with the other Vogtle Owners and MEAG's wholly-owned subsidiaries MEAG Power SPVJ, LLC (MEAG SPVJ), MEAG Power SPVM, LLC (MEAG SPVM), and MEAG Power SPVP, LLC (MEAG SPVP) to take certain actions which partially mitigate potential financial exposure for the other Vogtle Owners, including additional amendments to the Vogtle Joint Ownership Agreements and the purchase of PTCs from the other Vogtle Owners, and (ii) a term sheet (MEAG Term Sheet) with MEAG and MEAG SPVJ to provide funding with respect to MEAG SPVJ's ownership interest in Plant Vogtle Units 3 and 4 (Project J) under certain circumstances. On January 14, 2019, Georgia Power, MEAG, and MEAG SPVJ entered into an agreement to implement the provisions of the MEAG Term Sheet (MEAG Funding Agreement). On February 18, 2019, Georgia Power, the other Vogtle Owners, and MEAG's wholly-owned subsidiaries MEAG SPVJ, MEAG SPVM, and MEAG SPVP entered into certain amendments to the Vogtle Joint Ownership Agreements to implement the provisions of the Vogtle Owner Term Sheet (Global Amendments).

Pursuant to the Global Amendments, and consistent with the Vogtle Owner Term Sheet, the Vogtle Joint Ownership Agreements were modified as follows: (i) each Vogtle Owner must pay its proportionate share of qualifying construction costs for Plant Vogtle Units 3 and 4 based on its ownership percentage up to the estimated cost at completion (EAC) for Plant Vogtle Units 3 and 4 which formed the basis of Georgia Power's forecast of $8.4 billion in the nineteenth VCM plus $800 million; (ii) Georgia Power will be responsible for 55.7% of actual qualifying construction costs between $800 million and $1.6 billion over the EAC in the nineteenth VCM (resulting in $80 million of potential additional costs to Georgia Power), with the remaining Vogtle Owners responsible for 44.3% of such costs pro rata in accordance with their respective ownership interests; and (iii) Georgia Power will be responsible for 65.7% of qualifying construction costs between $1.6 billion and $2.1 billion over the EAC in the nineteenth VCM (resulting in a further $100 million of potential additional costs to Georgia Power), with the remaining Vogtle Owners responsible for 34.3% of such costs pro rata in accordance with their respective ownership interests.

If the EAC is revised and exceeds the EAC in the nineteenth VCM by more than $2.1 billion, each of the other Vogtle Owners will have a one-time option at the time the project budget forecast is so revised to tender a portion of its ownership interest to Georgia Power in exchange for Georgia Power's agreement to pay 100% of such Vogtle Owner's remaining share of total construction costs in excess of the EAC in the nineteenth VCM plus $2.1 billion. In this event, Georgia Power will have the option of cancelling the project in lieu of purchasing a portion of the ownership interest of any other Vogtle Owner. If Georgia Power accepts the offer to purchase a portion of another Vogtle Owner's ownership interest in Plant Vogtle Units 3 and 4, the ownership interest(s) to be conveyed from the tendering Vogtle Owner(s) to Georgia Power will be calculated based on the proportion of the cumulative amount of construction costs paid by each such tendering Vogtle Owner(s) and by Georgia Power as of the COD of Plant Vogtle Unit 4. For purposes of this calculation, payments made by Georgia Power on behalf of another Vogtle Owner in accordance with the second and third items described in the paragraph above will be treated as payments made by the applicable Vogtle Owner.

In the event the actual costs of construction at completion of a Unit are less than the EAC reflected in the nineteenth VCM report and such Unit is placed in service in accordance with the schedule projected in the nineteenth VCM report (i.e., Plant Vogtle Unit 3 is placed in service by November 2021 or Plant Vogtle Unit 4 is placed in service by November 2022), Georgia Power will be entitled to 60.7% of the cost savings with respect to the relevant Unit and the remaining Vogtle Owners will be entitled to 39.3% of such savings on a pro rata basis in accordance with their respective ownership interests.

For purposes of the foregoing provisions, qualifying construction costs will not include costs (i) resulting from force majeure events, including governmental actions or inactions (or significant delays associated with issuance of such actions) that affect the licensing, completion, start-up, operations, or financing of Plant Vogtle Units 3 and 4, administrative proceedings or litigation regarding ITAAC or other regulatory challenges to commencement of operation of Plant Vogtle Units 3 and 4, and changes in laws or regulations governing Plant Vogtle Units 3 and 4, (ii) legal fees and legal expenses incurred due to litigation with contractors or subcontractors that are not subsidiaries or affiliates of Southern Company, and (iii) additional costs caused by requests from the Vogtle Owners other than Georgia Power, except for the exercise of a right to vote granted under the Vogtle Joint Ownership Agreements, that increase costs by $100,000 or more.

Pursuant to the Global Amendments, and consistent with the Vogtle Owner Term Sheet, the provisions of the Vogtle Joint Ownership Agreements requiring that Vogtle Owners holding 90% of the ownership interests in Plant Vogtle Units 3 and 4 vote to continue construction following certain adverse events (Project Adverse Events) were modified. Pursuant to the Global Amendments, the holders of at least 90% of the ownership interests in Plant Vogtle Units 3 and 4 must vote to continue construction if certain Project Adverse Events occur, including: (i) the bankruptcy of Toshiba; (ii) the termination or rejection in bankruptcy of certain agreements, including the Vogtle Services Agreement, the Bechtel Agreement, or the agency agreement with Southern Nuclear; (iii) Georgia Power publicly announces its intention not to submit for rate recovery any portion of its investment in Plant Vogtle Units 3 and 4 or the Georgia PSC determines that any of Georgia Power's costs relating to the construction of Plant Vogtle Units 3 and 4 will not be recovered in retail rates, excluding any additional amounts paid by Georgia Power on behalf of the other Vogtle Owners pursuant to the Global Amendments described above and the first 6% of costs during any six-month VCM reporting period that are disallowed by the Georgia PSC for recovery, or for which Georgia Power elects not to seek cost recovery, through retail rates; and (iv) an incremental extension of one year or more over the most recently approved schedule. Under the Global Amendments, Georgia Power may cancel the project at any time in its sole discretion.

In addition, pursuant to the Vogtle Joint Ownership Agreements, the required approval of holders of ownership interests in Plant Vogtle Units 3 and 4 is at least (i) 90% for a change of the primary construction contractor and (ii) 67% for material amendments to the Vogtle Services Agreement or agreements with Southern Nuclear or the primary construction contractor, including the Bechtel Agreement.

The Global Amendments provide that if the holders of at least 90% of the ownership interests fail to vote in favor of continuing the project following any future Project Adverse Event, work on Plant Vogtle Units 3 and 4 will continue for a period of 30 days if the holders of more than 50% of the ownership interests vote in favor of continuing construction (Majority Voting Owners). In such a case, the Vogtle Owners (i) have agreed to negotiate in good faith towards the resumption of the project, (ii) if no agreement is reached during such 30-day period, the project will be cancelled, and (iii) in the event of such a cancellation, the Majority Voting Owners will be obligated to reimburse any other Vogtle Owner for the incremental costs it incurred during such 30-day negotiation period.

Purchase of PTCs During Commercial Operation

Pursuant to the Global Amendments, and consistent with the Vogtle Owner Term Sheet, Georgia Power has agreed to purchase additional PTCs from OPC, Dalton, MEAG SPVM, MEAG SPVP, and MEAG SPVJ (to the extent any MEAG SPVJ PTC rights remain after any purchases required under the MEAG Funding Agreement as described below) at varying purchase prices dependent upon the actual cost to complete construction of Plant Vogtle Units 3 and 4 as compared to the EAC reflected in the nineteenth VCM report. The purchases are at the option of the applicable Vogtle Owner.

