Agrivoltaics Advancing

Solar panels on Paul Knowlton’s farm in Grafton, Mass. Cattle will graze below the panels, which rise to 14 feet above the ground. Tony Cenicola/The New York Times

The concept of agrivoltaics has been an occasional topic in our pages over the years, most recently as we have prepared to plant thousands of coffee saplings. Ellen Rosen focuses our attention on how the advances in technology, and entrepreneurship in this space, are addressing the challenges:

Can Dual-Use Solar Panels Provide Power and Share Space With Crops?

Companies like BlueWave are betting on it. But the technology has its critics.

Mr. Knowlton preparing the soil between the panels before he plants butternut squash and lettuce. Tony Cenicola/The New York Times

In its 150-year history, Paul Knowlton’s farm in Grafton, Mass., has produced vegetables, dairy products and, most recently, hay. The evolution of the farm’s use turned 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 the current owner, it was an easy call. He had already installed solar panels to provide electricity for his home and barn. When a real estate agent came knocking to see if he was interested in leasing a small portion of his land for a solar array, “she planted the seed that I could do more,” Mr. 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 to the power grid. Soon, two small parcels of largely unused land were home to low-to-the-ground panels that produce power. This year, Mr. Knowlton’s farm will go one step further: In a third parcel, 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 power to electrical power. Also called dual-use solar, the technology involves adjusting the height of solar panels to as much as 14 feet, as well as adjusting the spacing between them, to accommodate equipment, workers, crops and grazing animals. The spacing and the angle of the panels allows light to reach the plants below, and has the added benefit of shielding those crops from extreme heat.

The electricity generated gets uploaded to the grid, typically through nearby substations. While some of the electricity may find its way to the host farm, the projects are devised to provide power for general use. And such solar installations provide an alternative source of revenue in the form of payments to landowners like Mr. Knowlton or a reduction in lease payments for tenant farmers.