What happens when sheep meet solar panels? A ‘beautiful symbiotic relationship.’

Agrivoltaics, or the practice of using land for both agriculture and renewable energy, is increasing in Massachusetts, making for some unexpected partnerships.

FITCHBURG — Leaning on the back of their pickup truck, farmers Jesse and Elspeth Robertson-Dubois kept a keen eye on their flock of sheep. As the sun beat down, the majority of the flock huddled together, sheltering from the heat under a row of silver solar panels closest to their buckets of water.

But further up the hill, almost out of sight amid the long array of panels, a sleepy lamb suddenly awoke to find its mother far away.

“Is the lamb lost over there?” Elspeth Robertson-Dubois asked, in response to its faint bleating. Before long, however, the lamb found its footing and trotted beneath the shade of the metallic panels until it was reunited with the flock.

More than 200 sheep grazed amid 15,000 solar panels at the Fitchburg Renewables solar farm. The sheep are owned by Finicky Farm, run by Jesse Robertson-Dubois and his daughter, Elspeth. The sheep eat the tall grass, weeds, and clover and keep them from blocking the panels.John Tlumacki/Globe Staff

Once an abandoned apple orchard, this land was converted roughly three years ago into a solar farm, with hundreds of panels spread across its 20 acres. The owner of the panels, solar company Nexamp, is leasing the land from the orchard owner for 25 years. Not long after launching the site, the company partnered with Finicky Farms, owned by the Robertson-Dubois family. In exchange for keeping the grasses low, the farmers are paid by the solar company and also get to use the land as a free grazing site for a flock of 215 sheep, which they process and sell locally as lamb.

For the sheep, the panels provide protection from heat, rain, and snow, with some sheep even using the base of the structure as a scratching post during shedding season. Meanwhile, Elspeth Robertson-Dubois said, the flock’s steady consumption of forage on the land prevents the grassy plants from growing high enough to block sunlight from reaching the panels, maintaining the productivity of the array. As they graze, the sheep also improve soil health, a benefit for plant biodiversity and animals that feed there.

A decade ago, grazing sheep on land intended for solar panels was a mere pipe dream for Massachusetts farmers and environmentalists alike. But in 2018, the state made a big push for solar with its financial incentive program, SMART, or Solar Massachusetts Renewable Target, which requires utility companies to support the development of smaller solar projects. The increase of solar panels closer to the ground, instead of on the roofs of buildings, has produced what Elspeth Robertson-Dubois called a “beautiful symbiotic relationship” between agriculture and renewable energy, doubling the usefulness of a single plot of land.

This shared land use between agriculture and solar power is known as agrivoltaics. There are at least 45 solar operations in Massachusetts sharing the land with farmers, according to the state’s Department of Energy Resources. Of those, seven currently benefit from the SMART program, making Massachusetts the first state to offer financial incentives for agrivoltaics. And, according to the energy department, an additional 14 sites using that program are on the way.

While grazing around solar panels is among the more common examples, growing crops such as beets and carrots in the shade of solar panels has also increased in popularity over the past decade. Finicky Farms is currently one of only a handful of grazing operations in Massachusetts that make use of the land under solar panels, but the industry is expanding throughout New England.

“If we’re not grazing, we’re hiring lawn mower teams to come in,” said Keith Hevenor, communications manager for Nexamp Solar. “Number one, they’re burning fossil fuels to mow the grass on a clean energy site, which is kind of antisolar.”

And with mowers, “it’s somewhat risky: you come in here with a lawnmower and start kicking up rocks around solar panels [or] bump into something,” Hevenor added. “The sheep are a lot lower impact, a lot safer, and definitely a more sustainable way to manage the vegetation for us.”

The solar company is also starting to experiment with pigs at one of its sites in upstate New York, and Hevenor said the only livestock they won’t work with is goats: “Goats love to climb, and they eat everything” — including wires, cords, and fences, he said.

A sheep ate a piece of rye grass under a solar panel. John Tlumacki/Globe Staff

“We actually have a goat herd,” Elspeth Roberston-Dubois said, “but we don’t graze in this type of array because they would have a joy trying to jump on the panels!” She added that grazing with goats is possible in tilted arrays, or groups of panels, which have solar panels that move with the sun, positioned much higher off the ground.

The country’s oldest solar farm was launched in California in the 1980s, and it would take several decades for the technology to blossom into the major renewable energy industry it is today. However, even as acres of solar panels became more commonplace in the 21st century, for much of the 2010s, the practice of sharing the land with livestock was rare, occurring only “in little fits and starts around the country,” according to Daniel Finnegan, a board member of the American Solar Grazing Association and owner of Solar Shepherd, one of the earliest Massachusetts-based solar grazing operations.

When Finnegan joined the association as a founding member in 2018, there were less than a dozen members. This year, he said, membership has grown to roughly 800 nationally.

“The real eruption, this modern take on solar grazing, started in 2018,” Finnegan explained. “It really began along the Mass. Pike in the Greater Worcester area all the way out to the Finger Lakes.”

Jesse Robertson-Dubois, who started solar grazing with his daughter Elspeth in 2021, witnessed the rise in solar in Central Massachusetts firsthand and quickly became eager to get involved.

“We switched from managing a farm in Western Mass. to managing a farm in Eastern Mass. I had a year where I was driving back and forth, going up and down the pike by all those solar arrays ... and I was like, ‘Something’s happening here that could work!’” he said, recalling the many times he pulled his truck over to a solar array to peer through the wire fence at the acres of wispy grass cropping up beneath the panels. He now rotates his sheep among 10 solar sites across Massachusetts.

On any given day, according to Hevenor, the Fitchburg site alone produces 5 megawatts of electricity, enough to power roughly 800 average-sized residential homes.

Dorothy McGlincy, environmental scientist and executive director of the Massachusetts Association of Conservation Commissions, said that while conservationists most strongly support the increase of solar on homes, parking lots, and other buildings, there are situations, such as on land with poor soil quality or few crops, where putting solar panels in open green space make sense.

The association “supports development of clean energy projects on land that will not impact prime farmland, reduce food production capacity, impact wetland resources, or negatively impact open space,” she said.

Although, because of its size, Massachusetts solar grazing sites trend smaller than other states (Finnegan said solar farms here tend to be closer to a dozen acres, rather than a few hundred), he expects the industry to continue blooming in the coming years.

“The reason solar companies go for this is because they’re seeing the improvement in soil health and seeing that this is a better, smarter way to use this land,” he said. “Massachusetts, while we were one of the first, we’ve only just started to scratch the surface.”