Birgunj substation, located in the Parsa district Narayani zone, supplies power to Pokhariya, Raxaul, Kalaiya, and Birgunj city. Birgunj and Hetauda substations are linked by a 66kV Double Circuit Transmission Line. Birgunj Substation opened in 1972 with a capacity of 66/11kV, 1.5MVA, which was later increased to 6MVA. In 1989, the waste system received a new Transformer Bay with two nos. of 66/33kV, 12.5MVA. The original 6MVA transformer was replaced in 2015 with two 66/111N, 7.5MVA capacity transformers, which were then upgraded to two 66/11kV, 15MVA capacity transformers. Because of the severe voltage problem and significant demand for reactive VAR in this area, 33kV, 5MVAR, and 11kV, 5MVAR Capacitor Banks have been installed.Because of the increased need for industrial load in this region, additional 33kV, 10MVAR, and 11kV, 10MVAR Capacitor Banks with new bays were constructed in April 2009. In 2014, the existing 66/11kV, 2x15MVA was upgraded to 2x30 MVA. In 2019, one of the 66/33 KV,12.5 MVA units was upgraded to 30 MVA.