The project investigated the integration of photovoltaic (PV) systems into railway infrastructure with a focus on direct injection into the 15‑kV overhead line. It was carried out in three work packages that were presented to a research‑supporting working group of specialists. The first work package performed a systematic market survey of PV systems that are either already installed or under development for railway use worldwide. The survey covered all necessary components for direct injection, including inverters, protection devices, and cabling, and identified suitable manufacturers and developers. The study also examined the mechanical loads that PV modules would experience on track beds, noise‑barrier walls, and other structural elements, as well as the effects of dust, corrosion, and maintenance requirements. Safety aspects such as protection against electric shock and electromagnetic compatibility were evaluated in detail. The results were documented in a series of chapters that correspond to the nine sub‑topics of the first work package, ranging from structural prerequisites to cost estimates for baseline systems.
The second work package quantified the technical PV potential of the German railway network. Using data from Deutsche Bahn databases and detailed cartographies of noise‑barrier walls and other railway structures, the team calculated the available surface area for PV installation, the maximum feasible power injection, and the expected annual energy yield. The analysis also considered the connection of generation‑proximate internal consumers to the railway grid. Although specific numerical values are not provided in the excerpt, the methodology included a rigorous assessment of the energy demand of individual trains and the overall traction energy consumption, allowing a comparison between the available PV potential and the required traction power.
The third work package focused on the regulatory framework. It reviewed technical regulations, PV grid‑connection rules, environmental protection directives, building codes, and other relevant authorities’ requirements. The study identified potential constraints, synergies, and barriers to implementation, and proposed solutions to align PV projects with existing railway standards.
Collaboration was central to the project. TÜV Rheinland led the effort, coordinating the work packages and integrating the findings into a comprehensive report. Deutsche Bahn supplied critical data sets and operational insights, while manufacturers and developers provided detailed product specifications and performance data. Academic partners from universities and research institutes contributed expertise in PV technology, structural analysis, and environmental impact assessment. The working group of experts facilitated peer review and ensured that the results reflected current industry practice. The project was funded by a German federal transport agency, with a planned duration of three years, during which the three work packages were completed sequentially.
In summary, the project delivered a detailed technical assessment of PV integration into railway infrastructure, covering system design, mechanical and safety considerations, regulatory compliance, and the quantification of available PV potential. It also established a collaborative framework that combined industry, academia, and infrastructure operators, providing a solid basis for future deployment of PV systems on the German railway network.