In a corner of southwestern Wisconsin, in a town called Eden, Bob Bishop spends his days farming land that has been in his family since the 1940s. He manages about 2,000 acres — some is pasture for his cattle, some is seeded with corn and soybeans. But 40% of his acreage, as he likes to say, will soon be farming the sun.
Under a 25-year lease to a large solar project called the Badger Hollow Solar Farm, Bishop has agreed to the installation of solar panels across hundreds of acres of land he previously used to grow crops. The project, which is operated by energy company Invenergy, is projected to total 3,500 acres in all and generate enough energy to power more than 77,000 homes. The developers say landowners will collect an estimated $59 million from leasing their property to the project.
In agreeing to set aside some of his land for solar energy production, Bishop is one of an increasing number of farmers in the Midwest looking to solar as a way to add to – or replace – money made growing crops, and potentially help fight climate change at the same time.
The moves are triggering some controversy, as critics say filling large swaths of land with massive installations of solar panels is unsightly and inhibits needed food production.
But advocates say using farmland to harness a clean, renewable energy source is a critical move in the face of harmful climate impacts. The Office of Energy Efficiency and Renewable Energy (EERE), a part of the US Department of Energy, says that solar energy has an important role in cutting greenhouse gas emissions, improving air quality and reducing the strain on water resources that otherwise are tapped for traditional energy production.
Bishop said he considers the transition of his land to solar production as a welcome move. His land will produce far more usable energy per acre than it would if he was still growing corn for ethanol, Bishop said. And while growing corn requires regular management and costly inputs to control weeds and pests, solar panels require little maintenance.
“It’s all revenue,” said Bishop.
And, he noted, with extra revenue coming in from solar projects, there’s less pressure to sell land when times get tough. “They will pass those dollars on to pay for car payments, house mortgages, college tuitions,” he said.
As adoption of solar projects on farmland climbs, many farmers and industry players are looking for ways to add solar to agricultural production without halting crop production, said Josh Arnold of the University of Wisconsin Office of Sustainability.
One answer is a practice called agrivoltaics, which is allowing farmers to use their land for some aspects of farming while also leasing the same land for solar projects.
Stacie Peterson, director of the AgriSolar Clearinghouse, which is funded by the Department of Energy, said that agrivoltaics projects are often more likely to be approved by community members who would rather not compromise the agricultural character of the landscape. One of the keys to getting such projects off the ground, she said, is to determine what is most important to the surrounding community, then develop the project to meet those needs.
“You’ve got to think about what your goal is,” she said. “Are you wanting to graze? Are you wanting a pollinator site? Are you wanting specialty crops? All three are possible.”
Agrivoltaics can include a variety of different strategies to mix agriculture with solar panels, but one promising technology involves farming row crops like corn and soybeans under solar panels. In order to make such a system work, the solar panels are hoisted higher into the air to allow for farming equipment to pass under.
The spacing between the panels, as well as the pattern of the panels above the crops, changes the amount of light available to the crops, which can help regulate their growth.
Sheep and solar
Bishop hopes that once the solar panels are set up on his land, he can graze sheep underneath. Grazing sheep can eliminate some of the need for maintenance like mowing or weeding under the panels and provides another income stream as lambs are sold for meat. Some solar projects in Minnesota have already implemented dual solar/sheep grazing systems.
The University of Wisconsin is now building a new research station in a partnership with energy company Alliant Energy to gather more information on how to effectively implement agrivoltaics. The university is planning a 2.25-megawatt solar array on a 10-acre parcel of agricultural land owned by the university.
Arnold, who is helping plan the project, said it is not been determined what types of crops will be planted beneath the solar panels. However, the researchers are aiming for crops that will grow well in the partially-shaded environment – optimizing plant production and energy production at the same time. The team is also thinking of implementing habitat for native pollinators under the solar panels, and studying the impacts of the solar array on the microclimate beneath, as well as the soil health of the land. Construction is planned to start next spring.
Similarly, researchers at Purdue University are testing out a 600-acre agrivoltaics project that positions solar panels over planted corn and soybean crops.
Optimizing plant production and energy production at the same time requires calibrating a number of factors, including the type of crop, the angle of the solar panels, the gaps between panels, and the height of the panels.
Previous research has found that various levels of shading from solar arrays can be beneficial to crops. For example, a 2019 study at the University of Arizona that studied peppers and cherry tomatoes found that water use efficiency and fruit production more than doubled in an agrivoltaic system compared to a traditional system. A 2021 study out of Germany determined that agrivoltaics helped winter wheat and potatoes survive a particularly dry and hot summer.
One barrier to implementing solar projects along with crop production is that most equipment used for crop farming won’t fit under conventional solar arrays.
But Andrew Poor, CEO of Midwest Agrivoltaics, a Missouri agrivoltaics design company, says his company has designed an agrivoltaic system that sits more than 12 feet off the ground – enough space to allow crops to grow and farmers to continue to use equipment beneath the panels.
“The agricultural industry and the solar industry do not have to be competitors against each other,” said Poor.
(Featured photo: Purdue University’s Sustainable Food Energy and Water Systems project, an agrivoltiacs research project in West Lafayette, Indiana. Credit: Purdue University).