4th November 2024, Kathmandu
The Chilime–Trishuli 220 kV transmission line, constructed to transmit electricity from hydroelectric projects along the Trishuli River and its tributaries into the national grid, has been completed.
Nepal’s Power Sector Milestone 2024
The transmission line stretches 28 kilometers from the Chilime Hub substation in Thambuchet, Amachodingmo Rural Municipality in Rasuwa, to the Trishuli Three B Hub substation in Kispang Rural Municipality, Nuwakot.
Despite challenging terrain and a tight timeline, including national holiday periods during Dashain and Tihar, employees and contractors worked around the clock to complete the project, as stated by Kulman Ghising, Executive Director of Nepal Electricity Authority (NEA). He noted that this transmission infrastructure was essential for the power generated by 111 MW Rasuwagadhi and 42.5 MW Sanjen, among other hydroelectric projects in Rasuwa, to reach the national grid.
Building the transmission line in geographically demanding and hazardous mountainous areas required tremendous efforts, including transporting materials such as stones, sand, tower components, and water via mules or by hand due to the lack of access roads, steep cliffs, and landslide-prone zones. Despite these challenges, the team completed the line, marking a significant achievement for Nepal’s energy sector. The project faced delays due to adverse weather, land use complications in forested areas, COVID-19 disruptions, and local resistance. The NEA is now moving forward with plans for the Chilime–Kerung cross-border transmission line, designed to enable power trade with neighboring China.
As part of the Chilime–Trishuli 220 kV project, the Chilime Hub and Trishuli Three B Hub substations (rated at 220/132/33 kV) have also been constructed. Power from Trishuli Three B Hub will now feed into the Trishuli–Kathmandu 220 kV line, integrating with the national grid at Matatirtha, Kathmandu. Meanwhile, electricity generated by the Sanjen and Rasuwagadhi projects will reach the Chilime Hub and be routed through the Chilime–Trishuli line into the national network.
A total of 76 towers have been built along the 28-kilometer line, covering altitudes from 680 to 2,600 meters above sea level. Thirty-three of these towers were erected in areas without road access, necessitating the construction of 20 kilometers of new access roads by the NEA’s High-Voltage Grid Department. Construction materials were transported manually and by mule, with helicopters assisting in the installation of two specific towers.
One segment of the line, spanning 1,235 meters from Tiruvillage to Siruchet in Uttargaya Rural Municipality, was completed using drone technology for wire stringing across the Mailungkhola gorge. The Chilime–Mailung segment consists of a 20-kilometer double-circuit line, while the Mailung–Trishuli Three B Hub segment spans 8 kilometers in a multi-circuit configuration. This multi-circuit line is intended to integrate the 216 MW Upper Trishuli–1 hydroelectric project, which is led by Korean companies. The Upper Trishuli–1 project will cover 60% of the costs associated with the multi-circuit line.
The estimated cost of the Chilime–Trishuli project is USD 362.89 million, financed by the Government of Nepal and the NEA with grants from the German Development Bank (KfW) and concessional loans from the European Investment Bank (EIB), an institution established by the European Union.
In 2017, NEA awarded the contract for transmission line and substation construction to China’s Pinggao Group, with implementation beginning in December 2017. The completion of this project is expected to significantly enhance Nepal’s power transmission capacity and help drive economic growth by facilitating uninterrupted power supply across regions.
Key Highlights:
Project Length: 28 kilometers
Transmission Capacity: 220 kV
Total Towers: 76
Altitude Range: 680 to 2,600 meters
Cost: USD 362.89 million
Completion Date: October 2024
For more: Nepal’s Power Sector Milestone