Agrivoltaic system impacts on microclimate and yield of different crops within an organic crop rotation in a temperate climate

Abstract

Agrivoltaic (AV) systems integrate the production of agricultural crops and electric power on the same land area through the installation of solar panels several meters above the soil surface. It has been demonstrated that AV can increase land productivity and contribute to the expansion of renewable energy production. Its utilization is expected to affect crop production by altering microclimatic conditions but has so far hardly been investigated. The present study aimed to determine for the first time how changes in microclimatic conditions through AV affect selected agricultural crops within an organic crop rotation. For this purpose, an AV research plant was installed near Lake Constance in south-west Germany in 2016. A field experiment was established with four crops (celeriac, winter wheat, potato and grass-clover) cultivated both underneath the AV system and on an adjacent reference site without solar panels. Microclimatic parameters, crop development and harvestable yields were monitored in 2017 and 2018. Overall, an alteration in microclimatic conditions and crop production under AV was confirmed. Photosynthetic active radiation was on average reduced by about 30% under AV. During summertime, soil temperature was decreased under AV in both years. Furthermore, reduced soil moisture and air temperatures as well as an altered rain distribution have been found under AV. In both years, plant height of all crops was increased under AV. In 2017 and 2018, yield ranges of the crops cultivated under AV compared to the reference site were −19 to +3% for winter wheat, −20 to +11% for potato and −8 to −5% for grass-clover. In the hot, dry summer 2018, crop yields of winter wheat and potato were increased by AV by 2.7% and 11%, respectively. These findings show that yield reductions under AV are likely, but under hot and dry weather conditions, growing conditions can become favorable.

Tomatoes from the desert: Environmental footprints and sustainability potential in a changing world

“…While in cool climates, it is less desirable to place a PV system on top of the growing structure, as too much light is blocked (Hollingsworth et al, 2020), it has many benefits in warm areas. As such, the additional shade increases yield reduces evaporation and pest development and improves the PV system performance due to the cooling effect of the underlying plants (e.g., Ezzaeri et al, 2018;Weselek et al, 2019Weselek et al, , 2021Barron-Gafford et al, 2019). Furthermore, this clean energy can enable installing a cooling system in the greenhouse to increase yields and extend the growing season without significantly impacting the environment (Waller et al, 2021).…”

Contrasting yield responses at varying levels of shade suggest different suitability of crops for dual land-use systems. A meta-analysis.

“…However, key figures of agricultural yields in these systems could not be standardized due to missing data of crop yield responses in AV and a lack of synthesized knowledge of crop yield responses in the shade in general. Although some crops can show yield reductions due to e.g., alteration of microclimatic conditions in shaded systems (Weselek et al 2021), some crops can even adapt their morphology or physiology, leading to low or no yield losses (Arenas-Corraliza et al 2019). Depending on the general climatic condition of the evaluated location, crops can benefit from shading in hot and dry areas (Barron-Gafford et al 2019), leading to synergies known in intercropping systems, but without competition for nutrients and water.…”

The 5 Cs of Agrivoltaic Success Factors in the United States: Lessons from the InSPIRE Research Study

“…It should be noted that agrivoltaic and ecovoltaic projects are not mutually exclusive. Crop production systems include the cultivation of annual and perennial food, fiber, or specialty crops underneath and around solar infrastructure (Mamun et al 2022;Trommsdorff et al 2021;Weselek et al 2021;Barron-Gafford et al 2019;Jo et al 2022;Valle et al 2017). Crop production systems are affected by the partial shade of solar infrastructure; crops can be grown directly underneath panels and in between rows of panels.…”