REGULATORY MATTERS

General

IPL is subject to regulation by the IURC as to its services and facilities, the valuation of property, the construction, purchase, or lease of electric generating facilities, the classification of accounts, rates of depreciation, retail rates and charges, the issuance of securities (other than evidences of indebtedness payable less than twelve months after the date of issue), the acquisition and sale of some public utility properties or securities and certain other matters.

In addition, IPL is subject to the jurisdiction of the FERC with respect to, among other things, short-term borrowings not regulated by the IURC, the sale of electricity at wholesale, the transmission of electric energy in interstate commerce, the classification of accounts, reliability standards, and the acquisition and sale of utility property in certain circumstances as provided by the Federal Power Act. As a regulated entity, IPL is required to use certain accounting methods prescribed by regulatory bodies which may differ from those accounting methods required to be used by unregulated entities.

IPL is also affected by the regulatory jurisdiction of the EPA at the federal level, and the IDEM at the state level. Other significant regulatory agencies affecting IPL include, but are not limited to, the NERC, the U.S. Department of Labor and the IOSHA.

Basic Rates and Charges

Our basic rates and charges represent the largest component of our annual revenues. Our basic rates and charges are determined after giving consideration, on a pro-forma basis, to all allowable costs for ratemaking purposes including a fair return on the fair value of the utility property used and useful in providing service to customers. These basic rates and charges are set and approved by the IURC after public hearings. Such proceedings, which have occurred at irregular intervals, involve IPL, the IURC, the Indiana Office of Utility Consumer Counselor, and other interested stakeholders. Pursuant to statute, the IURC is to conduct a periodic review of the basic rates and charges of all Indiana utilities at least once every four years, but the IURC has the authority to review the rates of any Indiana utility at any time. Once set, the basic rates and charges authorized do not assure the realization of a fair return on the fair value of property.

Our declining block rate structure generally provides for residential and commercial customers to be charged a lower per kWh rate at higher consumption levels. Therefore, as volumes increase, the weighted average price per kWh decreases. Numerous factors including, but not limited to, weather, inflation, customer growth and usage, the level of actual operating and maintenance expenditures, fuel costs, generating unit availability, and capital expenditures including those required by environmental regulations can affect the return realized.

Base Rate Orders

On October 31, 2018, the IURC issued an order approving an uncontested settlement agreement previously filed with the IURC by IPL for a $43.9 million, or 3.2%, increase to annual revenues (the "2018 Base Rate Order"). The 2018 Base Rate Order includes recovery through rates of the CCGT at Eagle Valley completed in the first half of 2018, as well as other construction projects and changes to operating income since the 2016 Base Rate Order (See below). New basic rates and charges became effective on December 5, 2018. The 2018 Base Rate Order also provides customers approximately $50 million in benefits, which are flowing to customers over the two-year period that began March 2019, via the ECCRA rate adjustment mechanism. This liability, less amounts returned to IPL's customers during 2019, is recorded primarily in "Regulatory liabilities, current" with approximately $4.7 million in "Regulatory liabilities, non-current" as of December 31, 2019 on the accompanying Consolidated Balance Sheets. In addition, the 2018 Base Rate Order provides that annual wholesale margins earned above (or below) the benchmark of $16.3 million shall be passed back (or charged) to customer rates through a rate adjustment mechanism. Similarly, the 2018 Base Rate Order provides that all capacity sales above (or below) a benchmark of $11.3 million shall be passed back (or charged) to customer rates through a rate adjustment mechanism. The 2018 Base Rate Order also approved changes to IPL's depreciation and amortization rates (including no longer deferring depreciation on the CCGT at Eagle Valley) which altogether represent a net expense increase of approximately $28.7 million annually.

In March 2016, the IURC issued the 2016 Base Rate Order authorizing IPL to increase its basic rates and charges by $30.8 million annually. IPL also received approval to implement three new rate riders for current recovery from customers of ongoing MISO costs and capacity costs, and for sharing with customers 50% of wholesale sales margins above and below the established benchmark of $6.3 million.

CCR

On April 26, 2017, the IURC approved IPL’s CCR compliance request to install a bottom ash dewatering system at its Petersburg generating station and to recover 80% of qualifying costs through a rate adjustment mechanism with the remainder recorded as a regulatory asset for recovery in a subsequent rate case. The approved capital cost of the CCR compliance plan was approximately $47 million. IPL’s bottom ash dewatering system at its Petersburg generating station went into service in September 2017.

NAAQS

On April 26, 2017, the IURC approved IPL’s request for NAAQS SO₂ compliance at its Petersburg generation station with 80% of qualifying costs recovered through a rate adjustment mechanism and the remainder recorded

as a regulatory asset for recovery in a subsequent rate case. The approved capital cost of the NAAQS SO₂ compliance plan was approximately $29 million. These projects went into service between August 2018 and August 2019.

