Power Grid Corporation of India Limited (Powergrid) has commissioned the 400/220 kV Mariani substation in Jorhat district of Assam. This substation is the first 400 kV substation in upper Assam and will serve as a key station for catering to the growth of power in upper Assam, Nagaland, Manipur and the entire north-eastern region (NER) of the country, while also enhancing the reliability of the southern part of the NER grid. Powergrid was entrusted with the project under the North Eastern Region Strengthening Scheme VI. Its scope of work encompasses the installation of 2×400/220 kV, 500 MVA transformers and 2×420 kV, 125 MVAR bus reactors, along with other associated bays, at Mariani. In the first phase, one 400/220 kV 500 MVA transformer and one 420 kV, 125 MVAR bus reactor and associated bays have been commissioned.