Salient Features Ankhu Khola Hydropower Projects 42.9 MW
The principle features of the Ankhu Khola Hydropower Project (AKHPP) are summarized below.
| Name of the project | : | Ankhu Khola Hydropower Project |
| Type | : | Run-of-River |
| Location | : | Ri VDC of Dhading District |
| Longitude | : | 28o04’00”N and 28o07’00”N |
| Latitude | : | 84o58’35”E and 85o01’04”E |
| Hydrology | ||
| Catchment area at headwork site | : | 427.55 km2 |
| Mean Annual Precipitation | : | 1847.76 mm |
| Mean Annual Flow | : | 23.65 m3/s |
| Design Flood (1 in 100 years) | : | 666.44 m3/s |
| Power Development | ||
| Type of Power Generation | : | Run-of-river |
| Design Discharge (Q37%) | : | 23.65 m3/s |
| Minimum Flow | : | 5.04 m3/s |
| Full Supply Level | : | EL 894.16 m |
| Tail Water Level | : | EL 677.77 m |
| Gross Turbine Head | : | 216.40m |
| Net Turbine Head | : | 209.27 m |
| Installed Capacity | : | 42.9 MW |
| Average Annual Energy | : | 230.91 GWh |
| Annual Wet Energy | : | 200.13GWh |
| Annual Dry Energy | : | 30.77 GWh |
| Weir | ||
| Type | : | Ogee Shaped, Overflow Type |
| Length
Height |
:
: |
35 m
4.75 m |
| Crest Level of Weir | : | EL 894.41m |
| Under Sluice | ||
| Design Discharge | : | 133.29 m3/s |
| Invert level near gate | : | 889.65 masl |
| No. | : | 2 Nos. |
| Width
Height |
:
: |
2.5 m
5 m |
| Intake | ||
| Intake Type | : | Side Intake |
| No. | : | 4 Nos. |
| Size (W×D) | : | (3.4 × 2.3) m |
| Type | : | Surface/Hopper Shaped |
| Settling Criteria | : | 90% of ≥ 2mm |
| No. of Basin | : | 2 Nos. |
| Size of each Gravel Trap (L × B × D) | : | (17.5 × 7.8 × 4.0) m |
| Length of Spillway | : | 16.95 m |
| Length of Flushing Canal | : | 92.53 m |
| Flushing opening size (W×D) | : | (0.8 × 0.9) m |
| Flushing canal (W×D) | : | Surface/Rectangular |
| Approach Tunnel | ||
| Type | : | Underground/ Rectangular |
| No. | : | 2 Nos. |
| Size (W×D) | : | (3.0 × 2.3) m |
| Length | : | 57.50 m |
| Settling Basin | ||
| Type | : | Underground/Hopper |
| Settling Criteria | : | 90% of ≥ 0.2 mm |
| No. of Chamber | : | 2 Nos. |
| Size (L × W) | : | (116.7 × 14) m |
| Total Depth | : | 7.74 m |
| Inlet Transition Length | : | 27.75 m |
| Forebay Size (L×B × H) | : | (16.36 m x 10. M × 10.9 m) |
| Normal Water Level at Forebay | : | 893.87 masl |
| Spillway Length | : | 16.46 m |
| Flushing Canal after Flushing opening (W × D) | : | (0.9 × 1.0) m |
| Flushing Canal after conv. (under pressure) (W × D) | : | (1.75 × 1.0) m |
| Flushing Canal before conv. (under gravity) (W × D) | : | (3.5 × 1.4) m |
| Accelerating Tunnel | ||
| Shape | : | Inverted D-Shaped |
| Tunnel Size (W×D) | : | 2.0 m × 2.0 m |
| Length | : | 44 m |
| Type of Lining | : | Shotcrete, Concrete |
| Headrace Tunnel | ||
| Tunnel Type | : | Inverted D-Shaped |
| Tunnel Length | : | 5262 m |
| Tunnel Size (W×D) | : | 4.0 m × (2.0+2.0) m |
| Type of Lining | : | Shotcrete, Concrete |
| Surge Tank | ||
| Type | : | Non Spilling Type |
| Shape | : | Circular |
| Diameter | : | 10.30 m |
| Height | : | 39 m |
| Upsurge Elevation | : | 908.32 m |
| Down Surge Elevation | : | 878.56 m |
| Normal Water Level in Surge Tank | : | 890.67 m |
| Static Water Level in Surge Tank | : | 893.94 m |
| Penstock | ||
| Penstock Type | : | Surface and Underground (Steel Penstock) |
| Length | : | 420 m |
| Inner diameter
No. of Branches Dia of Each Branch |
:
: : |
3.2 m
3 Nos 12-32 mm |
| Power House | ||
| Type of Powerhouse | : | Semi Surface |
| Size (L x B x H) | : | 63.0 m × 20.6 m × 13.5 m |
| Tail Water Level | EL 677.77 m | |
| Turbine | ||
| Turbine Type | : | Francis |
| Rated Discharge | : | 7.88 m3/s |
| Number of Turbine | : | 3 Nos. |
| Rated Output | : | 3 x 14.30 MW |
| Rated Net Head | : | 209.27 m |
| Efficiency of turbine | : | 92% |
| Generator | ||
| Number of units | : | 3 Nos. |
| Rated output | : | 3 × 17.87 MVA |
| Rated speed | : | 750 rpm |
| Rated frequency | : | 50 Hz |
| Type | : | Synchronous with brushless
excitation system, water cooled |
| Efficiency | : | 97 % |
| Transformer | ||
| Rating | : | 3 × 17.87 MVA |
| Primary Voltage | : | 11 kV |
| Secondary Voltage | : | 132 kV |
| Frequency | : | 50 Hz |
| Efficiency of transformer | : | 99 % |
| Efficiency | ||
| Overall Efficiency Adopted | : | 88.3 % |
| Tailrace Canal | ||
| Size (B x H) | : | 3.8 m × 6.15/2.85 m |
| Length | : | 103.78 m |
| Longitudinal Slope | : | 1 in 1000 |
| Tail Water Level | : | 677.77 masl |
| Transmission Line | ||
| Transmission Line | : | About 30 km, 132 kV single circuit to
Proposed Trishuli “3B” substation |
| Construction Period | : | 4 Years |
