NYSE: WEC

Available Information

Our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and any amendments to those reports are made available on our website, www.wecenergygroup.com, free of charge, as soon as reasonably practicable after they are filed with or furnished to the SEC. The SEC maintains an Internet site that contains reports, proxy and information statements, and other information regarding issuers that file electronically with the SEC at www.sec.gov.

Investors should note that WEC Energy Group announces material financial information in SEC filings, press releases, and public conference calls. In accordance with SEC guidelines, WEC Energy Group also uses the "Investors" tab on its website, www.wecenergygroup.com, to communicate with investors. It is possible that the financial and other information posted there could be deemed material information. The information on WEC Energy Group's website is not part of this document.

B. UTILITY ENERGY OPERATIONS

Wisconsin Segment

The Wisconsin segment includes the electric and natural gas utility operations of WE, WPS, WG, and UMERC.

Electric Utility Operations

Our electric utility operations include the operations of WE, WPS, and UMERC.

•WE generates and distributes electric energy to customers located in southeastern Wisconsin (including the metropolitan Milwaukee area), east central Wisconsin, and northern Wisconsin.

•WPS generates and distributes electric energy to customers located in northeastern and central Wisconsin.

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•UMERC generates and distributes electric energy to customers, including one iron ore mine owned by Tilden, located in the Upper Peninsula of Michigan.

Operating Revenues

For information about our operating revenues disaggregated by customer class for the years ended December 31, 2025, 2024, and 2023, see Note 1(d), Operating Revenues, and Note 4, Operating Revenues.

Electric Sales

Our electric energy deliveries included supply and distribution sales to retail, wholesale, and resale customers, and distribution sales to those customers who switched to an alternative electric supplier in the Upper Peninsula of Michigan. In 2025, retail revenues accounted for 92.3% of total electric operating revenues, wholesale revenues accounted for 1.9% of total electric operating revenues, and resale revenues accounted for 4.8% of total electric operating revenues. See Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Results of Operations – Wisconsin Segment Contribution to Net Income Attributed to Common Shareholders for information on MWh sales by customer class.

Our electric utilities are authorized to provide retail electric service in designated territories in the state of Wisconsin, as established by indeterminate permits and boundary agreements with other utilities, and in certain territories in the state of Michigan pursuant to franchises granted by municipalities.

We provide wholesale electric service to various customers, including electric cooperatives, municipal joint action agencies, other investor-owned utilities, municipal utilities, and energy marketers.

The majority of our sales for resale are conducted within an energy market operated by MISO at market rates based on the availability of our generation and market demand. Retail fuel costs are reduced by the amount that revenue exceeds the cost of sales derived from these opportunity sales.

Our electric utilities buy and sell electric power by participating in the MISO Energy Markets. The cost of our individual generation offered into the MISO Energy Markets compared to our competitors affects how often our generating units are dispatched and whether we buy or sell power. For more information on the MISO Energy Markets, see E. Regulation.

Steam Sales

WE has a steam utility that generates, distributes, and sells steam supplied by the VAPP to customers in metropolitan Milwaukee, Wisconsin. Steam is used by customers for processing, space heating, domestic hot water, and humidification. Annual sales of steam fluctuate from year to year based on system growth and variations in weather conditions.

Electric Sales Forecast

Our service territory experienced higher weather-normalized retail electric sales in 2025, compared with 2024. We currently forecast retail electric sales volumes, excluding the Tilden mine located in the Upper Peninsula of Michigan, to increase 1.6% for 2026, compared with 2025, assuming normal weather. Excluding the very large data center customers, we currently forecast sales volumes to be relatively flat for 2026, assuming normal weather.

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Customers

Year Ended December 31

(in thousands)202520242023

Electric customers – end of year

Residential1,512.2 1,499.4 1,487.9

Small commercial and industrial181.9 180.8 179.0

Large commercial and industrial0.8 0.8 0.8

Wholesale and other1.7 1.7 1.6

Total electric customers – end of year 1,696.6 1,682.7 1,669.3

Steam customers – end of year0.4 0.4 0.4

Electric Commercial and Industrial Retail Customers

We provide electric utility service to a diversified base of customers in industries such as metals and other manufacturing, paper, governmental, food manufacturing, and health services.

Electric Generation and Supply Mix

Our electric supply strategy is to provide our customers with energy from a diverse generation portfolio that balances a stable, reliable, and affordable supply of electricity with environmental stewardship. Through our participation in the MISO Energy Markets, we supply a significant amount of electricity to our customers from generation that we own. We supplement our internally generated power supply with long-term PPAs, including the Point Beach PPA discussed under the heading "Power Purchase Commitments," and through spot purchases in the MISO Energy Markets. We also sell excess power supply into the MISO Energy Markets when it is economical, which reduces net fuel costs by offsetting costs of purchased power. On a real time basis, the MISO Energy Market continuously evaluates system load requirements and dispatches the lowest-cost generation resources, while respecting any limitations on the transmission system.

