A team of scientists from Swansea University, UK, developed a tool to identify the optimal photovoltaic materials to both maximise crop growth and generate solar power, according to a study published in Solar RRL.
The researchers have been working on the effect of semi-transparent photovoltaic (PV) materials placed over crops. This is an example of agrivoltaics, where solar panels are combined with agricultural settings. As part of this work, the team created a tool to predict the light transmission, absorption, and power generation of PV materials in different locations around the world using geographical, physical, and electrical measurements.
“This technology, which allows us to compare many types of PV material, could help us determine how we balance food production and renewable energy generation,” said Austin Kay, lead author of the study and a PhD candidate at Swansea University.
A critical factor in optimising agrivoltaics is selecting the best materials. This decision needs an understanding of how materials absorb different wavelengths, as well as their bandgap. A wide bandgap means the material can absorb high energy and short wavelength light (blue), while a narrow bandgap absorbs low energy long wavelength light (red).
By carefully selecting photovoltaic materials with specific bandgaps and absorption properties, researchers can fine-tune the colour of light that goes through semi-transparent photovoltaics to hit the crops, which absorb red and blue light to photosynthesise (reflecting green light).
“By optimising the combination of solar panels and agriculture, agrivoltaics has the potential to significantly contribute to the decarbonisation of the agricultural sector. This approach not only generates clean energy but also enhances food security,” said project lead Associate Professor Ardalan Armin.
The authors suggest that farms can use solar panels to provide locally generated power with minimal impact on the crop’s yield. They can be placed on the roofs of greenhouses or polytunnels and can also be used to provide shelter for livestock. In return, the livestock can reduce maintenance costs by eating vegetation around the panels.
Kay A, Riley D, Sandberg O, Burwell G, Meredith P, Armin A (2024) On the Performance Limits of Agrivoltaics—From Thermodynamic to Geo-Meteorological Considerations. Solar RRL, https://doi.org/10.1002/solr.202400456