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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549

FORM 10-Q

(Mark One)
QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended March 31, 2021

OR
TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from ________________ to ___________________

Commission
File Number
Registrant; State of Incorporation;
Address; and Telephone Number
IRS Employer
Identification No.
WEC-20210331_G1.JPG
001-09057 WEC ENERGY GROUP, INC. 39-1391525
(A Wisconsin Corporation)
231 West Michigan Street
P.O. Box 1331
Milwaukee, WI 53201
(414) 221-2345


Securities registered pursuant to Section 12(b) of the Act:
Title of Each Class Trading Symbol(s) Name of Each Exchange on Which Registered
Common Stock, $.01 Par Value WEC New York Stock Exchange

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. 

    Yes     No

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).

    Yes     No




Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of "large accelerated filer," "accelerated filer," "smaller reporting company," and "emerging growth company" in Rule 12b-2 of the Exchange Act.
Large accelerated filer Accelerated filer
Non-accelerated filer Smaller reporting company
Emerging growth company

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).

    Yes     No

Indicate the number of shares outstanding of each of the issuer's classes of common stock, as of the latest practicable date (March 31, 2021):

Common Stock, $.01 Par Value, 315,434,531 shares outstanding


Table of Contents
WEC ENERGY GROUP, INC.
QUARTERLY REPORT ON FORM 10-Q
For the Quarter Ended March 31, 2021
TABLE OF CONTENTS
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03/31/2021 Form 10-Q
i
WEC Energy Group, Inc.

Table of Contents
GLOSSARY OF TERMS AND ABBREVIATIONS

The abbreviations and terms set forth below are used throughout this report and have the meanings assigned to them below:
Subsidiaries and Affiliates
ATC American Transmission Company LLC
ATC Holdco ATC Holdco LLC
Bishop Hill III Bishop Hill Energy III LLC
Blooming Grove Blooming Grove Wind Energy Center LLC
Bluewater Bluewater Natural Gas Holding, LLC
Coyote Ridge Coyote Ridge Wind, LLC
Integrys Integrys Holding, Inc.
Jayhawk Jayhawk Wind, LLC
MERC Minnesota Energy Resources Corporation
MGU Michigan Gas Utilities Corporation
NSG North Shore Gas Company
PGL The Peoples Gas Light and Coke Company
Tatanka Ridge Tatanka Ridge Wind LLC
UMERC Upper Michigan Energy Resources Corporation
Upstream Upstream Wind Energy LLC
WE Wisconsin Electric Power Company
We Power W.E. Power, LLC
WEC Energy Group WEC Energy Group, Inc.
WECI WEC Infrastructure LLC
WG Wisconsin Gas LLC
WPS Wisconsin Public Service Corporation
Federal and State Regulatory Agencies
EPA United States Environmental Protection Agency
FERC Federal Energy Regulatory Commission
ICC Illinois Commerce Commission
IEPA Illinois Environmental Protection Agency
MPSC Michigan Public Service Commission
MPUC Minnesota Public Utilities Commission
PSCW Public Service Commission of Wisconsin
SEC United States Securities and Exchange Commission
Accounting Terms
ASU Accounting Standards Update
FASB Financial Accounting Standards Board
GAAP United States Generally Accepted Accounting Principles
LIFO Last-In, First-Out
OPEB Other Postretirement Employee Benefits
Environmental Terms
ACE Affordable Clean Energy
BATW Bottom Ash Transport Water
BTA Best Technology Available
CAA Clean Air Act
CO2
Carbon Dioxide
CSAPR Cross-State Air Pollution Rule
ELG Steam Electric Effluent Limitation Guidelines
FGD Flue Gas Desulfurization
GHG Greenhouse Gas
GMZ Groundwater Management Zone
NAAQS National Ambient Air Quality Standards
NOV Notice of Violation
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NOx Nitrogen Oxide
VN Violation Notice
Measurements
Dth Dekatherm
MW Megawatt
MWh Megawatt-hour
Other Terms and Abbreviations
2007 Junior Notes WEC Energy Group, Inc.'s 2007 Junior Subordinated Notes Due 2067
AG Attorney General
AMI Advanced Metering Infrastructure
Badger Hollow I Badger Hollow Solar Park I
Badger Hollow II Badger Hollow Solar Park II
CDC Centers for Disease Control and Prevention
CIP Conservation Improvement Program
COVID-19 Coronavirus Disease – 2019
D.C. Circuit Court of Appeals United States Court of Appeals for the District of Columbia Circuit
Executive Order 13990 Executive Order 13990 of January 20, 2021 – Protecting Public Health and the Environment and Restoring Science To Tackle the Climate Crisis
ERGS Elm Road Generating Station
ESG Progress Plan WEC Energy Group's Capital Investment Plan for Efficiency, Sustainability, and Growth for 2021-2025
Exchange Act Securities Exchange Act of 1934, as amended
FTR Financial Transmission Right
GCRM Gas Cost Recovery Mechanism
ITC Investment Tax Credit
LIBOR London Interbank Offered Rate
LNG Liquefied Natural Gas
MISO Midcontinent Independent System Operator, Inc.
OCPP Oak Creek Power Plant
OC 5 Oak Creek Power Plant Unit 5
OC 7 Oak Creek Power Plant Unit 7
OC 8 Oak Creek Power Plant Unit 8
PPA Power Purchase Agreement
PTC Production Tax Credit
QIP Qualifying Infrastructure Plant
ROE Return on Equity
SMP Natural Gas System Modernization Program
SPC COVID-19 Special Purpose Charge
SSR
System Support Resource
Tax Legislation
Tax Cuts and Jobs Act of 2017
Thunderhead
Thunderhead Wind Energy LLC
WHO World Health Organization

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING INFORMATION

In this report, we make statements concerning our expectations, beliefs, plans, objectives, goals, strategies, and future events or performance. These statements are "forward-looking statements" within the meaning of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Exchange Act. Readers are cautioned not to place undue reliance on these forward-looking statements. Forward-looking statements may be identified by reference to a future period or periods or by the use of terms such as "anticipates," "believes," "could," "estimates," "expects," "forecasts," "goals," "guidance," "intends," "may," "objectives," "plans," "possible," "potential," "projects," "seeks," "should," "targets," "will," or variations of these terms.

Forward-looking statements include, among other things, statements concerning management's expectations and projections regarding earnings, completion of capital projects, sales and customer growth, rate actions and related filings with regulatory authorities, environmental and other regulations, including associated compliance costs, legal proceedings, dividend payout ratios, effective tax rates, pension and OPEB plans, fuel costs, sources of electric energy supply, coal and natural gas deliveries, remediation costs, climate-related matters, our ESG Progress Plan, liquidity and capital resources, and other matters.

