Sinafdar Pumped Storage Scheme (3 x 115 MW)

 

 Introduction

To cater the power requirement of state, Bihar State Hydroelectric Power Corporation Ltd., (BHPC) is trying to exploit the available hydro potential in the state. In the process of identifying the potential sites for hydro power generation, reconnaissance survey was got conducted by BHPC through NHPC to set up large hydel projects in the district of Kaimur and Munger in Bihar. Reconnaissance survey report was submitted by NHPC to BHPC in May 2002. NHPC in it report identified some hydel projects for possible development. It was also found that from geological and topographical considerations, it was possible to develop Pumped Storage scheme at some locations subject to technical feasibility and economical viability.            

Project Purpose

 Sinafdar fall site is located on the Karsotha Nallah in the Kaimur district of Bihar. The site is located about 60 km from Bhabua road which is the nearest rail head. The site is suitable for a Pumped Storage scheme. The power required for pumping the water from lower reservoir to upper reservoir shall be taken from the grid during off-peak hours when it is available at cheaper rates.  This will act as value addition to nearby thermal power plant and improve the grid stability. Pumped Storage Schemes consume energy during off-peak hours thereby improving plant load factor of thermal plants. These can act as spinning reserve and help in improvement of load factor of the system. Pumped Storage Schemes can provide the required peaking support especially during lean season. It also helps in smoothening the frequency curve. Pumped Storage Schemes are independent of vagaries of monsoon. During peak period the Sinafdar Pumped Storage Scheme shall provide the required high value power to the State of Bihar.

 Salient Feature

 

1.0

Location 

 

Country

India

 

State

Bihar

 

District

Kaimur

 

River

Sura river (Right fork)

 

Project Area  

 

Longitudinal (Upper dam Site)

E 830 36’ 47”

 

Latitude

N 240 49’ 51”

 

Access to the Project

Bhabua town  45 km

 

Nearest village

Salea-Dahar

 

Airport

Patna (240km) / Varanasi(130KM)

 

Nearest Railhead

Bhabua road 60 km

 

Port

Kolkata

2.0

Scheme

 

 

Type

Pumped Storage

 

Installed Capacity

345 MW

3.0

Hydrology

 

 

Catchment area  

 

Upper dam

27.96 sq.km

 

Lower dam

13.73 sq.km

 

Maximum annual rainfall

1300 mm.

 

Minimum annual rainfall

540 mm

 

Max. Intensity (One day) at Bhagwanpur

131 mm/day

 

Maximum observed flow at Sinafdar fall

6.113 cumec

 

Minimum observed flow at Sinafdar fall

0.000 Cumec

 

Maximum Design Flood  

 

Upper dam

140 Cumec

 

Lower dam

80 Cumec

 

Annual average sediment load

0.07 Ha M/ Sq km / year

(at Kadhwan)

 

Annual Average evaporation

145 cm (Average of Kadhwan, Purulia and Koel Karo)

4.0

Civil Structure

 

4.1

Upper Dam

 

 

Type

Rockfill with central clay core

 

River bed level

El. 280 M

 

Top level of the Dam

El. 325 M

 

Maximum height (Above riverbed level)

45 m

 

Top width of the Dam

8m

 

Length of the Dam  at top

500 m

 

Diversion Structure  

 

Type

Tunnel

 

Length

100 m

 

Diameter

4m

 

Spillway  

 

Type

Tunnel

 

Length

450 m

 

Diameter of tunnel

4m

 

Crest Level

El. 282 M

 

Design flood

140 Cumec

 

Type of gate

Vertical lift

 

Reservoir  

 

MDDL

EL 300 M

 

FRL

EL 320 M

 

Gross capacity

9.88 Mcum.

 

Live storage

8.08 Mcum.

 

Reservoir surface area at FRL

65 ha.

4.2

Lower Dam

 

 

Type

Concrete/RCC dam

 

River bed level

El 148 M

 

FRL

EL 185 M

 

MDDL

EL 170 M

 

Top level of Dam

EL 190 M

 

Maximum height

42 m

 

Top width of Dam

8m

 

Length of the Dam at the top

160 m

 

Spillway  

 

Type

Under sluice

 

No. of bays

2

 

Size of bays

2m x 4m

 

Crest level

EL 153 M

 

Design flood

80 Cumec

 

Type of gate

Radial gate

 

Reservoir   

 

MDDL

EL 170 M

 

FRL

EL 185 M

 

Gross capacity

12.38 Mcum.

 

Live Storage

7.88 Mcum.

 

Reservoir surface area at FRL

58 ha.

4.3

Upper Intake/outlet

 

 

Type

Isolated

 

No. of Intakes

3

 

Discharge (With 10% overload load

135 Cumec

 

Gate

Vertical Lift type

 

Invert level of intake

El. 285 M

4.4

Head race tunnel

 

 

Type

Partly steel & partly concrete lined

 

Shape

Horse-shoe

 

Number

3

 

Diameter

7m

 

Length

Steel lined 65 m Concrete lined   500 m

4.5

Pressure Shaft

 

 

Type

Party steel & partly concrete lined

 

Shape

Circular

 

Number

3

 

Concrete Lined  

 

Length

194 m

 

Diameter

7m

 

Steel Lined  

 

Length

100 m

 

Diameter

6m

4.6

Surge Shaft

 

 

Number

3

 

Shape

Circular

 

Height

60 M

 

Diameter

14 m

4.7

Power House Complex

 

 

Type

Under Ground

 

Size of Power House Cavern

107x21x40m

 

Service bay level

EL 170 M

 

C.L. of Machines

EL 160 M

 

Installed capacity

3 x 115 MW

 

Peak operating duration

6 hours

4.8

Transformer Cavern cum gate shaft

 

 

Type

Under Ground

 

Size

100x15x28m

 

Service bay level

EL 187 M

 

Cable shaft

 

 

Diameter

6 m

 

Height

30 m

4.9

Tailrace outlet / lower intake

 

 

Type

D-Shaped tunnels

 

No. of tunnels

3 Nos.

 

Diameter

7 m

 

Tunnel length

175 m

4.10

Switchyard

 

 

Type

Surface

 

Dimension

200 x 100 m

 

Elevation

El. + 280 M

5.0

Estimated cost

 

 

Total project Cost

(excluding transmission line)

Rs. 1184.74 Crores at Jan 2006 price level

 5.3

Annual  Energy Generation, Off peak Energy for pumping and tariff

 

(a)

6 hours peaking and 8.6 hours pumping
i) Energy Generation 753.48 MU
ii) Pumping energy 1087.16 MU
iii) Sale rate at bus bar Rs. 4.95 without free power
iv) Sale rate at bus bar Rs. 5.63 with 12% free power

(b)

4.6 hours peaking and 6 hours pumping
i) Energy Generation 565.11 MU
ii) Pumping energy 807.3 MU
iii) Sale rate at bus bar Rs. 5.98 without free power
iv) Sale rate at bus bar Rs. 6.79 with 12% free power

(c)

4 hours peaking and 5.75 hours pumping
i) Energy generation 502.32 MU
ii) Pumping energy 726.57 MU
iii) Sale rate at bus bar Rs. 6.52 without free