Other

The DOE issued a Notice of Proposed Rule Making on September 29, 2017, which directed the FERC to exercise its authority to set just and reasonable rates that recognize the “resiliency” value provided by generation plants with certain characteristics, including having 90-days or more of on-site fuel and operating in markets where they do not receive rate base treatment through state ratemaking. Nuclear and coal-fired generation plants would have been most likely to be able to meet the requirements. As proposed, the DOE would value resiliency through rates that recover “compensable costs” that were defined to include the recovery of operating and fuel expenses, debt service and a fair return on equity. On January 8, 2018, the FERC issued an order terminating this docket stating that it failed to satisfy the legal requirements of Section 206 of the Federal Power Act of 1935. The FERC initiated a new docket to take additional steps to explore resilience issues in RTOs/ISOs. The goal of this new proceeding is to: (1) develop a common understanding among the FERC, State Commissions, RTOs/ISOs, transmission owners, and others as to what resilience of the bulk power system means and requires; (2) understand how each RTO and ISO assesses resilience in its geographic footprint; and (3) use this information to evaluate whether additional action regarding resilience is appropriate at this time. It is not possible to predict the impact of this proceeding on our business, financial condition and results of operations.

FAC and Authorized Annual Jurisdictional Net Operating Income

IPL may apply to the IURC for a change in IPL’s fuel charge every three months to recover IPL’s estimated fuel costs, including the energy portion of purchased power costs, which may be above or below the levels included in IPL’s basic rates and charges. IPL must present evidence in each FAC proceeding that it has made every reasonable effort to acquire fuel and generate or purchase power or both so as to provide electricity to its retail customers at the lowest fuel cost reasonably possible.

Independent of the IURC’s ability to review basic rates and charges, Indiana law requires electric utilities under the jurisdiction of the IURC to meet operating expense and income test requirements as a condition for approval of requested changes in the FAC. A utility may be unable to recover all of its fuel costs if its rolling twelve-month operating income, determined at quarterly measurement dates, exceeds its authorized annual jurisdictional net operating income and there are not sufficient applicable cumulative net operating income deficiencies (“Cumulative Deficiencies”) to offset it. The Cumulative Deficiencies calculation provides that only five years’ worth of historical earnings deficiencies or surpluses are included, unless it has been greater than five years since the most recent rate case.

In each of the last three calendar years, IPL has reported earnings in excess of the authorized level for each of the four quarterly reporting periods in those years. IPL was not required to reduce its fuel cost recovery, because of its Cumulative Deficiencies. The historical periods when IPL earned less than the authorized level, which put IPL in a Cumulative Deficiency position, all relate to earnings prior to IPL’s 2018 Base Rate Order and therefore each quarter one of those under-earning periods drops out of the Cumulative Deficiency calculation. Consequently, it is likely that IPL’s Cumulative Deficiencies will drop to zero in 2020 and IPL may then be required to decrease its fuel factor if it continues to earn above the authorized level.

ECCRA

IPL may apply to the IURC for approval of a rate adjustment known as the ECCRA periodically to recover costs (including a return) to comply with certain environmental regulations applicable to IPL’s generating stations. The total amount of IPL’s equipment approved for ECCRA recovery as of December 31, 2019 was $17.4 million. The jurisdictional revenue requirement approved by the IURC to be included in IPL’s rates for the twelve-month period ending February 2020 was a net credit to customers of $28.4 million. This amount is significantly lower than prior ECCRA periods as a result of (i) having the vast majority of the ECCRA projects rolled into IPL’s basic rates and charges effective December 5, 2018 as a result of the 2018 Base Rate Order and (ii) the approximately $50 million of customer benefits being flowed through the ECCRA as a result of the 2018 Base Rate Order, as described above. The only equipment still remaining in the ECCRA as of December 31, 2019 are certain projects associated with NAAQS compliance.

DSM

Through various rate orders from the IURC, IPL has been able to recover its costs of implementing various DSM programs throughout the periods covered by this report. In 2019 and 2018, IPL also had the ability to receive performance incentives, dependent upon the level of success of the programs. Performance incentives included in revenues for the years ended December 31, 2019, 2018 and 2017 were $7.5 million, $3.8 million and $0.0 million, respectively.

On February 7, 2018, the IURC approved a settlement agreement establishing a new three year DSM plan for IPL through 2020. The approval included cost recovery of programs as well as performance incentives, depending on the level of success of the programs. The order also approved recovery of lost revenues, consistent with the provisions of the settlement agreement.

