Rate Matters (Tables)

12 Months Ended

Dec. 31, 2024


	Rate increase	Return on Common Equity	Common Equity Component of Regulatory Capital Structure	Effective Date
Approved 2022/2023 settlement
Gas	0.96%	9.8%	55.6%	1/1/2023
Approved limited 2023 reopener(a)
Electric	9.01%	9.8%	55.6%	1/1/2023
Approved 2024/2025 rate proceeding(b)(c)
Electric	1.54%	9.7%	56.1%	1/1/2024
Gas	2.44%	9.7%	56.1%	1/1/2024
Electric(d)	2.63%	9.7%	56.1%	1/1/2025
Gas	1.32%	9.7%	56.1%	1/1/2025

(a)

The electric rate increase was driven by generation assets including MGE's investments in Badger Hollow II (solar), Paris (solar and battery), Red Barn Wind Farm (wind), and West Riverside (natural gas). In addition, the reopener request included an increase in fuel costs and the recovery of deferred 2021 fuel costs. The reopener also revised the depreciation schedule for Columbia Unit 2 and shared equipment to 2029 to align with the depreciation schedule for Unit 1.

(b)

The electric increase was driven by an increase in rate base including MGE's investments made in West Riverside, local solar, continued investment in grid modernization, as well as higher costs for transmission, pension and OPEB, and uncollectible costs (including costs previously deferred from prior years). This increase in electric costs is offset by a decrease in fuel costs and benefit from lower tax expense (including impacts from the Inflation Reduction Act). In addition, the PSCW authorized MGE to defer a recovery of and a return on costs associated for any change in the in service date for Paris and force majeure costs for Badger Hollow II and Paris that were not reflected in this rate filing. The PSCW also approved deferral of any differential in PTC tax credits reflected in rates and actual credits produced. These deferrals will be reflected in MGE's next rate case filing. The gas rate increases were also driven by MGE's investment made in grid modernization and higher pension and OPEB and uncollectible costs (including costs previously deferred from prior years). This increase in gas costs is offset by a tax benefit related to excess deferred taxes. Included in the gas residential rate is a reduction in the customer fixed charge.

(c)

The 2024/2025 rate order includes an earnings sharing mechanism, under which, if MGE earns above the authorized Return on Equity (ROE) in the rate order: (i) the utility will retain 100.0% of earnings for the first 15 basis points above the authorized ROE; (ii) 50.0% of the next 60 basis points will be required to be deferred and returned to customers; and (iii) 100.0% of any remaining excess earnings will be required to be refunded to customers. The earnings calculation excludes fuel rules adjustments. See "Fuel Rules" below.

(d)

The PSCW approved a 2025 Fuel Cost Plan in December 2024. The plan lowered the 2025 increase in electric rates to 2.63% to reflect lower expected fuel costs.

Deferred Fuel Rules

The following table summarizes deferred electric fuel-related costs:


	Fuel Costs (Savings) (in millions)	Refund or Recovery Period
2021	$3.3(a)	January 2023 through December 2023
2022	$8.8(a)	October 2023 through September 2024
2023	($7.2)(a)	October 2024 through December 2024
2024	($3.0)	(b)

(a)

There was no change to the refund or recovery in the fuel rules proceedings from the amount MGE deferred.

(b)

These costs will be subject to the PSCW's annual review of 2024 fuel costs, expected to be completed in 2025.