Ensuring the efficiency of technological systems is a key requirement of any transport system in order to guarantee its safety and sustainability

Colas Rail Italia has been awarded the contract for the technological upgrade and enhancement of part of the power supply and electric traction systems of the Line 2 (M2) of the Milan Metro, also known as the Green Line.

Works include the replacement of all the electromechanical equipment of the Electrical Conversion Substations which present a high degree of obsolescence as well as the renewal and replacement of the overhead contact line system.

The activities include the following:

  • Refurbishment of the Cologno Nord and Gessate  substations
  • New Cantalupa substation, in container
  • Replacement of n. 9 transformer station on the Cascina Gobba – Gessate and Cascina Gobba – Cologno Nord sections
  • Replacement of the contact line on the Cascina Gobba station – Cologno Nord station section
  • Works on the overhead contact line in the Assago / Abbiategrasso – Gobba – Gessate / Cologno sections



Milan, Italy


Azienda Trasporti Milanese




Technological and efficiency improvements of the designed solutions, including:

  • Installation of Tristor converters in substations in order to reduce the line voltage drop
  • Installation of high-performance transformers and converters
  • Provision of a mobile substation, mono-group
  • Various technological improvements related to the overhead contact line system aimed at increasing the performance and maintainability of the whole system

Discover our project