Potential Funding to MEAG Project J

Pursuant to the MEAG Funding Agreement, and consistent with the MEAG Term Sheet, if MEAG SPVJ is unable to make its payments due under the Vogtle Joint Ownership Agreements solely as a result of the occurrence of one of the following situations that materially impedes access to capital markets for MEAG for Project J: (i) the conduct of JEA or the City of Jacksonville, such as JEA's legal challenges of its obligations under a PPA with MEAG (PPA-J), or (ii) PPA-J is declared void by a court of competent jurisdiction or rejected by JEA under the applicable provisions of the U.S. Bankruptcy Code (each of (i) and (ii), a JEA Default), at MEAG's request, Georgia Power will purchase from MEAG SPVJ the rights to PTCs attributable to MEAG SPVJ's share of Plant Vogtle Units 3 and 4 (approximately 206 MWs) within 30 days of such request at varying prices dependent upon the stage of construction of Plant Vogtle Units 3 and 4. The aggregate purchase price of the PTCs, together with any advances made as described in the next paragraph, shall not exceed $300 million.

At the option of MEAG, as an alternative or supplement to Georgia Power's purchase of PTCs as described above, Georgia Power has agreed to provide up to $250 million in funding to MEAG for Project J in the form of advances (either advances under the Vogtle Joint Ownership Agreements or the purchase of MEAG Project J bonds, at the discretion of Georgia Power), subject to any required approvals of the Georgia PSC and the DOE.

In the event MEAG SPVJ certifies to Georgia Power that it is unable to fund its obligations under the Vogtle Joint Ownership Agreements as a result of a JEA Default and Georgia Power becomes obligated to provide funding as described above, MEAG is required to (i) assign to Georgia Power its right to vote on any future Project Adverse Event and (ii) diligently pursue JEA for its breach of PPA-J. In addition, Georgia Power agreed that it will not sue MEAG for any amounts due from MEAG SPVJ under MEAG's guarantee of MEAG SPVJ's obligations so long as MEAG SPVJ complies with the terms of the MEAG Funding Agreement as to its payment obligations and the other non-payment provisions of the Vogtle Joint Ownership Agreements.

Under the terms of the MEAG Funding Agreement, Georgia Power may cancel the project in lieu of providing funding in the form of advances or PTC purchases.

The ultimate outcome of these matters cannot be determined at this time.

Regulatory Matters

In 2009, the Georgia PSC voted to certify construction of Plant Vogtle Units 3 and 4 with a certified capital cost of $4.418 billion. In addition, in 2009 the Georgia PSC approved inclusion of the Plant Vogtle Units 3 and 4 related CWIP accounts in rate base, and the State of Georgia enacted the Georgia Nuclear Energy Financing Act, which allows Georgia Power to recover financing costs for Plant Vogtle Units 3 and 4. Financing costs are recovered on all applicable certified costs through annual adjustments to the NCCR tariff up to the certified capital cost of $4.418 billion. At December 31, 2018, Georgia Power had recovered approximately $1.9 billion of financing costs. Financing costs related to capital costs above $4.418 billion will be recovered through AFUDC; however, Georgia Power will not record AFUDC related to any capital costs in excess of the total deemed reasonable by the Georgia PSC (currently $7.3 billion) and not requested for rate recovery. On December 18, 2018, the Georgia PSC approved Georgia Power's request to increase the NCCR tariff by $88 million annually, effective January 1, 2019.

Georgia Power is required to file semi-annual VCM reports with the Georgia PSC by February 28 and August 31 of each year. In 2013, in connection with the eighth VCM report, the Georgia PSC approved a stipulation between Georgia Power and the staff of the Georgia PSC to waive the requirement to amend the Plant Vogtle Units 3 and 4 certificate in accordance with the 2009 certification order until the completion of Plant Vogtle Unit 3, or earlier if deemed appropriate by the Georgia PSC and Georgia Power.

In 2016, the Georgia PSC voted to approve a settlement agreement (Vogtle Cost Settlement Agreement) resolving certain prudency matters in connection with the fifteenth VCM report. In December 2017, the Georgia PSC voted to approve (and issued its related order on January 11, 2018) Georgia Power's seventeenth VCM report, which included a recommendation to continue construction with Southern Nuclear as project manager and Bechtel serving as the primary construction contractor, and modified the Vogtle Cost Settlement Agreement. The Vogtle Cost Settlement Agreement, as modified by the January 11, 2018 order, resolved the following regulatory matters related to Plant Vogtle Units 3 and 4: (i) none of the $3.3 billion of costs incurred through December 31, 2015 and reflected in the fourteenth VCM report should be disallowed from rate base on the basis of imprudence; (ii) the Contractor Settlement Agreement was reasonable and prudent and none of the amounts paid pursuant to the Contractor Settlement Agreement should be disallowed from rate base on the basis of imprudence; (iii) (a) capital costs incurred up to $5.68 billion would be presumed to be reasonable and prudent with the burden of proof on any party challenging such costs, (b) Georgia Power would have the burden to show that any capital costs above $5.68 billion were prudent, and (c) a revised capital cost forecast of $7.3 billion (after reflecting the impact of payments received under the Guarantee Settlement Agreement and related Customer Refunds) was found reasonable; (iv) construction of Plant Vogtle Units 3 and 4 should be completed, with Southern Nuclear serving as project manager and Bechtel as primary contractor; (v) approved and deemed reasonable Georgia Power's revised schedule placing Plant Vogtle Units 3 and 4 in service in November 2021 and November 2022, respectively; (vi) confirmed that the revised cost forecast does not represent a cost cap and that prudence decisions on cost recovery will be made at a later date, consistent with applicable Georgia law; (vii) reduced the ROE used to calculate the NCCR tariff (a) from 10.95% (the ROE rate setting point authorized by the Georgia PSC in the 2013 ARP) to 10.00% effective January 1, 2016, (b) from 10.00% to 8.30%, effective January 1, 2020, and (c) from 8.30% to 5.30%, effective January 1, 2021 (provided that the ROE in no case will be less than Georgia Power's average cost of long-term debt); (viii) reduced the ROE used for AFUDC equity for Plant Vogtle Units 3 and 4 from 10.00% to Georgia Power's average cost of long-term debt, effective January 1, 2018; and (ix) agreed that upon Unit 3 reaching commercial operation, retail base rates would be adjusted to include carrying costs on those capital costs deemed prudent in the Vogtle Cost Settlement Agreement. The January 11, 2018 order also stated that if Plant Vogtle Units 3 and 4 are not commercially operational by June 1, 2021 and June 1, 2022, respectively, the ROE used to calculate the NCCR tariff will be further reduced by 10 basis points each month (but not lower than Georgia Power's average cost of long-term debt) until the respective Unit is commercially operational. The ROE reductions negatively impacted earnings by approximately $100 million, $25 million, and $20 million in 2018, 2017, and 2016, respectively, and are estimated to have negative earnings impacts of approximately $75 million in 2019 and an aggregate of approximately $615 million from 2020 to 2022.

In its January 11, 2018 order, the Georgia PSC also stated if other conditions change and assumptions upon which Georgia Power's seventeenth VCM report are based do not materialize, the Georgia PSC reserved the right to reconsider the decision to continue construction.

On February 12, 2018, Georgia Interfaith Power & Light, Inc. (GIPL) and Partnership for Southern Equity, Inc. (PSE) filed a petition appealing the Georgia PSC's January 11, 2018 order with the Fulton County Superior Court. On March 8, 2018, Georgia Watch filed a similar appeal to the Fulton County Superior Court for judicial review of the Georgia PSC's decision and denial of Georgia Watch's motion for reconsideration. On December 21, 2018, the Fulton County Superior Court granted Georgia Power's motion to dismiss the two appeals. On January 9, 2019, GIPL, PSE, and Georgia Watch filed an appeal of this decision with the Georgia Court of Appeals. Georgia Power believes the appeal has no merit; however, an adverse outcome in the appeal combined with subsequent adverse action by the Georgia PSC could have a material impact on Southern Company's and Georgia Power's results of operations, financial condition, and liquidity.

In preparation for its nineteenth VCM filing, Georgia Power requested Southern Nuclear to perform a full cost reforecast for the project. This reforecast, performed prior to the nineteenth VCM filing, resulted in a $0.7 billion increase to the base capital cost forecast reported in the second quarter 2018. This base cost increase primarily resulted from changed assumptions related to the finalization of contract scopes and management responsibilities for Bechtel and over 60 subcontractors, labor productivity rates, and craft labor incentives, as well as the related levels of project management, oversight, and support, including field supervision and engineering support.

