2025 Carbon Emissions
Our commitment to a cleaner energy future
MGE is committed to lowering carbon emissions as quickly as possible while maintaining safe, reliable, affordable energy for our customers. Our goals and decarbonization strategies are aligned with climate science. Continuing to invest in carbon-free renewable energy is a key strategy toward deep decarbonization of our energy supply serving customers.
MGE determines its annual carbon emissions profile based on the amount of energy generated and the sources used to generate it each year. Our carbon dioxide (CO₂) emissions are calculated from:
- Energy produced by generating units owned by MGE.
- Energy supplied through power purchase agreements.
- Energy purchased on the Midcontinent Independent System Operator (MISO) market; MISO is the regional grid operator covering our service territory.
The market purchase emission rate is based on a MISO regional rate.
Fluctuations year-to-year in MGE's carbon emission rate (and in our renewable energy percentage) are normal. From year to year, the sources used to serve our customers vary in percentage based on how much the sun shines, how much the wind blows and other energy market conditions. MGE continues to grow our use of renewables to decarbonize our energy supply as we work toward net-zero carbon electricity.
2025 Carbon and Renewable Energy Snapshot
| Overall CO2 emission rate | 1.34 lb/kWh |
| Percent reduction from 2005 | 37% |
| Residual CO2 emission rate | 1.41 lb/kWh |
| Overall renewable percentage | 27% |
| Residual renewable percentage | 24% |
See definitions below for more information.
In 2025, renewable energy accounted for about 27% of MGE’s overall generation mix serving customers—an increase of about 3% from 2024.
The residual renewable energy percentage represents the renewable energy available to customers who are not participating in one of MGE’s renewable energy programs (Green Power Tomorrow, Renewable Energy Rider or Shared Solar). MGE’s residual renewable energy percentage was about 24% in 2025.
MGE’s overall CO₂ levels in 2025 were about 37% less than our baseline levels in 2005. MGE's overall CO₂ emission rate was about 1.34 lb/kilowatt-hours (kWh).
Similar to our residual renewable percentage, the residual CO₂ rate represents the carbon rate for MGE customers who are not already subscribed to a renewable energy (or green tariff) program. MGE's residual CO₂ rate was about 1.41 lb/kWh in 2025.
Definitions
MGE's overall CO2 emission rate represents the carbon intensity from the total of all energy sources in MGE's energy mix supplied to all customers.
MGE's residual CO2 emission rate represents the carbon intensity of MGE-supplied electricity after accounting for (or taking out) the renewable energy delivered on behalf of customers who participate in our optional renewable energy programs such as Green Power Tomorrow, Renewable Energy Rider and Shared Solar. This emission rate applies to all energy not included in those specific programs.
MGE's overall renewable percentage represents the percentage of renewable energy in MGE's energy mix supplied to all customers.
The residual renewable energy percentage represents the renewable energy available to customers who are not participating in one of MGE’s renewable energy programs (Green Power Tomorrow, Renewable Energy Rider or Shared Solar). This percentage applies to all energy not included in those specific programs.
Decarbonization is the reduction and removal of carbon dioxide and other greenhouse gases from the atmosphere. MGE continues to invest in carbon-free energy generation like wind and solar as a strategy toward deep decarbonization of our energy supply serving customers.
Renewable energy is power generated from natural carbon-free sources, such as sunlight and wind, that naturally replenish themselves. Unlike energy generated by fossil fuels, renewable energy does not deplete natural resources and produces little greenhouse gas emissions.
A green tariff is an optional electricity pricing structure from a regulated utility that allows customers to source their energy from renewable resources like solar or wind. When participating in a green tariff program, the customer's electricity use is offset by clean energy generated and verified by Renewable Energy Certificates (RECs).
MGE is a member of the Midcontinent Independent System Operator (MISO). MISO is a not-for-profit organization that is responsible for the coordination and delivery of reliable electric power across all or parts of 15 states, including Wisconsin.
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