The Blue Line, which stretches 32 km from Dakshineshwar to New Garia, now features the advanced aluminium third rail as part of a green energy initiative aimed at modernizing the metro system. This move is expected to enhance efficiency, reduce operational costs, and improve energy efficiency, contributing to the country’s green energy goals.
The third phase of the project began on November 30, 2024, covering the stretch from Girish Park to Central Station, including the intermediate Mahatma Gandhi Road station. A dedicated team led by Shri Sumit Kayal and Senior Section Engineer Abhishek Sinha replaced approximately 700 meters of steel third rail during a tight 5-hour window overnight to ensure no disruption to metro services during peak hours. The new system was installed with enhanced alignment precision, ensuring better safety for passengers.
Once completed, Kolkata Metro will join the ranks of other global cities, such as Singapore, London, Moscow, Berlin, Munich, and Istanbul, where aluminium third rails have already been implemented.
Kausik Mitra, Chief Public Relations Officer of Kolkata Metro, previously commented, “As Kolkata Metro celebrates its 40th anniversary, it joins the high-tech league by replacing outdated steel third rails with aluminium. This transformation will have a profound impact on metro operations.”
Compared to steel, aluminium third rails offer several advantages, particularly in electrical conductivity. Aluminium has a conductivity of 38 million siemens per meter, significantly reducing energy loss compared to steel's 6 million siemens per meter. This upgrade will improve operational efficiency, speed up train acceleration, and ultimately lead to cost savings over the next five years. Furthermore, the switch to aluminium is expected to reduce carbon emissions by 50,000 tons over the lifespan of the rail.
The project has been carefully planned with safety in mind. The new aluminium third rail requires less maintenance and has a longer lifespan. Unlike steel, which requires welding, the aluminium rails are connected using splice joints, a method that reduces the risk of cable fires and enhances air quality inside the tunnels. This focus on safety and reliability is expected to reassure passengers and stakeholders about the durability of the new system.
Kolkata Metro has awarded the contract to a German company with extensive experience in manufacturing and replacing third rails for more than 20 world-class metro systems. The replacement project is expected to be completed within two years. Aluminium third rails have already been successfully installed on the East-West Metro (Green Line) and the Joka-Taratala section of the Purple Line. This technology will also be rolled out across all future corridors of Kolkata Metro.
