Letter: Solar’s potential is a reason for guidance not abandon

ByLetter to the Editor Reading Time: 4 minutes

As mentioned, a significant portion of the farmland used to produce ethanol also yields a co-product. Approximately one-third of the corn per bushel will be used to produce high-protein animal feed.1 

In my previous letter, I briefly mentioned agrivoltaics, the dual use of land for solar and agriculture. Many solar farms raise livestock that freely graze the land under their panels. It is my firm belief that solar farms that can produce food should produce food. I feel this was absent from Mr. Kaltenbache’s response.

While growing corn for ethanol is also an excellent example of dual-land use, recent studies suggest that one of its intended benefits may be struggling. Ethanol was introduced into our fuel to reduce exhaust emissions and increase engine performance. However, a five-year long study released in 2022 2,3 suggests subsidizing farmers to grow corn for ethanol has resulted in “increased fertilizer use, water pollution, and likely at least 24 percent more emissions than gasoline.” 2  Subsidies have also resulted in the persistent increase in corn prices that has spilled into other crops.3 This does not mean ethanol farming is “bad.” It means that we must hold industries accountable and monitor results. 

On that note, can a solar farm with solar grazing have agricultural benefits? A study released in 20254,5,6 found solar grazing tended to address concerns about soil conditions compared to when solar farm lands go unused. The study found grazing on solar sites can “increase soil carbon content, posing potential for this practice to enhance [carbon] sequestration on solar sites.” 5 It also found “improved moisture retention and less compaction.” 6 Solar grazed land also has less need for fertilizer and pesticides thus reducing water pollution. 

A separate review7 found “the addition of solar modules to a pasture reduced livestock radiant heat load and livestock body temperature.” Basically, livestock preferred the shade. 

Regardless, agrivoltaics needs more study. A Multi-Disciplinary Review7 cites zoning and other laws make this very difficult. 

That being said, Mr. Kaltenbacher is not wrong that some solar farms have misused the land on which they sit. I would argue this is always the case when an industry sees growth. However, this is a reason to guide its implementation, like the regulations that gave us ethanol farming, not abandon it. 

Regardless of the industry, we need to be steadfast in protecting our resources and our community.

Maybe if we are lucky we will see a healthier and more thoughtful regulation on solar than we have seen on fossil fuels.

Joseph Huddleston
Jasper

Sources:

  1. https://iowarfa.org/ethanol-center/ethanol-co-products/distillers-grains-facts/ two-thirds of a bushel of corn is used to process ethanol and the remaining one-third goes into distillers grains, a high-protein livestock feed.
  2. https://civileats.com/2022/02/14/how-corn-ethanol-for-biofuel-fueled-climate-change/ The Renewable Fuel Standard promised to pay farmers to fight climate change and boost U.S. energy independence. Instead, a new five-year study of its impact on land use suggests it led to increased fertilizer use, water pollution, and likely at least 24 percent more emissions than gasoline.
  3. https://www.pnas.org/doi/10.1073/pnas.2101084119 We found that the RFS stimulated 20.8 billion L (5.5 Bgal) of additional annual ethanol production, which requires nearly 1.3 billion bushels of corn after accounting for coproducts that can be fed to animals (46).
  4. https://pv-magazine-usa.com/2025/05/02/solar-grazing-supports-healthier-soil-food-for-sheep-study-finds/ Solar grazed sites tended to have higher soil organic matter than non-grazed sites, with values of 4.14% and 3.70% respectively. Soil pH was significantly higher in grazed sites, with an average of 6.20 compared to 5.81 in non-grazed sites, which the researchers said demonstrates the potential for solar grazing to improve solar site soil health.
  5. https://www.frontiersin.org/journals/sustainable-food-systems/articles/10.3389/fsufs.2025.1625483/full Despite a relatively short study period of three years for soil health and PCS parameters, and two years for forage quality parameters, significant benefits were seen. These benefits support the need for an ecosystem-based approach to vegetation management at solar sites. Grazed sites showed potential for improved soil indicators, such as higher organic matter, improved soil compaction, and stabilized erosion risks.
  6. https://farmland.org/blog/grazing-between-the-panels-how-sheep-are-expanding-whats-possible-for-solar-and-agriculture-in-massachusetts Researchers documented higher soil organic matter and active carbon in grazed solar sites, indicators of stronger soil biological activity. Jesse and Elspeth see improved moisture retention and less compaction compared to mowed-only sites.
  7. https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2024EF005429 Despite the prevalence of solar grazing, there is very limited research on the sustainability impacts of these systems and best practices for successful management. This review synthesizes existing research specific to agrivoltaic grazing systems and relevant research from adjacent fields to identify key knowledge gaps and recommendations for future research directions.
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