Forward-looking statements are subject to a number of risks and uncertainties that could cause our actual results to differ materially from those expressed or implied in the statements. These risks and uncertainties include those described in risk factors as set forth in our 2020 Annual Report on Form 10-K, and those identified below:

Factors affecting utility operations such as catastrophic weather-related damage, environmental incidents, unplanned facility outages and repairs and maintenance, and electric transmission or natural gas pipeline system constraints;

Factors affecting the demand for electricity and natural gas, including political or regulatory developments, varying, adverse, or unusually severe weather conditions, changes in economic conditions, customer growth and declines, commodity prices, energy conservation efforts, and continued adoption of distributed generation by customers;

The timing, resolution, and impact of rate cases and negotiations, including recovery of deferred and current costs and the ability to earn a reasonable return on investment, and other regulatory decisions impacting our regulated operations;

The impact of health pandemics, including the COVID-19 pandemic, on our business functions, financial condition, liquidity, and results of operations;

The impact of recent and future federal, state, and local legislative and/or regulatory changes, including changes in rate-setting policies or procedures, deregulation and restructuring of the electric and/or natural gas utility industries, transmission or distribution system operation, the approval process for new construction, reliability standards, pipeline integrity and safety standards, allocation of energy assistance, energy efficiency mandates, and tax laws, including those that affect our ability to use PTCs and ITCs;

Federal and state legislative and regulatory changes relating to the environment, including climate change and other environmental regulations impacting generation facilities and renewable energy standards, the enforcement of these laws and regulations, changes in the interpretation of regulations or permit conditions by regulatory agencies, and the recovery of associated remediation and compliance costs;

The ability to obtain and retain customers, including wholesale customers, due to increased competition in our electric and natural gas markets from retail choice and alternative electric suppliers, and continued industry consolidation;

The timely completion of capital projects within budgets and the ability to recover the related costs through rates;

Factors affecting the implementation of our CO2 emission and/or methane emission reduction goals, and opportunities and actions related to those goals, including related regulatory decisions, the cost of materials, supplies, and labor, technology advances, and the feasibility of competing generation projects;

The financial and operational feasibility of taking more aggressive action to further reduce GHG emissions in order to limit future global temperature increases;

The risks associated with changing commodity prices, particularly natural gas and electricity, and the availability of sources of natural gas and other fossil fuels, purchased power, materials needed to operate environmental controls at our electric
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generating facilities, or water supply due to high demand, shortages, transportation problems, nonperformance by electric energy or natural gas suppliers under existing power purchase or natural gas supply contracts, or other developments;

Changes in credit ratings, interest rates, and our ability to access the capital markets, caused by volatility in the global credit markets, our capitalization structure, and market perceptions of the utility industry, us, or any of our subsidiaries;

Changes in the method of determining LIBOR or the replacement of LIBOR with an alternative reference rate;

Costs and effects of litigation, administrative proceedings, investigations, settlements, claims, and inquiries;

The direct or indirect effect on our business resulting from terrorist attacks and cyber security intrusions, as well as the threat of such incidents, including the failure to maintain the security of personally identifiable information, the associated costs to protect our utility assets, technology systems, and personal information, and the costs to notify affected persons to mitigate their information security concerns and to comply with state notification laws;

Restrictions imposed by various financing arrangements and regulatory requirements on the ability of our subsidiaries to transfer funds to us in the form of cash dividends, loans or advances, that could prevent us from paying our common stock dividends, taxes, and other expenses, and meeting our debt obligations;

The risk of financial loss, including increases in bad debt expense, associated with the inability of our customers, counterparties, and affiliates to meet their obligations;

Changes in the creditworthiness of the counterparties with whom we have contractual arrangements, including participants in the energy trading markets and fuel suppliers and transporters;

The financial performance of ATC and its corresponding contribution to our earnings;

The investment performance of our employee benefit plan assets, as well as unanticipated changes in related actuarial assumptions, which could impact future funding requirements;

Factors affecting the employee workforce, including loss of key personnel, internal restructuring, work stoppages, and collective bargaining agreements and negotiations with union employees;

Advances in technology, and related legislation or regulation supporting the use of that technology, that result in competitive disadvantages and create the potential for impairment of existing assets;

Risks related to our non-utility renewable energy facilities, including unfavorable weather, the ability to replace expiring long-term PPAs under acceptable terms, and the availability of reliable interconnection and electricity grids;

The risk associated with the values of goodwill and other intangible assets and their possible impairment;

Potential business strategies to acquire and dispose of assets or businesses, which cannot be assured to be completed timely or within budgets, and legislative or regulatory restrictions or caps on non-utility acquisitions, investments or projects, including the State of Wisconsin's public utility holding company law;

The timing and outcome of any audits, disputes, and other proceedings related to taxes;

The ability to maintain effective internal controls in accordance with Section 404 of the Sarbanes-Oxley Act, while both continuing to integrate and consolidate our enterprise systems;

The effect of accounting pronouncements issued periodically by standard-setting bodies; and

Other considerations disclosed elsewhere herein and in other reports we file with the SEC or in other publicly disseminated written documents.

Except as may be required by law, we expressly disclaim any obligation to publicly update or revise any forward-looking statements, whether as a result of new information, future events, or otherwise.
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PART I. FINANCIAL INFORMATION

ITEM 1. FINANCIAL STATEMENTS

WEC ENERGY GROUP, INC.

CONDENSED CONSOLIDATED INCOME STATEMENTS (Unaudited) Three Months Ended
March 31
(in millions, except per share amounts) 2021 2020
Operating revenues $ 2,691.4  $ 2,108.6 
Operating expenses
Cost of sales 1,265.6  734.7 
Other operation and maintenance 479.9  455.7 
Depreciation and amortization 261.4  239.1 
Property and revenue taxes 55.2  52.5 
Total operating expenses 2,062.1  1,482.0 
Operating income 629.3  626.6 
Equity in earnings of transmission affiliates 42.6  39.8 
Other income, net 32.8  5.6 
Interest expense 119.5  129.4 
Other expense (44.1) (84.0)
Income before income taxes 585.2  542.6 
Income tax expense 74.9  90.0 
Net income 510.3  452.6 
Preferred stock dividends of subsidiary 0.3  0.3 
Net loss attributed to noncontrolling interests 0.1  0.2 
Net income attributed to common shareholders $ 510.1  $ 452.5 
Earnings per share
Basic $ 1.62  $ 1.43 
Diluted $ 1.61  $ 1.43 
Weighted average common shares outstanding
Basic 315.4 315.4
Diluted 316.2 316.7

The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these financial statements.