Although Georgia Power believes these incremental costs are reasonable and necessary to complete the project and the Georgia PSC's order in the seventeenth VCM proceeding specifically states that the construction of Plant Vogtle Units 3 and 4 is not subject to a cost cap, Georgia Power did not seek rate recovery for these cost increases included in the current base capital cost forecast (or any related financing costs) in the nineteenth VCM report. In connection with future VCM filings, Georgia Power may request the Georgia PSC to evaluate costs currently included in the construction contingency estimate for rate recovery as and when they are appropriately included in the base capital cost forecast. After considering the significant level of uncertainty that exists regarding the future recoverability of costs included in the construction contingency estimate since the ultimate outcome of these matters is subject to the outcome of future assessments by management, as well as Georgia PSC decisions in these future regulatory proceedings, Georgia Power recorded a total pre-tax charge to income of $1.1 billion ($0.8 billion after tax) in the second quarter 2018, which includes the total increase in the base capital cost forecast and construction contingency estimate.

On August 31, 2018, Georgia Power filed its nineteenth VCM report with the Georgia PSC, which requested approval of $578 million of construction capital costs incurred from January 1, 2018 through June 30, 2018. On February 19, 2019, the Georgia PSC approved the nineteenth VCM, but deferred approval of $51.6 million of expenditures related to Georgia Power's portion of an administrative claim filed in the Westinghouse bankruptcy proceedings. Through the nineteenth VCM, the Georgia PSC has approved total construction capital costs incurred through June 30, 2018 of $5.4 billion (before $1.7 billion of payments received under the Guarantee Settlement Agreement and approximately $188 million in related Customer Refunds). In addition, the staff of the Georgia PSC requested, and Georgia Power agreed, to file its twentieth VCM report concurrently with the twenty-first VCM report by August 31, 2019.

The ultimate outcome of these matters cannot be determined at this time.

DOE Financing

At December 31, 2018, Georgia Power had borrowed $2.6 billion related to Plant Vogtle Units 3 and 4 costs through the Loan Guarantee Agreement and a multi-advance credit facility among Georgia Power, the DOE, and the FFB, which provides for borrowings of up to $3.46 billion, subject to the satisfaction of certain conditions. In September 2017, the DOE issued a conditional commitment to Georgia Power for up to approximately $1.67 billion in additional guaranteed loans under the Loan Guarantee Agreement. In September 2018, the DOE extended the conditional commitment to March 31, 2019. Any further extension must be approved by the DOE. Final approval and issuance of these additional loan guarantees by the DOE cannot be assured and are subject to the negotiation of definitive agreements, completion of due diligence by the DOE, receipt of any necessary regulatory approvals, and satisfaction of other conditions. See Note 8 under "Long-term Debt – DOE Loan Guarantee Borrowings" for additional information, including applicable covenants, events of default, mandatory prepayment events (including any decision not to continue construction of Plant Vogtle Units 3 and 4), and conditions to borrowing.

The ultimate outcome of these matters cannot be determined at this time.

Mississippi Power

Regulatory Assets and Liabilities

Regulatory assets and (liabilities) reflected in the balance sheets of Mississippi Power at December 31, 2018 and 2017 relate to:

	2018			2017			Note
	(in millions)
Retiree benefit plans – regulatory assets	$	171		$	174		(a)
Asset retirement obligations	143			95			(b)
Kemper County energy facility assets, net	69			88			(c)
Remaining net book value of retired assets	41			44			(d)
Property tax	44			43			(e)
Deferred charges related to income taxes	34			36			(b)
Plant Daniel Units 3 and 4	36			36			(f)
ECO carryforward	26			26			(g)
Other regulatory assets	28			28			(h)
Deferred credits related to income taxes	(377		)	(377		)	(i)
Other cost of removal obligations	(185		)	(178		)	(b)
Property damage	(56		)	(57		)	(j)
Other regulatory liabilities	(9		)	—			(k)
Total regulatory assets (liabilities), net	$	(35	)	$	(42	)

Note: Unless otherwise noted, the recovery and amortization periods for these regulatory assets and (liabilities) are approved by the Mississippi PSC and are as follows:

(a) Recovered and amortized over the average remaining service period which may range up to 15 years. See Note 11 for additional information.

(b) Asset retirement and other cost of removal obligations and deferred charges related to income taxes are generally recovered over the related property lives, which may range up to 48 years. Asset retirement and other cost of removal obligations will be settled and trued up upon completion of removal activities over a period to be determined by the Mississippi PSC.

(c) Includes $91 million of regulatory assets and $22 million of regulatory liabilities. The retail portion includes $75 million of regulatory assets and $22 million of regulatory liabilities that are being recovered in rates over an eight-year period through 2025 and a six-year period through 2023, respectively. Recovery of the wholesale portion of the regulatory assets in the amount of $16 million is expected to be determined in a settlement agreement with wholesale customers in 2019. For additional information, see "Kemper County Energy Facility – Rate Recovery – Kemper Settlement Agreement" herein.

(d) Retail portion includes approximately $26 million being recovered over a five-year period through 2021 and 2022 for Plant Watson and Plant Greene County, respectively. Recovery of the wholesale portion of approximately $15 million is expected to be determined in a settlement agreement with wholesale customers in 2019.

(e) Recovered through the ad valorem tax adjustment clause over a 12-month period beginning in April of the following year. See "Ad Valorem Tax Adjustment" herein for additional information.

(f) Represents the difference between the revenue requirement under the purchase option and the revenue requirement assuming operating lease accounting treatment for the extended term, which will be amortized over a 10-year period beginning October 2021.

(g) Generally recovered through the ECO Plan clause in the year following the deferral. See "Environmental Compliance Plan" herein.

(h) Comprised of $9 million related to vacation pay, $8 million related to loss on reacquired debt, and other miscellaneous assets. These costs are recorded and recovered or amortized over periods which may range up to 50 years. This amount also includes fuel-hedging assets which are recorded over the life of the underlying hedged purchase contracts, which generally do not exceed three years. Upon final settlement, actual costs incurred are recovered through the ECM.

(i) Includes excess deferred income taxes primarily associated with Tax Reform Legislation of $377 million, of which $266 million is related to protected deferred income taxes to be recovered over the related property lives utilizing the average rate assumption method in accordance with IRS normalization principles and $111 million related to unprotected (not subject to normalization). The unprotected portion associated with the Kemper County energy facility is $46 million, of which $33 million is being amortized over eight years through 2025 for retail and the amortization of $15 million is expected to be determined in a settlement agreement with wholesale customers in 2019. Mississippi Power also has $9 million of excess deferred income tax benefits associated with the System Restoration Rider being amortized over an eight-year period through 2025. Amortization of the remaining portions of the unprotected deferred income taxes associated with the Tax Reform Legislation are expected to be determined in Mississippi Power's next base rate proceeding, which is scheduled to be filed in the fourth quarter 2019 (Mississippi Power 2019 Base Rate Case). See "Kemper County Energy Facility" and "FERC Matters – Mississippi Power – Municipal and Rural Associations Tariff" herein and Note 10 for additional information.

(j) For additional information, see "System Restoration Rider" herein.

(k) Comprised of numerous immaterial components including deferred income tax credits and other miscellaneous liabilities that are recorded and refunded or amortized generally over periods not exceeding one year.

Operations Review

In August 2018, the Mississippi PSC began an operations review of Mississippi Power, for which the final report is expected prior to the conclusion of the Mississippi Power 2019 Base Rate Case. Mississippi Power expects that the review will include, but not be limited to, a comparative analysis of its costs, its cost recovery framework, and ways in which it may streamline management operations for the reasonable benefit of ratepayers. The ultimate outcome of this matter cannot be determined at this time.

Performance Evaluation Plan

Mississippi Power's retail base rates generally are set under the PEP, a rate plan approved by the Mississippi PSC. Two filings are made for each calendar year: the PEP projected filing, which is typically filed prior to the beginning of the year based on a projected revenue requirement, and the PEP lookback filing, which is filed after the end of the year and allows for review of the actual revenue requirement compared to the projected filing.

