It’s an early, drizzly September morning at Our Table Cooperative farm in Sherwood, just a short drive south from Portland. The blueberry fields are done for the season, and some of the sunflowers are beginning to wilt.
While the summer growing season is almost over, crews are busy at the farm planting a different kind of crop — solar. This doesn’t look like what most people imagine when they think of solar panels. The crew hoists up a large solar array on a crane, while one worker fastens the panels on a 15-foot-high steel beam.
It looks like a giant rectangular umbrella, and there are six of them. On one side, the panels will generate energy for the farm. But Narendra Varma, the co-op’s executive director, says there’s another key benefit — shade.
“And of course, one could just put up shade cloth, which would be a lot cheaper than fancy solar panels,” he says. “But the advantage here is that the shade is controllable.”
The last few years, summers in Oregon and across the Pacific Northwest have been erratic, with more frequent hot days. Our Table grows all sorts of produce, from raspberries to tomatoes, peppers and turnips. But it’s getting more challenging to grow some of the most heat-sensitive crops, like lettuce and other salad greens.
“The greens get bitter, they bolt, which means they put up flower stalks and then they’re inedible at that point,” Varma says. “Or they just use a ton of water and not really produce a lot because they’re heat stressed.”
This solar project will help with that. It’s aptly called the Lettuce Shine Solar Project. Farmers at the co-op will be able to plant leafy greens under the elevated panels. On the flip side, the panels will generate about 112,500 kWh a year — enough to power the on-farm grocery store and the freezers. And because they are mounted on a dual-axis motor, they can control whether they want to optimize the panels for energy or shade.
“We can move the panels in two dimensions, which allows us to essentially optimize either for power generation … or to say, ‘No we don’t really care that much about power right now because it’s a long summer day anyway,’” Varma says.
The concept of using solar and agriculture isn’t new, but in recent years it’s been gaining momentum. It’s called agrivoltaics. In Oregon and across the United States, it’s in an experimental stage.
“There’s a huge explosion of agrivoltaics projects both in the U.S. and around the world,” said Dan Orzech, the general manager of the Oregon Clean Power Cooperative, a group that helps to finance community solar projects. “And people are trying all sorts of different things with all sorts of different crops.”
The Clean Power Cooperative is partly funding and developing the Our Table solar project with a grant from Portland General Electric’s Renewable Development Fund.
In the U.S., agrivoltaics can look like pollinator habitats under solar panels or sheep grazing on the grass on a utility-scale solar farm. But a lot of this technology is in the early research stage, said Orzech. He said the Our Table project was inspired by the Oregon State University Solar Harvest project at OSU’s North Willamette Research and Extension Center in Aurora.
Orzech explains that making local, diverse farms less fossil fuel-dependent is one part of the Lettuce Shine project. “And then there’s another mitigation piece, which is resiliency,” he says.
The U.S. Environmental Protection Agency’s 2024 Climate Change Indicators report shows heat waves in and around large cities are more frequent and intense than they used to be. In Oregon, the length of the growing season has increased by 30 days since the late 19th century. A longer season might limit the types of crops that can be grown in a place, encourage invasive species or weed growth, or force farmers to use more water.
That can take a toll on farmers. In 2021, an unprecedented heat dome caused significant crop damage across the Pacific Northwest. Varma saw firsthand the effect it had on the farm.
“We lost over 50% of our blueberry crop overnight,” Varma says. “So, something like that we say, ‘Oh, it’s only a one-in-50-year event,’ or something like that. But then with climate change, maybe it’s a one-in-10-year event. Well, you can’t afford that kind of loss every 10 years.”
Varma says that pushed the farm to adopt more climate-resilient farming practices, like using no-till methods, which can improve soil health, lower water usage and keep more carbon in the soil. And solar is one more step toward resilience.
Not everyone sees it that way. Some groups argue that large, utility-scale solar farms are not appropriate on nutrient-rich soils like in the Willamette Valley. Others simply don’t like how these projects look. Varma says he acknowledges that.
“A lot of times people are very opposed to seeing large solar farms, and I understand why. Sometimes they can be an eyesore,” he says. “But I think it’s important for people to kind of look at these things and go like, ‘This is the future. This is beautiful. I want to see more of this in my community because it makes me resilient.’”
Adam Ward, the chair at Oregon State University’s Department of Biological and Ecological Engineering, says solar panels in agriculture aren’t a silver bullet that will solve all the woes of climate change.
“It may not be appropriate on every field all the time for every crop or outcome,” Ward says. “But it should be one of those arrows in our quiver as we adapt to climate change.”
Like Orzech and Varma, Ward sees solar as one piece of the puzzle to adapt to climate change.
“When we plant in the shade, we are reducing stress on those plants, we’re reducing evapotranspiration,” Ward says. “So making water use more efficient.”
But he sees solar playing a more important role in the long term — one where farms are self-sustainable and off the grid, where tractors and other equipment do not rely on fossil-fuels, or where farms make their own fertilizer on-site.
“This is a very rapidly growing space and one that we hope benefits the environment and humans,” Ward says. “While we might find early traction as an adaptation strategy. We think in the long arc we see agrivoltaics as a sustainable way that we meet both our food and our energy needs for humanity.”
For Narendra Varma, the project is an experiment. He says it might not work as they think it will. But at the very least the electric bill will be lower.
“It’s either a win or a win-win,” he says. “Either way there’s a win in there.”
OPB’s “All Science. No Fiction.” featured Oregon State University agrivoltaics research in 2022.
Copyright 2024 Oregon Public Broadcasting
