Upgradation of new Mariani substation by POWERGRID
New Mariani Substation was commissioned in March 2013 in Jorhat District of Assam as a 220KV Switching station with 20MVAR reactive power compensation capacity.
In 2020-21, New Marini Substation has been upgraded to a 400/220 KV substation with 2X500MVA Transformation capacity, 2X125MVAR Reactive power compensation along with other associated bays under NERSS-VI Project.
All the bays & additional 400 kV D/C line section for up-gradation of the Misa-New Mariani line from 220 kV to 400 kV level are now under commercial operation.
The said upgradation was necessitated for establishing connectivity at 400KV voltage level between 400KV Misa Substation, 400KV New Mariani Substation & 400KV Kohima Substation (which is a TBCB asset i.e. 400KV New Mariani- Kohima Transmission system)
This substation is the first-ever 400KV Substation in upper Assam & shall serve as a key station for catering to the growth of power in upper Assam, Nagaland & Manipur & the entire North Eastern Region of the country as well as enhance the reliability of the Southern Part of NER Grid.
The project has been commissioned matching with the commissioning of the associated TBCB transmission asset (i.e. within December/2020) thereby avoiding heavy penalties to be imposed by Statutory authorities (in case of delay), despite various limitations in the wake of the covid 19 pandemic, poor soil condition in Substation working area and extended Rain & inundation of worksite, etc.