Upper Trishuli - 3B
Trishuli Jal Vidhyut Company Limited (TJVCL) is planning to develop Upper Trishuli 3B Hydropower Project (UT3BHEP) with installed capacity of 37 MW located in Nuwakot and Rashuwa District. UT3BHEP is a run-off-river (ROR) type cascade project of Upper Trishuli 3A HEP (60 MW) which lies in the Trishuli River.
Salient Features
Project Location | |||
Province | 3 | ||
Zone / District | Bagmati / Nuwakot and Rasuwa | ||
Intake Site | Kispang Rural Municipality (Nuwakot) and Uttargaya Rural Municipality (Rasuwa) | ||
Powerhouse Site | Kispang Rural Municipality (Nuwakot) | ||
General | |||
Name of River | Trishuli River | ||
Nearest Town | Trishuli Bazar | ||
Type of Scheme | Run-of-River | ||
Maximum Gross Head | 90.0 m | ||
Net Head | 85.37 m | ||
Installed Capacity | 37 MW | ||
Average Annual Energy | 304.78 GWh | ||
Average Annual Energy after Outage | 292.59 GWh | ||
Hydrology | |||
Catchment Area | 4577 km2 | ||
Mean Annual Discharge | 192 m3/sec | ||
Design Discharge (at Q70% PoE) | 51 m3/sec (Tailrace water of Upper Trishuli 3A) | ||
Riparian Release | 3.84 m3/sec | ||
1000 Yrs Flood Discharge | 2718 m3/sec | ||
Headpond (Connected to UT3A Tailrace Pond) | |||
Size | 29 m x 5.2 m to 11.2 m x 7.35 m to 16.8 m | ||
Lowest Bed Level | EL. 712.20 m | ||
Intake | |||
Type | Bellmouth | ||
Intake Invert Level | EL. 714.90 m | ||
Submergence Depth | 6 m | ||
Approach Pressure Conduit | |||
Type | Box Culvert and Steel Pipe embedded in concrete | ||
Box Culvert Length | 276 m | ||
Box Culvert Size | 5.1 m x 5.1 m | ||
Steel Pipe Length | 40 m | ||
Diameter of Pipe | 5.10 m | ||
Headrace Tunnel | |||
Shape | Circular for concrete lined and horseshoe for shotcrete lined section | ||
Length | 3666 m | ||
Diameter | 5.20 m for concrete lined and 6.0 m for shotcrete lined | ||
Portal Invert Level | EL. 714.90 m | ||
Adit Tunnel | |||
Shape | Inverted D | ||
No. of Adit Tunnels | 2 | ||
Length of Adit-1 Tunnel | 463.6 m | ||
Diameter of Adit-1 Tunnel | 4.0 m | ||
Length of Adit-2 Tunnel | 100 m (Indicative) | ||
Diameter of Adit-2 Tunnel | 5.0 m (Indicative) | ||
Surge Tank | |||
Type | Restricted Orifice | ||
Diameter of Tank | 15.0 m | ||
Height | 24.6 m | ||
Throttling Diameter | 2.0 m | ||
Level of Surge Tank Crown | EL. 736.3 m | ||
Bottom Elevation of Surge Tank | EL. 711.7m | ||
Pressure Tunnel After Penstock Stoplog | |||
Section | Circular | ||
Diameter | 4.20 m | ||
Length | 33 m (including transition from square to circular pressure tunnel) | ||
Concrete Lining Thickness | 300 mm | ||
Pipe Shell Thickness | 14 mm | ||
Inclined Shaft | |||
Type | Circular | ||
Diameter | 4.20 m | ||
Length | 100 m | ||
Lining Thickness | 300 mm (Concrete) & 100 mm (Shotcrete) | ||
Pipe Shell Thickness | 14 mm | ||
Pressure Tunnel After Inclined Shaft | |||
Type | Circular | ||
Diameter | 4.20 m | ||
Length | 24.0 m | ||
Lining Thickness | 300 mm | ||
Pipe Shell Thickness | 14 mm | ||
Penstock After Bifurcation (Penstock Manifold) | |||
Type | Circular | ||
Diameter | 3.0 m | ||
Length | 15.0 m (including transition) | ||
Steel Lining | 14.0 mm | ||
Powerhouse | |||
Type | Surface | ||
Size (L x B x H) | 37.60 m x 14 m x 28.2 m | ||
Center line of Turbine | EL. 634.5 m | ||
Tailrace Conduit | |||
Type | RCC, Conduit | ||
Length | 129.6 m | ||
Size (B x H) | 6.7 m x 5.0 m | ||
Tail Water Level | EL. 637.5 m | ||
Turbine | |||
Type | Vertical Axis, Francis | ||
No. of Units | Two (2) | ||
Rated Output Capacity per unit | 19.1 MW | ||
Efficiency | 92.5 % | ||
Governor | |||
Type | Electronic with PID Control | ||
Adjustment for Speed Drop | Between 0 to 5 % | ||
Generator | |||
Type | Synchronous, 3 Phase | ||
No. of Units | Two (2) | ||
Rated Output Capacity per Unit | 22 MVA | ||
Power Factor | 0.85 | ||
Rated Voltage | 11 kV | ||
Frequency | 50 Hz. | ||
Rated Speed | 375 rpm | ||
Excitation System | Static | ||
Efficiency | 97% | ||
Transformer | |||
Type | Outdoor, Oil Immersed, 3 Phase, ONAN | ||
No. of Units | Two (2) | ||
Rated Capacity per Unit | 23 MVA | ||
Frequency | 50 Hz. | ||
Vector Group | YNd 5 | ||
Voltage Ratio | 11 kV/ 132 kV | ||
Efficiency | 99% | ||
Transmission Line | |||
Voltage Level | 132 kV, Single Circuit | ||
Length | 3 km | ||
Conductor | ACSR "BEAR" | ||
From | Powerhouse | ||
To | Proposed Trishuli 3B Hub | ||
Construction Period | 36 months |