In 2011, Mississippi Power submitted its annual PEP lookback filing for 2010, which recommended no surcharge or refund. Later in 2011, the MPUS disputed certain items in the 2010 PEP lookback filing. In 2012, the Mississippi PSC issued an order canceling Mississippi Power's PEP lookback filing for 2011. In 2013, the MPUS contested Mississippi Power's PEP lookback filing for 2012, which indicated a refund due to customers of$5 million. In 2014 through 2018, Mississippi Power submitted its annual PEP lookback filings for the prior years, which for each of 2013, 2014, and 2017 indicated no surcharge or refund and for each of 2015 and 2016 indicated a$5 millionsurcharge.Additionally, in July 2016, in November 2016, and in November 2017, Mississippi Power submitted its annual projected PEP filings for 2016, 2017, and 2018, respectively, which for 2016 and 2017 indicated no change in rates and for 2018 indicated a rate increase of 4%, or $38 millionin annual revenues. The Mississippi PSC suspended each of these filings to allow more time for review.

On February 7, 2018, Mississippi Power revised its annual projected PEP filing for 2018 to reflect the impacts of the Tax Reform Legislation. The revised filing requested an increase of$26 millionin annual revenues, based on a performance adjusted ROE of 9.33% and an increased equity ratio of 55%. On July 27, 2018, Mississippi Power and the MPUS entered into a settlement agreement, which was approved by the Mississippi PSC on August 7, 2018, with respect to the 2018 PEP filing and all unresolved PEP filings for prior years (PEP Settlement Agreement). Rates under the PEP Settlement Agreement became effective with the first billing cycle of September 2018. The PEP Settlement Agreement provides for an increase of approximately $21.6 millionin annual base retail revenues, which excludes certain compensation costs contested by the MPUS, as well as approximately$2 millionwhich was subsequently approved for recovery through the 2018 Energy Efficiency Cost Rider as discussed below. Under the PEP Settlement Agreement, Mississippi Power is deferring the contested compensation costs for 2018 and 2019 as a regulatory asset, which totaled$4 millionas of December 31, 2018 and is included in other regulatory assets, deferred on the balance sheet. The Mississippi PSC is currently expected to rule on the appropriate treatment for such costs in connection with the Mississippi Power 2019 Base Rate Case. The ultimate outcome of this matter cannot be determined at this time.

Pursuant to the PEP Settlement Agreement, Mississippi Power's performance-adjusted allowed ROE is9.31%and its allowed equity ratio is capped at51%, pending further review by the Mississippi PSC. In lieu of the requested equity ratio increase, Mississippi Power retained$44 millionof excess accumulated deferred income taxes resulting from the Tax Reform Legislation until the conclusion of the Mississippi Power 2019 Base Rate Case. Further, Mississippi Power agreed to seek equity contributions sufficient to restore its equity ratio to 50% by December 31, 2018. Since Mississippi Power's actual average equity ratio for 2018 was more than 1% lower than the 50%target, Mississippi Power deferred the corresponding difference in its revenue requirement of approximately $4 million as a regulatory liability for resolution in the Mississippi Power 2019 Base Rate Case.Pursuant to the PEP Settlement Agreement, PEP proceedings are suspended until after the conclusion of the Mississippi Power 2019 Base Rate Case and Mississippi Power is not required to make any PEP filings for regulatory years 2018, 2019, and 2020. The PEP Settlement Agreement also resolved all open PEP filings with no change to customer rates. As a result, in the third quarter 2018, Mississippi Power recognized revenues of$5 millionpreviously reserved in connection with the 2012 PEP lookback filing.

Energy Efficiency

In 2013, the Mississippi PSC approved an energy efficiency and conservation rule requiring electric and gas utilities in Mississippi serving more than25,000customers to implement energy efficiency programs and standards. Quick Start Plans, which include a portfolio of energy efficiency programs that are intended to provide benefits to a majority of customers, were extended by an order issued by the Mississippi PSC in July 2016, until the time the Mississippi PSC approves a comprehensive portfolio plan program. The ultimate outcome of this matter cannot be determined at this time.

On May 8, 2018, the Mississippi PSC issued an order approving Mississippi Power's revised annual projected Energy Efficiency Cost Rider 2018 compliance filing, which increased annual retail revenues by approximately $3 million effective with the first billing cycle for June 2018.

On February 5, 2019, the Mississippi PSC issued an order approving Mississippi Power's Energy Efficiency Cost Rider 2019 compliance filing, which included a slight decrease in annual retail revenues, effective with the first billing cycle in March 2019.

Environmental Compliance Overview Plan

In accordance with a 2011 accounting order from the Mississippi PSC, Mississippi Power has the authority to defer in a regulatory asset for future recovery all plant retirement- or partial retirement-related costs resulting from environmental regulations. The Mississippi PSC approved $41 million and $17 million of costs that were reclassified to regulatory assets associated with the fuel conversion of Plant Watson and Plant Greene County, respectively, for amortization over five-year periods that began in July 2016 and July 2017, respectively. As a result, these decisions are not expected to have a material impact on Mississippi Power's financial statements.

In August 2016, the Mississippi PSC approved Mississippi Power's revised ECO Plan filing for 2016, which requested the maximum2%annual increase in revenues, or approximately $18 million, primarily related to the Plant Daniel Units 1 and 2 scrubbers placed in service in 2015. The revised rates became effective with the first billing cycle for September 2016. Approximately$22 millionof related revenue requirements in excess of the 2%maximum was deferred for inclusion in the 2017 filing, along with related carrying costs.

In May 2017, the Mississippi PSC approved Mississippi Power's ECO Plan filing for 2017, which requested the maximum 2%annual increase in revenues, or approximately $18 million, primarily related to the carryforward from the prior year. The rates became effective with the first billing cycle for June 2017. Approximately $26 million, plus carrying costs, of related revenue requirements in excess of the 2%maximum was deferred for inclusion in the 2018 filing.

On February 14, 2018, Mississippi Power submitted its ECO Plan filing for 2018, including the effects of the Tax Reform Legislation, which requested the maximum 2%annual increase in revenues, or approximately$17 million, primarily related to the carryforward from the prior year.

On August 3, 2018, Mississippi Power and the MPUS entered into the ECO Settlement Agreement, which provides for an increase of approximately$17 millionin annual base retail revenues and was approved by the Mississippi PSC on August 7, 2018. Rates under the ECO Settlement Agreement became effective with the first billing cycle of September 2018 and will continue in effect until modified by the Mississippi PSC. These revenues are expected to be sufficient to recover the costs included in Mississippi Power's request for 2018, as well as the remaining deferred amounts, totaling $26 million at December 31, 2018, along with the related carrying costs. In accordance with the ECO Settlement Agreement, ECO Plan proceedings are suspended until after the conclusion of the Mississippi Power 2019 Base Rate Case and Mississippi Power is not required to make any ECO Plan filings for 2018, 2019, and 2020, with any necessary adjustments to be reflected in the Mississippi Power 2019 Base Rate Case. The ECO Settlement Agreement contains the same terms as the PEP Settlement Agreement described herein with respect to allowed ROE and equity ratio. At December 31, 2018, Mississippi Power has recorded $2 millionin other regulatory liabilities, deferred on the balance sheet related to the actual December 31, 2018 average equity ratio differential from target applicable to the ECO Plan.

Fuel Cost Recovery

Mississippi Power establishes, annually, a retail fuel cost recovery factor that is approved by the Mississippi PSC. Mississippi Power is required to file for an adjustment to the retail fuel cost recovery factor annually. In January 2017, the Mississippi PSC approved the 2017 retail fuel cost recovery factor, effective February 2017 through January 2018, which resulted in an annual revenue increase of $55 million. On January 16, 2018, the Mississippi PSC approved the 2018 retail fuel cost recovery factor, effective February 2018 through January 2019, which resulted in an annual revenue increase of $39 million. At December 31, 2018, the amount of over recovered retail fuel costs included in the balance sheet in other accounts payable was approximately$8 millioncompared to$6 millionunder recovered at December 31, 2017.On January 10, 2019, the Mississippi PSC approved the 2019 retail fuel cost recovery factor, effective February 2019, which results in a $35 milliondecrease in annual revenues as a result of lower expected fuel costs.

