Balaju Substation with Single Circuit, located in Kathmandu district's Bagman zone, supplies power to Nagariuna, Swayambhu, Maharjgunj, Bishnumati, BID, Nayabazar, and Dharmasthali. This substation is linked to Iuchatar through 132kV Single Circuit Transmission Line and Chapali via 132kV Double Circuit Transmission Line. It is also linked to the Lainchaur Substation by a 66kV single circuit and the Siuchatar Substation via a dual 66kV transmission system. Trishuli Power Plant will be connected to this Substation by a Double Circuit and will contribute to the Kathmandu Valley's load requirement. In 1967, along with the construction of Trishuli Power House, this substation was created with two numbers of 66/ 11kV, 3*3.75MVA capacity.In 1989, a 132kV transformer bay with 3x15MVA capacity, a 132kV single bay for siuchatar, a double 66KV line bay for siuchatar, and the replacement of an outdated 66/11KV transformer with a new 2*10 MVA power transformer were added, along with a comprehensive GIS system. The two 66/11kV, 10 MVA transformers were replaced in 2009 with new 22.5MVA transformers. The Chapali 132kV Bay for evacuating power from Khimti and Bhotekoshi was built in 2017.