Project Details

Project Name

: Naugarh Gad Hydroelectric Project

Development Region

: Far Western

Zone

: Mahakali

District

: Darchula

Intake Site

: Dhuligada VDC

Powerhouse Site

: Dethala VDC

Geographical Co-ordinates

Latitude

: 29°43'30" N to 29°41'15" N

Longitude

: 80°36'46" E to 80°36'15" E

General

Water Source

: Naugarh Gad

Nearest Town

: Gokuleshwor

Type of Scheme

: Run-of-river

Gross Head

: 137.0 m

Net Head

: 122.30 m

Installed Capacity

: 8,500 kW

Hydrology

Catchment Area

: 194 km²

Average Annual Precipitation

: 2192 mm/year

100 years Design Flood (HW)

: 323 m³/s

100 years Design Flood (PH)

: 753 m³/s

Minimum Monthly Flow

: 3.58 m³/s

Riparian Release Intake

Naugarh Gad

: 0.358 m³/s

Headworks

Diversion Structure

: Hard Stone Lined Gravity Free Flow Weir

Type of Weir

: Concrete gravity dam

Length of Weir

: 37.05 m

Weir Crest Elevation

: EL 870 msl

Height of Weir

: 3.50 m from U/s Apron

Undersluice

: 2 Vertical Sluice Gates

Crest of Sluice

: EL 866.70 msl

Size of Sluice Gate (b x h)

: 3.0 m x 2.6 m

Intake Type

: Side Intake

Size of Opening

: 2.50 x 1.40 – 4 nos

Crest Elevation of Intake

: EL 868.80 msl

Gravel Trap

Type

: Rectangular with Slide Slopes

No. of bays

: 2

Particle Size to be Settled

: 20 mm

Trap Efficiency

: 98 %

Size of Gravel Trap (LxBxH)

: 14.50 m x 7.50  x (2.85 m – 3.95 m)

Spilway Length

: 17.06 m

Bed Slope

: 1:10

Flushing Channel Size

: 2 Nos. of 1.2 m x 1.0 m Rectangular Closed

Desander

Type

: Double Dufour Double Chamber Continuos Flushing Type

Trap Efficiency

: 90%

Size of Each Chamber (LxBxH)

: 55.0 m x 7.50 m x (3.65m – 4.65m)

Bed Slope

: 1:50

FSL @ Desander end

: 869.80 msl

Flushing Channel Size

: 2 Nos. of 1.0 m Rectangular

Headrace Pipe

Type

: MS-Pipe beried Section

Total Length

: 3740.40 m

Pipe Material

: IS 2062-B

Thickness

: 8 mm to 16 mm

Diameter of Pipe

: 2.10 & 2.0, 10mm – 12mm Thickness

Surge Tank

Type

: Circular Cylinder, Concrete (RCC)

Number of Chamber

: 1

Dia of Tank

: 12.0m

Total Height of Tank

: 24.30 m

Invert Level of Tank

: 854.15 m

Static Level

: 870.00 m

Upper Surge Level

: 878.16 m

Down Surge Level

: 855.87 masl

Penstock Pipe

Type

: MS-Pipe Open Structure

Length

: 14m from T  to Surgetank and 633.8m from T to Powerhouse

Pipe Materialize

: IS 2062-B

Size of Pipe

:1.7m dia , 10mm thick (from T-ST) & 1.9m dia 12mm-22m (from T-PH)

Number of Anchor Blocks

: 13 Nos. Including T, Y, B and A

Number of Supports

: 80 Nos.

Powerhouse

Type

: Surface

PH Dimensions, main Building (l x b)

: 29.80 m x 9.50 m

Height of PH Building

: 9.50 from Plinth Level

PH Floor Level

: EL 732.50 m

Tailrace

Type

: Closed Rectangular RCC Canal

Length

: 146.60 m (Including Both Units)

Size (w x h)

: 3.0 m x 2.75 m

Tailrace Water Level

: El 733.0 m at Outlet

Slope

: 1:500

Turbine

Type of Turbine

: Francis

Number

: Two (2)

Shaft Arrangement

: Horizontal

Rated Discharge for each Turbine

: 4.15 m3/s

Rated head

: 122.30 m

Rated Output for each Unit

: 4500 kW

RPM

: 1000

Rated Efficiency

: 90 % (at 100% Discharge)

Generator

Type

: Synchronous brushless, 3Ø AC

No of Units

: 2

Rated Voltage

: 6.3 kVA

Power Factor

: 0.85

Layout

: Horizontal

Rated Efficiency

: 96%

Rated Output

: 5000 kVA

Rated Frequency

: 50 Hz.

Power Transformer

Type

: Step up Power Transformer

Rated Capacity

: 11000 kVA

Rated Efficiency

: 99%

No of Unit

: 1

Number of Phases

: 3 ph, 50 Hz

Types of Connection

: Star/Delta

Type of Cooling

: ONAN

Voltage Ratio

: 6.3 kV (LV Side) / 132 kV (HV Side)

Station Supply Transformer

Type

: Indoor and Outdoor Type

Rate Power Output

: 200 kVA

No of Unit

: 2

Type of Cooling

: ONAN

Voltage Ratio

: 6.3/0.4 kV

Connection / Vector Group

: Dyn11

Transmission & Interconnection

Power House – Balanch Substation

: 4.8 km

Type of Circuit

: 33 kV Single Circuit Line up to 132 kV Balanch S/S

Line Conductor

: ACSR "DOG" 150mm²

Transmission Voltage

: 33 kV

Proposed Interconnection Point

: Balanch 33/132 kV Substation

Power and Energy

Installed Capacity

: 8.50 MW

Total Gross Energy

: 53.64 GWh

Contract Energy after Outage & Loss

: 50.96 GWh

Wet Saleable Energy

: 40.40 GWh (79.27%)

Dry Saleable Energy

: 10.56 GWh (20.73%)

Project Financial Indicators

Base Cost of the Project

: 1339 Millions NRs(Without IDC)

Term Loan

: 98 Crores

Interest Rate

: 8.5%

PPA Rate

: 4.00 Wet and 7.00 Dry Season  

Simple Payback Period

: 6.3 years

B/C Ratio

: 1.26

IRR

: 15.38%

EIRR

: 20.65%

Average DCBR

: 1.17