02 August 2023: So far there has been a discussion in Germany that PV solar fields are blocking valuable agricultural farmland, because they are usually mounted very low. However in Au in the Hallertau in Bavaria a high-mounted PV system was inaugurated: Tall growing hop plants there will be grown on an area of 1.3 hectares and at the same time solar energy will be produced for around 200 households. (Weekly magazine “Landwirtschaftliches Wochenblatt, 21 July 2023, p. 45): There were invested around 1.5 million euros in the scientifically supported project. The PV modules are mounted on 6 metres high stable steel masts, on which the hop plants can grow at the same time. However, only 80 percent of the usual electricity yield is expected because fewer PV modules are installed so that the plants do not get too much shade.
The potential in the Bavarian Hallertau region for these high-mounted PV modules is huge, because hops are grown on 17,200 hectares. Farmers can use this large area twice: for hop cultivation and for solar energy. At the same time, the solar modules can be very useful from an agricultural point of view. Because the plants benefit from protection from too much sun or hail and less evaporation. The German state of Bavaria holds amidst all German estates the top position in the field of solar energy by a wide margin: 750,000 solar systems currently produce more than 20 GW of electricity. https://www.br.de/nachrichten/bayern/agri-pv-photovoltaik-landwirtschaft-soeder-aiwanger-kaniber-fraunhofer-energiewende,TiffokW. According to Trommsdorff, from German Fraunhofer Institute around 30 systems are currently installed in Germany. How powerful a system is per hectare depends on how close together the solar panels can be built. The question is: How much shade can a plant tolerate? Or: how big does the distance between the module rows have to be in so-called ground-level systems?
https://www.br.de/nachrichten/bayern/dank-solarenergie-auch-in-zukunft-noch-hopfen-in-bayern,TifuTid
“With agri-photovoltaics (agri-PV) or agrophotovoltaics, agricultural land can be used for plant production and solar power generation at the same time. Photovoltaic modules are mounted on high frames so that the area below can be used for agricultural purposes. Agri-PV is not only used in fields with low-growing crops such as potatoes, but also for higher-growing special crops such as hops or fruit. Depending on the system design, the complex, stable constructions are sometimes more than four meters high, so that tractors and combine harvesters can drive underneath.
Advantages: Due to the dual use of agricultural land, the competition between energy and food production is defused - in Germany, energy crops are grown on a good 14 percent of agricultural land instead of food. In addition to more efficient soil use, Agri-PV can increase harvest yields: the solar modules sometimes support plant production through shading effects at high temperatures and, depending on the design, offer protection against heavy rain, hail and frost.
Disadvantages: In contrast to photovoltaic ground-mounted systems, however, agri-PV systems are usually more expensive and tend to produce less electricity per area.”
Please see also Renewable Energies/Sun/Photo Voltaic (ohne Agriculture)
