Summary of Significant Accounting Policies

6 Months Ended

Jun. 30, 2025

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Summary of Significant Accounting Principles

Summary of Significant Accounting Policies – MGE Energy and MGE.

a.Basis of Presentation.

This report is a combined report of MGE Energy and MGE. References in this report to "MGE Energy" are to MGE Energy, Inc. and its subsidiaries. References in this report to "MGE" are to Madison Gas and Electric Company.

MGE Power Elm Road and MGE Power West Campus own electric generating assets and lease those assets to MGE. Both entities are variable interest entities (VIE) under applicable authoritative accounting guidance. MGE is considered the primary beneficiary of these entities as a result of contractual agreements. As a result, MGE has consolidated MGE Power Elm Road and MGE Power West Campus in its financial reports. See Footnote 3 of the Notes to the Consolidated Financial Statements under Item 8, Financial Statements and Supplementary Data, of MGE Energy's and MGE's 2024 Annual Report on Form 10-K (the 2024 Annual Report on Form 10-K).

The accompanying consolidated financial statements as of June 30, 2025, and during the three and six months ended June 30, 2025, as applicable, are unaudited but include all adjustments that MGE Energy and MGE management consider necessary for a fair statement of their respective financial statements. All adjustments are of a normal, recurring nature except as otherwise disclosed. The year-end consolidated balance sheet information was derived from the audited balance sheet appearing in the 2024 Annual Report on Form 10-K but does not include all disclosures required by accounting principles generally accepted in the United States of America. These notes should be read in conjunction with the financial statements and the notes thereto located on pages 53 through 99 of the 2024 Annual Report on Form 10-K.

b.Cash, Cash Equivalents, and Restricted Cash.

The following table presents the components of total cash, cash equivalents, and restricted cash on the consolidated balance sheets.

	MGE Energy				MGE
	June 30,		December 31,		June 30,		December 31,
(In thousands)	2025		2024		2025		2024
Cash and cash equivalents	$	10,569	$	21,302	$	3,525	$	16,865
Restricted cash		869		1,113		869		1,113
Receivable - margin account		1,698		2,081		1,698		2,081
Cash, cash equivalents, and restricted cash	$	13,136	$	24,496	$	6,092	$	20,059

Cash Equivalents

All highly liquid investments purchased with an original maturity of three months or less are considered to be cash equivalents.

Restricted Cash

MGE has certain cash accounts that are restricted to uses other than current operations and designated for a specific purpose. MGE's restricted cash accounts include cash held by trustees for certain employee benefits and cash deposits held by third parties. These are included in "Other current assets" on the consolidated balance sheets.

Receivable – Margin Account

Cash amounts held by counterparties as margin collateral for certain financial transactions are recorded as Receivable – margin account in "Other current assets" on the consolidated balance sheets. The costs being hedged are fuel for electric generation, purchased power, and cost of gas sold.

c.Property, Plant, and Equipment.

Columbia.

An asset that will be retired in the near future and substantially in advance of its previously expected retirement date is subject to abandonment accounting. In the second quarter of 2021, the operator of Columbia received approval from Midcontinent Independent System Operator (MISO) to retire Columbia Units 1 and 2. The co-owners intend to retire Unit 1 and Unit 2 by the end of 2029. Final timing and retirement dates continue to be evaluated and depend upon operational and regulatory considerations, capacity needs and availability, and other factors impacting one or more of the Columbia co-owners. As of June 30, 2025, early retirement of Columbia Unit 1 and 2 was probable.

Our ownership share of Columbia assets was classified as plant to be retired within "Property, plant, and equipment, net" on the consolidated balance sheets contained in the 2024 Annual Report on Form 10-K. Assets for Columbia Unit 1 and Unit 2 are currently included in rate base, and MGE continues to depreciate them on a straight-line basis using the composite depreciation rates approved by the Public Service Commission of Wisconsin (PSCW) that include retirement dates of 2029 for both Units.

If it becomes probable that regulators will disallow full recovery or a return on the remaining net book value of a generating unit that is either abandoned or probable of being abandoned, an impairment loss would be required. An impairment loss would be recorded to the extent that the remaining net book value of the generating unit exceeds the present value of the amount expected to be recovered from ratepayers. No impairment was recorded as of June 30, 2025.