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WEC ENERGY GROUP, INC.

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) Three Months Ended
March 31
(in millions) 2021 2020
Net income $ 510.3  $ 452.6 
Other comprehensive income (loss), net of tax    
Derivatives accounted for as cash flow hedges    
Net derivative loss, net of tax benefit of $—, and $1.3, respectively
  (3.4)
Reclassification of realized net derivative loss to net income, net of tax 1.0  0.1 
Cash flow hedges, net 1.0  (3.3)
Defined benefit plans
Amortization of pension and OPEB costs included in net periodic benefit cost, net of tax 0.1  0.3 
Other comprehensive income (loss), net of tax 1.1  (3.0)
Comprehensive income 511.4  449.6 
Preferred stock dividends of subsidiary 0.3  0.3 
Comprehensive loss attributed to noncontrolling interests 0.1  0.2 
Comprehensive income attributed to common shareholders $ 511.2  $ 449.5 

The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these financial statements.

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WEC ENERGY GROUP, INC.

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited)
(in millions, except share and per share amounts)
March 31, 2021 December 31, 2020
Assets
Current assets
Cash and cash equivalents $ 26.1  $ 24.8 
Accounts receivable and unbilled revenues, net of reserves of $259.1 and $220.1, respectively
1,369.9  1,202.8 
Materials, supplies, and inventories 353.5  528.6 
Prepayments 258.8  263.4 
Amounts recoverable from customers 306.7  20.0 
Other 40.5  43.4 
Current assets 2,355.5  2,083.0 
Long-term assets
Property, plant, and equipment, net of accumulated depreciation and amortization of $9,481.4 and $9,364.7, respectively
25,994.4  25,707.4 
Regulatory assets 3,487.1  3,524.1 
Equity investment in transmission affiliates 1,773.6  1,764.3 
Goodwill 3,052.8  3,052.8 
Other 937.2  896.5 
Long-term assets 35,245.1  34,945.1 
Total assets $ 37,600.6  $ 37,028.1 
Liabilities and Equity
Current liabilities
Short-term debt $ 1,580.4  $ 1,776.9 
Current portion of long-term debt 787.0  785.8 
Accounts payable 656.0  880.7 
Accrued payroll and benefits 123.0  174.0 
Other 568.5  530.7 
Current liabilities 3,714.9  4,148.1 
Long-term liabilities
Long-term debt 12,317.7  11,728.1 
Deferred income taxes 4,214.1  4,059.8 
Deferred revenue, net 406.4  412.2 
Regulatory liabilities 3,890.8  3,928.1 
Environmental remediation liabilities 532.9  532.9 
Pension and OPEB obligations 319.9  327.0 
Other 1,236.3  1,229.4 
Long-term liabilities 22,918.1  22,217.5 
Commitments and contingencies (Note 20)
Common shareholders' equity
Common stock – $0.01 par value; 325,000,000 shares authorized; 315,434,531 shares outstanding
3.2  3.2 
Additional paid in capital 4,143.6  4,143.7 
Retained earnings 6,626.0  6,329.6 
Accumulated other comprehensive loss (5.7) (6.8)
Common shareholders' equity 10,767.1  10,469.7 
Preferred stock of subsidiary 30.4  30.4 
Noncontrolling interests 170.1  162.4 
Total liabilities and equity $ 37,600.6  $ 37,028.1 

The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these financial statements.
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WEC ENERGY GROUP, INC.

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) Three Months Ended
March 31
(in millions) 2021 2020
Operating activities
Net income $ 510.3  $ 452.6 
Reconciliation to cash provided by operating activities
Depreciation and amortization 261.4  239.1 
Deferred income taxes and ITCs, net 129.6  92.1 
Contributions and payments related to pension and OPEB plans (4.1) (3.7)
Equity income in transmission affiliates, net of distributions (9.2) 0.8 
Change in –
Accounts receivable and unbilled revenues, net (150.4) (3.5)
Materials, supplies, and inventories 175.1  158.7 
Amounts recoverable from customers (286.7) 8.1 
Other current assets 20.2  57.3 
Accounts payable (181.5) (250.1)
Other current liabilities (2.3) (27.7)
Other, net (67.2) (33.2)
Net cash provided by operating activities 395.2  690.5 
Investing activities
Capital expenditures (470.6) (496.1)
Acquisition of Jayhawk (119.4) — 
Capital contributions to transmission affiliates   (3.0)
Proceeds from the sale of assets 11.3  1.3 
Proceeds from the sale of investments held in rabbi trust 12.7  17.0 
Other, net 24.7  17.8 
Net cash used in investing activities (541.3) (463.0)
Financing activities
Exercise of stock options 1.2  16.0 
Purchase of common stock (6.6) (40.4)
Dividends paid on common stock (213.7) (199.5)
Issuance of long-term debt 600.0  — 
Retirement of long-term debt (14.7) (14.0)
Issuance of short-term loan   340.0 
Repayment of short-term loan (340.0) — 
Change in other short-term debt 143.5  (343.6)
Other, net (6.6) (2.6)
Net cash provided by (used in) financing activities 163.1  (244.1)
Net change in cash, cash equivalents, and restricted cash 17.0  (16.6)
Cash, cash equivalents, and restricted cash at beginning of period 72.6  82.3 
Cash, cash equivalents, and restricted cash at end of period $ 89.6  $ 65.7 

The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these financial statements.

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WEC ENERGY GROUP, INC.

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY (Unaudited)
WEC Energy Group Common Shareholders' Equity
(in millions, except per share amounts) Common Stock Additional Paid In Capital Retained Earnings Accumulated Other Comprehensive Loss Total Common Shareholders' Equity Preferred Stock of Subsidiary Non-controlling Interests Total Equity
Balance at December 31, 2020 $ 3.2  $ 4,143.7  $ 6,329.6  $ (6.8) $ 10,469.7  $ 30.4  $ 162.4  $ 10,662.5 
Net income attributed to common shareholders     510.1    510.1      510.1 
Net loss attributed to noncontrolling interests             (0.1) (0.1)
Other comprehensive income       1.1  1.1      1.1 
Common stock dividends of $0.6775 per share
    (213.7)   (213.7)     (213.7)
Exercise of stock options   1.2      1.2      1.2 
Purchase of common stock   (6.6)     (6.6)     (6.6)
Acquisition of a noncontrolling interest             6.2  6.2 
Capital contributions from noncontrolling interest             2.0  2.0 
Distributions to noncontrolling interests             (0.4) (0.4)
Stock-based compensation and other   5.3      5.3      5.3 
Balance at March 31, 2021 $ 3.2  $ 4,143.6  $ 6,626.0  $ (5.7) $ 10,767.1  $ 30.4  $ 170.1  $ 10,967.6 

