MUMBAI: Even as Mumbai braces for another season of record electricity consumption, one of the city’s biggest power security upgrades has quietly gone operational—one that experts say could fundamentally reduce the risk of transmission bottlenecks rather than simply add more electricity.While public attention has largely focused on increasing power generation, the bigger challenge for Mumbai is now moving electricity into the city. Industry executives say the Mumbai Urja Marg Ltd (MUML) transmission project has increased Mumbai’s ability to import over 2,000 MW of electricity—equivalent to nearly half of the city’s peak requirement—by creating a new high-capacity transmission corridor linking the metropolis to the national grid.The development assumes significance because Mumbai’s own power generation capacity has remained limited, making the city increasingly dependent on importing electricity from outside Maharashtra as demand rises due to rapid urbanisation, metro rail expansion, electric vehicles, airports and data centres.A less-reported angle is that the project does not merely add transmission lines but revives critical infrastructure that had remained underutilised for more than a decade. The project operationalised the 400/220-kV Navi Mumbai GIS substation, which had remained dormant since 2012, by integrating it with the Inter-State Transmission System (ISTS). This creates an additional entry point for electricity into Mumbai while easing pressure on heavily loaded substations such as Kalwa and Kharghar.Energy experts say this improves operational flexibility for grid managers during periods of exceptionally high demand or when maintenance shuts down parts of the network. The project also highlights how Mumbai’s electricity planning is shifting from creating generation assets to strengthening transmission infrastructure.“India’s urban power challenge is increasingly becoming one of transmission readiness rather than generation capacity. Cities need resilient transmission corridors capable of importing large volumes of electricity whenever required,” said Pratik Agarwal, Chairman of Resonia Ltd.The approximately 100-km corridor traverses some of the Mumbai Metropolitan Region’s most difficult terrain, including dense urban settlements, highways, railway lines, metro corridors, forests and rocky hills across Thane, Bhiwandi, Kalyan, Ambernath, Panvel and Navi Mumbai.Another relatively unexplored aspect of the project is the engineering approach adopted to minimise disruption in congested Mumbai neighbourhoods. Instead of conventional lattice towers requiring larger footprints, developers deployed ultra-narrow-base towers and monopoles that could be erected within narrow road margins. In forested stretches around Haji Malang and Raigad, helicopter-assisted stringing was used to transport equipment and lay conductors, reducing the need for heavy machinery and limiting ecological disturbance.Industry officials said the project also broke a nearly 12-year execution deadlock after overcoming complex right-of-way issues involving multiple government agencies and local stakeholders.Beyond improving reliability, the strengthened transmission network is expected to facilitate larger inflows of renewable energy generated in Gujarat, Rajasthan and other western states through the national transmission grid. That could gradually reduce dependence on local fossil-fuel-based generation while supporting Mumbai’s growing electricity demand.The project has been developed under the tariff-based competitive bidding framework on a Build-Own-Operate-Maintain model with an estimated investment of about USD 300-400 million.Power planners say such transmission investments are becoming increasingly important as Mumbai prepares for new electricity-intensive infrastructure, including the Navi Mumbai International Airport, expanding Metro corridors, high-speed rail connectivity and large data centres.
