Switzerland Successfully Tests Solar Railways Feeding Local Power Grid

Solar panels installed between active railway tracks could become more common across Europe following positive results from a trial in Switzerland.

Swiss start-up Sun-Ways installed the world’s first removable solar power plant on an active railway line in Buttes, a village in Switzerland’s Val-de-Travers district, in April 2025. The installation covers 100 metres of track and includes 48 specially designed photovoltaic panels with a combined capacity of 18 kWp.

The project was initially approved as a three-year trial. However, Sun-Ways told Euronews Earth that its performance during the first year could lead to the installation of a permanent system along the railway.

Powering Railway Infrastructure

Electricity from the pilot installation currently goes directly into the local power grid.

Sun-Ways said it is also working on systems that could send electricity from future installations directly into railway substations or train traction lines.

The removable design allows railway operators to temporarily lift the panels when they need to inspect, repair, or maintain the tracks.

Nationwide Potential

Switzerland has approximately 5,317 kilometres of railway lines that could theoretically accommodate the technology.

Covering the entire network would use an area equivalent to around 760 football fields and more than 50,000 times the size of the current trial installation.

Sun-Ways estimates that panels installed across the network could generate around one terawatt-hour of electricity annually. This would equal approximately 2% of Switzerland’s total electricity consumption.

The company estimates that one kilometre of equipped railway could produce around 200 MWh each year, while its specialised installation train could place up to 1,000 square metres of panels per day.

Strong Energy Output

Solar panels usually perform best when installed at an angle that maximises their exposure to sunlight.

In Spain, for example, the most efficient angle is generally between 30 and 35 degrees. A 2022 study found that positioning panels at a 34-degree angle on the Iberian Peninsula resulted in annual production losses of less than 1%.

Railway panels cannot be tilted in the same way because they must remain flat between the tracks. Sun-Ways estimates that the flat position reduces production by only around 10%.

Despite this limitation, the Swiss installation produced approximately 16,000 kWh during its first year. This is roughly equal to the annual electricity use of an average fully electric home in the UK, including heating, hot water, lighting, and appliances.

Safety Concerns Addressed

Installing solar panels on active railway lines creates several safety and maintenance challenges.

The International Union of Railways previously raised concerns that the panels could develop microcracks, increase fire risks or distract train drivers by reflecting sunlight.

Sun-Ways responded by developing panels that are more resistant than standard rooftop models and adding anti-reflection filters. Built-in sensors monitor their operation, while brushes attached to trains can remove dirt from their surfaces.

The company said the installation operated without problems during its first year and required no special maintenance. More than 11,000 trains reportedly passed over the panels without affecting their stability or safety.

International Expansion

Following the Swiss trial, Sun-Ways signed a collaboration agreement with an Italian business partner that is in contact with Rete Ferroviaria Italiana, Italy’s national railway infrastructure operator.

The company expects to reveal plans for an Italian pilot project in the coming months. However, the agreement is with the local partner rather than directly with Rete Ferroviaria Italiana.

Sun-Ways has also received government approval for another solar railway installation in South Korea.

The company is holding discussions with businesses in the Netherlands, China, India, and Singapore as it seeks to expand the technology beyond Switzerland.