Middle Tamor

73 MW · under construction · on the Tamor River · in Taplejung district. A Sanima Group private IPP stranded pending completion of evacuation infrastructure in Nepal's easternmost Koshi basin development corridor.

Summary

Middle Tamor is a 73 MW run-of-river hydropower project under construction on the Tamor River in Taplejung district, Koshi basin. It is a Sanima Group private IPP stranded pending completion of the Dhunge-Sanghu substation and Basantapur–Dhungesanghu 220 kV evacuation line. The page tracks it as a stranded-generation case study using the NEA licence and Urja Khabar/MoEWRI source set.

Specifications

Sources

• NEA Annual Report FY 2024/25
• Urja Khabar Generation Audit — IPP Generation vs Contracted

Specifications (NEA Licence / MoEWRI data)

The Stranded Asset — Transmission Before Generation

Middle Tamor is explicitly named in the Urja Khabar/MoEWRI report as one of 18 Nepali hydropower projects whose financial viability has been crippled by state-side transmission failures. The wording is stark: "Stranded pending the completion of the Dhunge-Sanghu Substation."

The Basantapur–Dhungesanghu 220 kV transmission line was built specifically to evacuate Middle Tamor's 73 MW. Its 127 towers were erected across eastern Nepal's difficult terrain, and the first circuit was strung by April 2024. The Dhungesanghu substation was finally commissioned on July 6, 2025. But the project had already been waiting for years — generation capacity approved, financed, and built before the evacuation infrastructure that would make it useful.

This is the classic Nepal hydropower timing failure that the Buildability and Stranded Generation pages document: private developers mobilise capital and construction on schedule, only to discover that the public-sector transmission backbone — promised in the same licensing window — is years behind. The financiers who underwrote NPR 7.3 billion in project debt did not underwrite the Nepal Electricity Authority's substation construction programme.

The Tamor Basin — Eastern Frontier

The Tamor River drains the eastern flank of the Koshi basin, rising near the Kanchenjunga massif and flowing south through Taplejung district before joining the Sun Koshi to form the Sapta Koshi. Unlike the crowded Tamakoshi, Khimti, and Likhu corridors to the west — where multiple IPPs compete for the same transmission capacity — the Tamor basin is relatively undeveloped.

Middle Tamor is one of the first large projects in the basin. Its 73 MW places it at a scale comparable to Likhu -2 (55 MW) and Likhu -1 (77 MW), but without the benefit of shared corridor infrastructure or the clustering advantages that the MV Dugar Group exploited in the Likhu Cascade. The Tamor's isolation cuts both ways: fewer competing offtakers on the line, but no neighbouring plants to share the political and financial burden of pushing transmission through.

Sanima Group — Portfolio Developer

Sanima Middle Tamor Hydropower Ltd (formerly Tamor Sanima Energy Pvt. Ltd.) is the project SPV, backed by the Sanima Group — one of Nepal's largest private hydropower developers. Sanima's growing portfolio includes Sanima Mai (22 MW), which has published Q40 design discharge data used in the Q-Design Discharge analysis.

The group's strategy mirrors the cluster-development approach seen elsewhere in Nepali private hydro: establish a track record with a smaller project (Sanima Mai), then scale to larger capacity in a new basin (Middle Tamor). The corporate continuity — same developer, same financing relationships, same regulatory experience — reduces execution risk. But it does not solve the transmission problem. Sanima can build a power station; it cannot build a substation on land it does not own, using a budget it does not control.

The Transmission Problem

The Basantapur–Dhungesanghu 220 kV line that will evacuate Middle Tamor's generation is a single-circuit corridor through eastern Nepal's steepest topography. 127 towers crossing landslide-prone terrain create single-point failure risks that the Likhu Cascade's Khimti–Dhalkebar 220 kV Hydropower Corridor also faces — but with less redundancy and no neighbouring plants to share the outage costs.

For the full structural analysis of how transmission planning failures create systemic IPP risk, see Buildability. For the growing inventory of projects that commissioned into a grid that could not take their power, see Stranded Generation.

Limitations & Controversies

The current page is strongest on licence and stranded-generation context from NEA and MoEWRI disclosures. It does not independently verify current construction progress, final cost, commissioning date, financing closure, or environmental/social compliance status beyond the existing source set. The 54 MW vs 73 MW registry discrepancy is noted but not resolved. Hydrological and transmission risk is documented at the corridor level but not quantified for this specific project site.

See also

• Sanima Mai — 22 MW Sanima Group operating asset with Q40 data
• Q-Design Discharge — design discharge methodology and Sanima Mai data
• Buildability — transmission planning failure as structural IPP risk
• Stranded Generation — the grid evacuation bottleneck problem
• Koshi Basin — basin context and eastern Nepal corridor geography