Mississippi Power's operating revenues are adjusted for differences in actual recoverable fuel cost and amounts billed in accordance with the currently approved cost recovery rate. Accordingly, changes in the billing factor should have no significant effect on Southern Company's or Mississippi Power's revenues or net income but will affect operating cash flows.

Ad Valorem Tax Adjustment

Mississippi Power establishes annually an ad valorem tax adjustment factor that is approved by the Mississippi PSC to collect the ad valorem taxes paid by Mississippi Power. In 2018, 2017, and 2016, the Mississippi PSC approved Mississippi Power's annual ad valorem tax adjustment factor filing, which included a rate increase of 0.8%, or $7 million, in 2018, a rate increase of 0.85%, or $8 million, in 2017, and a rate decrease of 0.07%, or $1 million, in 2016.

System Restoration Rider

Mississippi Power carries insurance for the cost of certain types of damage to generation plants and general property. However, Mississippi Power is self-insured for the cost of storm, fire, and other uninsured casualty damage to its property, including transmission and distribution facilities. As permitted by the Mississippi PSC and the FERC, Mississippi Power accrues for the cost of such damage through an annual expense accrual credited to regulatory liability accounts for the retail and wholesale jurisdictions. The cost of repairing actual damage resulting from such events that individually exceed $50,000 is charged to the reserve. Every three years the Mississippi PSC, the MPUS, and Mississippi Power will agree on SRR revenue level(s) for the ensuing period, based on historical data, expected exposure, type and amount of insurance coverage, excluding insurance cost, and any other relevant information. The accrual amount and the reserve balance are determined based on the SRR revenue level(s). If a significant change in circumstances occurs, then the SRR revenue level can be adjusted more frequently if Mississippi Power and the MPUS or the Mississippi PSC deem the change appropriate. The property damage reserve accrual will be the difference between the approved SRR revenues and the SRR revenue requirement, excluding any accrual to the reserve. In addition, SRR allows Mississippi Power to set up a regulatory asset, pending review, if the allowable actual retail property damage costs exceed the amount in the retail property damage reserve. Mississippi Power made retail accruals of $1 million, $3 million, and $4 million for 2018, 2017, and 2016, respectively. Mississippi Power also accrued $0.3 million annually in 2018, 2017, and 2016 for the wholesale jurisdiction. As of December 31, 2018, the property damage reserve balances were $55 million and $1 million for retail and wholesale, respectively.

Based on Mississippi Power's annual SRR rate filings, the SRR rate was zero for all years presented and Mississippi Power accrued $2 million, $4 million, and $3 million to the property damage reserve in 2018, 2017, and 2016, respectively. The SRR rate filings were suspended by the Mississippi PSC for review for a period not to exceed 120 days from their respective filing dates, after which the filings became effective.

In January 2017, a tornado caused extensive damage to Mississippi Power's transmission and distribution infrastructure. The cost of storm damage repairs was approximately $9 million. A portion of these costs was charged to the retail property damage reserve and addressed in the 2018 SRR rate filing.

Kemper County Energy Facility

Overview

The Kemper County energy facility was designed to utilize IGCC technology with an expected output capacity of 582 MWs and to be fueled by locally mined lignite (an abundant, lower heating value coal) from a mine owned by Mississippi Power and situated adjacent to the Kemper County energy facility. The mine, operated by North American Coal Corporation, started commercial operation in 2013. In connection with the Kemper County energy facility construction, Mississippi Power constructed approximately 61 miles of CO₂ pipeline infrastructure for the transport of captured CO₂ for use in enhanced oil recovery.

Schedule and Cost Estimate

In 2012, the Mississippi PSC issued an order (2012 MPSC CPCN Order), confirming the CPCN originally approved by the Mississippi PSC in 2010 authorizing the acquisition, construction, and operation of the Kemper County energy facility. The certificated cost estimate of the Kemper County energy facility included in the 2012 MPSC CPCN Order was $2.4 billion, net of approximately $0.57 billion for the cost of the lignite mine and equipment, the cost of the CO₂ pipeline facilities, AFUDC, and certain general exceptions (Cost Cap Exceptions). The 2012 MPSC CPCN Order approved a construction cost cap of up to $2.88 billion, with recovery of prudently-incurred costs subject to approval by the Mississippi PSC. The Kemper County energy facility was originally projected to be placed in service in May 2014. Mississippi Power placed the combined cycle and the associated common facilities portion of the Kemper County energy facility in service in August 2014. The combined cycle and associated common facilities portions of the Kemper County energy facility were dedicated as Plant Ratcliffe on April 27, 2018.

On June 21, 2017, the Mississippi PSC stated its intent to issue an order, which occurred on July 6, 2017, directing Mississippi Power to pursue a settlement under which the Kemper County energy facility would be operated as a natural gas plant, rather than an IGCC plant, and address all issues associated with the Kemper County energy facility. The order established a new docket for the purpose of pursuing a global settlement of the related costs (Kemper Settlement Docket). On June 28, 2017, Mississippi Power notified the Mississippi PSC that it would begin a process to suspend operations and start-up activities on the gasifier portion of the Kemper County energy facility, given the uncertainty as to its future.

At the time of project suspension in June 2017, the total cost estimate for the Kemper County energy facility was approximately $7.38 billion, including approximately $5.95 billion of costs subject to the construction cost cap, and was net of the $137 million in additional grants from the DOE received in April 2016. In the aggregate, Mississippi Power had recorded charges to income of $3.07 billion ($1.89 billion after tax) as a result of changes in the cost estimate above the cost cap for the Kemper IGCC through May 31, 2017.

Given the Mississippi PSC's stated intent regarding no further rate increase for the Kemper County energy facility and the subsequent suspension, cost recovery of the gasifier portions became no longer probable; therefore, Mississippi Power recorded an additional charge to income in June 2017 of $2.8 billion ($2.0 billion after tax), which included estimated costs associated with the gasification portions of the plant and lignite mine. During the third and fourth quarters of 2017, Mississippi Power recorded charges to income of $242 million ($206 million after tax), including $164 million for ongoing project costs, estimated mine and gasifier-related costs, and certain termination costs during the suspension period prior to conclusion of the Kemper Settlement Docket, as well as the charge associated with the Kemper Settlement Agreement discussed below.

In 2018, Mississippi Power recorded pre-tax charges to income of $37 million ($27 million after tax), primarily resulting from the abandonment and related closure activities and ongoing period costs, net of sales proceeds, for the mine and gasifier-related assets at the Kemper County energy facility. In addition, Mississippi Power recorded a credit to earnings of $95 millionin the fourth quarter 2018 primarily resulting from the reduction of a valuation allowance for a state income tax NOL carryforward associated with the Kemper County energy facility. Additional closure costs for the mine and gasifier-related assets, currently estimated at up to $10 million pre-tax (excluding salvage, net of dismantlement costs), may be incurred through the first half of 2020. In addition, period costs, including, but not limited to, costs for compliance and safety, ARO accretion, and property taxes for the mine and gasifier-related assets, are estimated to total $11 millionin 2019 and$2 million to $4 millionannually in 2020 through 2023. Mississippi Power is currently evaluating its options regarding the final disposition of the CO₂ pipeline, including removal of the pipeline. This evaluation is expected to be complete later in 2019. If Mississippi Power ultimately decides to remove the CO₂ pipeline, the cost of removal would have a material impact on Mississippi Power's financial statements and could have a material impact on Southern Company's financial statements. The ultimate outcome of these matters cannot be determined at this time.

See Note 10 for additional information.

Rate Recovery

Kemper Settlement Agreement

In 2015, the Mississippi PSC issued an order (In-Service Asset Rate Order) regarding the Kemper County energy facility assets that were commercially operational and providing service to customers (the transmission facilities, combined cycle, natural gas pipeline, and water pipeline) and other related costs. The In-Service Asset Rate Order provided for retail rate recovery of an annual revenue requirement of approximately $126 million which went into effect on December 17, 2015.