WEC Energy Group Common Shareholders' Equity
(in millions, except per share amounts) Common Stock Additional Paid In Capital Retained Earnings Accumulated Other Comprehensive Loss Total Common Shareholders' Equity Preferred Stock of Subsidiary Non-controlling Interests Total Equity
Balance at December 31, 2019 $ 3.2  $ 4,186.6  $ 5,927.7  $ (4.1) $ 10,113.4  $ 30.4  $ 110.8  $ 10,254.6 
Net income attributed to common shareholders —  —  452.5  —  452.5  —  —  452.5 
Net loss attributed to noncontrolling interests —  —  —  —  —  —  (0.2) (0.2)
Other comprehensive loss —  —  —  (3.0) (3.0) —  —  (3.0)
Common stock dividends of $0.6325 per share
—  —  (199.5) —  (199.5) —  —  (199.5)
Exercise of stock options —  16.0  —  —  16.0  —  —  16.0 
Purchase of common stock —  (40.4) —  —  (40.4) —  —  (40.4)
Distributions to noncontrolling interests —  —  —  —  —  —  (0.5) (0.5)
Stock-based compensation and other —  5.1  —  —  5.1  —  —  5.1 
Balance at March 31, 2020 $ 3.2  $ 4,167.3  $ 6,180.7  $ (7.1) $ 10,344.1  $ 30.4  $ 110.1  $ 10,484.6 

The accompanying Notes to Condensed Consolidated Financial Statements are an integral part of these financial statements.

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WEC ENERGY GROUP, INC.
NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited)
March 31, 2021

NOTE 1—GENERAL INFORMATION

WEC Energy Group serves approximately 1.6 million electric customers and 3.0 million natural gas customers, owns approximately 60% of ATC, and owns majority interests in multiple wind generating facilities as part of its non-utility energy infrastructure business.

As used in these notes, the term "financial statements" refers to the condensed consolidated financial statements. This includes the income statements, statements of comprehensive income, balance sheets, statements of cash flows, and statements of equity, unless otherwise noted. In this report, when we refer to "the Company," "us," "we," "our," or "ours," we are referring to WEC Energy Group and all of its subsidiaries.

On our financial statements, we consolidate our majority-owned subsidiaries which we control and reflect noncontrolling interests for the portion of entities that we do not own as a component of consolidated equity separate from the equity attributable to our shareholders. The noncontrolling interests that we reported as equity on our balance sheets related to the minority interests at Bishop Hill III, Blooming Grove, Coyote Ridge, Jayhawk, Tatanka Ridge, and Upstream held by third parties.

We use the equity method to account for investments in companies we do not control but over which we exercise significant influence regarding their operating and financial policies. As a result of our limited voting rights, we account for ATC and ATC Holdco as equity method investments. See Note 17, Investment in Transmission Affiliates, for more information.

We have prepared the unaudited interim financial statements presented in this Form 10-Q pursuant to the rules and regulations of the SEC and GAAP. Accordingly, these financial statements do not include all of the information and footnotes required by GAAP for annual financial statements. These financial statements should be read in conjunction with the consolidated financial statements and footnotes in our Annual Report on Form 10-K for the year ended December 31, 2020. Financial results for an interim period may not give a true indication of results for the year. In particular, the results of operations for the three months ended March 31, 2021, are not necessarily indicative of expected results for 2021 due to seasonal variations and other factors, including any continuing financial impacts from the COVID-19 pandemic.

In management's opinion, we have included all adjustments, normal and recurring in nature, necessary for a fair presentation of our financial results.

NOTE 2—ACQUISITIONS

The purchase price of certain acquisitions below includes intangibles recorded as long-term liabilities related to PPAs and interconnection agreements. See Note 16, Goodwill and Intangibles, for more information.

Acquisition of a Wind Energy Generation Facility in Kansas

In February 2021, WECI completed the acquisition of a 90% ownership interest in Jayhawk, a 190 MW wind generating facility under construction in Bourbon and Crawford counties, Kansas, for $119.4 million, which included transaction costs, and was allocated primarily to property, plant, and equipment. In March 2021, WECI incurred an additional $37.9 million of capital expenditures for the project for a total investment of $157.3 million. Upon completion, we expect WECI's total investment to be approximately $302 million. The project has an offtake agreement with an unaffiliated third party for all of the energy to be produced by the facility for a period of 10 years. Under the Tax Legislation, WECI's investment in Jayhawk is expected to qualify for PTCs. WECI is entitled to 99% of the tax benefits related to this facility for the first 10 years of commercial operation, after which we will be entitled to tax benefits equal to our ownership interest. Commercial operation is expected to begin by the end of 2021. Jayhawk is included in the non-utility energy infrastructure segment.

Acquisition of a Wind Energy Generation Facility in South Dakota

In December 2020, WECI completed the acquisition of an 85% ownership interest in Tatanka Ridge, a 155 MW wind generating facility in Deuel County, South Dakota that became commercially operational in January 2021. WECI's total investment was $240.1 million, which included transaction costs. Tatanka Ridge has offtake agreements for all the energy produced with an affiliate
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of an investment grade multinational company for 12 years and a well-established electric cooperative that serves utilities in multiple states for 10 years. Under the Tax Legislation, WECI's investment in Tatanka Ridge qualifies for PTCs. WECI is entitled to 99% of the tax benefits related to this facility for the first 11 years of commercial operation, after which we will be entitled to tax benefits equal to our ownership interest. Tatanka Ridge is included in the non-utility energy infrastructure segment.

Acquisition of Wind Generation Facilities in Nebraska

In August 2019, WECI signed an agreement to acquire an 80% ownership interest in Thunderhead, a 300 MW wind generating facility under construction in Antelope and Wheeler counties in Nebraska, for a total investment of approximately $338 million. In February 2020, WECI agreed to acquire an additional 10% ownership interest in Thunderhead for $43 million. The project has an offtake agreement with an unaffiliated third party for all of the energy to be produced by the facility for 12 years. Under the Tax Legislation, WECI's investment in Thunderhead is expected to qualify for PTCs. The transaction was approved by FERC in April 2020, and commercial operation was initially expected to begin by the end of 2020. However, due to a delay in construction of the required substation, Thunderhead is now expected to begin commercial operation by the end of 2021. The transaction is expected to close upon commercial operation. Thunderhead will be included in the non-utility energy infrastructure segment.

