Agrivoltaics, also known as agrophotovoltaics (APV), is co-developing the same area of land for both solar photovoltaic power as well as for agriculture. This technique was originally conceived by Adolf Goetzberger and Armin Zastrow in 1981. In 1981, Adolf Goetzberger and Armin Zastrow were the first to propose the concept of dual-use of arable land for solar energy production and plant cultivation to improve overall production. They were addressing the ongoing discussion on the competition for the use of arable land between solar energy production and crop. The light saturation point is the maximum number of photons absorbable by a plant species. As more photons will not increase the rate of photosynthesis, Akira Nagashima suggests combining PV systems and farming to use the excess light. He developed the first prototypes in Japan in 2004.
The term “agrivoltaic“ was used for the first time in a publication in 2011. The concept is known under several names in the world: “agrophotovoltaics” in Germany, “agrovoltaics” in Italy, “solar sharing” in Asia. Facilities such as photovoltaic greenhouses can be considered as agrivoltaic systems.
“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,” says Greg Barron-Gafford, an associate professor in the School of Geography and Development at the University of Arizona
A research done by The French scientists Christophe Dupraz and his team indicates that agrivoltaic systems increase global land productivity from 35 to 73 percent!
The researchers of the Fraunhofer Institute for Solar Energy Systems studied the same topic to find out how solar radiation and food crops can be used. The examination took place near Lake Constance which borders Switzerland, Germany, and Austria. For one year the pilot project used 720 bi-facial solar modules which covered around 1/3 of a hectare. They mounted the panels high enough, so crops receive almost the same amount of sunlight as if they grow naturally.
Researchers discovered that land’s productivity could be raised by 60 percent. “The project results from the first year are a complete success: the agrophotovoltaic system proved suitable for the practice and costs as much as a small solar roof system. The crop production is sufficiently high and can be profitably sold on the market,” explains Stephan Schindele, project manager of agrophotovoltaics at Fraunhofer ISE to Digital Journal.
The examination proved that farming and PV can be compatible. It reduces competition for land and works efficiently too while providing additional income for farmers.
Another reason why farmers are moving to solar farming is the guaranteed financial gain. PV installation can work along with traditional farming and bring income even if nature’s conditions are incompatible with grown culture’s needs as discover by Fraunhofer Institute’s researches.
Definitely, agrophotovoltaic is a new way of using solar technology together with traditional farming. For sure, it still needs some discussions, testing, and further development, but it’s today’s method – solar farming – that could have big perspectives to benefit society and business more than it has ever been before.
Besides, the researchers also found that the agrivoltaics system increased the efficiency of energy production. Solar panels are inherently sensitive to temperature as they warm causing their efficiency to drop. Cultivating crops underneath the PV panels allowed researchers to reduce the temperature of the panels, thereby increasing their efficiency.
“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 says.
The agrivoltaic PV panels were cooler during daytime hours compared to the traditional panel array by approximately 9°C – 48°F-, allowing for better performance.
The co-location of PV and agriculture could offer win-win outcomes across many sectors, increasing crop production, reducing water loss, and improving the efficiency of PV arrays.
As Macknick notes, “The promising results of this work have broad implications for how solar development and farming across the globe could be integrated to provide mutual benefits.”
Written by: Laila El Azhary