Wind and Solar Power Purchase Agreements

We are committed under a power purchase agreement to purchase all wind-generated electricity through 2029 from a wind project in Indiana. We are also committed under another agreement to purchase all wind-generated electricity through 2031 from a project in Minnesota. The Indiana project has a maximum output capacity of approximately 100 MW and the Minnesota project has a maximum output capacity of approximately 200 MW. In addition, we have 96.4 MW of solar-generated electricity in our service territory under long-term contracts (these long-term contracts have expiration dates ranging from 2021 to 2033), of which 95.9 MW was in operation as of December 31, 2019. We have authority from the IURC to recover the costs for all of these agreements through an adjustment mechanism administered within the FAC. If and when IPL sells the renewable energy attributes (in the form of renewable energy credits) generated from these facilities, the proceeds would pass back to benefit IPL’s retail customers through the FAC.

Taxes

On January 3, 2018, the IURC opened a generic investigation to review and consider the impacts from the TCJA and how any resulting benefits should be realized by customers. The IURC’s order opening this investigation directed Indiana utilities to apply regulatory accounting treatment, such as the use of regulatory assets and regulatory liabilities, for all estimated impacts resulting from the TCJA. On February 16, 2018, the IURC issued an order establishing two phases of the investigation. The first phase (“Phase I”) directed respondent utilities (including IPL) to make a filing to remove from respondents’ rates and charges for service, the impact of a lower federal income tax rate. The second phase (“Phase II”) was established to address remaining issues from the TCJA, including treatment of deferred taxes and how these benefits will be realized by customers. On August 29, 2018, the IURC approved a settlement agreement filed by IPL and various other parties to resolve the Phase I issues of the TCJA tax expense via a credit through the ECCRA rate adjustment mechanism of $9.5 million. The 2018 Base Rate Order described above resolved the Phase II and all other issues regarding the TCJA impact on IPL's rates and includes an additional credit of $14.3 million to be paid by IPL to its customers through the ECCRA rate adjustment mechanism over two years beginning in March 2019. See also Note 8, “Income Taxes - U.S. Tax Reform” for further information.

TDSIC Filing

In 2013, Senate Enrolled Act 560, the Transmission, Distribution, and Storage System Improvement Charge ("TDSIC") statute, was signed into law. The TDSIC statute was revised in 2019. Among other provisions, this legislation provides for cost recovery outside of a base rate proceeding for new or replacement electric and gas transmission, distribution, and storage projects that a public utility undertakes for the purposes of safety, reliability, system modernization, or economic development. Provisions of the TDSIC statute require that, among other things, requests for recovery include a plan of at least five years and not more than seven for eligible investments. Once the plan is approved by the IURC, eighty percent of eligible costs can be recovered using a periodic rate adjustment mechanism. The cost recovery mechanism is referred to as a TDSIC mechanism. Recoverable costs include a return on, and of, the investment, including AFUDC, post-in-service carrying charges, operation and maintenance expenses, depreciation and property taxes. The remaining twenty percent of recoverable costs are to be deferred for future recovery in the public utility’s next base rate case. The periodic rate adjustment mechanism is capped at an annual increase of no more than two percent of total retail revenues.

On July 24, 2019, IPL filed a petition with the IURC seeking approval of a seven-year TDSIC Plan for eligible transmission, distribution and storage system improvements totaling $1.2 billion from 2020 through 2027. An IURC order is expected in the first quarter of 2020. There will be no revenues and/or cost recovery until approval of the TDSIC rider, which is not expected to occur until later in 2020.

IRP Filing

In December 2019, IPL filed its IRP, which describes IPL's Preferred Resource Portfolio for meeting generation capacity needs for serving IPL's retail customers over the next several years. IPL's Preferred Resource Portfolio is IPL's reasonable least cost option and provides a cleaner and more diverse generation mix for customers. IPL's Preferred Resource Portfolio includes the retirement of 630 MW of coal-fired generation by 2023. Based on extensive modeling, IPL has determined that the cost of operating Petersburg Units 1 and 2 exceeds the value customers receive compared to alternative resources. Retirement of these units allows the company to cost-effectively diversify the portfolio and transition to lower cost and cleaner resources while maintaining a reliable system.

IPL issued an all-source Request for Proposal on December 20, 2019, in order to competitively procure replacement capacity by June 1, 2023, which is the first year IPL is expected to have a capacity shortfall. Current modeling indicates that a combination of wind, solar, storage, and energy efficiency would be the lowest reasonable cost option for the replacement capacity, but IPL will assess the type, size, and location of resources after bids are received. As a result of the decision to retire Petersburg Units 1 and 2, IPL recorded a $6.2 million obsolescence loss in December 2019 for materials and supplies inventory IPL does not believe will be utilized by the planned retirement dates, which is recorded in "Operating expenses - Operation and maintenance" on the accompanying Consolidated Statements of Operations.

Regulatory Assets and Liabilities

Regulatory assets represent deferred costs or credits that have been included as allowable costs or credits for ratemaking purposes. IPL has recorded regulatory assets or liabilities relating to certain costs or credits as authorized by the IURC or established regulatory practices in accordance with ASC 980. IPL is amortizing non tax-related regulatory assets to expense over periods ranging from 1 to 45 years. Tax-related regulatory assets represent the net income tax costs to be considered in future regulatory proceedings generally as the tax-related amounts are paid.

