Electric power is the most vital input for industry and agriculture.
With the rising trend of oil prices and the need to conserve fossil
fuel resources for future use, exploitation of hydro electric
energy, which is a renewable and pollution free source of energy,
has become increasingly important. Developed countries have all
along given top priority to harnessing hydro power. In India, only
15 percent of potential for hydropower has been harnessed so far.
The Western Region of
the country in particular has been facing shortage of peaking power.
Actual shortage at the end of 8th Plan was assessed to be 3360 MW.
The power generation in this region is predominantly thermal based
and hence there is an urgent need to develop the hydroelectric
resources to meet the peak load requirements.
Project with its installed capacity of 1450 MW was initially
envisaged to start yielding benefits during the 8th five-year Plan.
But this could not be realised, because of slippage in the
construction of the project.
SARDAR SAROVAR MULTIPURPOSE PROJECT
The Sardar Sarovar multipurpose project in Gujarat is terminal dam on river Narmada being implemented by Sardar Sarovar Narmada Nigam Limited (SSNNL), Gujarat and comprises :
- A 1210 m long and 163 m high (from deepest foundation) high concrete gravity dam across river Narmada near village Navagam with live storage 5800 Mcum (4.72 Maft) between FRL + 138.68 m (+455 ft) and MDDL 110.64 m (363 ft).
- A 458 Km long lined canal taking off from the right flank of the reservoir with FSL + 91.44 m (+300 ft) at head and up to Rajasthan State border. The canal extends another 74 Km in Rajasthan beyond Gujarat/Rajasthan border. The capacity at head being 1132.7 cumecs (40000 cusecs) which will taper down to 70.8 cumecs (2500.00 cusecs) at the Gujarat – Rajasthan border. The Canal shall irrigate areas in Rajasthan as well as in Gujarat.
- A Canal Head Power House (CHPH) on the right flank near Sardar Sarovar dam having five Kaplan type units of 50 MW each operating under a head varying from minimum of 18.12 M to maximum of 46.13 M and utilizing waters to the extent of requirements of Gujarat & Rajasthan but limited to their share.
- A River Bed Power House (RBPH) located underground in the right abutment having six Francis type reversible pump turbine units of 200 MW each designed to operate under head varying from minimum of 75 M to maximum of 114 M by utilizing the surplus waters available at Sardar Sarovar reservoir.
- A tail pool dam located at Garudeshwar about 12.0 Km downstream of the Sardar Sarovar dam with a live storage capacity of 32.9 Mcum is envisaged for pumped storage operation of RBPH.
- Six circuits ( 2 nos. for each beneficiary States) of 400 kV transmission lines for evacuating SSP power and for sharing the benefits among M.P., Maharashtra & Gujarat.
The power generation in the Sardar Sarovar Power complex would depend on the irrigation development upstream in M.P. as well as development in Gujarat/Rajasthan under Sardar Sarovar Project. As the power generation at RBPH is dependent on the water availability surplus to irrigation utilization/share of the party States, therefore, it would progressively reduce as irrigation develops in the basin. Thus, the RBPH would lose both capacity value and energy value in the ultimate stage of basin development and during dry years even in earlier stages. Pump turbines units are installed at RBPH to preserve the capacity value of the station and its continued utility as a peaking station throughout its life. The Narmada Main Canal has 4 ponds immediately downstream of the CHPH tail race to even out the fluctuations at the CHPHdue to peaking operation. Thus, the CHPH is planned to be operated as a peaking scheme.
The tail pool dam would comprise broad crested weir with sluices provided in the body of the dam. The pondage requirement of tail pool dam is assessed to be 27850 Acft considering 6 hours peaking operation.. It was also considered that the need for tail pool dam may also arise at correspondingly later date in case slow development of irrigation. Therefore the expenditure on tail pool dam is to be limited to the essential works needed to be carried along, with Sardar Sarovar dam to enable its construction at a later date as needed.
In order to enable the party States of Madhya Pradesh and Maharashtra to avail of their entitlement of their power, the NWDT in their final report provided for construction of the transmission lines in Gujarat up to its border with Madhya Pradesh and Maharashtra along an alignment agreed to between the parties. The transmission lines beyond Gujarat State border are to be constructed by Madhya Pradesh and Maharashtra in their respective States and to be included under their transmission and distribution expansion programme.
PROVISIONS IN NWDT AWARD ON POWER COMPONENT:
The provisions in the NWDT Award regarding power component are outlined below :-
- The power generated in the River Bed and Canal Head Power Houses (RBPH & CHPH) at Navgam will be integrated in common switchyard.
- Madhya Pradesh and Maharashtra are entitled to get 57% and 27% of the power available at bus bar in the switchyard after allowing for station auxiliaries.
- The above entitlement applies both to the availability of machine capacity for peak loads and to a total energy produced in any day.
- The entitlement of power and energy for any day can be utilized fully or partly by the concerned States or sold to another party States under mutual agreement. It cannot, however, be carried forward except under a separate agreement or working arrangement entered into among the affected parties.
- Gujarat will construct and maintain the transmission lines needed to supply the allotted quantum of power to Madhya Pradesh and Maharashtra up to Gujarat State border along an alignment as agreed to between the parties and if there is no agreement along such alignment as may be decided by NCA. The transmission lines beyond Gujarat State border shall be constructed and maintained by Madhya Pradesh and Maharashtra in their respective States.
- The power houses and appurtenant works including the machinery and all installations as well as the transmission lines in Gujarat State will be constructed maintained and operated by Gujarat State or an authority nominated by the State.
- The Authority in control of the power houses shall follow the directions of the NCA in so far as use of water is concerned.
- The scheme of operation of the power houses including the power required and the load to be catered for to the different party States during different parts of the day shall be settled between the States at least one week before the commencement of every month and shall not be altered during the month except under agreement among the States or under emergencies.
POWER SUB-COMMITTEE OF NCA
With a view to facilitate compliance to implementation of directions of NWDT pertaining to power component Hydro Power (Unit III) of SSP complex as outlined in para 3.0. NCA in its 11th meeting held on 15/06/1983 set up a Power Sub-Committee (PSC) under the Chairmanship of Member (Power), NCA with representatives from the beneficiary States, Central Electricity Authority (CEA) and Western Regional Power Committee (WRPC) and concerned State Electricity Boards/Corporations.
The terms of reference of Power Sub-Committee are as under :-
- Monitoring of power & energy generation/ transmission of Sardar Sarovar Project (SSP) complex and ensuring the sharing between the beneficiary States
- Alignment of transmission lines for evacuation of power from SSP power stations to the beneficiary States.
Keeping in view the role assigned to NCA as enumerated above and in the present scenario viz. completion of transmission lines and commencement of power generation , the Power Sub Committee during its 38th meeting held on 03/02/2006 proposed to review the terms of reference as under :-
- Monitoring of power & energy generation/ transmission of Sardar Sarovar Project (SSP) complex and ensuring the sharing between the beneficiary States.
- Matters related to O&M of Sardar Sarovar Project (SSP) complex and optimization of power generation etc.
- To review the safety aspects of SSP complex.