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Background
Maneri Bhali Stage-II
Hydroelectric Project is a Run-of-River(ROR)
scheme under construction on river Bhagirathi, in
District Uttarkashi (Uttaranchal). The project, is
located near the famous city of Uttarkashi and is
on the downstream of the existing UJVNL's Tiloth
Hydro Power Project. The project site is
approximately 150 kms. from Rishikesh, lies
between the tailracechannel of Maneri Bhali Stage-I
project and the reservoir of Tehri project.
The project preliminary works were started
in 1979 by the erstwhile UPSEB along with UP
Irrigation Department and the main civil works
contracts were signed in the years from 1980-84.
The original estimate of the project (with an
installed capacity of 3x52 MW), costing Rs.
4333.00 Lakhs, was submitted to CWPC in April
1972. The cost was updated to Rs. 4571.00 Lakhs during
examination by CWPC
in June, 1973. This cost was cleared by CWPC. The
project installed capacity was then revised to
4x76 MW due to revision in design discharge of HRT
from 120 cumecs to 142 cumecs.The civil
works on the project at Diversion dam and tunnel
were taken up but the pace was slow due paucity of
funds and geological hurdles. The works finally
came to a halt in 1990-91 due to non availability
of funds. By then 9 km of tunnel had been
excavated and works of barrage complex were in
advance stage of completion. The orders for the
Generating equipment of the power stations had
also been placed with M/s B.H.E.L. and an expenditure of Rs.153
crores had been made on the project. Subsequently,
Government of UP made efforts to get the project
completed in private sector or through Central
Sector undertakings viz. NHPC, THDC etc. but could
not succeed in making headway. The project
estimate was revised on 2/99 price base for Rs.
1249.18 crores (including escalation and IDC) and
techno-economic clearance was accorded by CEA vide
their letter number F.No. 2/UP/46/99-PFC/1298-1321
dated 21.2.2000.
Revival of the Project after formation of Uttaranchal
After the formation of Uttaranchal on 9.11. 2000 and Uttaranchal Jal Vidyut Nigam Ltd. (UJVNL)
on 9.11.2001, a decision was taken to revive the project to unlock the investments on the project (Rs 165 crores up to 10/2002) and derive benefit of power generation. Financial Assistance for the project was taken from Power Finance
Corporation(PFC). Now, on 1/2005 price base, a
revised estimate of Rs. 1714.41 crores have been submitted
to CEA, New Delhi for approval.
The restart of the project was a major challenge requiring financial intermediation, revival of old civil work contracts and detailed inspection of the half completed works which might have seen the aging effect and deterioration during the long idle period. The earlier civil work contracts were revived and considerable renovation work of infrastructure like roads, buildings and other facilities had also
been done.
The MOU between UJVNL and Irrigation Department was signed on 25.06.2002. and the major works were
started in October 2002. The project was slated for commissioning in
Octobet 2005.
Due to non-completion of the civil works, the
revised schedule of commissioning of project
is now March 2007.
Salient features of the project
1. 81 meter long barrage with a storage capacity of 7.55
lac cum., with intake and sedimentation tank near the
barrage. The barrage will provide a daily peaking of about four hours during the lean season
.
2. 16 km long, 6.0 m diameter horse shoe
shaped head race tunnel from Diversion barrage to power house with 172 m high, restricted orifice type surge tank, of 13.7 m diameter, at the end of the head race tunnel.
3. Four steel penstocks of 3.0 m diameter.
4. A surface power station of 4 units of 76 MW
(BHEL make) with Francis turbines along with a 220 kV switchyard.
5. Annual generation of 1566GWh.
The power from the project shall be evacuated to Rishikesh sub-station through three 220 kV lines. Two lines, which are already evacuating power to Rishikesh from Maneri Bhali Stage-I,
are to be looped in and out at this switchyard. The third line is being constructed by
Power Transmission Corporation of Uttaranchal Ltd.(PTCUL), wing of
Uttaranchal Power
Corporation. Foundation work of 156 out of 216
tower locations has been completed and 148 tower
have been erected. Case for the clearance of
forest land for 65 tower has been submitted in
M.O.E.F., whose team has visited the site, the clearance
is awaited.
Technology Assimilation
Efforts have been made to adopt the state of art technology during construction and operation and to provide best possible protection to the machines based on the past experience. Also to provide flexibility during operation and maintenance some features have been provided. Some of the major features are given below:
1. The governors and excitation system for the machines in the power station are microprocessor based and numeric relays are being provided in protection system.
2. Sedimentation chamber has been designed to exclude silt particles larger then 150 microns.
3. High Velocity Oxy Fuel (Tungsten Carbide) coating would be provided on under water parts of the machines to prevent erosion due to silt in river Bhagirathi containing very high percentage of quartz.
4. Facility to remove of runner from the bottom to facilitate faster replacement of runners and to avoid long outage of machines.
5. Single phase main transformers to reduce the transportation weight/ dimensions.
6. Nitrogen based fire protection system for transformers.
7. Unit penstocks with penstock protection valves to facilitate isolation of individual penstocks/ machines for maintenance and to avoid loss of generation.
8. Use of cyclonic strainers in cooling water system for machines to provide efficient filtration of water, good quality of cooling water and longer life to coolers.
Till 30/11/2006, 94.49% work of the project is
completed. All the E & M works will get
completed by the end of January 2007.
With the completion of project in March
2007, UJVNL would be able to generate
another 1,566 million units of energy (on
90% dependable discharge) in a year to the state of Uttaranchal. The project would also provide 4 hours of storage during lean season to provide high value peaking power.
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