SUPPLEMENTING PLANT EFFORTS

SOLUTION OF CHRONIC PROBLEMS

Development of Hydro suction

Used Hydro suction Sedimentation Exclusion System from dam for the first time in India at Salal Power Station, which has given encouraging results. This arrangement has also been used successfully in Tanakpur Power Channel. .

PREVENTIVE MEASURES AGAINST SILT EROSION OF UNDER WATER COMPONENTS

SILT MENANCE Underwater parts of Hydroelectric Power Stations located in Himalayan region in general and run-of-the river schemes located in the Northern states of India in particular suffer from silt erosion.   Particularly in Monsoon days when 98% of the silt particles of size 0.25mm and smaller are of quartz with hardness of 7-8 on Moh's scale pass through turbine.  It is not cost-effective to construct de-silting arrangement to remove this size of silt from flowing water. The operation and maintenance of these power stations is indeed a tremendous task and calls for high degree of dedication and motivation on the part of maintenance staff in grappling with the silt related problems.

FIELD TRIALS   Salal & Baira Siul Power Stations of NHPC have been the worst victims of Silt erosion. Field trials with thermal spray coatings, polymeric coatings & plasma nitrding have been carried out at these power stations, out of which HVOF process WC-Co coating gave some success to retard erosion.   EXISTING STATUS   In the year 2005, NHPC management has taken a decision to drop these field trials at project sites on the account of following: o        Field trials in isolation of active involvement of OEM’s is not likely to be fruitful, as the technology is to be adopted by OEM’s.  NHPC will consider to participate in field trials, if proposed by OEM’s. NHPC is taking up the issue with OEM’s for a joint collaboration for finding solution to mitigate silt erosion.

NATIONAL PERSPECTIVE PLAN ON R&D IN THE POWER SECTOR    ·         Standing Committee of Govt. of India on R&D approved the proposal on National R&D Project for Development of Silt Resistant Material for elongation of service life of underwater components for which National Metallurgical Laboratory, Jamshedpur(NML) is the lead agency and NHPC is one of the participating agency. The completion schedule of this project is 3 years and the cost of project is Rs.299.79 Lakhs. MOU for signing between the participating agencies is under finalization.

SKILL DEVELOPMENT OF PERSONNEL

Training & Certification of Welders

·         A sharp vigilance to the quality of welds produced at the Projects/ Power stations reveals the fact that it is imperative to train our welders to international standards to obtain quality weld especially in rebuilding and refurbishing of underwater components.  ·         Subsequently the matter was taken up with the firms viz. WRI, Tiruchirappalli, L&T etc. to explore the best appropriate training to be provided to our welders to improve their efficacy. As a result with the association of HRD Division more than four dozen of welders are already trained as per ASME Sec-IX at WRI. ·         Further training, including refresher & advanced training are in the pipeline.

OTHERS

Adoption of Energy Efficient Technology

·        Fitch Fuel Catalyst is a pre-combustion, emission reducing and a fuel economy improvement technology comprising of a heterogeneous metal alloy that is installed in the fuel line system of any gasoline, diesel or propane powered equipment. ·         It is stated to improve engine power, reduce harmful emissions, reduce   maintenance & operating costs. ·        NHPC has conducted field trails at Chamera-I, Chamera-II, Rangit and Dhauliganga Hydroenectric Projects and initial results were found encouraging. ·         Based on the encouraging results of the field trials, NHPC power stations were encouraged to use the catalyst on vehicles/equipments depending upon their usage (working hours) requirement taking into account the return on investment (ROI).

OPTIMIZING USE OF ENERGY & PERFORMANCE

Energy Audit

‘Energy audit ” means the verification, monitoring and analysis of use of energy including submission of technical report containing recommendations for improving energy efficiency with cost benefit analysis and an action plan to reduce energy consumption. As per the Energy Conservation Act, 2001 , Bureau of Energy Efficiency(BEE) has identified Energy Intensive Industries as designated consumers. Central Govt. may direct, any designated consumer to get Energy Audit conducted by an accredited Energy Auditor. Without any such directive from Central Govt., NHPC voluntarily taken up the Energy Audit of its Power Stations. Energy audit of Baira Siul & Salal Power Stations has been completed in March’ 05 & September’05 respectively. Energy Audit of Tanakpur and Loktak Power Stations has been completed during 2006-07.  Energy Audit of Rangit & Chamera-I Power Stations is to be completed during 2007-08. Energy Audit results in cost savings as well as reestablishing the validating of actual performance vis-a-vis design parameter.