The amounts of regulatory assets and regulatory liabilities at December 31 are as follows:



	2019		2018		Recovery Period
	(In Thousands)
Regulatory Assets
Current:
Undercollections of rate riders	$	22,216	$	13,217	Approximately 1 year⁽¹⁾
Costs being recovered through basic rates and charges	15,182		15,182		Approximately 1 year⁽¹⁾
Total current regulatory assets	37,398		28,399
Long-term:
Unrecognized pension and other
postretirement benefit plan costs	176,646		195,559		Various⁽²⁾
Deferred MISO costs	74,660		88,052		Through 2026⁽¹⁾
Unamortized Petersburg Unit 4 carrying
charges and certain other costs	7,030		8,084		Through 2026⁽¹⁾⁽³⁾
Unamortized reacquisition premium on debt	18,330		19,714		Over remaining life of debt
Environmental projects	78,021		81,204		Through 2046⁽¹⁾⁽³⁾
Other miscellaneous	927		2,464		Various⁽⁴⁾
Total long-term regulatory assets	355,614		395,077
Total regulatory assets	$	393,012	$	423,476
Regulatory Liabilities
Current:
Overcollections and other credits being passed
to customers through rate riders	$	51,790	$	47,925	Approximately 1 year⁽¹⁾
FTRs	864		3,099		Approximately 1 year⁽¹⁾
Total current regulatory liabilities	52,654		51,024
Long-term:
ARO and accrued asset removal costs	719,680		707,662		Not applicable
Income taxes payable to customers through rates	122,156		141,058		Various
Long-term portion of credits being passed to customers
through rate riders	3,337		21,341		Through 2021
Other miscellaneous	1,257		194		To be determined
Total long-term regulatory liabilities	846,430		870,255
Total regulatory liabilities	$	899,084	$	921,279


(1)	Recovered (credited) per specific rate orders


(2)	IPL receives a return on its discretionary funding


(3)	Recovered with a current return

(4) The majority of these costs are being recovered in basic rates and charges through 2026. For the remainder, recovery is probable, but the

timing is not yet determined.

Deferred Fuel

Deferred fuel costs are a component of current regulatory assets or liabilities (which is a result of IPL charging either more or less for fuel than our actual costs to our jurisdictional customers) and are expected to be recovered through future FAC proceedings. IPL records deferred fuel in accordance with standards prescribed by the FERC. The deferred fuel adjustment is the result of variances between estimated fuel and purchased power costs in IPL’s FAC and actual fuel and purchased power costs. IPL is generally permitted to recover underestimated fuel and purchased power costs in future rates through the FAC proceedings and therefore the costs are deferred when incurred and amortized into fuel expense in the same period that IPL’s rates are adjusted to reflect these costs.

Unrecognized Pension and Postretirement Benefit Plan Costs

In accordance with ASC 715 “Compensation – Retirement Benefits” and ASC 980, we recognize a regulatory asset equal to the unrecognized actuarial gains and losses and prior service costs. Pension expenses are recorded based on the benefit plan’s actuarially determined pension liability and associated level of annual expenses to be recognized. The other postretirement benefit plan’s deferred benefit cost is the excess of the other postretirement benefit liability over the amount previously recognized.

Deferred Income Taxes Recoverable/Payable Through Rates

A deferred income tax asset or liability is created from a difference in timing of income recognition between tax laws and accounting methods. As a regulated utility, IPL includes in ratemaking the impacts of current income taxes and changes in deferred income tax liabilities or assets.

On December 22, 2017, the U.S. federal government enacted the TCJA, which, among other things, reduced the federal corporate income tax rate from 35% to 21%, beginning January 1, 2018. As required by GAAP, on December 31, 2017, IPL and IPALCO remeasured their deferred income tax assets and liabilities using the new tax rate. The impact of the reduction of the income tax rate on deferred income taxes was utilized in the 2018 Base Rate Order to reduce jurisdictional retail rates. Accordingly, we have a net regulatory deferred income tax liability of $122.2 million and $141.1 million as of December 31, 2019 and 2018, respectively.

Deferred MISO Costs

These consist of administrative costs for transmission services, transmission expansion cost sharing, and certain other operational and administrative costs from the MISO market. These costs are being recovered per specific rate order.

Environmental Costs

These consist of various costs incurred to comply with environmental regulations. These costs were approved for recovery either through IPL's ECCRA proceedings or in the 2018 Base Rate Order. Amortization periods vary, but all costs should be recovered by 2064.

ARO and Accrued Asset Removal Costs

In accordance with ASC 410 and ASC 980, IPL recognizes the amount collected in customer rates for costs of removal that do not have an associated legal retirement obligation as a deferred regulatory liability. This amount is net of the portion of legal ARO costs that is also currently being recovered in rates.

