Salient Features
Tallo Likhu Jalvidhyut Aayojana-TLJA (28.1 MW) is owned and being developed by Swet Ganga Hydropower & Construction Limited.
The project is a Run of River (RoR) type with its headworks located on the right bank of Likhu River at Likhu Tamakoshi Rural Municipality of Ramechhap District, Bagmati Province and the left bank of weir lies of Likhu Rural Municipality of Okhaldhunga District, Province 1 of Nepal.
The entire project area is located in Saipu-2 and Bijulikot-4 of Likhu Tamakoshi Rural Municipality. Geographically, the project area is located between Longitudes 86015’38” E to 86013’17” E and latitude 27025’50” N to 27022’47” N. Geologically, the project area belongs to the Lesser Himalayas . The project utilizes design discharge of 29.75 m3/s and gross head of 118 m resulting into an installed capacity of 28.1 MW.
The annual energy generation is 170.84 GWh, where the dry season energy contributes 30.94 GWh and wet season energy contributes139.89 GWh.
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GENERAL |
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| Name of the project | Lower Likhu Hydropower Project |
| Developer | Swet Ganga Hydropower & Construction Ltd. |
| Name of the River | Likhu River |
| Type of scheme | Run-of-River |
| Project location | Saipu and Bijulikot VDC's of Ramechhap District and Tarkerabari of Okhaldunga District |
| Zone | Janakpur Zone |
| Development region | Central Development Region |
| Nearest road-head | Up to Sirise at Headworks |
| Up to Ratamate at Powerhouse | |
| Climate | Sub-tropical |
| Average temperature | Maximum : 36.3 0C in May |
| Minimum : 4.30C in January | |
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GEOGRAPHICAL COORDINATES |
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| Latitude | 270 22’ 47” N to 270 25’ 50” N (Generation license) |
| Longitude | 860 13’ 17” E to 860 15’ 38” E (Generation license) |
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HYDRO-METEOROLOGY |
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| Average annual rainfall | 1796 mm |
| Catchment area at intake | 717.54 km2 |
| Annual mean flow | 42.29 m3/s |
| Maximum mean monthly flow | 125.12 m3/s |
| Minimum mean monthly flow | 8.84 m3/s |
| Design discharge | 29.75 m3/s |
| Flood discharge | 737 m3/s |
| WEIR | |
| Type | Concrete ogee |
| Crest elevation | 742.00 m amsl |
| Length | 53 m |
| Max Dam height (from existing ground) | 5.5 m |
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UNDERSLUICE |
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| Type | Radial Gate Mechanism |
| Number of bays | 2 |
| Size, B x H | 6.0 x 6.0 m (each) |
| Sill level | 734.0 m amsl |
| INTAKE | |
| Type | Side intake |
| No. of orifice | 4 |
| Size, B x H | 3.5 x 2.8 m (each opening) |
| Intake sill level | 738.00 m amsl |
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GRAVEL TRAP AND GRAVEL FLUSHING |
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| Type | Surface |
| Number of bays | 2 |
| Size, L x B x H | 11.0 x 8.0 x 7.4 m (each) |
| Size of Flushing pipe | 1.5 m dia. (each) |
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APPROACH CULVERT |
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| Type | Pressurized culvert |
| Number of branches | 4 |
| Size, B x H (m) | 2.4 x 2.5 m (each) |
| Length | 83 m (Branch 1st), 68.50 m (Branch 2nd) |
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SETTLING BASIN |
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| Type | Conventional |
| Numbers | 2 |
| Size L x B x H | 65 m x 6.7 m x 8.0 m (each basin) |
| Length of inlet transition (m) | 51.50 m |
| Particle size to be settled (mm) | 0.2 |
| Flushing system | Intermittent |
| Size of Flushing canal, B x H (m) | 2.0 x 1.5 m (each) |
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HEADRACE PIPE |
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| Pipe Material | Mild Steel |
| Internal Diameter (m) | 3.75 |
| Length | 304 m |
| HEADRACE TUNNEL | |
| Type of Flow | Pressurized |
| Geometry | Inverted D-shape |
| Length (m) | 4965 |
| Size (without payline) | 4.9 x 4.9 m |
| KHOLSI CROSSING (SYPHON) | |
| SETI KHOLSI CROSSING | |
| Length | 218.7 m |
| Internal Diameter of pipe (m) | 3.75 m |
| POKU KHOLSI CROSSING | |
| Length | 243.5 m |
| Internal Diameter of pipe (m) | 3.75 m |
| SURGE TANK | |
| Height | 46.5 m (from invert) |
| Diameter | 12 m |
| PENSTOCK | |
| Pipe Material | Mild Steel |
| Length | 191 m |
| Diameter | 3.75 / 2.65 m |
| POWERHOUSE | |
| Type | Semi-surface |
| Length x Width x Height | 33.3 m x 21.7 m x 27 m |
| Turbine setting level | 623.00 m amsl (center line) |
| TAILRACE | |
| Type | Box culvert |
| Length | 210 m |
| Height | 3.35 m |
| Width | 4 m |
| TURBINE | |
| Type | Francis, vertical axis |
| Numbers | 2 |
| Rated output capacity per unit | 15 MW |
| Efficiency | 91.00% |
| GOVERNOR | |
| Type | Electronic PID control |
| Adjustment for speed drop | Between 0 to 5% |
| GENERATOR | |
| Type | Three phase, Synchronous |
| No of units | 2 |
| Power factor | 0.85 |
| Voltage | 11 kV |
| Frequency | 50 Hz |
| Excitation system | Brushless |
| Efficiency | 97% |
| TRANSFORMER | |
| Type | Three phase, Oil immersed |
| No of units | 2 |
| Frequency | 50 Hz |
| Rated output capacity per unit | 17 MVA |
| Voltage ratio | 11 kV/ 132 kV |
| Efficiency | 99% |
| SWITCHYARD AND TRANSMISSION LINE | |
| Switchyard type | Outdoor, conventional |
| Transmission line length | 23 km |
| Voltage level and circuit | 132 and single circuit |
| Conductor | ACSR “WOLF” |
| POWER AND ENERGY | |
| Gross head | 118.0 m |
| Net head at design flow | Approx. 112.64 m |
| Installed capacity | 28.1 MW |
| Dry energy | 30.94 GWh |
| Wet energy | 139.89 GWh |
| Average annual gross energy | 170.84 GWh |