NalpSolar pioneer project: First 10% of alpine solar plant connected to the grid

21.10.2025 - Axpo and the municipality of Tujetsch (Grisons) have reached a key milestone at the NalpSolar alpine solar plant: in line with Switzerland’s “Solar Express” framework, the first 10% of the planned capacity has been successfully connected to the grid on schedule. Located at approximately 2,000 metres above sea level near the Lai da Nalps reservoir, the project is creating a new source of climate-friendly electricity to support the Swiss Federal Railways’ (SBB) sustainable traction power supply.  

In the high-alpine terrain above Tujetsch, the partial grid connection marks further progress towards the plant’s total installed capacity of around eight megawatts. Over recent months, more than 150 solar tables have been installed, each equipped with ten photovoltaic modules. CKW, an Axpo subsidiary, carried out the electrical connection of the modules. A technical building housing the required components was commissioned on time. Depending on weather conditions, construction will continue this year. NalpSolar will deliver renewable electricity with a high share of winter energy and is being implemented under the Solar Express programme.

Alpine solar installations face specific challenges – including demanding logistics and construction in high mountain terrain, short weather windows, snow and ice loads, and heightened requirements for corrosion and wind resistance – which are being systematically addressed in the NalpSolar project through robust components, carefully planned construction processes, and close collaboration with local partners.

Tujetsch: a local energy pioneer

Thanks to the pioneering spirit of the municipality of Tujetsch, Axpo is gaining valuable experience to advance solar energy in alpine environments.

Oliver Hugi, Head of Solar Switzerland at Axpo, said: “With NalpSolar, we are strengthening renewable electricity production in the Surselva and making a direct contribution to the SBB’s sustainable traction power supply. Our collaboration with Tujetsch shows how, together, we can tangibly move the energy future forward.”

Contribution to SBB traction power

With an expected installed capacity of around eight megawatts, NalpSolar will produce approximately eleven gigawatt-hours of renewable electricity per year. The solar power will be purchased by SBB over a 20-year period, supporting a reliable, climate-friendly supply to Switzerland’s railway power network.

Next construction phases

Work is progressing according to plan. The next construction stages will be completed step by step over the coming summer months, enabling the plant to reach full production capacity by 2028. With NalpSolar, Axpo reaffirms its commitment to expanding renewable energy and continues its long-standing partnership in the Surselva, now complementing hydropower with an increased focus on solar. The expansion of renewables remains a strategic priority for Axpo.