Entity Information [Line Items]

Regulatory Matters

. REGULATORY MATTERS

General

IPL is subject to regulation by the IURC as to its services and facilities, the valuation of property, the construction, purchase, or lease of electric generating facilities, the classification of accounts, rates of depreciation, retail rates and charges, the issuance of securities (other than evidences of indebtedness payable less than twelve months after the date of issue), the acquisition and sale of some public utility properties or securities and certain other matters.

In addition, IPL is subject to the jurisdiction of the FERC with respect to, among other things, short-term borrowings not regulated by the IURC, the sale of electricity at wholesale, the transmission of electric energy in interstate commerce, the classification of accounts, reliability standards, and the acquisition and sale of utility property in certain circumstances as provided by the Federal Power Act. As a regulated entity, IPL is required to use certain accounting methods prescribed by regulatory bodies which may differ from those accounting methods required to be used by unregulated entities.

IPL is also affected by the regulatory jurisdiction of the EPA at the federal level, and the IDEM at the state level. Other significant regulatory agencies affecting IPL include, but are not limited to, the NERC, the U.S. Department of Labor and the IOSHA.

Basic Rates and Charges

IPL’s basic rates and charges represent the largest component of its annual revenues. IPL’s basic rates and charges are determined after giving consideration, on a pro-forma basis, to all allowable costs for ratemaking purposes including a fair return on the fair value of the utility property used and useful in providing service to customers. These basic rates and charges are set and approved by the IURC after public hearings. Such proceedings, which have occurred at irregular intervals, involve IPL, the IURC, the Indiana Office of Utility Consumer Counselor, and other interested stakeholders. Pursuant to statute, the IURC is to conduct a periodic review of the basic rates and charges of all Indiana utilities at least once every four years, but the IURC has the authority to review the rates of any Indiana utility at any time. Once set, the basic rates and charges authorized do not assure the realization of a fair return on the fair value of property.

IPL’s declining block rate structure generally provides for residential and commercial customers to be charged a lower per kWh rate at higher consumption levels. Therefore, as volumes increase, the weighted average price per kWh decreases. Numerous factors including, but not limited to, weather, inflation, customer growth and usage, the level of actual operating and maintenance expenditures, fuel costs, generating unit availability, and capital expenditures including those required by environmental regulations can affect the return realized.

Base Rate Orders

On October 31, 2018, the IURC issued an order approving an uncontested settlement agreement previously filed with the IURC by IPL for a $43.9 million, or 3.2%, increase to annual revenues (the "2018 Base Rate Order"). The 2018 Base Rate Order includes recovery through rates of the CCGT at Eagle Valley completed in the first half of 2018, as well as other construction projects and changes to operating income since the 2016 Base Rate Order (See below). New basic rates and charges became effective on December 5, 2018. The 2018 Base Rate Order also provides customers approximately $50 million in benefits, which are flowing to customers over the two-year period that began March 2019, via the ECCRA rate adjustment mechanism. This liability, less amounts returned to IPL's

customers during 2019, is recorded primarily in "Regulatory liabilities, current" with approximately $4.7 million in "Regulatory liabilities, non-current" as of December 31, 2019 on the accompanying Consolidated Balance Sheets. In addition, the 2018 Base Rate Order provides that annual wholesale margins earned above (or below) the benchmark of $16.3 million shall be passed back (or charged) to customer rates through a rate adjustment mechanism. Similarly, the 2018 Base Rate Order provides that all capacity sales above (or below) a benchmark of $11.3 million shall be passed back (or charged) to customer rates through a rate adjustment mechanism. The 2018 Base Rate Order also approved changes to IPL's depreciation and amortization rates (including no longer deferring depreciation on the CCGT at Eagle Valley) which altogether represent a net expense increase of approximately $28.7 million annually.

In March 2016, the IURC issued the 2016 Base Rate Order authorizing IPL to increase its basic rates and charges by $30.8 million annually. IPL also received approval to implement three new rate riders for current recovery from customers of ongoing MISO costs and capacity costs, and for sharing with customers 50% of wholesale sales margins above and below the established benchmark of $6.3 million.

CCR

On April 26, 2017, the IURC approved IPL’s CCR compliance request to install a bottom ash dewatering system at its Petersburg generating station and to recover 80% of qualifying costs through a rate adjustment mechanism with the remainder recorded as a regulatory asset for recovery in a subsequent rate case. The approved capital cost of the CCR compliance plan was approximately $47 million. IPL’s bottom ash dewatering system at its Petersburg generating station went into service in September 2017.

NAAQS

On April 26, 2017, the IURC approved IPL’s request for NAAQS SO₂ compliance at its Petersburg generation station with 80% of qualifying costs recovered through a rate adjustment mechanism and the remainder recorded as a regulatory asset for recovery in a subsequent rate case. The approved capital cost of the NAAQS SO₂ compliance plan was approximately $29 million. This project went into service between August 2018 and August 2019.

