The Swiss start-up Sun-Ways wants to install solar modules on railroad tracks to generate green electricity. A special train will roll out the solar modules between the rails. More about the solar rail project here.
The Swiss start-up Sun-Ways wants to install solar modules on railroad tracks to generate green electricity. A special train will roll out the solar modules between the rails. More about the solar rail project here.
There are thousands and thousands of kilometers of railroad tracks in Europe. In Germany alone, the rail network measures around 40,000 kilometers. More and more efforts are being made to turn trains into a climate-friendly means of transportation, for example by running them on renewable electricity. The Swiss start-up Sun-Ways is now proposing that the tracks themselves could contribute to climate protection as solar rails.
Their idea of installing solar modules on railroad sleepers is not new. The modules do not take up any extra space, but cover the already sealed track area. And as the rails are standardized, solar panels are easy to plan and install. Railroad company employees regularly maintain the tracks anyway, and the existing overhead lines could easily feed the electricity generated into the local distribution network.
Sun-Ways has announced the launch of a pilot project for May 2023. A section of track in the Swiss canton of Neuchâtel is to be equipped with solar modules. The track is to measure ten kilometers by 2024. The results of the pilot project should show how great the potential of solar rails is for generating green electricity.
The idea of solar rails is not new, but Sun-Ways scores with a special installation method for the panels. These are pre-assembled in a factory and loaded onto a special train from the Swiss track construction company Scheuchzer. This train then travels along the track and rolls out the panels like a carpet between the rails. As soon as the solar cells are in place, the train triggers a mechanism to clamp the modules between the rails. In the next step, skilled workers manually connect the panels to the grid.
The 3D animation from Sun-Ways shows what the solar rails could look like in practice:
According to Sun-Ways, this approach has great potential. In Switzerland alone, an area of around seven square kilometers could be available for solar power in track beds. Sections of track in tunnels or with a lot of shade have to be excluded. In total, the electricity generated could supply around 350,000 households with electricity. Switzerland could generate around one terawatt hour of green electricity per year. That is two percent of the country’s current electricity consumption. Sun-Ways emphasizes that it does not offer a solution for the entire energy transition, but it does provide an important small building block.
And later use is also taken care of: according to Sun-Ways, it is possible to quickly collect the solar rails again and install them again later. This is particularly important when maintenance work is being carried out on the tracks, where the panels tend to get in the way. The start-up is therefore planning a flexible system.
There were similar hopes in the past for solar roads consisting of specially hardened solar modules. However, a pilot project in France failed due to the high costs, many damaged panels and the unexpectedly loud noise of car tires on the synthetic resin surface. As a result, there is now also skepticism about the proposed solar panels in the track bed. According to experts, the implementation of solar rails is challenging. Martin Heinrich from the Fraunhofer Institute for Solar Energy Systems, for example, told Der Standard that maintenance poses a major challenge. He is concerned that the solar modules could hinder or delay the maintenance of sections of track.
As with the solar road, the load on the panels is also a concern with solar rails. This is because trains travel over the solar cells at high speeds, causing stone chipping, among other things. The abrasion from the rails and train wheels could soil the panels and regular cleaning increases the maintenance effort immensely. If the solar modules come loose, this could even endanger train traffic. Although standard modules are already very robust, particularly high safety requirements are needed when using solar panels in the track bed. And feeding the electricity generated into the grid is also still a question mark. According to Sun-Ways, the electricity produced cannot yet be fed into the trains. However, it should be possible to pass the electricity on to nearby households. In future, it should be possible to connect the panels to the traction current grid.
Sun-Ways has many answers to the skeptical comments. Among other things, the start-up points out that the solar rails are easy to maintain. Cleaning is possible with cylindrical brushes on trains, and in winter a special system could melt snow and ice so that the solar cells continue to function. An anti-glare filter should also help prevent train drivers from being dazzled. Over the next few years, Sun-Ways would like to export to Germany, Italy, Austria, Asia and the USA.
Solar modules on railroad sleepers are also being tested elsewhere. The British company Bankset Energy, for example, is testing the idea on a Deutsche Bahn test field in the Ore Mountains. This involves the use of narrower solar modules that are placed individually on the sleepers. The results are not yet known.
However, it is questionable whether the technology is urgently needed. Deutsche Bahn, for example, already uses 65 percent renewable energy in its traction current, while in Austria a third of the traction current comes from ÖBB’s own hydroelectric power plants. According to Deutsche Bahn, the ICEs, ICs and ECs already run on 100 percent green electricity.
