Solar energy and groundwater protection combined
SENS revolutionises solar energy: 13.5 MWp solar park defies high groundwater level for sustainable power generation
In northern Germany, where water, wind and sun determine the weather, a fascinating spectacle unfolds. The maritime climate of the North Sea shapes the region; while the winds are stronger in winter, mild breezes blow in summer. But it is not only the climate that is a special feature for the construction of an open-space PV plant in Kropp, Schleswig-Holstein. The choice of location is also unusual in this case: in a former gravel extraction area with a high groundwater level, planning and implementation are required to ensure efficient solar energy generation as well as permanent groundwater protection. With the construction of a 13.5 MWp solar park in Kropp, the SENS team has implemented an important example of the energy turnaround.
Solar energy in northern Germany
With 24,500 solar modules and a total output of 13.5 MWp, the solar park in Kropp, near Kiel, represents a significant step forward in sustainable power generation. The plant will produce 13,500 MWh of renewable energy per year, saving about 6,000 tonnes of CO2 annually. Construction of the solar park began in January 2023 and could now be completed just five months later, after the plant was connected to the local power grid.
Location with challenges
When planning and constructing the solar park, the experts from SENS had to take into account several challenges that arose from the construction site. On the one hand, the location in northern Germany is exposed to strong winds due to the maritime climate, which meant that a special construction method for the modules was required. For this reason, two modules were installed vertically to optimally withstand the wind forces.
Two vertically installed modules on untreated substructure
On the other hand, the area was a former gravel extraction site that was filled with sand, which resulted above all in special features for the statics and load-bearing capacity of the substructure. This resulted in a small post spacing of only 1.30 meters. In addition, the area used has a high groundwater table, which is why correspondingly high requirements with regard to groundwater protection had to be taken into account in all project phases. The dangers of corrosion, the decay of materials due to a chemical reaction (e.g. the oxidation of metals), also had to be taken into account in the planning and design of the substructure. Therefore, the posts have a stronger cross-section in order to counteract the corrosion that occurs and to be able to have a permanently stable static.
In order to optimally solve these challenges, the substructure of the solar park was planned and implemented with twice the amount of untreated driven piles, as the embedment depth of the posts is only 1.1 meters due to the high groundwater level. In this way, both the stability under the given wind load and the protection of the groundwater can be guaranteed.
The construction of ground-mounted PV systems in water protection areas or areas with a high water table, such as in Kropp, has been made easier by the enormous interest in the expansion of solar energy. Nevertheless, it must be ensured that the ecological functions of this sensitive area are not impaired by only using certain materials and coatings. The SENS team has already found and implemented special solutions for projects with such requirements. In addition to this project in Kropp with a high groundwater table, a solar park was also built in a Zone II water protection area.
You can find out more about PV in water protection areas in general here.
Energy transition through innovation
"The conversion of the site in Kropp into a regenerative energy source is an impressive example of land revitalisation, despite the special climatic and site-related challenges. The project demonstrates once again that innovative approaches and solutions can drive the energy transition. I am proud that our team is taking on new challenges to shape a future with 100 % good energy," Fabian Herr, COO of SENS, summarises the project.
The project at a glance:
Electricity generation per year
CO2 savings per year