Tag Archive for: Agrivoltaics

Win for America’s Farmers: Harvesting Solar Energy 

“America’s solar industry has boomed in recent years, and is slated for a big boost from the Democrats’ recently passed climate bill. Yet solar still only accounts for about 3 percent of electricity flowing into America’s grid—less than one-seventh the share from coal. If we want to phase out fossil fuels and accommodate an electric vehicle revolution, the sun’s contribution has to rise dramatically—and fast. But where to put all the panles?

The best places for solar installations, according to a 2019 study from the University of Utah and Oregon State, tend to be the areas where we already grow our food. That’s because, just like sun-loving tomato plants that fare poorly when the mercury creeps north of 85 °F, photovoltaic (PV) panels lose their efficiency at higher temperatures. But that doesn’t mean we have to starve ourselves to keep lights on and cars humming. By elevating solar panels far enough above the ground so people, plants, and animals can operate underneath, we can “essentially harvest the sun twice,” says University of Arizona researcher Greg Barron-Gafford. Enough sunlight to grow crops gets past the panels, which also act as a shield against extreme heat, drought, and storms.” – Mother Jones  

5 Signs the US Agrisolar Revolution has Begun  

“An upswell of opposition to large-scale solar power plants on farms took shape in the U.S. last spring, partly fueled by conspiracy theories about climate change. Nevertheless, farmland is attractive to solar developers. Now they have a new support system on their side, in the form of agrivoltaics.” – Triplepundit.com  

Solar Energy Corporation of India Issues Tender to Install Agrisolar Pumps 

“New Delhi: The Solar Energy Corporation of India (SECI) on Monday issued a tender for setting up agricultural solar pumps in selected states pan-India under component-B of the PM-KUSUM scheme of the renewable energy ministry.  

‘Individual farmers will be supported to install standalone solar agriculture pumps of capacity up to 7.5 HP for replacement of existing diesel agriculture pumps and irrigation systems in off-grid areas, where grid supply is not available. Installation of new pumps will be permitted under this scheme except in dark zone areas,’ said the SECI tender document.” – Energyworld.com 

UC Davis Study Shows Harvesting Various Light Spectra Benefits Agrisolar  

“Scientists from the University of California, Davis, are investigating how to better harvest the sun — and its optimal light spectrum — to make agrivoltaic systems more efficient in arid agricultural regions like California. 

Their study, published in Earth’s Future, a journal of the American Geophysical Union, found that the red part of the light spectrum is more efficient for growing plants, while the blue part of the spectrum is better used for solar production.” UCDavis.com 

Massachusetts Sees Increase in Agrisolar Incentives 

“A Massachusetts incentive program for projects that blend solar energy and agricultural production shows signs of finally gaining momentum after a slow rollout that has at times frustrated solar developers and farmers alike. 

In 2018, Massachusetts became the first state to offer financial incentives for “dual-use” or “agrivoltaic” solar projects built above active agricultural land. Since the launch, however, just three projects have gotten up and running. Another eight have qualified for the incentive but not yet been built.” – Energynews.com  

In this study, a donor:acceptor polymer blend is optimized for its use in laminated devices while matching the optical needs of crops. The study reveals degradation modes undetectable under laboratory conditions such as module delamination, which accounts for 10–20% loss in active area. Among the active layers tested, polymer:fullerene blends are the most stable and position as robust light harvesters in future building-integrated organic photovoltaic systems.

In this article, researchers evaluated seasonal patterns of soil moisture (SM) and diurnal variation in incident sunlight (photosynthetic photon flux density [PPFD]) in a single-axis-tracking agrivoltaic system established in a formerly managed semiarid C3 grassland in Colorado. Their goals were to (1) quantify dynamic patterns of PPFD and SM within a 1.2 MW photovoltaic array in a perennial grassland, and (2) determine how aboveground net primary production (ANPP) and photosynthetic parameters responded to the resource patterns created by the photovoltaic array. Investigators found relatively weak relationships between SM and ANPP despite significant spatial variability in both. Further, there was little evidence that light-saturated photosynthesis and quantum yield of CO2 assimilation differed for plants growing directly beneath (lowest PPFD) versus between (highest PPFD) PV panels. Overall, the AV system established in this semiarid managed grassland did not alter patterns of ANPP in ways predictable from past studies of controls of ANPP in open grasslands.

In this article, researchers in Korea analyze the profitability of agrivoltaics and its implications for rural sustainability. The profitability of agrivoltaics is verified in all studied regions, and the order of profitability and productivity by region are opposite to each other. Researchers suggest that regions with lower productivity may have a higher preference for installing agrivoltaics, implying the installation of agrivoltaics provides a new incentive to continue farming even in regions with low agricultural productivity.

This resource aims to guide informed decisions by landowners, investors, planners, and government officials in considering the planning and siting of grid-scale solar systems in Pennsylvania. The intent is to balance and promote the goals of sustainable income-generation and protection of water, soil, and valuable agricultural land resources.

This study focused on the photosynthetic photon flux density and employed an all-climate solar spectrum model to calculate the photosynthetic photon flux density accurately on farmland partially shaded by solar panels and supporting tubes. The researchers also described an algorithm for estimating the photosynthetic photon flux density values under solar panels, which were then validated using photosynthetic photon flux density sensors. The calculation formula enables farmers to evaluate the economic efficiency of a system before introducing it.