NEW INITIATIVES

CDM (CLEAN DEVELOPMENT MECHANISM)

·         The Clean Development Mechanism (CDM), is one of the three flexibility mechanisms under the Kyoto Protocol (KP), 1997 that enables developing countries to assist developed countries in meeting their green house gas (GHG) emissions reduction targets. Of proposed GHG abatement projects, those involving renewable energy (RE) are the most promising because they generate clean energy and promote sustainable development. ·         Project Idea Notes (PINs) for 15 (Fifteen) project have been prepared. ·         The work of development of Nimoo-Bazgo and Chutak Hydroelectric Projects as CDM Projects has been awarded to M/s MGM International & IDBI Bank. ·         Host Country approval for Nim00-Bazgo and Chutak Projects have been obtained from National CDM Authority in August 2007 ·        Validation of Nimoo-Bazgo and Chutak Projects by Designated Operational Entity (DOE) shall be undertaken after signing of agreement. ·        Signing of Agreement between M/s MGM International & IDBI and NHPC for these two projects is under process. ·         Data Collection & Feasibility Studies on other projects for consideratio of CDM benefits are in process.

COMPUTATIONAL FLUID DYNAMICS SOFTWARE LAB

·         CFD is extensively applied in the design of components in the water path like spiral casing, stay vanes, guide vanes, runner blades and draft tube. Accurate prediction of losses and design analysis aid in optimization of the performance of the hydro turbines. Various design parameters of the under water components are simulated by the use of CFD. ·         Following applications can also be considered for CFD studies. -                      3-D sediment movement along the reservoir. -                      3- D reservoir flushing. -                      Modeling sediment movement in the vicinity of the intake for the given sediment profile and flow condition. -                      Hydraulic transients – water hammer and mass oscillations for complete water conductor system. -                      Hydraulics around surge tank orifice. -                      Hydraulics in TRT outlet area. -                      Optimization of size, shape and length of de-silting basin and flushing arrangement. ·         For this purpose, a good knowledge of two-phase computational fluid dynamics, as well as efficient interactive visualization software, is required. ·         Technical specifications of the software and hardware have been finalized in co-ordination with IT Division.

ECOLOGICAL STUDY OF HYDRO RESERVOIR

·         Ecological Study of hydro reservoir has been taken up to assess the role of reservoir in GHG emission and its contribution to climate change. ·         Phase-I Ecological study of Teesta river at Teesta Stage-V Hydroelectric Project has been got done by National Environmental Engineering Research Institute (NEERI), Nagpur. ·         Phase-II ecological study is under process.

CO-OPERATION WITH IRTCES, CHINA

·         An MOU between IRTCES, China and NHPC has been signed on Nov, 2006 for co-operation on various research areas. ·         Specific research areas relevant to NHPC needs have been identified and Interaction for separate agreements for different areas of research with IRTCES, China is under process. ·        For Joint cooperation research on management high sedimentation content in short reservoir, two projects namely Rangit & Dhauliganga Projects from NHPC and two projects namely  Gaunting reservoir in Yongding river and Hongshan reservoir in Liaohe river  from IRTCES, China have been selected. ·        Representative from IRTCES, China will be visiting NHPC from 18 -25th September 2007 for detailed discussion on joint cooperation research on management of high sedimentation content in short reservoir.

PRELIMINARY STUDY OF DOWNSTREAM RELEASE OF WATER OF HYDRO POWER PROJECTS

·         Preliminary study of down stream release of water of hydro power projects has been taken up as a research project. ·         To formulate the exact scope of this study information/data (Environmental, Technical, Commercial, Legal and other data) pertaining to down stream release of water from dam has been collected from projects, related functional group. ·         Data from other organisations( National / International)  are being collected. ·         National & International norms/guidelines on the subject matter are being searched for in-depth study on the matter.