In the years to come, the world will need more clean energy and more food.
Unfortunately, those needs are sometimes in conflict. One example: the creation of large solar farms that take farmland out of production.
But what if solar power production could be developed in ways that coexist with existing farms, orchards and ranches? A new state-funded report, co-authored by Washington State University researchers, evaluates the feasibility of such an approach, known as "agrivoltaics." Researchers found that it could work across tens of thousands of acres of Washington farmland - producing power, offering shade to protect certain crops and livestock, and keeping agricultural land in operation.
"Pulling land out of food production is not something we should be doing," said Chad Kruger, the director of WSU's Center for Sustaining Agriculture & Natural Resources and assistant director for WSU's Institute for Northwest Energy Futures, who co-authored the report. "How can we potentially integrate energy generation and food production in a way that isn't a proposition where one side wins and the other loses - where it really is a dual benefit?"
More study is required, and significant obstacles remain, including a high-upfront cost. But the report - titled "Low-hanging fruit for Washington's energy future?" - concludes that there is reason for "cautious optimism" about implementing agrivoltaics in the state. In addition to preserving farmland, the approach would help prevent the conversion of undeveloped natural areas, like shrubsteppe and Palouse prairie, into single-use solar projects.
The project involved reviewing scientific literature, mapping agricultural land where agrivolataics might work, and surveying farmers. It lays out a series of recommendations for advancing the technology, including establishing demonstration projects, providing more information to farmers, and creating policy and financial incentives.
The report estimates that agrivoltaics could work on 87,000 acres of agricultural land in Washington state that are within one mile of an electrical substation. It is particularly promising for apples, berries and other perennial fruiting crops; half the land identified as feasible was orchards, primarily in central and eastern parts of the state. Dairy farms may also be a good fit.
That acreage could produce between 8.7 and 17.4 gigawatts of power; that would go a long way toward meeting estimates that Washington needs to produce 20 gigawatts of solar power to meet state-mandated clean-energy goals.
Agrivoltaics has been applied in limited places around the world, including Japan and Europe, but no such project is currently operating in Washington. Kruger is working to establish a pilot project at the WSU Sunrise Research Orchard near Wenatchee. The project has been designed, and Kruger is pursuing funding sources for construction.
Such a project could go a long way in demonstrating the approach to wary farmers.
The report estimates that agrivoltaics could work on 87,000 acres of agricultural land in Washington state that are within one mile of an electrical substation.
"That's the thing we heard repeatedly from the farmers: They're excited by the idea and they want to see someone else do it first," said Max Lambert, Washington's director of science for The Nature Conservancy and lead author of the report. "One thing we learned from the survey was farmers deeply, deeply trust WSU and they trust the conservation commission and conservation districts here in Washington. We have good science suggesting this should work well, but actually seeing it happen on the ground would be that enabling condition to get them going."
Other partners involved in the report were the American Farmland Trust, which conducted surveys of farmers, and the University of California, Santa Barbara.
The approach would not work well on all farms. Crops that rely on large equipment for harvesting would not be well-suited for adding solar panels. But apples and some other fruits could work well - solar panels could be installed in ways that don't impede harvest or other field activities, and they would be particularly beneficial in preventing sunburn.
Apple growers now battle sunburn with netting or evaporative cooling systems. Solar panels above the trees could provide shading that gives growers control over how and when the shade is applied, while providing power or additional income from power generation.
There may be additional synergies. For instance, not only do solar panels provide shade protection to fruit, but the solar infrastructure could reduce irrigation costs and replace the cost of trellising, shade cloth itself, and installing and removing shade cloth seasonally.
One hundred farmers were surveyed for the report; most knew little about the technology and were not willing to alter their crop types to accommodate solar infrastructure. Still, more than half of respondents expressed moderate to strong interest in the technology.
The project also offered an opportunity for an undergraduate at WSU to gain valuable research experience. Karina Schoenbachler, a senior studying agricultural economics, said her internship gave her valuable experience in assessing scientific literature, as well as introducing her to people involved in key issues facing Washington state.
"They definitely made it easy for me to do the research the way I wanted to and to make the experience what I wanted," said Schoenbachler, who grew up on cattle ranch in Western Washington. "I just thought it was great to work with people who are working to not only better the state and the understanding of agrivoltaics, but also my education, experience and future career."
