MGE ENERGY INC

nt 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 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. See Footnote 3 of Notes to Consolidated Financial Statements under Item 8, Financial Statements and Supplementary Data, of MGE Energy's and MGE's 2023 Annual Report on Form 10-K (the 2023 Annual Report on Form 10-K).

The accompanying consolidated financial statements as of March 31, 2024, and during the three months ended March 31, 2024, 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 2023 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 on pages 59 through 107 of the 2023 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.

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 MISO to retire Columbia Units 1 and 2. The co-owners intend to retire Unit 1 and Unit 2 by June 2026. Final timing and retirement dates are subject to change depending on operational, regulatory, and other factors. As of March 31, 2024, early retirement of Columbia was probable.

The net book value of our ownership share of this generating unit was $119.5 million as of March 31, 2024. This amount was classified as plant to be retired within "Property, plant, and equipment, net" on the consolidated balance sheets. 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 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 March 31, 2024.

New Accounti