1. Traction current requirements can easily be covered

According to Fraunhofer ISE, photovoltaic systems with an output of up to 37.6 gigawatts could be installed within a two-kilometer radius of traction power substations alone. These could generate around 32,900 gigawatt hours of electricity annually – more than four times as much as the current annual electricity consumption of German rail transport. In 2023 this was around 7,500 gigawatt hours.

This shows that even with partial use of the existing areas, a large part of the traction power could come from direct solar energy.

2. Technology for rail: challenges and solutions

The traction power network uses a special frequency of 16.7 Hz – different from the usual power network with 50 Hz. Conventional inverters are not suitable for this. As part of PV4Rail, a special central inverter was developed that overcomes this hurdle.

The prototype produces 2 megawatts and achieves an efficiency of 96.6 percent. This means that different feed options can be used depending on the system concept – from direct feed into the overhead line to feed via substations or your own transformer stations.

Andreas Hensel from Fraunhofer ISE says: “However, a relevant part of the energy requirement in the traction power network could be covered by photovoltaics, because the photovoltaic area potential along the railway lines is many times higher than the amount of energy needed in the traction power network.”

3. Look at Austria: Practical examples available

In Austria, PV electricity is already fed directly into the traction power network – with systems that produce more than 10 megawatts. However, transferability to Germany is limited because the technical regulations and network conditions differ.

For Germany, this means: It needs its own pilot projects, adapted standards and clear processes for approval and grid connection so that nationwide expansion is possible here too.

4. Double effect: energy transition meets transport transition

Direct PV feed-in into the railway network could become a key project for two major challenges: a sustainable energy supply and a climate-friendly transport sector. The use of renewable energy in the rail network not only reduces emissions, but also costs in the long term.

The technologies are there – now it’s about reducing regulatory hurdles, securing investments and developing the necessary infrastructure with foresight.

Another advantage: the spatial proximity of electricity generation and consumption minimizes transmission losses and relieves pressure on the public power grid. This not only makes the energy supply more efficient, but also strengthens network stability – a central aspect in times of growing electromobility.

5. Conclusion – Photovoltaics as a future building block for the railway

PV4Rail shows: The integration of solar power into the traction power network is not only technically feasible, but also offers enormous economic and ecological opportunities. Through targeted use of the areas along the rail, large amounts of climate-neutral electricity could be fed in directly where it is needed.

For this to become reality, decisive action is needed from politicians, railway companies and industry. If planning security, technical standards and funding work together, PV4Rail can pave the way to a new, sustainable era of rail transport.

At the same time, PV4Rail opens up new perspectives for areas that have previously hardly been used economically. Railway lines, verges and technical zones become active energy sources – without additional competition for land from agriculture or housing construction. This makes the concept particularly sustainable and socially compatible.