Switzerland’s Removable Solar Railway: A First Working Test Between the Rails
A Swiss start-up has placed photovoltaic modules directly between the rails of an operating railway line. The installation, developed by Sun-Ways, is located near Buttes in the canton of Neuchâtel. It is designed to generate electricity without occupying additional land and to be removed when railway maintenance requires access to the track.
The project is important because it tests a difficult combination of requirements in a real railway environment. The panels must remain stable while trains pass over them. They must not obstruct inspections, track work, or emergency procedures. They must also avoid creating unacceptable glare for drivers and must deliver electricity through an electrical system compatible with railway operations.
Sun-Ways installed the pilot on 24 April 2025. The test section is 100 metres long and contains 48 photovoltaic panels rated at 380 watts each. The total installed capacity is approximately 18 kilowatt-peak (kWp), according to SNCF Group, which is studying the technology with the Swiss company. The pilot is scheduled to run until April 2028.1
How the removable system works
The panels are installed on the sleepers, the structural elements that support and maintain the position of the rails. Their position keeps the solar surface inside the track gauge while allowing train wheels to run on the steel rails. The system is modular rather than permanently built into the railway bed.
Sun-Ways says its design can be installed and removed in sections. A three-panel module measuring about six metres can reportedly be disconnected from the power system and detached from the track in roughly ten minutes with dedicated tools. This matters because railways periodically replace sleepers, weld rails, inspect geometry, clear debris, and carry out other work that cannot be performed around a fixed solar structure.2
The company also presents a specialised railway machine developed with Scheuchzer to lay and remove panels. A mechanised installation method could reduce the time that maintenance crews spend working on an active line. It could also make phased deployment possible, with solar sections taken out only where work is needed.
The prototype is marketed as suitable for train speeds up to 150 kilometres per hour. The trains on the Buttes section reach a maximum of about 90 kilometres per hour, so the pilot does not yet represent every possible operating condition. The distinction is important: a claimed design capability is not the same as a completed approval for every railway type.2
Early operating results
The first operating data are encouraging, although the installation remains a test rather than a commercial national rollout. Swissinfo reported in June 2026 that more than 11,000 trains had passed over the panels. Sun-Ways founder Joseph Scuderi said the modules had remained stable and safe during those passages.2
The plant generated more than 16,000 kilowatt-hours (kWh) from 20 May 2025 onward, despite a shutdown of approximately one month caused by snow and planned work to integrate a technical component. That output is comparable to the average annual electricity consumption of three to four households. The electricity is fed into the local grid rather than directly powering the trains on the pilot section.2
The passing trains have also provided an unexpected operational benefit. Sun-Ways initially considered using a cylindrical brush mounted on a train to remove dust from the panel surfaces. The company later concluded that the airflow generated by passing trains helps sweep away dust. This observation still needs to be assessed over longer periods, through different weather conditions, and on lines with different speeds and traffic patterns.
Pilot facts at a glance
Item | Reported specification or result |
Location | Buttes, canton of Neuchâtel, western Switzerland |
Commissioning | 24 April 2025 |
Test length | 100 metres |
Panels | 48 photovoltaic modules |
Panel rating | 380 W each |
Installed capacity | About 18 kWp |
Pilot duration | Planned through April 2028 |
Reported train passages | More than 11,000 by June 2026 |
Reported generation | More than 16,000 kWh after 20 May 2025, with a roughly one-month interruption |
Local train speed | Up to about 90 km/h |
Removal example | Three-panel, six-metre module in about ten minutes |
Safety, glare, and maintenance remain central tests
Railway solar power must meet a higher operational threshold than a conventional rooftop installation. A panel failure, loose component, obstructed inspection, or reflective surface could affect railway safety. For this reason, the pilot evaluates installation procedures, glare, track inspection, maintenance impacts, output, and dirt accumulation.1
TransN, the public transport operator responsible for the Buttes section, told Swissinfo that the system had not conflicted with infrastructure, maintenance, or train traffic. The operator had also received no reports of glare from its staff at the time of the report.2 These are positive observations, but they are site-specific. Other routes may have different curves, gradients, signalling equipment, speeds, sun angles, and maintenance practices.
Swiss Federal Railways, which manages most of Switzerland’s railway network, is monitoring the project but is not a project partner. The company has indicated that its own photovoltaic plans focus on buildings, stations, noise barriers, and maintenance centres rather than panels between rails. That position shows that track-mounted solar is being treated as one option among several, not as a replacement for every other form of railway solar generation.2
The electricity challenge: generation is only half the system
A long line of photovoltaic modules produces electricity across a narrow corridor. Moving that electricity efficiently to a useful connection point can be harder than installing the panels. Julien Pouget, an associate professor at the University of Applied Sciences of Valais, has warned that a dedicated electrical architecture is needed for stretches longer than about 500 metres with current technology. Voltage must be raised when electricity is transported over longer distances, and the design must account for railway traction systems and grid rules.2
Sun-Ways estimates that suitable sections of Switzerland’s railway network could eventually produce up to one billion kWh of solar electricity per year. The company compares that figure with the consumption of about 300,000 households and roughly 2% of Swiss electricity use. This is a company estimate, not a demonstrated result from the Buttes pilot. It excludes tunnels and sections with poor solar exposure, and it would depend on approvals, electrical connections, maintenance access, weather, and the economics of large-scale deployment.2
The pilot therefore has two outputs. The first is electricity. The second is evidence about whether solar equipment can coexist with railway engineering rules over time.
Why other European railways are watching
France has shown the clearest European interest so far. In February 2026, SNCF Group announced a technical cooperation agreement with Sun-Ways. SNCF and SNCF Réseau teams are studying how the equipment affects maintenance operations and are using the Swiss pilot to collect technical feedback. The cooperation is planned around the current test period, which runs to April 2028.1
France has a large rail network and significant electricity demand. SNCF says it manages about 28,000 kilometres of railway lines and intends to cover 20% of its energy consumption with photovoltaics by 2030. Panels positioned within existing rail corridors could avoid some of the land acquisition and expropriation issues associated with building solar plants next to tracks. That advantage would have to be balanced against safety approvals, electrical integration, cleaning, replacement cycles, and the cost of specialised installation equipment.2
Italy is also a potential next market. Sun-Ways has reported discussions with Rete Ferroviaria Italiana, the company responsible for Italy’s railway infrastructure. Italy’s interest is linked to plans to feed more solar power into railway traction systems. A pilot would be needed to determine whether the Swiss design can operate under Italian track standards and local climate conditions.2
Outside Europe, partnerships and exploratory projects have been reported in South Korea and Indonesia. South Korea approved a two-year pilot near Osong station in Chungcheongbuk-do province in September 2025. These developments suggest that the concept is attracting international attention, while also showing that each country will need its own testing and approval process.2
A carefully reversible model for railway decarbonisation
The Buttes installation offers a practical answer to a specific question: can a railway operator use the unused strip between rails for solar generation without permanently changing the track? Early results suggest that the answer may be yes under the tested conditions. More than 11,000 train passages, positive comments from the local operator, and more than 16,000 kWh of reported generation provide a useful operational base.2
The next phase must establish performance over a longer period and across more demanding routes. It must confirm how the modules behave during snow, heat, vibration, maintenance work, emergency access, and changes in track geometry. It must also clarify the cost of installation, removal, electrical connection, inspection, replacement, and end-of-life recycling.
If those questions are answered positively, removable photovoltaic systems could give railways another source of renewable electricity without requiring a new land corridor. Switzerland has supplied the first live demonstration. France, Italy, and other interested countries will determine whether the method can move from one carefully monitored section to a repeatable railway standard.
References
Comments