Agrivoltaics Breakthrough: Solar Panels Boost Plant Remediation on Brownfields While Enhancing PV Performance
Key Insights
Researchers from Université de Lorraine have demonstrated that integrating solar PV systems with agromining on contaminated land offers dual benefits for environmental remediation and energy generation.
Solar panels provide protective shade for hyperaccumulating plants, leading to up to three times more biomass growth and an 18-fold increase in their solar energy conversion efficiency.
The evapotranspiration from plants under the PV modules creates a cooling effect, which can improve the solar panel's performance by approximately 18%, especially in sunny conditions.
This innovative approach presents a sustainable method for decontaminating brownfield sites while simultaneously enhancing renewable energy output, offering a novel solution for land use and resource recovery.
Researchers from France's Université de Lorraine have unveiled a groundbreaking approach that combines ground-mounted photovoltaic (PV) systems with agromining, demonstrating mutual benefits for both clean energy generation and environmental remediation on contaminated brownfield land. Their study, conducted in Bourget-du-Lac, France, revealed that solar panels not only protect hyperaccumulating plants, significantly boosting their growth and efficiency in extracting metallic trace elements (MTEs), but also benefit from the plants' cooling effect, enhancing PV module performance.
Agromining, a specialized branch of phytoremediation, utilizes hyperaccumulating plants to absorb MTEs from contaminated soils and store them in their aerial parts, which can then be harvested for industrial raw material recovery. This low-cost, plant-based method offers a sustainable alternative to conventional soil decontamination. The Université de Lorraine team specifically focused on Noccaea caerulescens, a plant known for its cadmium accumulation capabilities, in their experimental setup.
Their system comprised ground-mounted opaque and semi-transparent PV modules from Solarworld, Panasonic, and Jolywood, tilted at 30 degrees and elevated 0.8 meters, spaced 11 meters apart to minimize shading. Tests were conducted over fourteen weeks from July to November 2023. Comprehensive measurements, including PV module temperature, photosynthetic photon flux, wind speed, and global radiation, were meticulously collected to assess the interactions between the solar infrastructure and plant growth.
The findings, recently published in Applied Energy, showed a remarkable impact: plant biomass grew up to three times more under the PV panels compared to unshaded reference areas. Furthermore, plants cultivated beneath the modules exhibited an 18-fold higher capacity to efficiently convert solar energy. The scientists concluded that the shade provided by the PV modules offered optimal protection against intense solar radiation, promoting robust plant development.
Conversely, the research also highlighted a significant benefit for the PV systems. Plant evapotranspiration, through its natural cooling effect, was found to improve PV module performance by approximately 18%, particularly under pronounced sunny conditions. This suggests that integrating evapotranspiration into thermal modeling for PV modules could lead to more accurate energy production forecasts and potentially inform future module design for enhanced efficiency. This dual-purpose land utilization strategy presents a compelling model for revitalizing industrial wastelands while simultaneously advancing renewable energy objectives.