Dordi Khola Hydropower Project (27 MW)
Technical Summary
Dordi Khola Hydropower Project is a Run-of-River type hydroelectric project with generating capacity of 27 MW. The project is being developed by Himalayan Power Partner Ltd. (HPPL) Kathmandu, Nepal. IME Group and NRN Infrastructure & Development Ltd. to develop Dordi Khola This is the first corporate investment of Non Resident Nepalese (NRN) in Nepal.
Feasibility Study of the Project was completed in March 2010. Detail Project Report (DPR) is prepared by international consultant Entura Hydro Tasmania.
The whole project area lies in Chiti, Dhodeni and Bansar VDCs in Lamjung district in western Nepal. It is connected from Kathmandu by 170 km all weather metallic roads up to Udipur at Dumre-Beshisahar Road. A fair weather road from Udipur to Hile passes near by the headworks site (12 km). Initial Environmental Examination (IEE) study was completed and approved from the Ministry of Energy in September 2010. About 50 ropani out of 150 ropani private land needed for different project components have been purchased. The negotiations for the purchase of rest of private land are on the process and planned to complete by February 2014. The generated power will be evacuated to Integrated Nepal Power System (INPS) through a 132 kV single circuit Transmission Line (TL) up to the proposed Udipur Hub of Nepal Electricity Authority (NEA). Length of TL will be 1.2 km.
The connection agreement with the Grid Department of NEA for the power evacuation was concluded on 2067/03/23 (July 7,2010). The company acquired generation license in July 7, 2011 from the ministry of Energy for the period of 35 years including one year for Power Purchase Agreement and financial closure and another four years of construction period.
Facility agreement to provide Term Loan of amount NPR 3,170 million, 75% of total project cost including IDC, NPR 4,235 million, was concluded with Bank Consortium led by Prime Commercial Bank Ltd. on 7 November 2013.Financial progress up to July, 2019 is NPR 3,002 million (70.89%).HPPL has completed the process of IPO after allotting equity shares worth NPR 319.625 million (30% of equity capital NPR 1, 065 million) to general public including project effected area people and company employees in Shrawan 2074. The public shares of HPPL have been listed in Nepal Stock Exchange & being trading in Secondary Market.
The Power Purchase Agreement (PPA) between the company and Nepal Electricity Authority (NEA) was concluded for the period of 34 years (including 4 years for construction) on June 15, 2012 @ NRs. 8.40/kWh for dry energy and NRs. 4.80/ kWh for wet energy and will be escalated @ 3% (compound) for nine years.
Developer | Himalayan Power Partner Limited |
Location | Chiti,Dhodeni, & Bansar VDC of Lamjung Distrcit |
Installed Capacity | 27 MW |
Design Discharge | 15.28 m3/s |
Survey License Issued | 26 May,2005 |
Grid Connection Agreement | 7th July,2010 |
Generation License Obtained | 7th July,2011 |
PPA Signed | 15th Jun2,2012 |
Facility Agreement Signed | 7th Novemeber,2013 |
Contract of Main Civil Works | April,2014 |
Required Commercial Date of Operation | 12 April,2020 |
Dry Energy | 21.367 GWh |
Wet Energy | 120.952 GWh |
Average Annual Energy | 142.319 GWH |
Construction Works Started | April,2014 |
Total Project cost | NPR 4,498 Million |
Salient Features of the Project:
Location | |
Country | Nepal |
District | Lamjung |
Development Region | Western |
Location of Intake and Project site | Chiti VDC |
Nearest Airport | Pokhara |
Geographical Co-ordinates of Project Area | |
Longitude | 84° 26’E to 84° 28’30”E |
Latitude | 28°10’ N to 28°13’ 32”N |
Hydrology | |
River/Stream | Dordi-Khola |
Catchment area at Diversion site | 277 km2 |
Design Discharge | 15.28 m3/s |
Design Flood at diversion site (100 year return period) | 614 m3/s |
Design Flood at Powerhouse site (1000 year return period) | 3251 m3/s |
River Diversion Arrangement | |
1 in 20 years dry season design flood | 27.24 m3/s |