NOTE 3—OPERATING REVENUES

For more information about our operating revenues, see Note 1(d), Operating Revenues, in our 2020 Annual Report on Form 10-K.

Disaggregation of Operating Revenues

The following tables present our operating revenues disaggregated by revenue source. We do not have any revenues associated with our electric transmission segment, which includes investments accounted for using the equity method. We disaggregate revenues into categories that depict how the nature, amount, timing, and uncertainty of revenues and cash flows are affected by economic factors. For our segments, revenues are further disaggregated by electric and natural gas operations and then by customer class. Each customer class within our electric and natural gas operations have different expectations of service, energy and demand requirements, and can be impacted differently by regulatory activities within their jurisdictions.
(in millions) Wisconsin Illinois Other States Total Utility
Operations
Non-Utility Energy Infrastructure Corporate
and Other
Reconciling
Eliminations
WEC Energy Group Consolidated
Three Months Ended March 31, 2021            
Electric $ 1,095.0  $   $   $ 1,095.0  $   $   $   $ 1,095.0 
Natural gas 627.3  693.5  225.6  1,546.4  14.6    (13.3) 1,547.7 
Total regulated revenues 1,722.3  693.5  225.6  2,641.4  14.6    (13.3) 2,642.7 
Other non-utility revenues     4.7  4.7  23.2    (1.6) 26.3 
Total revenues from contracts with customers 1,722.3  693.5  230.3  2,646.1  37.8    (14.9) 2,669.0 
Other operating revenues 9.4  9.9  3.0  22.3  99.8  0.1  (99.8)
(1)
22.4 
Total operating revenues $ 1,731.7  $ 703.4  $ 233.3  $ 2,668.4  $ 137.6  $ 0.1  $ (114.7) $ 2,691.4 

(in millions) Wisconsin Illinois Other States Total Utility
Operations
Non-Utility Energy Infrastructure Corporate
and Other
Reconciling
Eliminations
WEC Energy Group Consolidated
Three Months Ended March 31, 2020            
Electric $ 1,034.6  $ —  $ —  $ 1,034.6  $ —  $ —  $ —  $ 1,034.6 
Natural gas 458.9  433.6  139.8  1,032.3  14.5  —  (14.1) 1,032.7 
Total regulated revenues 1,493.5  433.6  139.8  2,066.9  14.5  —  (14.1) 2,067.3 
Other non-utility revenues —  —  4.4  4.4  16.4  0.4  (1.6) 19.6 
Total revenues from contracts with customers 1,493.5  433.6  144.2  2,071.3  30.9  0.4  (15.7) 2,086.9 
Other operating revenues 5.4  14.0  2.2  21.6  98.7  0.1  (98.7)
(1)
21.7 
Total operating revenues $ 1,498.9  $ 447.6  $ 146.4  $ 2,092.9  $ 129.6  $ 0.5  $ (114.4) $ 2,108.6 

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(1)Amounts eliminated represent lease revenues related to certain plants that We Power leases to WE to supply electricity to its customers. Lease payments are billed from We Power to WE and then recovered in WE's rates as authorized by the PSCW and the FERC. WE operates the plants and is authorized by the PSCW and state law to fully recover prudently incurred operating and maintenance costs in electric rates.

Revenues from Contracts with Customers

Electric Utility Operating Revenues

The following table disaggregates electric utility operating revenues into customer class:
Electric Utility Operating Revenues
Three Months Ended March 31
(in millions) 2021 2020
Residential $ 423.7  $ 404.9 
Small commercial and industrial 331.4  323.6 
Large commercial and industrial 209.5  194.6 
Other 7.8  7.3 
Total retail revenues 972.4  930.4 
Wholesale 39.7  42.1 
Resale 62.7  45.2 
Steam 14.8  8.4 
Other utility revenues 5.4  8.5 
Total electric utility operating revenues $ 1,095.0  $ 1,034.6 

Natural Gas Utility Operating Revenues

The following tables disaggregate natural gas utility operating revenues into customer class:
(in millions) Wisconsin Illinois Other States Total Natural Gas Utility Operating Revenues
Three Months Ended March 31, 2021      
Residential $ 347.6  $ 333.9  $ 87.9  $ 769.4 
Commercial and industrial 176.4  102.7  43.9  323.0 
Total retail revenues 524.0  436.6  131.8  1,092.4 
Transport 24.4  74.2  11.0  109.6 
Other utility revenues (1)
78.9  182.7  82.8  344.4 
Total natural gas utility operating revenues $ 627.3  $ 693.5  $ 225.6  $ 1,546.4 

(in millions) Wisconsin Illinois Other States Total Natural Gas Utility Operating Revenues
Three Months Ended March 31, 2020      
Residential $ 313.1  $ 282.9  $ 95.3  $ 691.3 
Commercial and industrial 151.3  91.4  51.7  294.4 
Total retail revenues 464.4  374.3  147.0  985.7 
Transport 24.1  72.7  10.5  107.3 
Other utility revenues (1)
(29.6) (13.4) (17.7) (60.7)
Total natural gas utility operating revenues $ 458.9  $ 433.6  $ 139.8  $ 1,032.3 

(1)Includes revenues subject to collection from (refund to) customers for purchased gas adjustment costs.

Other Natural Gas Operating Revenues

We have other natural gas operating revenues from Bluewater, which is in our non-utility energy infrastructure segment. Bluewater has entered into long-term service agreements for natural gas storage services with WE, WPS, and WG, and also provides limited service to unaffiliated customers. All amounts associated with the service agreements with WE, WPS, and WG have been eliminated at the consolidated level.
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Other Non-Utility Operating Revenues

Other non-utility operating revenues consist primarily of the following:
Three Months Ended March 31
(in millions) 2021 2020
Wind generation revenues $ 15.8  $ 9.3 
We Power revenues (1)
5.8  5.5 
Appliance service revenues 4.7  4.4 
Distributed renewable solar project revenues   0.4 
Total other non-utility operating revenues $ 26.3  $ 19.6 

(1)As part of the construction of the We Power electric generating units, we capitalized interest during construction, which is included in property, plant, and equipment. As allowed by the PSCW, we collected these carrying costs from WE's utility customers during construction. The equity portion of these carrying costs was recorded as a contract liability, and we continually amortize the deferred carrying costs to revenues over the related lease term that We Power has with WE. During the three months ended March 31, 2021 and 2020, we recorded $5.8 million and $5.5 million, respectively, of revenues related to these deferred carrying costs. These contract liabilities are presented as deferred revenue, net on our balance sheets.

