Groundbreaking New Study Reveals Crops Thrive Under Solar Panels And That The Panels Produce More Energy
Exciting new research has just found that solar panels might actually help crops to thrive in arid areas.
Agrivoltaics, which is also known as “solar sharing,” is the idea that co-locating of agriculture and solar photovoltaic panels, and it has been gaining traction over the past few years. As agrivoltaics has gotten more popular, few studies have monitored all aspects of the associated food, energy, and water systems involved. On top of that, no research has focused on dryland areas, which are regions that experience food production challenges and water shortages, but have an overabundance of sun energy.
“Many of us want more renewable energy, but where do you put all of those panels? As solar installations grow, they tend to be out on the edges of cities, and this is historically where we have already been growing our food,” said Greg Barron-Gafford, an associate professor in the School of Geography and Development and lead author of the study.
Led by the University of Arizona, the research found that the current croplands are the “land covers with the greatest solar PV power potential” based on an extensive analysis of incoming sunlight, air temperature and relative humidity.
“So which land use do you prefer—food or energy production? This challenge strikes right at the intersection of human-environment connections, and that is where geographers shine!” said Barron-Gafford. “We started to ask, ‘Why not do produce both in the same place?’ And we have been growing crops like tomatoes, peppers, chard, kale, and herbs in the shade of solar panels ever since.”
The study focused on chiltepin pepper, jalapeno, and cherry tomato plants that were placed under PV panels. Researchers concluded that the agrivoltaics system significantly impacted three factors that affect plant growth and reproduction: air temperatures, direct sunlight and atmospheric demand for water. They discovered that the shade from the PV panels resulted in cooler daytime temperatures and warmer nighttime temperatures than the traditional, open-sky planting system.
“We found that many of our food crops do better in the shade of solar panels because they are spared from the direct sun,” Baron-Gafford said. “In fact, total chiltepin fruit production was three times greater under the PV panels in an agrivoltaic system, and tomato production was twice as great!”
“At the same time, we found that each irrigation event can support crop growth for days, not just hours, as in current agriculture practices. This finding suggests we could reduce our water use but still maintain levels of food production,” Barron-Gafford continued, explaining that soil moisture remained approximately 15% higher in the agrivoltaics system than the control plot when irrigating every other day.
Also, the team found that the agrivoltaics system increased the efficiency of energy production.
“Those overheating solar panels are actually cooled down by the fact that the crops underneath are emitting water through their natural process of transpiration—just like misters on the patio of your favorite restaurant,” Barron-Gafford said. “All told, that is a win-win-win in terms of bettering our how we grow our food, utilize our precious water resources, and produce renewable energy.”
The team of researchers has since teamed up with the U.S. Department of Energy’s National Renewable Energy Lab to figure out how well an agrivoltaics approach can work in other regions of the country and how regional policies can promote adoption of novel approaches to solve these pervasive problems.