Container Plant Production under Photovoltaic-Panels and Within Screen Shade Structures

Plant producers have long used shading systems to protect plants from bright light and heat. The use of photovoltaic shade systems is a new approach to protected horticulture. By using photovoltaic panels, energy can be collected for the operation of the production facility. The growth response of plants shaded by solar panels is examined in this project. Three experiments were conducted. One experiment involves vinca (Catharanthus roseum) grown in an outdoor environment. The other experiment took place in a greenhouse. Genovese basil (Ocimum basilicum) and Black Seeded Simpson lettuce (Lactuca sativa) were used in the greenhouse experiment. The third experiment examines field crops in an outdoor environment.;Plants were grown from seed and/or cuttings and placed in various treatments ranging from full sun to high shade. The shade was provided by photovoltaic panels that allowed certain amounts of light through. Various canopy size measurements and above ground mass measurements were carried out as a way of comparing growth across treatments. Quality rating was also measured in the experiments involving vinca.;Trial 1 of the vinca experiments showed that bushier looking plants are produced in lower light environments. Higher light environments produce more dry mass, lighter leaves, and/or smaller appearance. In trial 2 however, some of these findings were not the same as trial 1. This indicates more trials are needed but general recommendations can be gleaned from similarities between the results in the two trials. In the greenhouse experiments, the basil and lettuce grew more without PV panels overhead compared to under the shade of PV panels. The refractive nature of photovoltaic panels in both sets of experiments did not appear to have an effect on plant growth, although further studies over multiple seasons are needed to confirm these findings. Lastly, the effect of photovoltaic shade on field crops seems to vary with each crop. Alfalfa seems to respond adversely to higher shade, while other crops produced fresh mass similarly between shaded and high light conditions. The results in general show that photovoltaic material can provide a shaded environment that produces high quality plants.