Kolkata Metro to upgrade systems as Blue Line eyes 90-second frequency mirroring London, Moscow Metro services

Once completed, the passengers will have a more comfortable riding experience in Kolkata Metro, Asia’s fifth Metro network, said the officer. This upgrade with state-of-the-art technology will also ensure improved fire safety and save Rs 11 crore in annual electricity bill, as well as reduce carbon footprint by 12,300 Metric Tonnes annually, he added.

The Ministry of Railways has already sanctioned umbrella works to implement the ambitious projects.

Seven additional sub-stations — at Kalighat, Netaji Bhawan, Maidan, Esplanade, M.G. Road, Sovabazar-Sutanuti, and in between Belgachia and Shyambazar — will be constructed along its stretch to improve train operations in the Blue Line, Metro said in the statement.

With this, Blue Line shall have traction substations at each station, like the Purple Line and Orange Line.

“Orders for two Traction Sub Stations (TSS) at Chandni Chowk and Geetanjali have already been placed to meet the demand for additional traction power with fire safety. The TSS coming up at Chandni Chowk will help avoid congestion of rakes between Esplanade and Central stations, where there are two TSS for four stations,” said the officer.

Shifting to state-of-the-art Tunnel Ventilation System

In addition, the ventilation and cooling systems of the stations and tunnels are being upgraded. As the Kolkata Metro is now armed with a fully air-conditioned rake fleet, it provides the opportunity to shift to a state-of-the-art tunnel Ventilation System (TVS) and smoke extraction system.

“The existing system makes use of forced ventilation with centrifugal fans of 110 kW at 14 midpoints. These fans rotate 24X7 hrs and consume 3 crores units of energy annually for Rs 21 crore. By installing a variable frequency drive at the midpoint in 2021-2022, this consumption was reduced to half. These fans can rotate in one direction to work as exhaust fans. All these fans shall now be replaced by axial fans, which are suitable for two-hour operation even if the air temperature they handle reaches 250°C,” Kolkata Metro said in the statement.

These fans will rotate automatically in case of fire or smoke in the tunnel, or when the ambient temperature crosses the set limit, or when the concentration of carbon dioxide or sub-soil temperature inside the tunnels crosses the limit.

An Indian subsidiary of a Japanese company has taken up the work order to upgrade the Blue Line’s stations’ Environmental Control Systems (ECS) and the Tunnel Ventilation System (TVS). This holding company has already commissioned ECS and TVS systems in more than 100 underground Metro stations in the Singapore Metro.

A team of Japanese engineers has recently visited Jatin Das Park station’s air-conditioning plant and other areas.