Top of coffer dam at upstream | El. 762.0 m |
Top of coffer dam at downstream | El. 756.0 m |
Diversion Structure | |
Type | Ogee Type weir, free over flow with under sluice bays |
Average river bed level | El. 758.0 m |
Bridge deck level | El. 768.0 m |
Width of diversion structure | 55 m |
Highest flood level | El. 767.75 m |
Full supply level | El. 764.50 m |
Weir | |
Crest elevation of overflow weir | El. 764.75 m |
Width of overflow weir section | 41.2 m |
Under Sluice Bay | |
No. of under sluice bays | 2 |
Width of each bay | 4.25 m |
Thickness of pier | 1.5 m |
Crest level of under sluice bay | El. 758.0 m |
Clear width of under sluice bays | 8.5 m |
Type and height of gate | Vertical gates, 3 m high. |
Energy Dissipation System | Hydraulic Jump Type Stilling Basin |
Length of stilling basin from toe of sloping glacis | 25 m |
Total width of basin | 49.725 m |
Cistern level | El. 754.0 m |
End Sill Level | El. 757.0 m |
Intake Structure | Side Intake |
Type | 4.75 m (W) x 4.0 m (H) |
Track rack size | |
Numbers of trash rack | 2 |
Intake diversion flow (including 20% flushing discharge) | 18.33 m3/s |
Intake size | Two bays; each 2.25 m (W) x 2.7 m (H) |
Invert level of Intake | El. 760.50 m |
Intake stop log | 1 no. Vertical lift gate (2.25 m x 2.7 m) |
Intake service gate | 2 nos. Vertical lift gate (2.25 m x 2.7 m) |
Feeder Pipe | |
Type | Circular steel |
Numbers | 2 |
Size | 2.25 m Dia. |
Length | 131.30 m & 140.10 m |
Desilting Basin | |
Type | Hopper Type |
Numbers of chambers | 2 nos |
Size of particles to be removed | 0.2 mm and above |
Dimension (L x B x H) | 60 m x 8.5 m x 8.0 m |
Design discharge | 18.33 m3/s |
Flow through velocity | 0.26 m/s |
Silt Flushing Pipe | |
Type | Circular |
Dia | 0.9 m |
Total length | 100 m |
Water Conductor Pipe | |
Type | Steel Pipe |
Size | 2.65 m dia |
Total length | 3282 m |
Head Race Tunnel (Concrete Lined) | |
Type & shape | Underground, D-shaped |
Dia | 3.3 m |
Total Length | 2661.67 m |
Steel Lined Tunnel | |
Type & shape | Underground, circular |
Dia | 2.65 m u/s of HRT, 2.3 m d/s of HRT |
Total length | 25 m, 82 m respectively |
Surge Shaft | |
Type | Restricted orifice type |
Height | 45 m |
Dia | 7 m |
Orifice size | 1.3 m dia, circular |
Top of surge shaft | El. 780.0 m |
Maximum upsurge level | El. 778.06 m |
Minimum down surge level | El. 746.39 m |
Valve House | |
Type | Surface |
Number | 1 |
Size ( L x W x H) | 16 m x 9.5 m x 12 m |
Type of valve | Buttery valve |
Diameter of valve | 2.3 m |
Penstock | |
Type | Surface and Buried Penstock |
Nos. | One no. starting from outlet portal and trifurcating before Power House. |
Diameter | 2.3 m, circular shaped |
Liner thickness | 10 mm to 20 mm |
Length | 830.5 m |
Length of penstock after trifurcation | 163.8 m |
Branch penstock | Circular, 1.3 m diameter each |
Power House | |
Type | Surface |
Gross Head | 214 m |
Rated Head | 203.32 m |
Design discharge | 15.28 m3/s |
Normal Tail water Level | El. 552.0 m |
Center line of penstock | El. 550.45 m |
Size of Powerhouse at machine floor | 44.225 m (L) x 15.0 m (W) x 31.25 m (H) |
Tail Race Channel | |
Type | RCC Box culvert |
Length | 333.66 m |
Size | 3.5 m x 2.5 m |
Normal tail water level | El. 552 m |
Switchyard | |
Size | 30 m x 40 m |
Voltage level | 132 kVA |
Turbine | |
Turbine Type | Horizontal axis Francis |
Number | 3 |
Rated Capacity of each turbine | 9.3 MW |
Governor | |
Type | Electro-Hydraulic |
Generator | |
Generator Type | Synchronous three phase |
Number | 3 |
Rated Capacity | 3 x 10590 kVA |
Power Factor | 0.85 |
Voltage | 11 kV |
Frequency | 50 Hz |
Excitation system | Brushless/ static |
Transformer | |
Rated capacity | Bank of 3 x 10.67 MVA, 11/132/√3, single phase |
Voltage ratio | 11 kV/ 132 kV |
Transmission Line | |
Voltage level | 132 kV Single Circuit |
Length | 1.2 km |
Power Generation | |
Installed capacity | 27 MW |
Net annual energy after transmission & outage losses | 142.75 GWh |
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