The city of Mumbai has now achieved National Grid connectivity at 400kV, thanks to a transmission system newly commissioned by Adani Energy Solutions Ltd (AESL), formerly known as Adani Transmission Ltd.
The new transmission system was commissioned by special purpose vehicle “Kharghar Vikhroli Transmission Ltd,” (KVTL) owned by Adani Energy Solutions Ltd – the power T&D arm of Adani Group.
The new system – comprising infrastructure at both 220kV and 400kV voltage levels – will enable additional power to be brought into Mumbai, helping the city meet its growing and electricity demand.
The project is critical for Mumbai as the existing capacity of the transmission corridor is not sufficient to carry further power into the city. It may be recalled that Mumbai witnessed major grid failure on two occasions in recent history – on February 27, 2022, and earlier on October 12, 2020.
Additional 1,000 mw power
The Kharghar-Vikhroli line will bring additional 1,000 mw of reliable power to Mumbai city as a solution to mitigate any such incidents in the future. With this project’s commissioning, Mumbai gets a 400KV grid within its municipal geography, bringing enhanced import capability within its electricity grid and improving reliability and stability, AESL said.
For consumers, it provides that much more sustainability to commuting through bullet trains, Metro Rail and city railways, as also for commercial and residential establishments.
System elements
KVTL comprises approximately 74 ckm of 400kV and 220kV transmission lines, along with a 1,500 MVA, 400kV GIS substation at Vikhroli. The KVTL project starts in the Kharghar area of Navi Mumbai, traverses through its urban locations and terminates at Vikhroli in Mumbai city. The project includes the following major elements:
- 400kV/220 kV GIS Vikhroli substation, having 1500 MVA transformation capacity
- Air insulated switchyard at Kharghar
- 400kV double/multi circuit Kharghar-Vikhroli line
- 400kV loop-in loop-out (LILO) on Talegaon-Kalwa line at Vikhroli
- 22 kV LILO on Trombay-Salsette line at Vikhroli
First 400kV GIS in Mumbai
Incidentally, the new Vikhroli substation is the first GIS substation in Mumbai at 400kV level. Having just 9,500 sqm of geographical footprint, it has the most compact design when it comes to 400 KV substations. Its unique design vertically stacks 400kV and 220kV GIS, thus minimizing space requirements.
Challenges overcome
AESL braved a number of challenges while laying the line, mainly in surmounting difficult terrain, but these were overcome with the use of technology and innovation. For instance, six towers were constructed in creeks using heavy rigs on floating barges (see photograph). In urban areas, height restrictions in some locations were overcome by adopting special horizontal configuration towers.
Transmission Licence
According to information available with T&D India, Maharashtra Electricity Regulatory Commission (MERC), on January 23, 2021, granted licence to KVTL to operate the transmission system under the build, own, operate and maintain (BOOM) mode. The project was in the making for over ten years before it was awarded to Adani Energy Solutions Ltd (then known as Adani Transmission Ltd) in June 2020, under the tariff-based competitive bidding route. The project entailed investment of around Rs.1,890 crore.
Also read: Adani Energy Bankrolls $1-Billion Mumbai HVDC Link Project
Mumbai HVDC link
Adani Energy Solutions is also developing another important project in Mumbai, which aims at facilitating import of 1,000 mw of power through 80 km of HVDC lines, most of them underground. This massive Rs.7,000-crore, awarded to AESL under the regulated tariff mechanism (RTM) is currently under construction with commissioning likely by March 2025.
Featured photograph sourced from Adani Energy Solutions Ltd.
