About the project


The Onion River Solar Project is an estimated 150-megawatt (MW) solar project located in Sheboygan County, Wisconsin. The Onion River Solar Project will connect into the electrical transmission grid directly through the local substation. Once complete, the project will positively impact the environment and generate enough clean, low-cost energy to power tens of thousands of homes.

Fast facts

  • Location: Town of Holland
  • Acreage: 1,000 acres
  • Timeline: Construction began in the summer of 2022 and is expected to be completed by late 2023.

Project updates


January 11, 2024

We're excited to announce that we placed the Onion River Solar Project into service in December! This final construction update highlights the work needed to get the project to the finish line as well as some of the local benefits we expect this project to bring for the next 30 years. Read further in our latest project update..pdf

Thank you for your interest in the Onion River Solar Project!

Economic benefits


  • The Onion River Solar Project will be a significant source of new local tax revenue, providing approximately $600,000 in annual shared revenue for the Town of Holland and Sheboygan County.
  • During construction, between 100 and 200 jobs will be created.
  • Once operational, a few full-time employees will help ensure the project is running smoothly.
  • Alliant Energy will provide lease payments to landowners in the project area for the 30-year lifespan of the project.
  • In addition, soil recovery during the project’s lifespan will protect agricultural land and preserve its value for future generations.

Environmental benefits


  • This project will feature grass and seed mixes surrounding the solar panels and throughout the solar arrays that will help build soil nutrients and create a pollinator-friendly habitat. Pollinator-friendly vegetation has been proven to prevent soil erosion and add benefit to high-value crops, creating a win-win for both human and wildlife communities.
  • Once the grass matures in four years following construction, the water quality of surrounding waterbodies is expected to improve because of reduced nitrogen, phosphorus, sediment, and biological oxygen demand entering these waterbodies. This improves the ecological health of the watershed and the quality of life for all inhabitants, as high loadings of these pollutants can produce excess algae growth and degrade the habitat in adjacent waterbodies.
  • Requiring only sunlight for fuel, the Onion River Solar Project represents a long-term reduction of traditional fossil fuels for energy generation, creating a clean environment and clean energy future for Wisconsin and the Midwest.

Solar and the Clean Energy Blueprint


The Onion River County Solar Project is one of the 12 solar projects Alliant Energy has received approval to own and operate in Wisconsin. The projects span dozens of communities across nine counties. Collectively, these projects will add nearly 1,100 MW of solar energy generation to the state’s energy grid by the end of 2023 – enough to power nearly 300,000 homes.

These projects demonstrate our commitment to advancing clean energy and strengthening the communities we serve. They create an economic boost for communities and landowners while providing customers with reliable, environmentally friendly energy for decades to come.

Collectively, our solar projects, along with the rest of our Clean Energy Blueprint, are also a smart investment that will help customers avoid more than $1.6 billion in long-term costs. They will also provide steady revenue through new construction opportunities, create an estimated 2,000 construction jobs and provide approximately $300 million in revenues to local communities and landowners over an estimated project lifespan of 30 years.

As we move toward creating a healthier environment, these initiatives are positioning Alliant Energy to achieve net-zero carbon dioxide emissions from the electricity we generate by 2050.

Visit our Powering What's Next site for more details on our Clean Energy Blueprint.

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