Other Operating Revenues

Other operating revenues consist primarily of the following:
Three Months Ended March 31
(in millions) 2021 2020
Late payment charges $ 15.0  $ 12.1 
Alternative revenues 6.2  8.5 
Other 1.2  1.1 
Total other operating revenues $ 22.4  $ 21.7 

NOTE 4—CREDIT LOSSES

Our exposure to credit losses is related to our accounts receivable and unbilled revenue balances, which are primarily generated from the sale of electricity and natural gas by our regulated utility operations. Credit losses associated with our utility operations are analyzed at the reportable segment level as we believe contract terms, political and economic risks, and the regulatory environment are similar at this level as our reportable segments are generally based on the geographic location of the underlying utility operations.

We have an accounts receivable and unbilled revenue balance associated with our non-utility energy infrastructure segment, related to the sale of electricity from our majority-owned wind generating facilities through agreements with several large high credit quality counterparties.

We evaluate the collectability of our accounts receivable and unbilled revenue balances considering a combination of factors. For some of our larger customers and also in circumstances where we become aware of a specific customer's inability to meet its financial obligations to us, we record a specific allowance for credit losses against amounts due in order to reduce the net recognized receivable to the amount we reasonably believe will be collected. For all other customers, we use the accounts receivable aging method to calculate an allowance for credit losses. Using this method, we classify accounts receivable into different aging buckets and calculate a reserve percentage for each aging bucket based upon historical loss rates. The calculated reserve percentages are updated on at least an annual basis, in order to ensure recent macroeconomic, political, and regulatory trends are captured in the calculation, to the extent possible. Risks identified that we do not believe are reflected in the calculated reserve percentages, are assessed on a quarterly basis to determine whether further adjustments are required.

We monitor our ongoing credit exposure through active review of counterparty accounts receivable balances against contract terms and due dates. Our activities include timely account reconciliation, dispute resolution and payment confirmation. To the extent possible, we work with customers with past due balances to negotiate payment plans, but will disconnect customers for non-payment as allowed by our regulators, if necessary, and employ collection agencies and legal counsel to pursue recovery of defaulted receivables. For our larger customers, detailed credit review procedures may be performed in advance of any sales being
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made. We sometimes require letters of credit, parental guarantees, prepayments or other forms of credit assurance from our larger customers to mitigate credit risk. See Note 22, Regulatory Environment, for information on certain regulatory actions that were and/or are being taken for the purpose of ensuring that essential utility services are available to our customers during the COVID-19 pandemic.

We have included tables below that show our gross third-party receivable balances and the related allowance for credit losses at March 31, 2021 and December 31, 2020, by reportable segment.
(in millions) Wisconsin Illinois Other States Total Utility
Operations
Non-Utility Energy Infrastructure Corporate
and Other
WEC Energy Group Consolidated
March 31, 2021
Accounts receivable and unbilled revenues $ 1,056.9  $ 465.8  $ 77.5  $ 1,600.2  $ 24.9  $ 3.9  $ 1,629.0 
Allowance for credit losses 129.5  122.0  7.6  259.1      259.1 
Accounts receivable and unbilled revenues, net (1)
$ 927.4  $ 343.8  $ 69.9  $ 1,341.1  $ 24.9  $ 3.9  $ 1,369.9 
Total accounts receivable, net – past due greater than 90 days (1)
$ 68.8  $ 38.4  $ 3.8  $ 111.0  $   $   $ 111.0 
Past due greater than 90 days – collection risk mitigated by regulatory mechanisms (1)
97.5  % 100.0  %   % 95.0  %   %   % 95.0  %

(in millions) Wisconsin Illinois Other States Total Utility
Operations
Non-Utility Energy Infrastructure Corporate
and Other
WEC Energy Group Consolidated
December 31, 2020
Accounts receivable and unbilled revenues $ 899.8  $ 393.9  $ 79.8  $ 1,373.5  $ 45.0  $ 4.4  $ 1,422.9 
Allowance for credit losses 102.1  111.6  6.4  220.1  —  —  220.1 
Accounts receivable and unbilled revenues, net (1)
$ 797.7  $ 282.3  $ 73.4  $ 1,153.4  $ 45.0  $ 4.4  $ 1,202.8 
Total accounts receivable, net – past due greater than 90 days (1)
$ 84.8  $ 34.5  $ 3.5  $ 122.8  $ —  $ —  $ 122.8 
Past due greater than 90 days – collection risk mitigated by regulatory mechanisms (1)
97.6  % 100.0  % —  % 95.5  % —  % —  % 95.5  %

(1)Our exposure to credit losses for certain regulated utility customers is mitigated by regulatory mechanisms we have in place. Specifically, rates related to all of the customers in our Illinois segment, as well as the residential rates of WE, WPS, and WG in our Wisconsin segment, include riders or other mechanisms for cost recovery or refund of uncollectible expense based on the difference between the actual provision for credit losses and the amounts recovered in rates. As a result, at March 31, 2021, $742.0 million, or 54.2%, of our net accounts receivable and unbilled revenues balance had regulatory protections in place to mitigate the exposure to credit losses. In addition, we have received specific orders related to the deferral of certain costs (including credit losses) incurred as a result of the COVID-19 pandemic. The additional protections related to our accounts receivable and unbilled revenue balances provided by these orders are subject to prudency reviews and are still being assessed. They are not reflected in the percentages in the above table or this note. See Note 22, Regulatory Environment, for more information on these orders.

A rollforward of the allowance for credit losses by reportable segment for the three months ended March 31, 2021 and 2020 is included below:
(in millions) Wisconsin Illinois Other States Total Utility
Operations
Corporate
and Other
WEC Energy Group Consolidated
Balance at December 31, 2020 $ 102.1  $ 111.6  $ 6.4  $ 220.1  $ —  $ 220.1 
Provision for credit losses 13.7  7.1  1.3  22.1    22.1 
Provision for credit losses deferred for future recovery or refund 22.3  3.1    25.4    25.4 
Write-offs charged against the allowance (18.5) (2.8) (0.5) (21.8)   (21.8)
Recoveries of amounts previously written off 9.9  3.0  0.4  13.3    13.3 
Balance at March 31, 2021 $ 129.5  $ 122.0  $ 7.6  $ 259.1  $   $ 259.1 

