Missouri is the No. 3 producer of beef cattle in the country, and University of Missouri researchers aim to develop a project that would study how farmers can produce both beef and solar energy on the same land.
Agrivoltaics — a combination of the words “agriculture” and “photovoltaic” — is an emerging strategy to enable two uses of a single piece of land. A solar array generates power while farmers cultivate produce, graze livestock or plant ecosystem-supporting native grasses underneath and around the panels.
Research trials across the country show agrivoltaics can be beneficial for farms growing hand-harvested produce and herbs. Sheep grazers are also finding success feeding their flock from the forage around a solar power plant. Now, researchers at Midwestern universities, including Mizzou, are studying whether agrivoltaics can work for farmers growing the region’s most popular agricultural products — commodity crops and beef.
“I definitely think it'll work. Now, getting it funded may be a different story,” said Dusty Walter, director of the Central Missouri Research, Extension and Education Center. He oversees 14 working farms where university scientists and students conduct agriculture studies.
Mizzou is currently working to secure funding to build a solar array within a cattle pasture at the college’s South Farm research site to test whether cows and solar energy can coexist. The South Farm, five miles south of Columbia, is where the university’s beef research and training takes place, among other agriculture studies.
Walter said he’s hoping to secure a partnership with a local power company for the research project and is seeking grants to build the infrastructure.
“A lot of the solar panel grants target climate change and that's not necessarily something that (at) the federal level is being as supported right now,” he said.
To raise beef among a solar array, there needs to be space for the cows to roam and graze. Although blueprints aren't finalized, Walter anticipates the Mizzou cattle agrivoltaics project solar panels will be raised to 12 feet above the ground — higher than a traditional ground-mounted array — with extra spacing between rows to allow the sun to also support grass growth.
Walter said the university’s previous research on agroforestry is informing the design of the future solar demonstration site.
“We've learned a lot about the different types of forages that will grow under different limited light environments — the shade that’s created by a tree — and so we're mimicking that when I start talking agrovoltaics and how we might put solar panels on the beef farm,” he said.
As utility companies expand renewable energy sources such as wind and solar, developers are approaching farmers about the opportunity to lease their cleared, flat land for solar panels.
Walter said testing what types of agriculture can coexist alongside solar power plants provides information for Missouri farmers presented with that possibility.
“The university is in the business of experimenting — experimenting in ways that give good information so that people can make good decisions about adoption on a number of fronts,” he said.
Walter said once the solar array is built, researchers will study a variety of its impacts on a cattle operation — everything from forage quality to soil moisture retention to economic analysis.
The experiment will be especially focused on cattle growth and performance when grazing among the energy infrastructure, including whether shade provided by solar panels reduces cows’ stress in extreme heat.
Harvesting crops — and the sun
The United States contains more than 880 million acres of farmland, according to the USDA Census of Agriculture. Experts estimate solar development would be a small fraction of that scale — about 2%, said Madhu Khanna, a professor of environmental economics at the University of Illinois and director of the university's Institute for Sustainability, Energy and Environment.
As large scale solar power plants are built across the country, it's leaving some in rural America feeling their landscape, and lifestyle, are changing before their eyes.
“A big reason for the opposition that we are seeing towards solar from agriculture communities is because of the loss of access to land and the loss of farming lifestyle,” said Khanna, who is leading a multi-state study of agrivoltaics.
An estimated 83% of new solar development will occur on land previously used for agriculture, according to American Farmland Trust, a national land preservation organization that supports agrivoltaics.
“A lot of projects are getting delayed and canceled because of community opposition,” Khanna said.
Spurred by a federal grant, Khanna and her team have been studying how agrivoltaics works for a variety of types of farming across four states — Alabama, Illinois, Colorado and Arizona. She believes agricultural communities would be more open to solar development if it meant they didn’t have to give up farming.
“Agrivoltaics might, in fact, be preferred and be a way for a community to accept solar energy generation, and a way for solar developers that despite the higher costs, they might be willing to do it,” she said.
Whereas research shows the shade created from rows of solar panels can help vegetables and herbs grow, agrivoltaics for Midwestern commodity crops may be more complicated.
Some of the most popular commodity crops — soybeans, corn, wheat — generally need full sun to succeed, and competing with panels for sunlight could curb its growth, a con for farmers.
“They also require very heavy, large equipment that requires a lot of space,” Khanna said.
Combines and other farm machinery can sprawl anywhere from 8 to 60 feet wide. Making that much room between rows of solar panels decreases the amount of power that can be generated per acre — a con for energy developers.
Despite the odds, Khanna is looking for solutions to make agrivoltaics an attractive possibility for both Midwestern commodity farmers and energy companies. Amid 54 acres of solar panels, Khanna and her team are studying whether soybeans and sorghum can succeed within a solar array.
Khanna said preliminary research shows agrivoltaics could reduce the yield of those crops by 15-20% — a serious negative for farmers operating a business with slim margins.
However, leasing land to solar developers could provide an additional income stream for farmers, and research shows crops have a cooling effect on solar panels, making them run more efficiently.
Khanna emphasizes that although solar generation and row crops seem to be at odds right now, changing technologies in each industry could decrease barriers for the sun-thirsty products to coexist.
“We’re really at the beginning of this whole research,” she said. “There's a long way to go before we can really conclude what role — and where — agrivoltaics can play (and) can help.”
Progress for grazers
Stacie Peterson has worked in the energy industry for more than 20 years.
“It always troubled me looking at solar sites, you know, what is happening with the land underneath that? What happens in perpetuity?” she remembers thinking. “Are these lands being cared for? Is there a better way to do it?”
Now, as executive director of the American Solar Grazers Association, Peterson advocates for using the grasses underneath solar arrays to feed livestock as a better way. The organization has 1,200 members and encourages energy developers to adopt grazing agrivoltaics.
Whereas goats tend to chew wires and cattle require higher panels, sheep are able to graze around the standard solar power plant design.
“Sheep are the easiest plug-and-play option for livestock. No questions asked,” said Peter Schmitt, director of project development for US Solar, an energy company based in Minneapolis. “We also just are not a particularly large sheep producing country, yet.”
US Solar hosts agrivoltaics on majority of its sites, whether that be native grasses for pollinator habitat, sheep grazers, or in one instance, vegetable crop production. Schmitt said it's essential the industry figures out how to make agrivoltaics successful for cattle because many U.S. farmers already produce large amounts of milk or beef.
“We want you to farm. We want you to be successful. Also, there's this other thing that can be helpful for society in a different way that can definitely be married with what you're doing,” Schmitt said.
Peterson said more research is needed for cattle solar grazing to advance. However, she fears that’s less likely to happen as renewable energy is de-prioritized on the federal level.
“As solar faces headwinds, so will agrivoltaics,” she said.
