size
capacity
Prof. Dr. Ulrich Kohnle
Forstliche Versuchs- und Forschungsanstalt Baden-Württemberg
agricultural research
Quarzsandwerk
Emil Steidle GmbH & Co. KG
Stromabnahme
Overhead system with fixed modules
coordinates: 47°57'22.5"N 9°10'20.5"E
The project
Overview
An innovative pilot project in Baden-Württemberg is demonstrating temporary combined use of land for reforestation and renewable energy. The project started in 2023 in a quartz sand quarry near Meßkirch-Rengetsweiler in the rural district of Sigmaringen. On 0.35 hectares, experts are studying the growth of young white and Nordmann fir trees under a PV system, and comparing the findings with an uncovered reference plot.
Forestry research questions
The Forest Research Institute Baden-Württemberg (FVA) is responsible for the accompanying scientific research. In order to assess the impacts of the PV plant on the growth of the young trees, two planting areas were set up: one area with 300 silver and Nordmann firs under the PV system and a comparison area with 300 young trees without any cover. FVA is focused on investigating the following key questions:
- How long can the PV plant be in operation? How long can the PV plant sensibly remain over the young trees before it needs to be removed because the growing trees are creating sufficient shade themselves?
- What influence does the PV plant have on tree growth? The focus here is on two hypotheses:
- Positive influence: The PV plant acts as a protective shield, reducing excessive sunlight exposure and creating a favourable microclimate for the growth of the shade-loving fir trees.
- Negative influence: The PV plant acts as a disruptive factor, restricting natural light conditions and leading to a worse development of the young trees compared with the uncovered area.
Technical features
The PV modules were installed on a demountable steel structure on removable, concrete-free, ground screw foundations. This was a key aspect when developing the plant, since the land is only intended to be used as a photovoltaic site on a temporary basis, during the early phase of a reforestation project. The PV plant will have to be removed again before the trees reach the PV modules, probably after around 10 years, depending on how fast the fir trees grow. Once the plant is dismantled, the idea is that it can be installed and operated on a different reforestation site.
for the location