Other

The DOE issued a Notice of Proposed Rule Making on September 29, 2017, which directed the FERC to exercise its authority to set just and reasonable rates that recognize the “resiliency” value provided by generation plants with certain characteristics, including having 90-days or more of on-site fuel and operating in markets where they do not receive rate base treatment through state ratemaking. Nuclear and coal-fired generation plants would have been most likely to be able to meet the requirements. As proposed, the DOE would value resiliency through rates that recover “compensable costs” that were defined to include the recovery of operating and fuel expenses, debt service and a fair return on equity. On January 8, 2018, the FERC issued an order terminating this docket stating that it failed to satisfy the legal requirements of Section 206 of the Federal Power Act of 1935. The FERC initiated a new docket to take additional steps to explore resilience issues in RTOs/ISOs. The goal of this new proceeding is to: (1) develop a common understanding among the FERC, State Commissions, RTOs/ISOs, transmission owners, and others as to what resilience of the bulk power system means and requires; (2) understand how each RTO and ISO assesses resilience in its geographic footprint; and (3) use this information to evaluate whether additional action regarding resilience is appropriate at this time. It is not possible to predict the impact of this proceeding on our business, financial condition and results of operations.

FAC and Authorized Annual Jurisdictional Net Operating Income

IPL may apply to the IURC for a change in IPL’s fuel charge every three months to recover IPL’s estimated fuel costs, including the energy portion of purchased power costs, which may be above or below the levels included in IPL’s basic rates and charges. IPL must present evidence in each FAC proceeding that it has made every reasonable effort to acquire fuel and generate or purchase power or both so as to provide electricity to its retail customers at the lowest fuel cost reasonably possible.

Independent of the IURC’s ability to review basic rates and charges, Indiana law requires electric utilities under the jurisdiction of the IURC to meet operating expense and income test requirements as a condition for approval of requested changes in the FAC. A utility may be unable to recover all of its fuel costs if its rolling twelve-month

operating income, determined at quarterly measurement dates, exceeds its authorized annual jurisdictional net operating income and there are not sufficient applicable cumulative net operating income deficiencies (“Cumulative Deficiencies”) to offset it. The Cumulative Deficiencies calculation provides that only five years’ worth of historical earnings deficiencies or surpluses are included, unless it has been greater than five years since the most recent rate case.

In each of the last three calendar years, IPL has reported earnings in excess of the authorized level for each of the four quarterly reporting periods in those years. IPL was not required to reduce its fuel cost recovery, because of its Cumulative Deficiencies. The historical periods when IPL earned less than the authorized level, which put IPL in a Cumulative Deficiency position, all relate to earnings prior to IPL’s 2018 Base Rate Order and therefore each quarter one of those underearning periods drops out of the Cumulative Deficiency calculation. Consequently, it is likely that IPL’s Cumulative Deficiencies will drop to zero in 2020 and IPL may then be required to decrease its fuel factor if it continues to earn above the authorized level.

ECCRA

IPL may apply to the IURC for approval of a rate adjustment known as the ECCRA periodically to recover costs (including a return) to comply with certain environmental regulations applicable to IPL’s generating stations. The total amount of IPL’s equipment approved for ECCRA recovery as of December 31, 2019 was $17.4 million. The jurisdictional revenue requirement approved by the IURC to be included in IPL’s rates for the twelve-month period ending February 2020 was a net credit to customers of $28.4 million. This amount is significantly lower than prior ECCRA periods as a result of (i) having the vast majority of the ECCRA projects rolled into IPL’s basic rates and charges effective December 5, 2018 as a result of the 2018 Base Rate Order and (ii) the approximately $50 million

of customer benefits being flowed through the ECCRA as a result of the 2018 Base Rate Order, as described above. The only equipment still remaining in the ECCRA as of December 31, 2019 are certain projects associated with NAAQS compliance.

DSM

Through various rate orders from the IURC, IPL has been able to recover its costs of implementing various DSM programs throughout the periods covered by this report. In 2019 and 2018, IPL also had the ability to receive performance incentives, dependent upon the level of success of the programs. Performance incentives included in revenues for the years ended December 31, 2019, 2018 and 2017 were $7.5 million, $3.8 million and $0.0 million, respectively.

On February 7, 2018, the IURC approved a settlement agreement establishing a new three year DSM plan for IPL through 2020. The approval included cost recovery of programs as well as performance incentives, depending on the level of success of the programs. The order also approved recovery of lost revenues, consistent with the provisions of the settlement agreement.