On February 6, 2018, the Mississippi PSC voted to approve a settlement agreement related to cost recovery for the Kemper County energy facility among Mississippi Power, the MPUS, and certain intervenors (Kemper Settlement Agreement), which resolved all cost recovery issues, modified the CPCN to limit the Kemper County energy facility to natural gas combined cycle operation, and provided for an annual revenue requirement of approximately $99.3 million for costs related to the Kemper County energy facility, which included the impact of the Tax Reform Legislation. The revenue requirement is based on (i) a fixed ROE for 2018 of 8.6% excluding any performance adjustment, (ii) a ROE for 2019 calculated in accordance with PEP, excluding the performance adjustment, (iii) for future years, a performance-based ROE calculated pursuant to PEP, and (iv) amortization periods for the related regulatory assets and liabilities of eight years and six years, respectively. The revenue requirement also reflects a disallowance related to a portion of Mississippi Power's investment in the Kemper County energy facility requested for inclusion in rate base, which was recorded in the fourth quarter 2017 as an additional charge to income of approximately $78 million ($85 million net of accumulated depreciation of $7 million) pre-tax ($48 million after tax).

Under the Kemper Settlement Agreement, retail customer rates reflect a reduction of approximately $26.8 million annually, effective with the first billing cycle of April 2018, and include no recovery for costs associated with the gasifier portion of the Kemper County energy facility in 2018 or at any future date.

Reserve Margin Plan

On August 6, 2018, Mississippi Power filed its proposed Reserve Margin Plan (RMP), as required by the Mississippi PSC's order in the Kemper Settlement Docket. Under the RMP, Mississippi Power proposed alternatives that would reduce its reserve margin, with the most economic of the alternatives being thetwo-year and seven-year acceleration of the retirement of Plant Watson Units 4 and 5, respectively, to the first quarter 2022 and the four-year acceleration of the retirement of Plant Greene County Units 1 and 2 to the third quarter 2021 and the third quarter 2022, respectively, in order to lower or avoid operating costs. The Plant Greene County unit retirements would require the completion by Alabama Power of proposed transmission and system reliability improvements, as well as agreement by Alabama Power. The RMP filing also states that, in the event the Mississippi PSC ultimately approves an alternative that includes an accelerated retirement, Mississippi Power would require authorization to defer in a regulatory asset for future recovery the remaining net book value of the units at the time of retirement. A decision by the Mississippi PSC that does not include recovery of the remaining book value of any generating units retired could have a material impact on Mississippi Power's and Southern Company's financial statements. The ultimate outcome of this matter cannot be determined at this time.

Lignite Mine and CO₂ Pipeline Facilities

Mississippi Power owns the lignite mine and equipment and mineral reserves located around the Kemper County energy facility site. The mine started commercial operation in June 2013.

In 2010, Mississippi Power executed a 40-year management fee contract with Liberty Fuels Company, LLC (Liberty Fuels), a wholly-owned subsidiary of The North American Coal Corporation, which developed, constructed, and is responsible for the mining operations through the end of the mine reclamation. As the mining permit holder, Liberty Fuels has a legal obligation to perform mine reclamation and Mississippi Power has a contractual obligation to fund all reclamation activities. As a result of the abandonment of the Kemper IGCC, final mine reclamation began in 2018 and is expected to be substantially completed in 2020, with monitoring expected to continue through 2027. See Note 6 and Note 7 under "Mississippi Power" for additional information.

In addition, Mississippi Power constructed the CO₂ pipeline for the planned transport of captured CO₂ for use in enhanced oil recovery and entered into an agreement with Denbury Onshore (Denbury) to purchase the captured CO₂. The agreement with Denbury was terminated in December 2018 and did not have a material impact on Southern Company's or Mississippi Power's results of operations. Mississippi Power is currently evaluating its options regarding the final disposition of the CO₂ pipeline, including removal of the pipeline. This evaluation is expected to be complete later in 2019. If Mississippi Power ultimately decides to remove the CO₂ pipeline, the cost of removal would have a material impact on Mississippi Power's financial statements and could have a material impact on Southern Company's financial statements. The ultimate outcome of this matter cannot be determined at this time.

Government Grants

In 2010, the DOE, through a cooperative agreement with SCS, agreed to fund $270 million of the Kemper County energy facility through the grants awarded to the project by the DOE under the Clean Coal Power Initiative Round 2. Through December 31, 2018, Mississippi Power received total DOE grants of $387 million, of which $382 million reduced the construction costs of the Kemper County energy facility and $5 million reimbursed Mississippi Power for expenses associated with DOE reporting. On December 12, 2018, Mississippi Power filed with the DOE its request for property closeout certification under the contract related to the grants received. Mississippi Power and the DOE are currently in discussions regarding the requested closeout and property disposition, which may require payment to the DOE for a portion of certain property that is to be retained by Mississippi Power. The ultimate outcome of this matter cannot be determined at this time; however, it could have a material impact on Mississippi Power's financial statements and a significant impact on Southern Company's financial statements.

Southern Company Gas

Regulatory Assets and Liabilities

Regulatory assets and (liabilities) reflected in the balance sheets of Southern Company Gas at December 31, 2018 and 2017 relate to:

	2018			2017			Note
	(in millions)
Environmental remediation	$	311		$	410		(a,b)
Retiree benefit plans	161			270			(a,c)
Long-term debt fair value adjustment	121			138			(d)
Under recovered regulatory clause revenues	90			98			(e)
Other regulatory assets	59			79			(f)
Other cost of removal obligations	(1,585		)	(1,646		)	(g)
Deferred income tax credits	(940		)	(1,063		)	(g,i)
Over recovered regulatory clause revenues	(43		)	(144		)	(e)
Other regulatory liabilities	(46		)	(21		)	(h)
Total regulatory assets (liabilities), net	$	(1,872	)	$	(1,879	)

Note: Unless otherwise noted, the recovery and amortization periods for these regulatory assets and (liabilities) have been approved or accepted by the relevant state PSC or other regulatory body and are as follows:

(a) Not earning a return as offset in rate base by a corresponding asset or liability.

(b) Recovered through environmental cost recovery mechanisms when the remediation is performed or the work is performed.

(c) Recovered and amortized over the average remaining service period which range up to 15 years. See Note 11 for additional information.

(d) Recovered over the remaining life of the original debt issuances, which range up to 20 years.

(e) Recorded and recovered or amortized over periods generally not exceeding seven years. In addition to natural gas cost recovery mechanisms, the natural gas distribution utilities are authorized to utilize other cost recovery mechanisms, such as regulatory riders, which vary by utility but allow recovery of certain costs, such as those related to infrastructure replacement programs, as well as environmental remediation and energy efficiency plans.

(f) Comprised of several components including unamortized loss on reacquired debt, weather normalization, franchise gas, deferred depreciation, and financial instrument-hedging assets, which are recovered or amortized over periods generally not exceeding 10 years, except for financial hedging-instruments. Financial instrument-hedging assets are recorded over the life of the underlying hedged purchase contracts, which generally do not exceed two years. Upon final settlement, actual costs incurred are recovered, and actual income earned is refunded through the energy cost recovery clause.

(g) Other cost of removal obligations are recorded and deferred income tax liabilities are amortized over the related property lives, which may range up to 80 years. Cost of removal liabilities will be settled and trued up following completion of the related activities.

(h) Comprised of several components including amounts to be refunded to customers as a result of the Tax Reform Legislation, energy efficiency programs, and unamortized bond issuance costs and financial instrument-hedging liabilities which are recovered or amortized over periods generally not exceeding 20 years, except for financial hedging-instruments. Financial instrument-hedging liabilities are recorded over the life of the underlying hedged purchase contracts, which generally do not exceed two years. Upon final settlement, actual costs incurred are recovered, and actual income earned is refunded through the energy cost recovery clause. See "Rate Proceedings" herein for additional information regarding customer refunds resulting from the Tax Reform Legislation.

(i) Includes excess deferred income tax liabilities not subject to normalization as a result of the Tax Reform Legislation, the recovery and amortization of which is expected to be determined by the applicable state regulatory agencies in future rate proceedings. See "Rate Proceedings" herein and Note 10 for additional details.

