Salient Features
| 1. | General | ||
|---|---|---|---|
| Name of the Project | Tamor Mewa Hydroelectric Project | ||
| Name of River | Tamor and Mewa | ||
| Type of Scheme | Run-of-the-River (RoR) | ||
| District | Taplejung | ||
| Geographical Co-ordinates | |||
| Latitude | 27°20’00’’N, 27°24’08’’N | ||
| Longitude | 87°37’15’’E, 87°40’00’’E | ||
| Nearest Town | Phungling | ||
| Access Road Name | Mechi Highway | ||
| 2. | Organization | ||
| Developer | Spark Hydroelectric Company Limited | ||
| 3. | Hydrology | ||
| Catchment Area | Tamor- 2062 km2 | ||
| Mewa- 574 km2 | |||
| Discharge (at 40%PoE) | Tamor- 95.38 m3/s | ||
| Mewa- 34.18 m3/s | |||
| 4. | Sediment Study | ||
| Average annual Sediment load | 9.41 Million Tons/year | ||
| 5 | Geology | ||
| Regional Geology | Lesser Himalaya, Taplejung window | ||
| Major Rock Types in Headworks | Mewa: Augen Gneiss Tamor: schist, phyllite, quartzite, Granatic Gneiss | ||
| Major Rock Type in Waterways | Mewa: Mica Schist, Tamor: schist, phyllite, and quartzite intercalation | ||
| Major Rock Type in Powerhouse | Granitic Gneiss | ||
| 6. | Structures | ||
| Dam/Weir | Tamor Scheme | Mewa Scheme | |
| Type | Gated Barrage | Concrete Overflow | |
| Length | 85 m | 45 m | |
| Provision of stilling Basin | Simple rectangular | Simple rectangular | |
| Diversion During Construction | |||
| Construction flood | 665 m3/s | 390 m3/s | |
| Diversion Type | Embankment | Embankment | |
| Sluicing | |||
| Number of bays | Spillway Gate: 4 Undersluice Gate: 2 | 2 |
|
| Dimension (B x H) | Spillway: 10m x 7m Undersluice: 10m x 12m | 5m x 4m |
|
| Gate type | Radial | Vertical Lift | |
| Intake Structure | |||
| Type of Intake | Submerged Concrete orifice | Submerged Concrete orifice |
|
| Nos of Opening | 6 | 4 | |
| Size of Intake (B x H) | 5m x 5m | 4m x 2.5m | |
| Gate Type | Vertical Lift Gate | Vertical Lift Gate | |
| Hoisting System | Rope Drum Hoist | Rope Drum Hoist | |
| Trashrack size (B x H) | 5m x 5m | 4m x 2.5m | |
| Clear opening of trash rack | 32 mm | 32 mm | |
| Trash Cleaning Mechanism | TRCM | Manual | |
| Gravel Trap | |||
| Type | RCC Rectangular | ||
| Number of Bays | 3 | ||
| Gravel Trap Size (L x B x H, m) | 32 x 8 x 8 | ||
| Size of Flushing Canal (B x H, m) | 2 x 2 | ||
| Connecting Canal | |||
| Size (L x B x H, m) | 62 x 4 x 8 | ||
| Desander | |||
| Type | Dufour | Dufour | |
| Particle Size to be settled | 0.2 mm | 0.5 mm | |
| Settling Efficiency | 90 % | 90 % | |
| Number of Bays | 3 | 1 | |
| Dimension (L x B x H, m) | 160 x 30 x 12 | 80 x 16 x 5 | |
| Inlet Transition Length | 45 | 15 | |
| Flushing system | Intermittent | Intermittent | |
| Size of flushing channel ( B x H, m) | 1 x 1 | 1 x 1 | |
| Headrace | |||
| Type | Headrace Tunnel | Steel Headrace pipe and Headrace Tunnel | |
| Material | Concrete and shotcrete lined | Steel Pipe and shotcrete lined | |
| Length | 4.78 km | 306 m Pipe and 2616 m Tunnel | |
| Dimension | 7m dia. Horseshoe | Pipe: 3m dia. circular | |
| Tunnel: 4.05m dia. inverted D | |||
| Surge Shaft | |||
| Type | Restricted orifice | ||
| Internal Diameter | 15 m | ||
| Height | 58m | ||
| Penstock /Pressure Shaft | |||
| Type | Underground | Surface | |
| Material | Steel lined | Steel pipe | |
| Internal Diameter | 5.75m | 3.0m | |
| Length | 155m | 120m | |
| Steel Thickness | 20 - 36mm | 12mm | |
| Powerhouse | |||
| Type | Underground | ||
| Size (L x B x H,m ) | 80 x 20 x 29 | ||
| Overhead hoisting type | EOT Crane | ||
| Overhead hoist capacity | 140 Ton | ||
| Support type | Shotcrete and rockbolt | ||
| Tailrace | |||
| Type | Underground | ||
| Number | 1 | ||
| Dimension | 7.6m dia. Horseshoe | ||
| Length | 270 m | ||
| 7. | Turbine | ||
| Type | Vertical axis Francis | ||
| Number | 3 | ||
| Rated Output Capacity per unit | 44.00 MW | ||
| Gross Head | 124.50 m | ||
| Discharge per Unit | 42 m3/s | ||
| Efficiency | 92% | ||
| 8. | Generator | ||
| Type | Synchronous | ||
| Synchronous Speed | 300 rpm | ||
| Rated Output Capacity per Unit | 50.30 MVA | ||
| Power Factor | 0.85 over-excited | ||
| Generation Voltage | 11 kV | ||
| Frequency | 50 Hz | ||
| No of Units | 3 | ||
| Excitation System | Static with microprocessor based digital AVR | ||
| Efficiency | 97% | ||
| 9. | Transformer | ||
| Type | Indoor type single phase | ||
| Rated Capacity | 17 MVA each | ||
| Voltage Ratio | 220/√3/11kV | ||
| No of Units | 10 (including 1 spare) | ||
| Vector Group | Ynd5 solidly earthed | ||
| Frequency | 50 Hz | ||
| Efficiency | 99% | ||
| 10. | Transmission Line | ||
| Voltage Level | 220 kV double circuit | ||
| Length | 6.3 km | ||
| Conductor Type | 2*BISON | ||
| From | PH switchyard | ||
| To | Dhungesaghu Substation | ||
| 11. | Power and Energy | ||
| Design Discharge | 129.56 m3/s | ||
| Gross head | 124.5 m | ||
| Installed Capacity | 128 MW | ||
| Total Energy | 719.11 GWh |