In its 150-year history, Paul Knowlton’s farm in Grafton, Massachusetts has produced vegetables, dairy products and, more recently, hay. The evolution of farm use was based on changing markets and a variable climate. Recently, however, Mr. Knowlton added a new type of cash crop: solar power.
For Mr. Knowlton, a fifth-generation farmer and current owner, it was an easy decision. He had already installed solar panels to provide electricity for his house and barn. When a real estate agent knocked on the door to see if he was interested in leasing a small portion of his land to install a solar panel, “he planted the seed that I could do more,” Knowlton said.
Mr. Knowlton looked at several companies, but was most impressed with BlueWave Solar, a developer in Boston that focuses primarily on solar installations and battery storage, which allows excess electricity to be fed into the power grid. Soon, two small parcels of largely unused land were home to low-lying power-producing panels. This year, Mr. Knowlton’s farm is going one step further: on a third plot, solar panels will share space with crops so that both can thrive.
This approach is called agrivoltaics, a portmanteau of agriculture and voltaic cells, which transform solar energy into electrical energy. The technology, also called dual-use solar, involves adjusting the height of the solar panels up to 14 feet, as well as adjusting the spacing between them, to accommodate equipment, workers, crops and grazing animals. The spacing and angle of the panels allows light to reach the plants below and has the added benefit of protecting those crops from extreme heat.
The electricity generated is uploaded to the grid, usually through nearby substations. While some of the electricity may go to the host farm, the projects are designed to provide power for general use. And such solar installations provide an alternative source of income in the form of payments to landlords like Knowlton or a reduction in lease payments for tenant farmers.
BlueWave has primarily focused on designing the projects and then selling them to companies that build and oversee them. The Grafton project, on Mr. Knowlton’s estate, for example, is now owned by the energy company AES Corporation.
“Agrivoltaics not only further the clean energy imperative, but are critical to keeping farms running,” said John DeVillars, one of the three BlueWave co-founders and chairman of the board of directors.
Dual-use solar power sparked interest more than a decade ago because “big installations in the middle of nowhere won’t solve all of our energy problems — shipping that power can be very expensive,” said Greg Barron-Gafford, a biogeographer. and assistant professor at the University of Arizona. Farms in many parts of the country are in peri-urban areas, transition zones from rural to urban land. Its proximity to high-use metropolitan areas makes open farmland particularly well-suited for solar panels, but in the past, without any co-existing agriculture, such a location can lead to conflict over whether food production should prevail. or energy.
A study by the AgriSolar Clearhouse, a new collaboration to connect farmers and other landowners to agrivoltaic technology, also showed that installations encourage growth by protecting crops from rising temperatures and helping with conservation of the environment. Water. While the technology remains in its infancy in the United States compared to countries in Europe, where the technology has been in use for more than a decade, federal regulators as well as academics and developers are working to remedy that disparity.
Early results are promising, said Garrett Nilsen, acting director of the US Department of Energy’s Office of Solar Energy Technologies. “There’s a project in Arizona where they’ve seen a threefold increase in crop yields.” when under this type of system and up to a 50 percent reduction in irrigation requirements” because the panels provide shade, he said. In addition, the plants under the panels release water into the air, which cools the modules, creating what Mr. Nelson described as a “symbiotic relationship between the plants and the panels.”
The first BlueWave project to come online is a 10-acre farm in Rockport, Maine, now owned and operated by Navisun, a solar energy producer. Wild blueberry cultivars have been planted under the solar panels, which will produce 4.2 megawatts of power; The project is estimated to produce 5,468 kilowatt-hours per year, equivalent to the amount of energy needed for approximately 500 American homes.
Unlike Massachusetts, Maine doesn’t offer significant incentives for solar power use, so there was a 10 percent to 15 percent premium in costs compared to similar projects, which BlueWave absorbed, DeVillars said. (That practice is consistent with the company’s status as a B Corporation, which requires a commitment to social and environmental goals.)
Other players are clearly seeing the potential of agrivoltaics: On May 12, Axium Infrastructure, an investment management firm, announced the acquisition of BlueWave. Trevor Hardy will remain as CEO and Eric Graber-Lopez will continue as Chairman, while Mr. DeVillars will become Chairman Emeritus.
Mr. Hardy said the sale would allow BlueWave to expand to own and operate, not just develop, solar installations and battery storage. Ultimately, he said, the sale “puts us in a stronger place for dual use.”
“Farmers work for the long haul,” he continued. “It’s more convincing to drive down farm roads and sit down with the owners at the kitchen table and say that we developed, own and operate the facility.” And the potential of the technology goes far beyond blueberries; agricultural uses have included vineyards and shrimp farming.
BlueWave is not the only developer of agrivoltaics. According to the Germany-based Fraunhofer Institute for Solar Energy Systems ISE, five megawatts of energy were produced through these systems in 2012; by 2021, 14 gigawatts of power will be generated in dual-use systems, roughly equivalent to the electricity needed by about two million American homes a year, according to a spokeswoman for the Department of Energy’s office of technologies. And the technology is evolving rapidly; in the few years since installation on Mr Knowlton’s estate, adjustable panels have been developed that can be moved to maximize sunlight capture, for example.
“It’s not always worth being a pioneer and sometimes it’s very challenging,” said Mr. Hardy, who grew up in a farming family in South Africa. Finding suitable sites, where there is sufficient sun and proximity to a substation or other electrical infrastructure, can be difficult. Opposition from neighbors, especially where the panels are visible from other houses or even from the street, is not uncommon.
In fact, BlueWave was one of several defendants named in a lawsuit over a proposed plan for agrivoltaics in Northfield, Massachusetts. A state court recently ruled that the neighbor had the right to challenge the proposed development. One of the plaintiffs, Christopher Kalinowski, said that among his concerns was that his views would be obstructed and “the area would lose farmland.” (Mr. Hardy declined to comment on the litigation.)
Additionally, some chapters of the environmental nonprofit Audubon have spoken out about the technology’s potential effect on wildlife. Michelle Manion, vice president of policy and advocacy for Mass Audubon, said that while his organization supported renewable energy, including solar power within farming operations, “we want to maximize the placement of ground-mounted solar power on some of our land that is the least ecologically sensitive first.”
And there is a general concern that even with dual-use solar panels, arable land may be lost, though BlueWave says the land can be reverted to pure agricultural uses once solar leases expire, typically 20 to 30 years. .
But one of the most significant obstacles is cost. The skyrocketing cost of steel has a direct effect on agrivoltaics’ emphasis on raising panels 10 to 14 feet. “For every foot you go up, you have to sink two feet into the foundation,” explained Mr. Hardy. “It’s a challenging industry when you think about what we need to do to achieve climate goals. But we stay the course.”
Ultimately, however, it all depends on the taste of the crops: if the taste or even the appearance strays too far from that of traditional products, the technology will be a hard sell. But in an early study, researchers at the University of Arizona’s Biosphere 2 Agrivoltaics Learning Lab found that tasters preferred agrivoltaic-grown potatoes, basil and squash. The beans, however, can take some time: the small sample of tasters preferred the traditionally grown version.