Kolkata Metro Railway is set to complete the replacement of the steel third rail with an aluminium third rail on the down line between Belgachia and Tollygunge (Mahanayak Uttam Kumar) on the Blue Line by August 2025, a spokesperson announced on Sunday (January 5).
The third rail, which supplies power to Metro trains, is being upgraded to an aluminium system to save significant energy and reduce operational costs. The replacement work has already been completed on the 4-km stretch between Shyambazar and Central stations on the down line.
In December 2024, approximately 3,500 meters of the third rail were replaced, and an additional 4,000 meters are now being replaced monthly to meet the August 2025 deadline for the entire underground section. Initially, the work was carried out during power blocks on Saturday nights, but it is now being conducted on weekdays as well, with strict safety measures in place.
The aluminium third rail offers better electrical conductivity, reducing system voltage drops and energy losses. This enhancement enables faster train acceleration, improving overall Metro efficiency. The operational cost savings from this upgrade are expected to recover the project’s expense within three years.
Furthermore, the aluminium third rail will significantly reduce carbon emissions, cutting 50,000 tons of emissions over its lifetime, contributing to a more sustainable Metro Railway system.