Scientists discover efficient method of growing crops under solar panels
Scientists from the University of California, Davis, have come up with a method that can make agrivoltaic systems, the process of growing crops under solar panels, more efficient. In their study, they discovered that red wavelengths of the light spectrum are more efficient for growing plants, while the blue part of the spectrum is better for producing solar energy.
Why does this story matter?
- The world population just clocked a whopping eight billion which also places a massive burden on food security.
- At a time when there is a fast depletion of arable land, understanding how plants respond to different light spectra is an important step toward designing systems that balance sustainable land management with water use and food production, notes the study published in Earth's Future journal.
Researchers first developed a photosynthesis and transpiration model
The researchers developed a photosynthesis and transpiration model to account for different light spectra. This model reproduced the response of various plants, including lettuce, basil, and strawberry, to different light spectra under controlled lab conditions. Upon analysis, it was revealed that the blue part of the spectrum was best suited for solar energy production while the red spectrum could be optimized to grow food.
"We need something transformative"
"We cannot feed two billion more people in 30 years by being just a little more water-efficient and continuing as we do," said Abou Najm, corresponding author of the study. "We need something transformative, not incremental. If we treat the sun as a resource, we can work with shade and generate electricity while producing crops underneath. Kilowatt-hours become a secondary crop you can harvest."
The filters helped reduce heat stress and food wastage
This idea was further tested on tomatoes. Some plants were grown under blue and red filters, and a control crop was grown without any covering. It was discovered that the yield for covered plots was about a third less than the control, and the filters helped to reduce heat stress and crop wastage. The control, however, had about twice the number of rotten tomatoes.
The study could help identify applications for agrivoltaic systems
There are some issues, though. The study concludes that "plant response to different light treatments is most likely species-specific," which means that wavelength-selective agrivoltaic systems may need to account for different types of crops, and harvesting these crops requires some thought as well. On the positive side, the study's results could help guide global interest in agrivoltaics and identify potential applications for those systems.