Infrastructure Replacement Programs and Capital Projects

In addition to capital expenditures recovered through base rates by each of the natural gas distribution utilities, Nicor Gas and Virginia Natural Gas have separate rate riders that provide timely recovery of capital expenditures for specific infrastructure replacement programs. Descriptions of the infrastructure replacement programs and capital projects at the natural gas distribution utilities follow:

Nicor Gas

In 2013, Illinois enacted legislation that allows Nicor Gas to provide more widespread safety and reliability enhancements to its distribution system. The legislation stipulates that rate increases to customers as a result of any infrastructure investments shall not exceed a cumulative annual average of 4.0% or, in any given year, 5.5% of base rate revenues. In 2014, the Illinois Commission approved the nine-year regulatory infrastructure program, Investing in Illinois, subject to annual review. In conjunction with the base rate case order issued by the Illinois Commission on January 31, 2018, Nicor Gas is recovering program costs incurred prior to December 31, 2017 through base rates. Nicor Gas has requested that the program costs incurred subsequent to December 31, 2017, which are currently being recovered through a separate rider, be addressed in the base rate case filed November 9, 2018. See "Rate Proceedings" herein for additional information.

Virginia Natural Gas

In 2012, the Virginia Commission approved the Steps to Advance Virginia's Energy (SAVE) program, an accelerated infrastructure replacement program, to be completed over a five-year period. In 2016, the Virginia Commission approved an extension to the SAVE program for Virginia Natural Gas to replace more than 200 miles of aging pipeline infrastructure and invest up to $30 million in 2016 and up to $35 million annually through 2021.

The SAVE program is subject to annual review by the Virginia Commission. In conjunction with the base rate case order issued by the Virginia Commission in December 2017, Virginia Natural Gas is recovering program costs incurred prior to September 1, 2017 through base rates. Program costs incurred subsequent to September 1, 2017 are currently recovered through a separate rider and are subject to future base rate case proceedings.

Atlanta Gas Light

GRAM

In February 2017, the Georgia PSC approved GRAM and a $20 million increase in annual base rate revenues for Atlanta Gas Light, effective March 1, 2017. GRAM adjusts base rates annually, up or down, using an earnings band based on the previously approved ROE of 10.75% and does not collect revenue through special riders and surcharges. Atlanta Gas Light adjusts rates up to the lower end of the band of 10.55% and adjusts rates down to the higher end of the band of 10.95%. Various infrastructure programs previously authorized by the Georgia PSC under Atlanta Gas Light's STRIDE program including the Integrated Vintage Plastic Replacement Program to replace aging plastic pipe and the Integrated System Reinforcement Program to upgrade Atlanta Gas Light's distribution system and LNG facilities in Georgia continue under GRAM and the recovery of and return on the infrastructure program investments are included in annual base rate adjustments. The Georgia PSC reviews Atlanta Gas Light's performance annually under GRAM. See Rate Proceedings" herein for additional information.

Pursuant to the GRAM approval, Atlanta Gas Light and the staff of the Georgia PSC agreed to a variation of the Integrated Customer Growth Program to extend pipeline facilities to serve customers in areas without pipeline access and create new economic development opportunities in Georgia, which was formerly part of the STRIDE program. As a result, a new tariff was created, effective October 10, 2017, to provide up to $15 million annually for Atlanta Gas Light to commit to strategic economic development projects. Projects under this tariff must be approved by the Georgia PSC.

The orders for the STRIDE program provide for recovery of all prudent costs incurred in the performance of the program. Atlanta Gas Light will recover from end-use customers, through billings to Marketers, the costs related to the program, net of any related cost savings. The regulatory asset represents incurred program costs that will be collected through GRAM. The future expected costs to be recovered through rates related to allowed, but not incurred, costs are recognized in an unrecognized ratemaking amount that is not reflected on the balance sheets. This allowed cost is primarily the equity return on the capital investment under the program. See "Unrecognized Ratemaking Amounts"herein for additional information.

Atlanta Gas Light capitalizes and depreciates the capital expenditure costs incurred from the STRIDE programs over the life of the assets. Operations and maintenance costs are expensed as incurred. Recoveries, which are recorded as revenue, are based on a formula that allows Atlanta Gas Light to recover operations and maintenance costs in excess of those included in its current base rates, depreciation, and an allowed rate of return on capital expenditures. However, Atlanta Gas Light is allowed the recovery of carrying costs on the under recovered balance resulting from the timing difference.

PRP

In 2015, Atlanta Gas Light began recovering incremental PRP surcharge amounts through three phased-in increases in addition to its already existing PRP surcharge amount, which was established to address recovery of the under recovered PRP balance of $144 million and the estimated amounts to be earned under the program through 2025. The unrecovered balance is the result of the continued revenue requirement earned under the program offset by the existing and incremental PRP surcharges. The under recovered balance at December 31, 2018 was $171 million, including $95 million of unrecognized equity return. The PRP surcharge will remain in effect until the earlier of the full recovery of the under recovered amount or December 31, 2025. See "Rate Proceedings" and "Unrecognized Ratemaking Amounts" herein for additional information.

One of the capital projects under the PRP experienced construction issues and Atlanta Gas Light was required to complete mitigation work prior to placing it in service. These mitigation costs were included in base rates in 2018. In 2017, Atlanta Gas Light recovered $20 million from the settlement of contractor litigation claims and recovered an additional $7 million from the final settlement of contractor litigation claims during the first quarter 2018. Mitigation costs recovered through the legal process are retained by Atlanta Gas Light.

Natural Gas Cost Recovery

With the exception of Atlanta Gas Light, the natural gas distribution utilities are authorized by the relevant regulatory agencies in the states in which they serve to use natural gas cost recovery mechanisms that adjust rates to reflect changes in the wholesale cost of natural gas and ensure recovery of all costs prudently incurred in purchasing natural gas for customers. Natural gas cost recovery revenues are adjusted for differences in actual recoverable natural gas costs and amounts billed in current regulated rates. Changes in the billing factor will not have a significant effect on Southern Company's or Southern Company Gas' revenues or net income, but will affect cash flows.

Rate Proceedings

Nicor Gas

On January 31, 2018, the Illinois Commission approved a $137 million increase in annual base rate revenues, including $93 million related to the recovery of investments under the Investing in Illinois program, effective February 8, 2018, based on a ROE of 9.8%.

On April 19, 2018, the Illinois Commission approved Nicor Gas' variable income tax adjustment rider. This rider provides for refund or recovery of changes in income tax expense that result from income tax rates that differ from those used in Nicor Gas' last rate case. Customer refunds, via bill credits, related to the impacts of the Tax Reform Legislation from January 25, 2018 through May 4, 2018 began on July 1, 2018 and are expected to conclude in the second quarter 2019.

On May 2, 2018, the Illinois Commission approved Nicor Gas' rehearing request for revised base rates to incorporate the reduction in the federal income tax rate as a result of the Tax Reform Legislation. The resulting decrease of approximately $44 million in annual base rate revenues became effective May 5, 2018. Nicor Gas' previously-authorized capital structure and ROE of 9.80% were not addressed in the rehearing and remain unchanged.

On November 9, 2018, Nicor Gas filed a general base rate case with the Illinois Commission requesting a $230 million increase in annual base rate revenues. The requested increase is based on a projected test year for the 12-month period ending September 30, 2020, a ROE of 10.6%, and an increase in the equity ratio from 52.0% to 54.0% to address the negative cash flow and credit metric impacts of the Tax Reform Legislation. The Illinois Commission is expected to rule on the requested increase within the 11-month statutory time limit, after which rate adjustments will be effective. The ultimate outcome of this matter cannot be determined at this time.

Atlanta Gas Light

On February 23, 2018, Atlanta Gas Light revised its annual base rate filing to reflect the impacts of the Tax Reform Legislation and requested a $16 million rate reduction in 2018. On May 15, 2018, the Georgia PSC approved a stipulation for Atlanta Gas Light's annual base rates to remain at the 2017 level for 2018 and 2019, with customer credits of $8 million in each of July 2018 and October 2018 to reflect the impacts of the Tax Reform Legislation. The Georgia PSC maintained Atlanta Gas Light's previously authorized earnings band based on a ROE between 10.55% and 10.95% and increased the allowed equity ratio by 4% to an equity ratio of 55% to address the negative cash flow and credit metric impacts of the Tax Reform Legislation. Additionally, Atlanta Gas Light is required to file a traditional base rate case on or before June 1, 2019 for rates effective January 1, 2020.

