Perpsectives of developing agrovoltaic systems and analysis of their interplays with the water-energy-food nexus

Over the past decade, for environmental and economic reasons, Europe has intensified the transition to “green” energy. Renewable energy is the least land-efficient energy source, whilst the agricultural lands are being reduced year by year. Therefore, while planning renewable energy development, it should be taken under consideration the maintenance of the arable lands. Agrivoltaics, by combining food and energy production at the same land, can offer a progressive photovoltaic energy development. In agrivoltaic systems, photovoltaics are mounted on 4-5m stilts, aiming to utilize the area below for growing crops. The sun radiation that is available for plants is getting reduced, because part of it is being used by solar panels. The acceptable reduction rate is depending on each crop‟s needs. An adapting technique that plants have to shading caused by photovoltaics, is to increase the surface area of their leaves, i.e. to increase the area that absorbs solar radiation. Moreover, agrivoltaics create new microclimate conditions that reduce the evapotranspiration. In this work, the reduction of solar radiation reaching the ground was calculated depending on the configuration of the agrovoltaic system. For constant tilt angle solar panels, a decisive factor in radiation reduction is their placement density. Therefore, the effect of the photovoltaic shadow on crops was estimated for winter wheat, maize and alfalfa. For a dense photovoltaic placement, that is optimizing the energy production, the least affected crop was winter wheat while for reducing the density it was maize. Furthermore, the reduction in water needs due to the limited radiation reaching the crops was calculated.