Landowners with a passion for farming and an interest in solar energy with its consistent stream of revenue can satisfy both with agrivoltaics. By integrating photovoltaic (PV) systems above crops and pastures, agrivoltaics produces food and energy from the same plot, helping farmers increase their economic viability while reinvigorating their land.
Naturally Regenerating the Land
Intensive monocrop farming depletes the land of the nutrients needed to grow crops, steadily reducing the land’s productivity over the years. To improve soil structure and fertility, farmers rely on costly soil science and harsh herbicides and pesticides that impact their bottom line, the quality of the groundwater, and the vitality of the farmland.
With agrivoltaics, farmers can reinvigorate their least productive land by grazing livestock on it, which improves the soil structure, soil fertility, weed control, and biodiversity while deriving a steady stream of cash from solar energy.
Sheep are well-suited for grazing a solar farm. As small-bodied livestock, sheep have less impact on the soil than larger ruminants like cattle. They are easier to handle, and they can easily clear vegetation around photovoltaic mounting infrastructure. Through grazing, sheep can help manage weeds and insects, reducing the need for chemical herbicides and pesticides. They also decrease the need for tillage, which promotes erosion by exposing upper layers of soil to the wind.[1]
Containing many nutrients that are returned to the soil by microorganisms, sheep manure can contribute up to 35 percent of soil organic matter, providing vital nutrients to crops and supporting soil organisms that keep the soil healthy.[2]
Integrating Solar with Crops
For 10- to 50-acre photovoltaic installations, crop production may be an alternative to ranching livestock.
Because of the increased shade created by the PV modules, some crops may be well suited to agrivoltaic sites. Growing these crops in the shade means they require less water, which typically evaporates rapidly when irrigating an open field. Plant transpiration, the process by which plants move water to their leaves to cool themselves, can also cool overhead solar panels, boosting their efficiency.
Crops that could be well suited to agrivoltaic sites include those that are typically grown and harvested by hand or with small machinery like shade-loving pollinator crops, bedding plants, nursery crops, and smaller fruit trees or shrubs.
Early research at the University of Arizona has found that some plants, like cilantro, peppers, and tomatoes, grow just as well, if not better, under solar panels than in the open, while requiring only half the water.[3] To collect more light, the leaves of these plants, like basil, grow larger than they would if planted in an open field. This physiological response to shade might increase crop yields. Plants that naturally grow in tree shade, like the capsicum annuum pepper and tomatoes, may produce more fruit in an agrivoltaic system than they do in a field, most likely because they are less stressed by the constant sunlight. This research found that tomato production doubled, with 65 percent more water efficiency, and chili production tripled.
Interestingly, the research found that solar panels in an agrivoltaic setting produced three percent more energy during the May-June growing season and one percent more overall.[4]
Adapting and Creating Agrivoltaic Sites
While existing solar installations can be adapted for agrivoltaics, the future of the application is a highly integrated approach that accommodates the needs of both disciplines—farming and solar energy production. This means that solar installations will be designed to enhance crops or livestock, with agriculture helping to restore the land while cooling the PV arrays and maintaining vegetation.
Agrivoltaics is uniquely positioned to help farmers by injecting needed cash into their operation while helping remediate their land without the need for expensive chemicals.
Next Steps
If you are a landowner interested in introducing solar farming onto your property, contact us for a free site suitability assessment. If your land is suitable, we may extend an offer to lease or purchase your ground for solar development.
Making a switch or diversifying your energy sources with a solar energy system can be a safe, financially smart, and profitable decision in the longer term. If going solar is something that sounds right for your business, there are many things to consider. We can help you make sense of the entire picture.
To learn if solar is the right move for your organization, contact us for a free solar feasibility report.
[1] https://www.thefencepost.com/news/researchers-examine-benefits-of-sheep-grazing-in-vegetable-farming/
[2] https://www.agricology.co.uk/resources/benefits-sheep-arable-rotations
[3] https://www.wired.com/story/growing-crops-under-solar-panels-now-theres-a-bright-idea/
[4] https://www.barrongafford.org/uploads/2/9/2/2/29222307/barron-gafford_et_al_nature_sustainability_2019.pdf