Agrivoltaics — Use It Where It Works, Don’t Use It Where It Doesn’t – CleanTechnica

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Agrivoltaics is a fancy name for the combination of solar panels and farming. Growing food and raising farm animals are both about harvesting the energy of the sun. So are solar farms. In some cases, they can be combined to increase the total productivity of land, which benefits human society and puts more money in the pockets of farmers. In other cases, the synergy between solar and farming is less successful. The trick is knowing which is which. Several recent developments suggest there are more positive use cases for agrivoltaics than previously thought.

Germany’s Wirtschafts Woche (Business Week) has a report on agrivoltaics in Europe this week. It says agrivoltaics have the potential to resolve the land use conflict between the energy and agricultural sectors. According to a study by the Jülich Research Center, the potential in Germany is enormous. 5,437 gigawatts of solar power could be installed on German fields — 25 times more than the government’s target of 215 gigawatts of solar power by 2030.

The idea for agrivoltaics was born in the 1980s at the Fraunhofer ISE. On test fields — the first in Germany was built in 2004 — they have built various types of solar structures, in different directions, with different crops underneath. Solar panels mounted on stilts are being used to grow hops and fruits, including the grapes used to make wine. The solar panels take some of the light away from the plants but also provide shade in the summer and protect against hail.

Such systems are being used by cattle ranchers in Germany, where one system is producing 70 MW of power while cows roam underneath. The solar array keeps moisture in the earth below from evaporating as quickly as it normally would in the summer, which means the cows will have enough greenery to eat even on hot days.

Agrivoltaics can lead to more income for farmers. In a trial project in the Lake Constance region, the harvest declined by 20 percent and the output from the solar array was reduced by 17 percent compared to a conventional system. However, the combined output of both resulted in about a 50 percent increase in productivity of the land, according to a report by the Federal Agricultural Information Center.

That may be why the number of agrivoltaics projects is increasing. In Sicily, a 135 megawatt solar plant is being built that shares the area with olive and fig trees. In Austria, an agrivoltaics installation is providing 164 MW of power while chickpeas grow beneath the panels. While the levelized cost of electricity is higher for agrivoltaics versus conventional solar installations — primarily because the mounting systems are more expensive — that ignores the value of the farm products that result. When the value of those products is combined with the income from a solar installation, farmers earn more per acre with agrivoltaics.

Sheep & Agrivoltaics In Texas

What is a problem for some is an opportunity for others. Enel Energy has eight solar farms in Texas. Combined they cover more land area than Manhattan. A lot of vegetation grows under all those panels, vegetation that has to be mowed. Or you can turn a flock of sheep loose on those solar farms and let them eat all the grass and other plants. But where do you get the sheep? That’s where JR Howard comes in. He rents flocks of sheep to Enel Energy. He makes money, Enel saves money. Everybody’s happy.

“Ultimately, we’re a business,” Jesse Puckett, director of sustainability projects and community affairs at Enel told Canary Media. ​“This is one way that we can enhance the bottom line and build sustainability into our project.” The sheep are more efficient than lawnmowers because they can get into the nooks and crannies under the panels Puckett said, although some additional mowing is sometimes necessary. Howard’s company — Texas Solar Sheep — provides mowing services as well. Mowing is also more likely to kick up rocks or other debris, damaging panels that then must be repaired, adding to costs.

Agrivoltaics projects involving sheep have been shown to improve the quality of the soil, since their manure is a natural fertilizer. At a solar installation in Minnesota, where Enel first started grazing sheep in 2017, the company saw a 200 percent improvement in organic matter. Using sheep instead of mowers also cuts down on fossil fuel use, while allowing native plants to mature and bloom. Solar projects that prioritize native plant growth have been found to increase the biodiversity of plants and insects, like native bees, and to reduce soil erosion. The sheep benefit, too, because shade from the solar panels keep them cool. Howard has found the sheep don’t need as much water as when they graze on open fields.

The demand for sheep for solar farms has skyrocketed over the past few years as more and more large solar installations are being built. When he first started his business three years ago, Howard had just 400 sheep on one solar site. Since then, he’s deployed over 10,000. The increasing demand for sheep grazing on solar farms is ​“the greatest opportunity for the sheep industry in my lifetime,” Howard told Canary Media. Howard’s business is a form of agrivoltaics, which combines solar panels with agriculture or other land uses that benefit farmers and ecosystems.

Meeting America’s ambitious clean energy goals will require rapid installation of large-scale solar farms over the next few decades. While much of that solar will be built on rooftops and on contaminated land that can’t be used for anything else — like former nuclear sites — some of it will inevitably take up viable farmland. “It’s not possible to meet solar demand without using some farmland,” said Jordan Macknick, lead energy, water, and land analyst for the National Renewable Energy Laboratory. But the overall amount will probably be relatively small, he says. If every new solar project were built on agricultural land, 10 million acres at most would be needed to achieve a completely decarbonized electric grid by 2050 — less than 1 percent of all the country’s farmland.

Agrivoltaics does not replace farmland so much as it transforms the way that land is used. “I think we recognize the fact that, as an industry, we have this amazing opportunity to do things a little bit different,” Puckett said. In addition to grazing sheep, several of Enel’s sites will incorporate beekeeping, native plant habitat, and hay production. Across the US, there are already 500 agrivoltaics projects that cover about 62,000 acres of land.

Agrivoltaics promote more sustainable farming while harvesting clean energy from the sun. They make farming more profitable for farmers. Expect the technology to grow as more use cases are discovered. After all, a solar farm is a farm. Ultimately, all life on Earth is powered by sunlight. It is free, abundant, and produces no emissions. Combining farming and solar power may be the smartest idea since sliced bread — a win for farmers and a win for the environment. No wonder fossil fuel companies hate it!