Solar Panels on Farms: Where Agrivoltaics Pays Off and Where It Costs You
The pitch for agrivoltaics - co-locating solar panels and crops on the same land - is compelling on paper. Farmers get electricity income, developers get land access, and solar panels get cooled by crop transpiration. But this dual-use promise depends entirely on what crop you grow and where you grow it, according to a University of Illinois Urbana-Champaign study published in the Proceedings of the National Academy of Sciences.
The research team spent years building and validating a process-driven model integrating energy, water, and plant-soil dynamics before layering on an economic analysis. The result is the most geographically comprehensive assessment of Midwest agrivoltaics to date - and its findings are more conditional than either advocates or critics tend to acknowledge.
What the Midwest Looks Like in 33% Shade
The simulations assumed solar arrays covering 33% of each farm site - a density common in commercial agrivoltaic installations. Across 15 years of varying climate conditions, the outcome diverged sharply based on moisture regime.
In the humid eastern Midwest, where water is rarely the limiting factor for crop growth, shade is simply a loss. Photosynthesis drops, light interception falls, and maize yields declined by an average of 24%. Soybean losses ran 16%. At those scales, agrivoltaics cost farmers money rather than earning it.
In semi-arid regions further west, the calculus flips. There, heat and water stress are the dominant constraints. Solar shading reduces both. Maize yield losses were moderated compared to humid zones, and soybean yields actually increased by 6%. The crop benefited from reduced evapotranspiration and cooler temperatures during the critical growing period.
"In the semi-arid Midwest, shading alleviated water stress, moderating maize yield losses and increasing soybean yields by 6%," said Mengqi Jia, the study's first author. "That contrast with humid regions is the central finding of this work."
The Economics Are Trickier Still
Crop yield impacts are only part of the financial picture. Agrivoltaic installations cost more than conventional ground-mounted solar because panels must be elevated to allow farming machinery to pass beneath - roughly double the standard mounting height in most designs. That added cost falls primarily on solar developers, not farmers, which creates a structural problem: the party bearing the cost and the party reaping the crop benefit are not the same.
"Utility-scale solar developers would therefore need policy or market incentives in order to adopt agrivoltaics with row crops," noted Madhu Khanna, one of the study's co-authors. Without such incentives, even the semi-arid soybean case - where there is a genuine crop benefit - may not pencil out for developers who can install conventional panels at lower cost.
The simulations also examined purely economic outcomes per acre. Combined crop plus energy revenues in the soybean/semi-arid combination produced what the team characterized as "win-win" conditions - net benefits to both farmers and developers. But those conditions are geographically specific and require aligned market factors, including commodity prices and land-lease rates that fluctuate year to year.
What the Model Can and Cannot Tell You
The integrated modeling framework - validated first in the Journal of Advances in Modeling Earth Systems before being extended to economics - is genuinely new. Previous agrivoltaic studies have typically been site-specific trials with short time horizons. Running 15-year simulations across diverse climate zones with coupled energy, water, and economic outputs at once provides a different kind of evidence: not what happened at one farm in one year, but what the range of outcomes looks like under realistic climate variability.
Limitations are real. The model uses representative soil types and climate records; individual farm variability could push outcomes in either direction. Panel design - height, tilt angle, spacing - matters considerably and is simplified in the simulations. The analysis covers corn and soybeans, the Midwest's dominant commodity crops, but does not speak to vegetables, fruits, or specialty crops that may respond differently to shade and that command higher per-acre returns.
The study does not address grid-scale implications of widespread agrivoltaic adoption, nor does it model competition with conventional solar for available capital.
For policymakers, the practical guidance is clear: region-specific design and incentive structures are not optional. Blanket agrivoltaic promotion, or blanket skepticism, misreads the landscape. Whether the economics can be made to work broadly enough to matter for the energy transition depends on policy choices that are not yet made.