Project
Dar Khola Hydropower Pvt. Ltd. is developing Run-of-River (ROR) type Dar Khola Hydropower Project 6.5 MW in Dar Khola of Dhaulagiri Rural Municipality, Myagdi District.
Darkhola Hydropower project has connection to the motorable road. Beni lies about 300 Km west of Kathmandu. From Beni to Dara is around 42KM, Dara Gaun which is the site for Dar Khola Hydropower Project.
Dar Khola is one of the tributaries of Myagdi River, which is one of the major tributaries of Kali Gandaki river. Dar Khola is located in Myagdi District, Dhaulagiri zone, Gandaki Province of Nepal. Project has a catchment of 62.70 km2. Geographically the project lies between latitudes 28° 30′ 00″ North and 28° 30′ 40″ North and longitudes 83° 18′ 47″ East and 83° 20’20” East in Myagdi District. Project has a gross head of 548.0 m and design discharge of 1.44 m3/s in probability of exceedance (Q 44.5%).
The source of water for Dar Khola Hydropower Project is originated from Dar Khola which is a perennial rain fed river starting at an elevation of 4066m from the High Mountain/Hilly areas. The proposed intake site at Dar Khola lies at an elevation of about 1867 m, whereas the proposed powerhouse site lies at right bank of Myagdi Khola just downstream from the confluence of Dar Khola with Myagdi Khola. As per Physiographical Region, 6.62% and 93.38% of the catchment at intake site of Dar Khola lay in High Himalayan and High Mountain Region respectively. More than one third of the catchment is covered by fairly dense mixed forest. The total catchment area contributing flow at intake site and at powerhouse site are 62.70 Km2 and 71.40 Km2 respectively.
Salient feature of Project
| Project Location | ||
| Province | : | Gandaki |
| District | : | Myagdi |
| Intake Site | : | Kunauta Muna, Dhaulagiri Rural Municipality Ward No. 3 |
| Powerhouse Site | : | Near confluence of Dar Khola and Myagdi Khola at Solbang Dobilna Phaliagaun of Dhaulagiri Rural Municipality Ward No. 3 |
| Geographical Co-ordinates | ||
| Latitude | : | 28° 30′ 00″ N and 28° 30′ 40″ N |
| Longitude | : | 83° 18′ 47″ E and 83° 20′ 20” E |
| General | ||
| Name of River | : | Dar Khola |
| Nearest Town | : | Beni |
| Type of Scheme | : | RoR |
| Gross Head | : | 558.00 m |
| Net rated Head | : | 530.08 m |
| Installed Capacity | : | 6.50 MW |
| Average Annual Energy after Outage | : | 36.29 GWh as per PPA |
| Hydrology | ||
| Catchment Area | : | 62.70 km2 |
| Mean Annual Discharge | : | 2.94 m³/s |
| Design Discharge (at 42.42% PoE) | : | 1.44 m³/s |
| Riparian Release | : | 0.039 m³/s |
| Design Flood Discharge | : | 104.94 m³/s at headworks |
| Average Annual Precipitation | : | 2334.22 mm |
| Diversion Weir | ||
| Type of Weir | : | Broad Crested Weir |
| Width of Weir | : | 10 m |
| Crest Elevation | : | 1861.50 masl |
| Undersluice Opening (W X H) | : | 2.0 X 2.2 m |
| Undersluice Crest Level | : | 1857.77 masl |
| Intake | ||
| Type of Intake | : | Side |
| Nos of Opening | : | 3 nos. |
| Size of Intake (W x H) | : | 1.8 x 0.6 m |
| Intake Sill Level | : | 1860.20 masl |
| Gravel Trap | ||
| Size (L x B x H) | : | 6.00 m x 4.90 m x 4.10 m |
| Normal Operation Level | : | 1861.38 masl |
| Particle size to be trapped | : | 4 mm |
| Gravel Flushing Channel | : | 0.60 m x 0.60 m |
| Desander | ||
| Type | : | Hopper Type, Intermittent Flushing |
| Size (L x B x H) | : | 30.00 m x 3.80 m x 3.49 m, 2 nos. |
| Inlet Transition Length | : | 4.25 m |
| Particle Size to be settled | : | 0.15 mm |
| Trapping Efficiency | : | 90% |
| Headpond | ||
| Type | : | Open Channel |
| Size (L x B x H) | : | 6.16 m x 4.50 m x 2.53 m |
| Normal Operation Level | : | 1861.34 masl |
| Headrace Pipe | ||
| Type | : | Steel Pipe with partially buried & partially exposed |
| Total Length | : | 3191.95 m |
| Internal Diameter Length | : | 1.0 m, 0.9 m & 0.8 m 1555.62 m, 1459.39 m & 176.64 m |
| Steel Grade | : | E250 as per IS 2062:2011 |
| Steel Thickness | : | 8 mm |
| Nos. of Anchor Blocks | : | 75 |
| Nos. of Saddle Pad | : | 114 |
| Nos. of Saddle Supports | : | 178 |
| Surge Tank | ||
| Type | : | Steel Pipe lying on the ground |
| Diameter | : | 1.50 m |
| Length | : | 275.38 m |
| Steel Grade | : | E250 as per IS 2062:2011 |
| Steel Thickness | : | 12 mm |
| Maximum Upsurge Level | : | 1879.80 masl |
| Minimum Downsurge Level | : | 1834.59 masl |
| Penstock Pipe | ||
| Type | : | Steel Pipe with partially buried & partially exposed |
| Internal Diameter | : | 0.80 m |
| Length | : | 1276.72 m |
| Steel Thickness | : | 8 – 20 mm |
| Nos. of Anchor Blocks | : | 16 |
| Nos. of Saddle Pad | : | 24 |
| Nos. of Saddle Supports | : | 173 |
| Powerhouse | ||
| Type | : | Surface |
| Size (L x B x H) | : | 22.00 m x 9.00 m x 10.84 m |
| Turbine Axis Level | : | 1303.50 masl |
| Tailrace | ||
| Type | : | Open Channel |
| Tailrace Length | : | 38.40 m |
| Size (W x D) | : | 0.70 x 1.00 m |
| Tailrace Water Level | : | 1300.60 masl |
| Turbine | ||
| Type | : | Pelton, Horizontal Axis |
| Number | : | 2 nos. |
| Rated Output Capacity per unit | : | 3.25 MW |
| Turbine Axis Level | : | 1303.50 masl |
| Net Head | : | 530.08 m |
| Discharge per unit | : | 0.72 m3/s |
| Efficiency | : | 90% |
| Governor | ||
| Type | : | Electro-hydraulic |
| Sensitivity | : | 0.01% |
| Accuracy | : | 95-100% |
| Generator | ||
| Type | : | Salient pole, synchronous |
| Capacity | : | 3823 KVA (2 Nos) |
| Power Factor | : | 0.85 |
| Generator Voltage | : | 11 kV |
| Frequency | : | 50Hz |
| Excitation System Type | : | Brushless |
| Efficiency | : | ≥ 96% |
| Synchronous Speed | : | 750 rpm |
| Transformer | ||
| Number of Transformers | : | Two (2), Three Phase |
| Type | : | Outdoor, oil immersed |
| Vector Group reference | : | YNd11 |
| Efficiency | : | ≥ 99 % |
| Transmission Line | ||
| Voltage Level | : | 33 kV |
| Length | : | 7 km |
| Conductor Type | : | ACSR Wolf Conductor |
| Evacuated to | : | Dandakhet Substation |