The roof of a two mile stretch of tunnel over Belgium's high speed rail line has been fitted out with 16,000 solar panels to provide power for trains running through Antwerp Central Station and the surrounding railway infrastructure. Solar solution provider Enfinity says that about 4,000 trains per year - or the equivalent of a full day's worth of Belgian rail traffic - will be able to run entirely on solar power generated by the installation.

Engineers began covering the 50,000 square meter (164,000 sq ft) surface area of the roof of Belgium's HSL4 high-speed rail tunnel with monocrystalline solar panels (rated at 245 Wp per panel) in the summer of last year. The panels have been installed using a special ballast tile structure which negates the need for rooftop perforations. Enfinity says that the installation has just started generating the estimated 3.3 GWh* of electricity per year - equivalent to the average annual electricity consumption of nearly 1,000 homes.

The municipalities of Brasschaat and Schoten, intermunicipal financing companies FINEA and IKA, and solar construction company Solar Power Systems joined Enfinity and Belgian rail operator Infrabel for the Solar Tunnel project, which is said to be the first time railway infrastructure has been used to generate green energy. The cost of the project was around US$20 million.

The solar energy will be used in Antwerp's North-South junction to meet the electricity needs of the signaling, lighting, heating of railway stations, and also by the trains using the Belgian rail network.

In related news, the UK's Network Rail recently announced that the new Blackfriars Station, that is to span the River Thames, will have half of its electricity needs met by solar panels installed on the roof.

*Chloé Van Driessche from Enfinity's Belgian headquarters has confirmed that the amount generated annually is 3.3 GWh, not 3.3 MWh as previously stated by the company's U.S. office.