The Ankhu Khola Hydropower Project is located in the Dhading District, about 132 kilometers from Kathmandu. It harnesses the Ankhu Khola, a significant tributary of the Budhi Gandaki River. The river’s catchment area is approximately 633 square kilometers, with an average annual water flow of 58.38 cubic meters per second (cumecs). The project is designed to handle a water flow of 34.5 cumecs, which is sufficient to generate electricity with a high probability of continuous operation.
Project Location:
The project is situated between the coordinates of 28°00’00” to 28°00’57” North latitude and 84°54’00” to 84°55’32” East longitude. The intake structure, where water is collected, is located 70 meters downstream from the existing Ankhu Khola Suspension Bridge. The power house, where electricity is generated, is proposed at Rigna Bazaar on the right bank of the river in Sisneri Khet. The project is expected to produce an average of 46.408 GWh (gigawatt hours) of electricity annually. The generated power will be transmitted through a 12 km long transmission line to the Nepal Electricity Authority (NEA) substation at Dhading Besi.
Background:
The Ankhu Khola Hydropower Company Ltd. (AKHC) has contracted Welink Associates (P) Ltd., in association with Public Consulting Engineers (P) Ltd., to conduct a feasibility study for the Ankhu Khola Hydropower Project in Dhading District.
Objectives and Scope:
The main goal of the feasibility study was to identify the best site for developing a small hydropower project on the Ankhu Khola. The study aimed to confirm the technical and economic viability of connecting the project to the national power grid. It involved selecting and arranging the structures, optimizing the design, and determining the ideal scale for development. The study also included a financial analysis of the project’s costs and benefits.
Capacity and Contribution to the Nation:
Initially, the project was planned to have a capacity of 7.0 MW, but it was later upgraded to 8.4 MW. The project is designed to operate with a water flow of 34.50 cubic meters per second. The electricity generated, 8.4 MW, will contribute to the national power supply.
Chart
Silent Feature of the Feature
Salient Features
A. Location
- Latitude: 28°00’00” to 28°00’57” N
- Longitude: 84°54’00” to 84°55’32” E
- District: Dhading
- VDC: Salyankot and Marpak
B. Hydrology
- Catchment Area: 633 km²
- Snow-Covered Catchment Area: 24 km²
- 40th Percentile Flow: 39.86 m³/s
- Design Flood at Intake: 1213 m³/s (100-year flood)
Head Works:
- Diversion Weir (Gated):
- Type: Concrete gravity type
- Crest Length: 41.00 m
- Ponding Level: 570.40 m
- Approach Canal:
- Length: 85 m
- Culvert Slope: 1 in 500, 1 in 1000
- Size (Width x Depth): 6.00 m x 4.65 m
- Headrace Steel Pipe:
- Type: Buried steel pipe
- Diameter: 4 m
- Thickness: 12 mm
- Length: 820 m
- Slope: 1:1,000
- Penstock:
- Type: Exposed, supported/anchored
- Total Length: 150 m (3 pipes x 50 m each)
- Internal Diameter: 2,500 mm
- Thickness: 12 mm
- Number of Pipes: 3
- Power House:
- Type: Semi-underground
- Size: 48 m x 18 m
- Height: 15 m from floor level
- River Training Work:
- Type: Earthen bond with gabion mattress
- Length: 950 m
- Width: 3 m at top, with 1:1 side slope
- Height: 3 m
Power Generation:
- Design Discharge: 34.5 m³/s
- Gross Head: 30.84 m
- Net Head at Design Flow: 27.84 m
- Installed Capacity: 8.4 MW
- Dry Season Energy: 6.737 GWh/year
- Wet Season Energy: 39.671 GWh/year
- Total Energy: 46.408 GWh/year
Access Road:
- Total Length: 7 km
- Road Width with Shoulders: 4.0 m
- Maximum Gradient: 10%
- Cross Slope: 4%
- Design Speed: 30 km/h
- Road Surface: 300 mm thick gravel
Additional Structures:
- Intake:
- Type: Orifice type
- Still Level: 568 m
- Number of Intakes: 5
- Settling Basin:
- Length of Inlet Transition: 10 m
- Length of Settling Zone: 60 m
- Chamber Width: 10 m
- Surge Tank:
- Type: RCC
- Diameter: 10 m
- Height: 15 m
- Number of Chambers: 3
- Settling Basin Trapping Efficiency: 90% for 0.20 mm particles
- Tailrace Canal:
- Type: Trapezoidal (open flow)
- Width: 10 m for the first 100 m, 20 m thereafter
- Side Slope: 1 vertical : 2 horizontal
- Tail Water Level: 539.652 m from MSL
- Length: 980 m
Mechanical and Electrical:
- Turbine:
- Type: Francis (Vertical)
- Number of Units: 3
- Capacity: 2.8 MW x 3 = 8.4 MW
- Transmission Line:
- Length: 12 km
- Type: 33 kV
- Generator:
- Type: Salient pole, synchronous
- Number of Units: 3
- Rating: 3000 kVA
- Power Factor: 0.85 (overexcited)
- Frequency: 50 Hz
- Rated Speed: 300 rpm
- Rated Voltage: 6.6 kV
Capital Structure
- Authorized Capital: NPR 1,150,000,000
- Issued Capital: NPR 800,000,000
- Paid-up Capital: NPR 800,000,000
- Promoter Shareholding: 75%
- Public Shareholding: 25%