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The increase in the allowance for credit losses at March 31, 2021, compared to December 31, 2020, was driven by higher past due accounts receivable balances at our utility segments, primarily related to residential customers. This increase in accounts receivable balances in arrears was driven by the continued economic disruptions caused by the COVID-19 pandemic, including continued high unemployment rates. Also, as a result of the winter moratorium rules, which are discussed in more detail below, and the COVID-19 pandemic and related regulatory orders we have received, we have been unable to disconnect any of our Wisconsin and Illinois residential customers since the fourth quarter of 2019. See Note 22, Regulatory Environment, for more information.
(in millions) Wisconsin Illinois Other States Total Utility
Operations
Corporate
and Other
WEC Energy Group Consolidated
Balance at December 31, 2019 $ 59.9  $ 75.9  $ 4.1  $ 139.9  $ 0.1  $ 140.0 
Provision for credit losses 13.7  14.4  0.7  28.8  —  28.8 
Provision for credit losses deferred for future recovery or refund 3.3  29.5  —  32.8  —  32.8 
Write-offs charged against the allowance (19.7) (31.6) (1.3) (52.6) —  (52.6)
Recoveries of amounts previously written off 10.5  4.9  0.4  15.8  —  15.8 
Balance at March 31, 2020 $ 67.7  $ 93.1  $ 3.9  $ 164.7  $ 0.1  $ 164.8 

The increase in the allowance for credit losses at our Wisconsin and Illinois reportable segments was driven by an increase in past due accounts receivable balances from December 31, 2019 to March 31, 2020. This is a trend we generally see over the winter moratorium months, when we are not allowed to disconnect customer service as a result of non-payment. In Wisconsin, the winter moratorium begins on November 1 and ends on April 15, and in Illinois the winter moratorium begins on December 1 and ends on March 31.

NOTE 5—REGULATORY ASSETS AND LIABILITIES

The following regulatory assets and liabilities were reflected on our balance sheets at March 31, 2021 and December 31, 2020. For more information on our regulatory assets and liabilities, see Note 6, Regulatory Assets and Liabilities, in our 2020 Annual Report on Form 10-K.
(in millions) March 31, 2021 December 31, 2020
Regulatory assets
Pension and OPEB costs $ 1,073.9  $ 1,101.6 
Plant retirements 733.1  740.8 
Environmental remediation costs 623.1  638.2 
Income tax related items 459.3  454.6 
Energy costs recoverable through rate adjustments (1)
301.6  1.1 
Asset retirement obligations 186.0  181.3 
SSR 134.6  135.6 
Securitization 106.9  105.2 
Uncollectible expense 73.0  82.0 
Derivatives 9.6  26.5 
Other, net 92.7  77.2 
Total regulatory assets $ 3,793.8  $ 3,544.1 
Balance sheet presentation
Amounts recoverable from customers (1)
$ 306.7  $ 20.0 
Regulatory assets 3,487.1  3,524.1 
Total regulatory assets $ 3,793.8  $ 3,544.1 

(1)The increase in these regulatory assets primarily relates to the high natural gas costs that were incurred as a result of the extreme winter weather conditions in February 2021. See Note 22, Regulatory Environment, for more information.
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(in millions) March 31, 2021 December 31, 2020
Regulatory liabilities
Income tax related items $ 2,111.0  $ 2,137.7 
Removal costs 1,234.6  1,221.1 
Pension and OPEB benefits 373.1  378.1 
Electric transmission costs 75.9  78.5 
Earnings sharing mechanisms 30.8  36.9 
Energy costs refundable through rate adjustments 24.7  59.9 
Derivatives 17.4  16.4 
Energy efficiency programs 11.0  9.9 
Uncollectible expense 3.2  25.5 
Other, net 21.6  15.1 
Total regulatory liabilities $ 3,903.3  $ 3,979.1 
Balance sheet presentation
Other current liabilities $ 12.5  $ 51.0 
Regulatory liabilities 3,890.8  3,928.1 
Total regulatory liabilities $ 3,903.3  $ 3,979.1 

NOTE 6—PROPERTY, PLANT, AND EQUIPMENT

During a significant rain event in May 2020, an underground steam tunnel in downtown Milwaukee flooded and steam vented into WE’s Public Service Building. The damage to the building from the flooding and steam was extensive and will require significant repairs and restorations. As of March 31, 2021, WE had incurred $49.3 million of costs related to these repairs and restorations. WE received $20.0 million of insurance proceeds in 2020 to cover a portion of these costs and $16.8 million was recorded as a receivable for future insurance recoveries as of March 31, 2021. The remaining $12.5 million of costs were included in other operation and maintenance expense in 2020. We anticipate that the majority of future capital expenditures required to restore the Public Service Building will either be covered by insurance or recovery will be requested from the PSCW. As such, we do not currently expect a significant impact to our future results of operations, and although we may experience differences between periods in the timing of cash flows, we also do not currently expect a significant impact to our long-term cash flows from this event.

NOTE 7—COMMON EQUITY

Stock-Based Compensation

During the three months ended March 31, 2021, the Compensation Committee of our Board of Directors awarded the following stock-based compensation awards to our directors, officers, and certain other key employees:
Award Type Number of Awards
Stock options (1)
530,612 
Restricted shares (2)
69,681 
Performance units 152,382 

(1)Stock options awarded had a weighted-average exercise price of $91.06 and a weighted-average grant date fair value of $13.20 per option.

(2)Restricted shares awarded had a weighted-average grant date fair value of $91.06 per share.

Restrictions

Our ability as a holding company to pay common stock dividends primarily depends on the availability of funds received from our utility subsidiaries; We Power; Bluewater Gas Storage, LLC; ATC Holding LLC, which holds our ownership interest in ATC; and WECI. Various financing arrangements and regulatory requirements impose certain restrictions on the ability of our subsidiaries to transfer funds to us in the form of cash dividends, loans, or advances. All of our utility subsidiaries, with the exception of UMERC and MGU, are prohibited from loaning funds to us, either directly or indirectly. See Note 11, Common Equity, in our 2020 Annual Report on Form 10-K for additional information on these and other restrictions.

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We do not believe that these restrictions will materially affect our operations or limit any dividend payments in the foreseeable future.

Common Stock Dividends

On April 15, 2021, our Board of Directors declared a quarterly cash dividend of $0.6775 per share, payable on June 1, 2021, to shareholders of record on May 14, 2021.

NOTE 8—SHORT-TERM DEBT AND LINES OF CREDIT

The following table shows our short-term borrowings and their corresponding weighted-average interest rates:
(in millions, except percentages) March 31, 2021 December 31, 2020
Commercial paper
Amount outstanding $ 1,580.4  $ 1,436.9 
Weighted-average interest rate on amounts outstanding 0.19  % 0.21  %
Term loan
Amount outstanding $   $ 340.0 
Weighted-average interest rate on amounts outstanding n/a 0.99  %

Our average amount of commercial paper borrowings based on daily outstanding balances during the three months ended March 31, 2021 was $1,445.3 million with a weighted-average interest rate during the period of 0.18%.

