One of the most debated topics within the #solar #energy community revolves around where the best locations on earth are to place #solar panels. Researchers have constructed solar panels in parking lots, placed solar panels on roadways, and desert solar farms have even been tested and funded in certain parts of the world, including the Desert Sunlight Solar Farm in California.
A recent study directly related to the best regions for solar panel function was released by the #Oregon State University College of #Agricultural Sciences earlier this month. Researchers in the study aimed to discover which climate, temperature, and weather conditions benefit solar panel production the most.
#Agrivoltaics: The Best of Both Worlds
According to Elnaz Adeh and Chad Higgins, two of the primary researchers of the OSU solar panel study, the best places on Earth to place solar panels are on farmlands. Co-developing certain areas for both agricultural purposes and solar panel production is not a new concept. The term agrivoltaics has been around since the early 1980s and is a technique that uses one area of land for two purposes – one being agricultural and the other solar power.
In addition to confirmation that farmlands are the best regions for solar panel efficiency, the study also found that if less 1% of agricultural land across the world were to share space with solar panels, this would be sufficient enough to meet global energy demands.
Solar panel efficiency and overall energy output are greatly impacted by four environmental variables including wind speed, humidity, temperature, and overall sun exposure. These four factors were tested using the 35th Street Solar Array in Corvallis, Oregon, which has been located on the west side of the OSU campus since 2013.
After analyzing data collected throughout the solar panel study, along with collaborative assistance from Tesla, OSU researchers stumbled upon the key to efficient solar panel production. According to Higgins, their research shows that solar panels have preferences that emulate those of humans – they function best in cool, breezy, and dry environments.
Higgins stated in an interview with OSU that solar panel efficiency actually decreases when weather conditions are hot, humid, and lack airflow. Therefore, areas like western America, the Middle East, and southern Africa are slated to be the top regions for solar panel efficiency. The results of this study corroborate findings previously discovered in Agrivoltaic research.
Agrivoltaics is a Win-Win
Back in November of 2018, Adeh and Higgens tested crop yield output on fields that had solar panels placed on them. At the 35th Street Solar Array, microclimate research stations were utilized to record the air temperature, humidity, soil moisture, as well as wind speed and direction.
After three months of testing, OSU researchers found that the areas shaded by solar panels grew double the amount of plant life compared to their uncovered counterparts. The nutritional value of the plant life also increased due to the optimal conditions of airflow, temperature, and overall climate.
Higgins and his team theorize that certain plants thrive under the shady conditions provided by the solar panels because the plants are, in essence, less stressed. When plants are subjected to constant sun rays, their water intake will greatly increase. This can cause the plants to grow substantially until they die out. On the other hand, when certain plants are able to take advantage of the shade cover provided by the solar panels, they flourish. According to Higgins, the shaded plants need only sip water sparingly, rather than consume large amounts in desperation.
Solar Power and Agriculture Working Together
Researchers at OSU are now honing in on which plants will function best in an agrivoltaic set-up. So far, aloe vera, lettuce, tomatoes, biogas maize, and pasture grass have shown the most promise. Certain lettuce varieties, in particular, have been shown to produce greater yields in shade than in sunlight.
With how promising these particular studies have been, we can hope to see more advocacy for agrivoltaics in the near future. Combining solar with agricultural production is the kind of forward-thinking focus our society needs to continue to create sustainable ways of living. Now that a mutual, symbiotic relationship between agricultural lands and solar panel placement has been established, we can expect to find solar panels popping up on farmlands soon.
Read the original OSU study here: https://www.nature.com/articles/s41598-019-47803-3