Atlanta Gas Light's recovery of the previously unrecovered PRP revenue through 2014, as well as the mitigation costs associated with the PRP that were not previously included in its rates, were included in GRAM. In connection with the GRAM approval, the last monthly PRP surcharge increase became effective March 1, 2017.

Virginia Natural Gas

On December 21, 2017, the Virginia Commission approved a settlement for a $34 million increase in annual base rate revenues, effective September 1, 2017, including $13 million related to the recovery of investments under the SAVE program. See "Regulatory Infrastructure Programs" herein for additional information. An authorized ROE range of 9.0% to 10.0% with a midpoint of 9.5% will be used to determine the revenue requirement in any filing, other than for a change in base rates.

On December 17, 2018, the Virginia Commission approved Virginia Natural Gas' annual information form filing, which reduced annual base rates by $14 million effective January 1, 2019 due to lower tax expense as a result of the lower corporate income tax rate and the impact of the flowback of excess deferred income taxes. This approval also requires Virginia Natural Gas to issue customer refunds, via bill credits, for the entire $14 million which was deferred as a regulatory liability, current, on the balance sheet at December 31, 2018. These customer refunds are expected to be completed in the first quarter 2019.

energySMART

The Illinois Commission approved Nicor Gas' energySMART program, which includes energy efficiency program offerings and therm reduction goals. Through December 31, 2017, Nicor Gas spent $107 million of the initial authorized expenditure of $113 million. A new program began on January 1, 2018, with an additional authorized expenditure of $160 million through 2021. Through December 31, 2018, Nicor Gas had spent $29 million.

Unrecognized Ratemaking Amounts

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, 2018		December 31, 2017
	(in millions)
Atlanta Gas Light	$	95	$	104
Virginia Natural Gas	11		11
Nicor Gas	4		2
Total	$	110	$	117

FERC Matters

Open Access Transmission Tariff

On May 10, 2018, AMEA and Cooperative Energy filed with the FERC a complaint against SCS and the traditional electric operating companies claiming that the current 11.25% base ROE used in calculating the annual transmission revenue requirements of the traditional electric operating companies' open access transmission tariff is unjust and unreasonable as measured by the applicable FERC standards. The complaint requested that the base ROE be set no higher than 8.65% and that the FERC order refunds for the difference in revenue requirements that results from applying a just and reasonable ROE established in this proceeding upon determining the current ROE is unjust and unreasonable. On June 18, 2018, SCS and the traditional electric operating companies filed their response challenging the adequacy of the showing presented by the complainants and offering support for the current ROE. On September 6, 2018, the FERC issued an order establishing a refund effective date of May 10, 2018 in the event a refund is due and initiating an investigation and settlement procedures regarding the current base ROE. Through December 31, 2018, the estimated maximum potential refund is not expected to be material to Southern Company's or the traditional electric operating companies' results of operations or cash flows. The ultimate outcome of this matter cannot be determined at this time.

Mississippi Power

Municipal and Rural Associations Tariff

Mississippi Power provides wholesale electric service to Cooperative Energy, East Mississippi Electric Power Association, and the City of Collins, all located in southeastern Mississippi, under a long-term cost-based, FERC-regulated MRA tariff.

In 2016, Mississippi Power reached a settlement agreement with its wholesale customers, which was subsequently approved by the FERC, for an increase in wholesale base revenues under the MRA cost-based electric tariff, primarily as a result of placing scrubbers for Plant Daniel Units 1 and 2 in service in 2015. The settlement agreement became effective for services rendered beginning May 1, 2016, resulting in an estimated annual revenue increase of $7 million under the MRA cost-based electric tariff. Additionally, under the settlement agreement, the tariff customers agreed to similar regulatory treatment for MRA tariff ratemaking as the treatment approved for retail ratemaking under the In-Service Asset Rate Order. This regulatory treatment primarily included (i) recovery of the operational Kemper County energy facility assets providing service to customers and other related costs, (ii) amortization of the Kemper County energy facility-related regulatory assets included in rates under the settlement agreement over the 36 monthsending April 30, 2019, (iii) Kemper County energy facility-related expenses included in rates under the settlement agreement no longer being deferred and charged to expense, and (iv) removing all of the Kemper County energy facility CWIP from rate base with a corresponding increase in accrual of AFUDC, which totaled approximately$22 millionthrough the suspension of Kemper IGCC start-up activities.

Mississippi Power expects to reach a subsequent settlement agreement with its wholesale customers and will make a filing with the FERC during the first quarter 2019. The settlement agreement is intended to be consistent with the Kemper Settlement Agreement, including the impact of the Tax Reform Legislation. The ultimate outcome of this matter cannot be determined at this time.

In September 2017, Mississippi Power and Cooperative Energy executed a Shared Service Agreement (SSA), as part of the MRA tariff, under which Mississippi Power and Cooperative Energy will share in providing electricity to all Cooperative Energy delivery points, in lieu of the current arrangement under which each delivery point is specifically assigned to either entity. The SSA accepted by the FERC in October 2017 became effective on January 1, 2018 and may be cancelled by Cooperative Energy with10 years notice after December 31, 2020.The SSA provides Cooperative Energy the option to decrease its use of Mississippi Power's generation services under the MRA tariff, subject to annual and cumulative caps and aone-year notice requirement. In the event Cooperative Energy elects to reduce these services, the related reduction in Mississippi Power's revenues is not expected to be significant through 2020.

Fuel Cost Recovery

Mississippi Power has a wholesale MRA and a Market Based (MB) fuel cost recovery factor. Effective with the first billing cycle for January 2018, fuel rates increased$11 millionannually for wholesale MRA customers and$1 millionannually for wholesale MB customers. Effective January 1, 2019, the wholesale MRA fuel rate decreased$16 millionannually and the wholesale MB fuel rate decreased by an immaterial amount. At December 31, 2018, over recovered wholesale MRA fuel costs included in other regulatory liabilities, current on the balance sheet were approximately$6 millioncompared to an immaterial amount at December 31, 2017. Under recovered wholesale MB fuel costs included in the balance sheets were immaterial at December 31, 2018 and 2017.

Mississippi Power's operating revenues are adjusted for differences in actual recoverable fuel cost and amounts billed in accordance with the currently approved cost recovery rate. Accordingly, changes in the billing factor should have no significant effect on Mississippi Power's revenues or net income, but will affect cash flow.

Southern Company Gas

At December 31, 2018, Southern Company Gas was involved in two gas pipeline construction projects. These projects, along with Southern Company Gas' existing pipelines, are intended to provide diverse sources of natural gas supplies to customers, resolve current and long-term supply planning for new capacity, enhance system reliability, and generate economic development in the areas served.

On January 19, 2018, the PennEast Pipeline received FERC approval. Work continues with state and federal agencies to obtain the required permits to begin construction. Any material delays may impact forecasted capital expenditures and the expected in-service date.

In October 2017, the Atlantic Coast Pipeline received FERC approval. This joint venture has experienced challenges to its permits since construction began in 2018. During the third and fourth quarters 2018, a FERC stop work order, together with delays in obtaining permits necessary for construction and construction delays due to judicial actions, impacted the cost and schedule for the project. As a result, total project cost estimates have increased from between $6.0 billion and $6.5 billion to between $7.0 billion and $7.8 billion, excluding financing costs. Southern Company Gas' share of the total project costs is 5% and Southern Company Gas' investment at December 31, 2018 totaled $83 million. The operator of the joint venture currently expects to achieve a late 2020 in-service date for at least key segments of the Atlantic Coast Pipeline, while the remainder may extend into early 2021. Southern Company Gas has evaluated the recoverability of its investment and determined there was no impairment as of December 31, 2018. Abnormal weather, work delays (including due to judicial or regulatory action), and other conditions may result in additional cost or schedule modifications, which could result in an impairment of Southern Company Gas' investment and could have a material impact on Southern Company's and Southern Company Gas' financial statements.

The ultimate outcome of these matters cannot be determined at this time. See Notes 7 and 9 under "Southern Company Gas – Equity Method Investments" and "Guarantees," respectively, for additional information on these pipeline projects.