High-speed international trains linking Paris and Amsterdam as of Monday became the first in Europe to use electricity generated by solar panels installed in a tunnel on the line.
At a cost of 15.6 million euros, project managers say the 3.6-kilometre tunnel crossing Antwerp, in northern Belgium, is fitted with 16,000 solar panels covering 50,000 square metres, roughly eight football pitches.
The panels produce 3,300 megawatts per hour of electricity, or the average annual consumption of nearly 1,000 families.
The first "green train" left Antwerp on Monday for the Dutch border. While it was filled as usual with commuters and students, for a dozen or so kilometres, its engines plugged into the solar energy source fitted along the line.
The electricity produced feeds into the line's infrastructure, for lighting, signals and in-train power points, said Frederic Sacre, spokesman for Infrabel, which runs the rail network.
"By using electricity generated on-site, we eliminate energy losses and transport costs," said Steven De Tollenaere, head of project developers Enfinity, which leans on state subsidies backing energy use that meets clean climate goals.
The company hopes the project will allow it to develop new installations in the United States and other parts of the world, citing train hangars as ideal sites for such charging points in the future.
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