Wind and Solar Power Purchase Agreements

IPL is committed under a power purchase agreement to purchase all wind-generated electricity through 2029 from a wind project in Indiana. IPL is also committed under another agreement to purchase all wind-generated electricity through 2031 from a project in Minnesota. The Indiana project has a maximum output capacity of approximately 100 MW and the Minnesota project has a maximum output capacity of approximately 200 MW. In addition, IPL has 96.4 MW of solar-generated electricity in its service territory under long-term contracts (these long-term contracts have expiration dates ranging from 2021 to 2033), of which 95.9 MW was in operation as of December 31, 2019. IPL has authority from the IURC to recover the costs for all of these agreements through an adjustment mechanism administered within the FAC. If and when IPL sells the renewable energy attributes (in the form of renewable energy credits) generated from these facilities, the proceeds would pass back to benefit IPL’s retail customers through the FAC.

Taxes

On January 3, 2018, the IURC opened a generic investigation to review and consider the impacts from the TCJA and how any resulting benefits should be realized by customers. The IURC’s order opening this investigation directed Indiana utilities to apply regulatory accounting treatment, such as the use of regulatory assets and regulatory liabilities, for all estimated impacts resulting from the TCJA. On February 16, 2018, the IURC issued an

order establishing two phases of the investigation. The first phase (“Phase I”) directed respondent utilities (including IPL) to make a filing to remove from respondents’ rates and charges for service, the impact of a lower federal income tax rate. The second phase (“Phase II”) was established to address remaining issues from the TCJA, including treatment of deferred taxes and how these benefits will be realized by customers. On August 29, 2018, the IURC approved a settlement agreement filed by IPL and various other parties to resolve the Phase I issues of the TCJA tax expense via a credit through the ECCRA rate adjustment mechanism of $9.5 million. The 2018 Base Rate Order described above resolved the Phase II and all other issues regarding the TCJA impact on IPL's rates and includes an additional credit of $14.3 million to be paid by IPL to its customers through the ECCRA rate adjustment mechanism over two years beginning in March 2019. See also Note 8, “Income Taxes - U.S. Tax Reform” for further information.

TDSIC Filing

In 2013, Senate Enrolled Act 560, the Transmission, Distribution, and Storage System Improvement Charge ("TDSIC") statute, was signed into law. The TDSIC statute was revised in 2019. Among other provisions, this legislation provides for cost recovery outside of a base rate proceeding for new or replacement electric and gas transmission, distribution, and storage projects that a public utility undertakes for the purposes of safety, reliability, system modernization, or economic development. Provisions of the TDSIC statute require that, among other things, requests for recovery include a plan of at least five years and not more than seven for eligible investments. Once the plan is approved by the IURC, eighty percent of eligible costs can be recovered using a periodic rate adjustment mechanism. The cost recovery mechanism is referred to as a TDSIC mechanism. Recoverable costs include a return on, and of, the investment, including AFUDC, post-in-service carrying charges, operation and maintenance expenses, depreciation and property taxes. The remaining twenty percent of recoverable costs are to be deferred for future recovery in the public utility’s next base rate case. The periodic rate adjustment mechanism is capped at an annual increase of no more than two percent of total retail revenues.

On July 24, 2019, IPL filed a petition with the IURC seeking approval of a seven-year TDSIC Plan for eligible transmission, distribution and storage system improvements totaling $1.2 billion from 2020 through 2027. An IURC order is expected in the first quarter of 2020. There will be no revenues and/or cost recovery until approval of the TDSIC rider, which is not expected to occur until later in 2020.

IRP Filing

In December 2019, IPL filed its IRP, which describes IPL's Preferred Resource Portfolio for meeting generation capacity needs for serving IPL's retail customers over the next several years. IPL's Preferred Resource Portfolio is its reasonable least cost option and provides a cleaner and more diverse generation mix for customers. IPL's Preferred Resource Portfolio includes the retirement of 630 MW of coal-fired generation by 2023. Based on extensive modeling, IPL has determined that the cost of operating Petersburg Units 1 and 2 exceeds the value customers receive compared to alternative resources. Retirement of these units allows the company to cost-effectively diversify the portfolio and transition to lower cost and cleaner resources while maintaining a reliable system.

IPL issued an all-source Request for Proposal on December 20, 2019, in order to competitively procure replacement capacity by June 1, 2023, which is the first year IPL is expected to have a capacity shortfall. Current modeling indicates that a combination of wind, solar, storage, and energy efficiency would be the lowest reasonable cost option for the replacement capacity, but IPL will assess the type, size, and location of resources after bids are received. As a result of the decision to retire Petersburg Units 1 and 2, IPL recorded a $6.2 million obsolescence loss in December 2019 for materials and supplies inventory IPL does not believe will be utilized by the planned retirement dates, which is recorded in "Operating expenses - Operation and maintenance" on the accompanying Consolidated Statements of Operations.

Regulatory Assets and Liabilities

Regulatory assets represent deferred costs or credits that have been included as allowable costs or credits for ratemaking purposes. IPL has recorded regulatory assets or liabilities relating to certain costs or credits as authorized by the IURC or established regulatory practices in accordance with ASC 980. IPL is amortizing non tax-related regulatory assets to expense over periods ranging from 1 to 45 years. Tax-related regulatory assets represent the net income tax costs to be considered in future regulatory proceedings generally as the tax-related amounts are paid.

