Geothermal

​Geothermal power plants that generate electricity tap into naturally existing hot water or steam reservoirs trapped in rock formations.  These power plants are usually found in tectonically active areas such as the Western United States, where geology is particularly well suited for geothermal power generation. Geothermal power plants use the naturally occurring steam, heat, or hot water from geothermal reservoirs to help spin turbine generators that produce electricity. For more information on geothermal electricity generation, visit University of Wisconsin Stevens Point geothermal page Geothermal - Renewable Energy Education | UWSP and the U.S. Department of Energy’s (U.S. DOE) geothermal webpage Geothermal Electricity Generation | Department of Energy. 

Wisconsin does not have any geothermal electricity generating power plants, as the state’s geology is not well suited for geothermal electricity generation. Geothermal power plants require heat, fluid, and rock permeability and are best suited for areas with tectonic activity and high heat closer to the earth’s surface like California and the Western United States.  In contrast, parts of Wisconsin have hard granite bedrock that is difficult to drill through. The U.S. DOE and national laboratories have been working on Enhanced Geothermal technology that will allow geothermal energy to be produced in more locations across the nation. Improvements in drilling technology and methodology allow for deeper wells to reach hotter temperatures, along with new geothermal generating methods, like closed loop systems, are expanding the reach of geothermal electricity generation. To learn more about Enhanced Geothermal, visit U.S. DOE’s Enhanced Geothermal Systems webpage: Enhanced Geothermal Systems | Department of Energy, watch this U.S. DOE video Energy Anywhere: The Power of Enhanced Geothermal Systems or read the National Laboratory of the Rockies report on Enhanced Geothermal Enhanced Geothermal Shot Analysis for the Geothermal Technologies Office.

​

Currently, there are not tax credits of incentives for homeowners to install geothermal ground source heat pump systems. However, commercial building owners may be eligible for tax credits under the Investment Tax Credit (ITC, Section 48). Businesses may be eligible for “bonus credits” of up to 30 percent total if their projects meet specific prevailing wage, domestic content, or energy community requirements. View the Internal Revenue Service's Advanced Energy Project Credit page for more information.  

Comfort: Ground source heat pumps provide a consistent flow of air, reducing temperature fluctuations found in some other HVAC systems. 

Efficiency: A geothermal heat pump system uses very little electricity. The system only uses electricity to power a fan that moves the heat, rather than a traditional heating, ventilation, and cooling system that warms or cools the air. Additionally, the building gets both heating and cooling in one system. 

Long-term Costs and Lower Electric Bills: With little electricity used to heat and cool a building, electric bills in both winter and summer can be lower than with other heating and cooling systems. Additionally, geothermal systems have a longer life span than other types of heating and cooling systems. The underground loop system can last up to 50 or more years, and the lack of outdoor equipment means less exposure of its main components to weather.

Cleaner and Environmentally Friendlier: Ground source heat pump systems do not have the danger of gas leaks or carbon monoxide poisoning.  Because they do not use fossil fuels, geothermal heat pumps are non-emitting options for customers to heat and cool buildings.

Cold Weather Climate: Ground source heat pumps perform well during Wisconsin’s cold winters. Because they can rely on stable underground temperatures, ground source heat pumps can be effective in maintaining their high efficiency and consistent heat outputs even during extended sub-zero periods.​

​​Geothermal in Wisconsin

​One of the world’s largest geothermal heating and cooling systems is in Verona, Wisconsin, at the Epic Systems Corporation’s (Epic’s) campus. Below the campus there are approximately 6,100 boreholes across 4 borefields, with 2 lake exchange systems.  Epic’s data centers need to be cooled constantly and by using geothermal, the company can do that more effectively and efficiently. According to the U.S. Department of Energy, “Excess heat from the data center is transferred into the relatively cooler ground beneath the building, maintaining optimal temperature in the data center with much less electricity than traditional air conditioning.”

In Green Bay, Nature’s Way is installing a geothermal heating and cooling system at their facility. In summer 2025, crews began drilling 280 500-foot-deep wells for the system. The company expect the system to come online in fall 2026, cutting the site’s emissions by about 20 percent.

​​​Applicant	​Application	​​Type of Project
​Children's Museum of Eau Claire	​PSC REF#: 403454	​Implementation
​Benedictine Life Foundation, Inc.	​PSC REF#: 428881	​Implementation
​Northland College	​PSC REF#: 428855	​Implementation
​Marquette University (and partners)	​PSC REF#: 457863	​Planning—Marquette University Final Report
​Kaukauna Utilities	​PSC REF#: 493051	​Implementation
​City of Racine	​PSC REF#: 492341	​Planning
​City of Madison/Monona Terrace	​PSC REF#: 492914	​Planning—Monona Terrace Geothermal Feasibility Study
​Marion School District	​PSC REF#: 495099	​Planning—Marion Final Report​

​