This life cycle assessment study investigates the environmental performance of sheep-based agrivoltaic systems and concludes that agrivoltaic systems are superior to conventional ground-mounted PV systems because they have dual purposes and reduce the environmental impacts associated with producing food and electricity.

Researchers analyzed and compared the costs for an agrivoltaic system with the cost of plastic covers for blueberry crops in Chile. They also introduce a metric to calculate the price for covering cropland with an agrivoltaic system.

The purpose of this paper is to systematically synthesize the potential ecosystem services of agrivoltaics and summarize how these development strategies could address several United Nations Sustainable Development Goals. Led by Agrisolar Clearinghouse partner Leroy Walston, researchers focused on four broad potential ecosystem services of agrivoltaics: (1) energy and economic benefits; (2) agricultural provisioning services of food production and animal husbandry; (3) biodiversity conservation; and (4) regulating ecosystem services such ascarbon sequestration and water and soil conservation.

Written By: Alex Delworth, Clean Energy Policy Associate; Center for Rural Affairs

Just off the campus of Maharishi University in Fairfield Iowa, sits a 1.1-megawatt (MW) solar farm. Beneath the panels, a flock of sheep and their newborn lambs are grazing, while beginning rancher Emily Mauntel and her Australian Shepherd Ziggy stand back and admire their work.

Solar farms pose a considerable opportunity for multipurpose agricultural uses in rural spaces. Iowa has seen a rapid increase in solar project development the past two years. According to the Solar Energy Industries Association, the industry is expected to add another 1,304 MW—a 250% increase over current installed capacity—during the next five years. Depending on the type of technology installed, this could mean between 6,520 and 13,040 acres of land will be used for solar production. With proper local siting, these projects will be required to plant and maintain native vegetation underneath the panels. This increase in open pasture presents a unique opportunity to combine traditional land uses with renewable energy development, such as pollinator habitats or open grazing for livestock. An opportunity Emily has already begun benefiting from.

Originally from Michigan, Emily relocated to Fairfield to attend Maharishi International University. While completing a three-month internship at a goat farm in Oregon as part of the university’s Regenerative Organic Agriculture certificate program, her interest in livestock grew. After the internship, she remained in Oregon for another year, working for various livestock operations and gaining experience in the industry. In late 2021, she moved back to Fairfield to work on the university’s vegetable farm and help her peers in their respective livestock businesses.

Emily Mauntel holding a solar-grazing lamb. Photo: Emily Mauntel

One day she and a friend were driving past a large solar array in Minnesota and noticed how the infrastructure was perfect for sheep grazing. They knew about the array in Fairfield, which is owned by the university and operated by Ideal Energy, a local solar company. She contacted the solar company to pitch the idea first and gained their approval before approaching the university. Both parties were ecstatic because the university had been looking for somebody to graze livestock and Ideal Energy saw an opportunity to avoid spending about $5,000 for annual landscaping, according to the company. Emily said the two parties came to an agreement that she would graze the array, which provided her an opportunity to access pasture in exchange for landscaping the solar farm. With this agreement, Emily benefited by not having lease payments for the time her sheep were on the farm, saving her approximately $360 per month according to Iowa State University’s land lease estimates, or about $2,520 for 2022.

Sheep grazing under solar array. Photo: Emily Mauntel

Once Emily had approval, she and her friend went into business together and purchased a 30-head herd of sheep from an auction in Texas. In May 2022, 29 ewes and one ram were dropped off on the six-acre, 1.1-MW solar farm. Before purchasing the herd, she surveyed the land and determined that, given the amount of growth on the site, she would be able to graze five sheep per acre. That is two more than usual because of how lush the plant life was on the property. The site was planted with a mix of flowering prairie species, including clover, fescue, broad-leaf plantain, and others, which served as a good food source. The sheep were allowed to roam freely throughout the solar array, something Emily said worked well. Overall, she believes rotational grazing would have been more efficient but would have required a larger investment due to the cost of a moveable fence.

Emily with her herd. Photo: Emily Mauntel

What makes this story especially interesting is that the agribusiness model directly addresses two major issues beginning farmers face—access to land and infrastructure. A 2017 survey by the National Young Farmers Coalition found that land access was the number one issue their respondents faced. Young farmers, according to the survey, are also the most inclined to rent, which makes finding land with the right infrastructure more difficult.

The Fairfield solar site’s infrastructure made the land even more attractive to Emily. She said it had sufficient fencing to hold her sheep and keep out predators. Due to the required native vegetation management, it also had plenty of food for the sheep, which means she never had to supplement food for them, except a mineral feed mix for nutrition. A water source to fill up the livestock troughs and an access road straight up to the gate also proved beneficial. Considering all of these factors, Emily was able to cut a lot of costs throughout the process.

Newly energized by the experience she has gained through solar grazers and managing her own livestock, Emily is now looking to return to the West to continue ranching. She and her business partner plan to sell their herd. Emily hopes to see the solar grazing model continue on the site, saying it has been a perfect opportunity for her to gain experience in the industry, and she believes it will be a great opportunity for the next person, as well.