The amounts of regulatory assets and regulatory liabilities at December 31 are as follows:



	2019		2018		Recovery Period
	(In Thousands)
Regulatory Assets
Current:
Undercollections of rate riders	$	22,216	$	13,217	Approximately 1 year⁽¹⁾
Costs being recovered through basic rates and charges	15,182		15,182		Approximately 1 year⁽¹⁾
Total current regulatory assets	37,398		28,399
Long-term:
Unrecognized pension and other
postretirement benefit plan costs	176,646		195,559		Various⁽²⁾
Deferred MISO costs	74,660		88,052		Through 2026⁽¹⁾
Unamortized Petersburg Unit 4 carrying
charges and certain other costs	7,030		8,084		Through 2026⁽¹⁾⁽³⁾
Unamortized reacquisition premium on debt	18,330		19,714		Over remaining life of debt
Environmental projects	78,021		81,204		Through 2046⁽¹⁾⁽³⁾
Other miscellaneous	927		2,464		Various⁽⁴⁾
Total long-term regulatory assets	355,614		395,077
Total regulatory assets	$	393,012	$	423,476
Regulatory Liabilities
Current:
Overcollection or rate riders and other credits being passed
to customers through rate riders	$	51,790	$	47,925	Approximately 1 year⁽¹⁾
FTRs	864		3,099		Approximately 1 year⁽¹⁾
Total current regulatory liabilities	52,654		51,024
Long-term:
ARO and accrued asset removal costs	719,680		707,662		Not applicable
Deferred income taxes payable through rates	122,156		141,058		Various
Long-term portion or credits being passed to customers
through rate riders	3,337		21,341		Through 2021
Other miscellaneous	1,257		194		To be determined
Total long-term regulatory liabilities	846,430		870,255
Total regulatory liabilities	$	899,084	$	921,279


(1)	Recovered (credited) per specific rate orders


(2)	IPL receives a return on its discretionary funding


(3)	Recovered with a current return

(4) The majority of these costs are being recovered in basic rates and charges through 2026. For the remainder, recovery is probable, but the

timing is not yet determined.

Deferred Fuel

Deferred fuel costs are a component of current regulatory assets or liabilities (which is a result of IPL charging either more or less for fuel than our actual costs to our jurisdictional customers) and are expected to be recovered through future FAC proceedings. IPL records deferred fuel in accordance with standards prescribed by the FERC. The deferred fuel adjustment is the result of variances between estimated fuel and purchased power costs in IPL’s FAC and actual fuel and purchased power costs. IPL is generally permitted to recover underestimated fuel and purchased power costs in future rates through the FAC proceedings and therefore the costs are deferred when incurred and amortized into fuel expense in the same period that IPL’s rates are adjusted to reflect these costs.

Unrecognized Pension and Postretirement Benefit Plan Costs

In accordance with ASC 715 “Compensation – Retirement Benefits” and ASC 980, IPL recognizes a regulatory asset equal to the unrecognized actuarial gains and losses and prior service costs. Pension expenses are recorded based on the benefit plan’s actuarially determined pension liability and associated level of annual expenses to be recognized. The other postretirement benefit plan’s deferred benefit cost is the excess of the other postretirement benefit liability over the amount previously recognized.

Deferred Income Taxes Recoverable/Payable Through Rates

A deferred income tax asset or liability is created from a difference in timing of income recognition between tax laws and accounting methods. As a regulated utility, IPL includes in ratemaking the impacts of current income taxes and changes in deferred income tax liabilities or assets.

On December 22, 2017, the U.S. federal government enacted the TCJA, which includes a provision to, among other things, reduce the federal corporate income tax rate from 35% to 21%, beginning January 1, 2018. As required by GAAP, on December 31, 2017, IPL remeasured their deferred income tax assets and liabilities using the new tax rate. The impact of the reduction of the income tax rate on deferred income taxes will be used in future ratemaking to reduce jurisdictional retail rates. Accordingly, IPL has a net regulatory deferred income tax liability of $122.2 million and $141.1 million as of December 31, 2019 and 2018, respectively.

Deferred MISO Costs

These consist of administrative costs for transmission services, transmission expansion cost sharing, and certain other operational and administrative costs from the MISO market. These costs are being recovered per specific rate order.

Environmental Costs

These consist of various costs incurred to comply with environmental regulations. These costs were approved for recovery either through IPL's ECCRA proceedings or in the 2018 Base Rate Order. Amortization periods vary, but all costs should be recovered by 2064.

ARO and Accrued Asset Removal Costs

In accordance with ASC 410 and ASC 980, IPL recognizes the amount collected in customer rates for costs of removal that do not have an associated legal retirement obligation as a deferred regulatory liability. This amount is net of the portion of legal ARO costs that is also currently being recovered in rates.