In order to enhance our liquidity position in response to the COVID-19 pandemic, in March 2020, WEC Energy Group entered into a $340.0 million 364-day term loan. The weighted-average interest rate on the term loan during the three months ended March 31, 2021 was 0.99%. In March 2021, we repaid the term loan using the net proceeds from the issuance of our 0.80% Senior Notes. See Note 9, Long-Term Debt, for more information.

The information in the table below relates to our revolving credit facilities used to support our commercial paper borrowing programs, including remaining available capacity under these facilities:
(in millions) Maturity March 31, 2021
WEC Energy Group October 2022 1,200.0 
WE October 2022 500.0 
WPS October 2022 400.0 
WG October 2022 350.0 
PGL October 2022 350.0 
Total short-term credit capacity $ 2,800.0 
Less:  
Letters of credit issued inside credit facilities $ 2.3 
Commercial paper outstanding 1,580.4 
Available capacity under existing agreements $ 1,217.3 

NOTE 9—LONG-TERM DEBT

WEC Energy Group, Inc.

In March 2021, we issued $600.0 million of 0.80% Senior Notes due March 15, 2024, and used the net proceeds to repay the $340.0 million 364-day term loan entered into in March 2020 and for general corporate purposes.

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NOTE 10—MATERIALS, SUPPLIES, AND INVENTORIES

Our inventory consisted of:
(in millions) March 31, 2021 December 31, 2020
Materials and supplies $ 218.3  $ 218.1 
Natural gas in storage 68.3  224.9 
Fossil fuel 66.9  85.6 
Total $ 353.5  $ 528.6 

PGL and NSG price natural gas storage injections at the calendar year average of the costs of natural gas supply purchased. Withdrawals from storage are priced on the LIFO cost method. For interim periods, the difference between current projected replacement cost and the LIFO cost for quantities of natural gas temporarily withdrawn from storage is recorded as a temporary LIFO liquidation debit or credit. At March 31, 2021, we had a temporary LIFO liquidation credit of $66.3 million recorded within other current liabilities on our balance sheet. Due to seasonality requirements, PGL and NSG expect these interim reductions in LIFO layers to be replenished by year end.

Substantially all other materials and supplies, natural gas in storage, and fossil fuel inventories are recorded using the weighted-average cost method of accounting.

NOTE 11—INCOME TAXES

The provision for income taxes differs from the amount of income tax determined by applying the applicable United States statutory federal income tax rate to income before income taxes as a result of the following:
Three Months Ended March 31, 2021 Three Months Ended March 31, 2020
(in millions) Amount Effective Tax Rate Amount Effective Tax Rate
Statutory federal income tax $ 122.8  21.0  % $ 113.9  21.0  %
State income taxes net of federal tax benefit 36.9  6.3  % 34.0  6.3  %
PTCs (34.0) (5.8) % (18.4) (3.4) %
Federal excess deferred tax amortization – Wisconsin unprotected (30.3) (5.2) % (22.1) (4.1) %
Federal excess deferred tax amortization (14.6) (2.5) % (13.0) (2.4) %
Uncertain tax positions (8.2) (1.4) % —  —  %
Other 2.3  0.4  % (4.4) (0.8) %
Total income tax expense $ 74.9  12.8  % $ 90.0  16.6  %

The effective tax rates of 12.8% and 16.6% for the three months ended March 31, 2021 and 2020, respectively, differ from the United States statutory federal income tax rate of 21%, primarily due to PTCs generated from ownership interests in wind generation facilities in our non-utility energy infrastructure segment and the recognition of certain unprotected deferred tax benefits created as a result of the Tax Legislation. In accordance with the rate order received from the PSCW in December 2019, our Wisconsin utilities are amortizing the unprotected deferred tax benefits over periods ranging from two years to four years, to reduce near-term rate impacts to their customers. In addition, the impact of the protected benefits associated with the Tax Legislation, as discussed in more detail below, drove a decrease in the effective tax rate, which was partially offset by state income taxes.

The Tax Legislation required our regulated utilities to remeasure their deferred income taxes and we began to amortize the resulting excess protected deferred income taxes beginning in 2018 in accordance with normalization requirements (see federal excess deferred tax amortization line above).

See Note 22, Regulatory Environment, for more information on unprotected tax credits.

NOTE 12—FAIR VALUE MEASUREMENTS

Fair value is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price).

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Fair value accounting rules provide a fair value hierarchy that prioritizes the inputs used to measure fair value. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority to unobservable inputs (Level 3 measurement). The three levels of the fair value hierarchy are defined as follows:

Level 1 – Quoted prices are available in active markets for identical assets or liabilities as of the reporting date. Active markets are those in which transactions for the asset or liability occur in sufficient frequency and volume to provide pricing information on an ongoing basis.

Level 2 – Pricing inputs are observable, either directly or indirectly, but are not quoted prices included within Level 1. Level 2 includes those financial instruments that are valued using external inputs within models or other valuation methods.

Level 3 – Pricing inputs include significant inputs that are generally less observable from objective sources. These inputs may be used with internally developed methods that result in management's best estimate of fair value. Level 3 instruments include those that may be more structured or otherwise tailored to customers' needs.

Assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. We use a mid-market pricing convention (the mid-point price between bid and ask prices) as a practical measure for valuing certain derivative assets and liabilities. We primarily use a market approach for recurring fair value measurements and attempt to use valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs.

When possible, we base the valuations of our derivative assets and liabilities on quoted prices for identical assets and liabilities in active markets. These valuations are classified in Level 1. The valuations of certain contracts not classified as Level 1 may be based on quoted market prices received from counterparties and/or observable inputs for similar instruments. Transactions valued using these inputs are classified in Level 2. Certain derivatives are categorized in Level 3 due to the significance of unobservable or internally-developed inputs.

The following tables summarize our financial assets and liabilities that were accounted for at fair value on a recurring basis, categorized by level within the fair value hierarchy:
March 31, 2021
(in millions) Level 1 Level 2 Level 3 Total
Derivative assets
Natural gas contracts $ 12.3  $ 1.6  $   $ 13.9 
FTRs     0.9  0.9 
Coal contracts   2.6    2.6 
Total derivative assets $ 12.3  $ 4.2  $ 0.9  $ 17.4 
Investments held in rabbi trust $ 71.6  $   $   $ 71.6 
Derivative liabilities
Natural gas contracts $ 3.1  $ 1.0  $   $ 4.1 
Coal contracts   0.3    0.3 
Interest rate swaps   5.1    5.1 
Total derivative liabilities $ 3.1  $ 6.4  $   $ 9.5 

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