ITALY: Milano transport operator ATM has put into service a reversible substation at Rogoredo station on metro line M3.

Alstom has supplied a 1·5 kV 4 MW Hesop substation. This becomes the second Hesop substation in commercial operation on a metro line, following a 600 V 1 MW substation on the London Underground, which has been in operation since March 2015.

According to Alstom, the substation can return up to 15% of the traction energy generated when trains brake to the grid, with a further 84% able to be stored and reused to power accelerating trains. In addition to making M3 more energy efficient, the technology can help to control tunnel temperatures.

‘ATM has always paid great attention to the environment, so it is always interested in participating in innovative projects that allow greater energy efficiency and a lower environmental impact’, said ATM’s Energy Manager Miles Parisi. ‘This is another piece in the ATM policy towards a zero-emission company.’

Alstom’s sites in Rome, Charleroi, and Saint-Ouen were involved in the project, which was funded from the European Commission’s LIFE+ programme.