Can solar panels installed on agricultural fields help us adapt and fight climate change at the same time? This is what a new study which will begin next month will explore.

“This study is about agriculture and climate change and how we can create sort of a win-win situation,” said Susan Phillips, director of the Robert Redford Conservancy at Pitzer College, who is leading the study. study.

The concept is called “agrivoltaic”, a combination of the words “agriculture” and “photovoltaics” – the process of converting light into electricity.

There are many ways to do agrivoltaics, but the basic idea is that instead of stopping agriculture to make way for solar power, elevated solar panels are installed above crops or livestock operations so that power generation and agriculture can happen at the same time, and potentially benefit everyone. other.

Different types of agrivoltaics

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Courtesy of the National Renewable Energy Laboratory

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While agrivoltaics has been studied in other areas of California, this will be the first study to see how it might work in Southern California. Agrivoltaics has seen success in parts of Europe, China as well as the United States, but it’s not happening much here in California…at least not yet.

How will the study take place?

The study will take place on a quarter of an acre of land Spadra Farm at Cal Poly Pomona. Researchers will study the behavior of a plot of romaine lettuce grown under panels compared to a plot that is not, over a period of three years. They will also have a mobile battery to store solar energy.

They will measure things like soil fungi and bacteria, plant nutrients, crop yield, water usage, temperature and much more.

“All of this is going to be very relevant to the production of a crop in Southern California, primarily romaine lettuce, which is in demand year-round,” said Rose Olivas, one of the project leaders.

A key question they are trying to answer is how much panel shade can reduce water use and improve plant and soil health. hotter summers due to climate change.

“We are living in a time of climate crisis and our growing seasons are increasingly limited, especially for cold-weather crops like romaine lettuce,” said Emily Kuhn, who will run the farm during the study. “So part of the goal of this project is to be able to produce crops like romaine lettuce for longer periods of time in the summer because it stretches out longer.”

They will begin installing the solar panels in December and are expected to begin planting in January.

What is the advantage?

Agrivoltaics already exists, mainly in Europe and China. Research worldwide and in parts of the United States has already found that the strategy can help reduce water consumption, improve soil health and increase crop yields. It can work with livestock grazing, a variety of crops as well as cover crops that provide habitat for native pollinators. Most agrivoltaic systems in the United States are currently on the East Coast and upper Midwest.

The benefits largely result from the shade provided by the panels. In increasingly extreme heat, panel shade can cool plants and livestock, contributing to soil health, water retention and crop yield. Shade can also help alleviate heat illnesses among farmworkers. And the plants under the panels can cool the solar panels themselves, making them more productive.

At the same time, as water supplies decline due to climate change and overexploitation, farmers are already, and will need to continue, removing much land from production. The American Farmland Trust, partner of this study, estimates 83% of new solar developments built in the coming decades will likely be on agricultural land.

So adding solar generation to the mix can help keep more land in production while potentially increasing yields with less water to circulate. Farms can benefit financially by saving on their energy bills or selling the electricity they produce back to the grid, if the transmission infrastructure is in place and their solar array is large enough for it is economical.

Phillips said she also sees agrivoltaics as a way to improve local economies.

“We need to diversify our economy in places like the Inland Empire, and we need to think about what it means to try to maintain the farmland we have,” Phillips said. “Combining this with energy production is a really interesting solution. »

Not a miracle solution

Agrivoltaics is a promising piece of the puzzle when it comes to addressing our energy needs, climate pollution and the many challenges farmers face, but it is not a silver bullet.

These projects are generally more expensive than traditional solar panels, technically difficult to design and difficult to permit, and they are not easy to scale, said Jon Reiter, a farmer and solar developer in the San Joaquin Valley. He believes that agrivoltaics are limited in California.

The Current State of Agrivoltaics in the United States Most systems focus on pollinators and other native habitats.

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National Renewable Energy Laboratory

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LAist

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“We’re not short of land, we’re short of water,” Reiter said. “If you raise the panels, it will increase the cost of additional steel…the net result is that electricity costs will be higher.” »

He said he thinks agrivoltaics would be more realistic than cover crops that serve pollinators, as well as in more urban areas or areas that don’t have as much space for solar and l agriculture (as in Massachusetts, which leads agrivoltaic efforts in the United States). University of California researchersas well as the National Renewable Energy Laboratory of the Ministry of Energy, working on the challenge of cost and scalability.

Reiter said the agrivoltaic route will depend on the specifics of each farm. He grows almonds, pistachios, raisins and blueberries. He said that even with crops like blueberries, where he could theoretically use agrivoltaics, it doesn’t make sense because he now harvests primarily by machine.

“Labor costs in California are so high that hand harvesting is at risk because it becomes unaffordable,” Reiter said. “I grow blueberries and we used to pick them by hand, but now we harvest them 100% by machine.”

Spacing out the panels to make room for these machines would not be cost-effective, he said.

When it comes to meeting clean energy needs, Reiter said California has the space to do so and developing more large-scale solar power on already disturbed farmland can help reduce development solar energy in sensitive desert habitats.

Ultimately, solar energy and agriculture don’t have to be at odds, Reiter said, but like any climate solution, there is no one-size-fits-all approach.