The table below indicates our sources of electric energy supply as a percentage of sales for the three years ended December 31, as well as estimates for 2026:

Estimate (1)
Actual

2026202520242023

Company-owned generation:

Coal30.7 %30.5 %29.4 %29.0 %

Natural gas:

Combined cycle27.7 %24.1 %27.2 %28.7 %

Steam turbine0.5 %0.8 %1.0 %0.9 %

Natural gas/oil peaking units5.0 %7.9 %7.2 %5.5 %

Renewables (2)
9.1 %8.4 %6.5 %5.5 %

Total company-owned generation73.0 %71.7 %71.3 %69.6 %

Power purchase contracts:

Nuclear19.2 %19.8 %20.3 %20.1 %

Renewables (3)
1.6 %1.5 %1.9 %2.0 %

Other— %0.2 %— %0.1 %

Total power purchase contracts20.8 %21.5 %22.2 %22.2 %

Purchased power from MISO6.2 %6.8 %6.5 %8.2 %

Total purchased power27.0 %28.3 %28.7 %30.4 %

Total electric utility supply100.0 %100.0 %100.0 %100.0 %

(1) The values included in the estimate assume a natural gas price based on the December 2025 NYMEX.

(2) Includes hydroelectric, biomass, solar, BESS, and wind generation.

(3) Includes hydroelectric, wind, and customer-owned renewable generation.

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Electric Generation Facilities

Our generation portfolio is a mix of energy resources having different operating characteristics and fuel sources. We own 8,375 MWs of generation capacity, including wholly owned and jointly owned facilities. We Power's generating units are also included in the generation capacity. Our generation facilities include natural gas-fired plants, coal-fired plants, renewable generation, and BESSs. Certain of our natural gas-fired generation units have the ability to burn oil if natural gas is not available due to delivery constraints. For more information about our facilities, see Item 2. Properties.

We are engaged in discussions with a small number of customers to provide power to large-scale data centers being constructed in our service territories. We anticipate electric demand growth in the years ahead from these VLCs. Subject to pending regulatory approvals from the PSCW as discussed below, WE is planning to make significant infrastructure investments in new natural gas-fired plants, wind, solar and battery projects, and other generation and distribution assets to power and serve these large-scale data centers and other projects. We are working closely with the new data center customers to provide bespoke resources, which are generation resources assigned to the VLCs that match their growing demand in order to minimize the impact on our other retail customers.

Supporting Economic Growth Within Our Communities

Our capital plan reflects the planned retirement of our older, fossil-fueled generation, which we expect to replace with natural gas-fired generation and zero-carbon-emitting renewables. These retirements are intended to address compliance with EPA regulations established under the CAA, as well as contribute to meeting our goal to reduce CO2 emissions from our electric generation. When taken together, the retirements and new investments in natural gas generation and renewables discussed in more detail below should better balance our supply with our demand, while helping to address compliance and maintaining reliable, affordable energy for our customers. As described in the preceding section, we are planning to make significant investments in generation and distribution assets for the future demands of VLCs.

Environmental Goal

Our long-term goal is to achieve net carbon neutral electric generation by the end of 2050. We expect to achieve this goal by continuing to make operating refinements, retiring less efficient generating units, and executing our capital plan. We expect to use coal only as a backup fuel by the end of 2030 and to be in a position to eliminate coal as an energy source by the end of 2032. As of the end of 2025, our electric generation fleet has achieved a 53% reduction in carbon emissions from the 2005 baseline.

As part of our path toward this goal, we have started implementing co-firing with natural gas at the ERGS coal-fired units and at Weston Unit 4. Additionally, we have retired nearly 2,500 MWs of fossil-fueled generation since the beginning of 2018, which includes the 2024 retirements of OCPP Units 5 and 6, the 2019 retirement of the PIPP, and the 2018 retirements of the Pleasant Prairie power plant, the Pulliam power plant, and the jointly-owned Edgewater Unit 4 generating unit. See Note 6, Regulatory Assets and Liabilities, for more information related to certain of these power plant retirements. We expect to retire approximately 900 MWs of additional coal-fired generation by the end of 2031, which includes the planned retirements of OCPP Units 7 and 8 and Weston Unit 3. See Note 7, Property, Plant, and Equipment, for more information.

See Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations – Corporate Developments for more information on our capital plan.

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