Problems and prospects of setting up a thermal power plant (1)
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Problems and prospects of setting up a thermal power plant (1) Problems and prospects of setting up a thermal power plant (1) Document Transcript

  • UNIVERSITY OF PETROLEUM & ENERGY STUDIES, DEHRADUN Report on Problems and prospects of Setting up a Thermal power Plant Prepared for Dr. Neeraj Anand(Faculty for Project Management and Contract Administration) Prepared by Subhadip Manna
  • Table of contents1. Introduction ................................................................................................................................................. 12. Basics of Thermal Power Plant .................................................................................................................... 5 2.1 Classification of Thermal power plant ................................................................................................................6 2.2 Working of Thermal power plant ........................................................................................................................9 2.3Advantages of Thermal Power ...........................................................................................................................10 2.4 Disadvantages of Thermal Power .....................................................................................................................10 2.5 Efficiency: .........................................................................................................................................................11 2.6 Power Companies in India. ...............................................................................................................................133. Prospects of Setting up a Thermal Power Plant ........................................................................................ 15 3.1 LOCATION .......................................................................................................................................................16 3.2 WASTE MANAGEMENT ...................................................................................................................................17 3.3 Effluent and disposal .........................................................................................................................................18 3.4 Water Balance and Water Conservation in Thermal Power Stations ...............................................................194. Clearance Required Setting up a Thermal Power Plant ................................................................................ 20 4.1 Some basic Problems for Thermal Power plant Planning. .................................................................................215. Environmental checklist for Thermal Power Plant ....................................................................................... 22 5.1Tools for assessment and analysis .....................................................................................................................22 5.2 Guidelines of central electricity authority [CEA], government of India, ..........................................................23 for site selection of coal-based thermal power stations ..........................................................................................23 5.3 Guidelines for site selection of coal-based thermal power stations set by the MoEF .......................................246. EIA study report. ............................................................................................................................................ 24 6.1 Project Cycle .....................................................................................................................................................24 6.2 Project Analysis ................................................................................................................................................257. CONCLUSION ............................................................................................................................................... 278. REFERENCE ................................................................................................................................................. 28 i
  • 1. IntroductionPower generation is the harbinger of economic growth and industrial development of anycountry. Although it is a life stream of country like India, it contributes to the GHG emissions asthe fossil fuels have major share in total power generation. The section covers the current powersituation in India, development of renewable energy sources, central and state policies, futureenergy projections, current power delivery system etc.The electricity sector in India had an installed capacity of 210.951 GW as of December 2012, theworlds fifth largest. Captive power plants generate an additional 31.5 GW. Non RenewablePower Plants constitute 88.55% of the installed capacity and 11.45% of Renewable Capacity.India generated 855 BU (855 000 MU i.e. 855 TWh) electricity during 2011-12 fiscal.In terms of fuel, coal-fired plants account for 56% of Indias installed electricity capacity,compared to South Africas 92%; Chinas 77%; and Australias 76%. After coal, renewalhydropower accounts for 19%, renewable energy for 12% and natural gas for about 9%.In December 2011, over 300 million Indian citizens had no access to electricity. Over one thirdof Indias rural population lacked electricity, as did 6% of the urban population. Of those who didhave access to electricity in India, the supply was intermittent and unreliable. In 2010, blackoutsand power shedding interrupted irrigation and manufacturing across the country.The per capita average annual domestic electricity consumption in India in 2009 was 96 kWh inrural areas and 288 kWh in urban areas for those with access to electricity, in contrast to theworldwide per capita annual average of 2600 kWh and 6200 kWh in the European Union. Indiastotal domestic, agricultural and industrial per capita energy consumption estimate variesdepending on the source. Two sources place it between 400 to 700 kWh in 2008–2009. As ofJanuary 2012, one report found the per capita total consumption in India to be 778 kWh.India currently suffers from a major shortage of electricity generation capacity, even though it isthe worlds fourth largest energy consumer after United States, China and Russia. TheInternational Energy Agency estimates India needs an investment of at least $135 billion toprovide universal access of electricity to its population.The International Energy Agency estimates India will add between 600 GW to 1200 GW ofadditional new power generation capacity before 2050. This added new capacity is equivalent tothe 740 GW of total power generation capacity of European Union (EU-27) in 2005. Thetechnologies and fuel sources India adopts, as it adds this electricity generation capacity, maymake significant impact to global resource usage and environmental issues. 1
  • Indias electricity sector is amongst the worlds most active players in renewable energyutilization, especially wind energy. As of December 2011, India had an installed capacity ofabout 22.4 GW of renewal technologies-based electricity, exceeding the total installed electricitycapacity in Austria by all technologies.Indias network losses exceeded 32% in 2010 including non-technical losses, compared to worldaverage of less than 15%. Both technical and non-technical factors contribute to these losses, butquantifying their proportions is difficult. But the Government pegs the national T&D losses ataround 24% for the year 2011 & has set a target of reducing it to 17.1% by 2017 & to 14.1% by2022. Some experts estimate that technical losses are about 15% to 20%, A high proportion ofnon‐technical losses are caused by illegal tapping of lines, but faulty electric meters thatunderestimate actual consumption also contribute to reduced payment collection. A case study inKerala estimated that replacing faulty meters could reduce distribution losses from 34% to 29%.Key implementation challenges for Indias electricity sector include new project managementand execution, ensuring availability of fuel quantities and qualities, lack of initiative to developlarge coal and natural gas resources present in India, land acquisition, environmental clearancesat state and central government level, and training of skilled manpower to prevent talentshortages for operating latest technology plants.Despite the global slowdown, the Indian economy is expected to grow at 7.6 percent in thecurrent fiscal. In order to encourage a compassionate environment for economic development,equal contribution from all major sectors is required. Power sector is unanimously been acceptedas one of the vital inputs for economic growth. The overall growth of the Indian economy isdependent on the performance of power sector.The present level of energy consumption in India is quite low at 778 units per person whencompared to the global average of 2300 units per person. According to the Electric PowerSurvey, the energy requirement of India is expected to increase multifold from 9, 02,275 MUs in2011-12 to 37, 10,083 MUs in 2031-32. In order to meet this increasing requirement, thegovernment is planning for massive capacity additions in conjunction with bringing efficientchanges in the power verticals of transmission, distribution and trading.However, in the past few years, the pace and stage of development of power sector has beenslow in all the major segments. Due to several unattended issues wheeling the sector, capacityaddition target was revised from 78,700 MW to 62,374 MW. The final capacity addition furtherstands much lower than the revised target at 54,000 MW. 2
  • Major Reasons for SlippagesLack of fuel security. Shortage of coal Supply and unallocated gas is Private players overriding thehard hitting the operation of power plants. sector; 56% of capacity addition in 12th Plan to comeDelay in order placements for main plant in thermal projects. from private pool. The remainingfrom 26% centralDelay in order placements for civil works for thermal. and18% from state.Delay in order placement by BHEL.Delay in Land acquisition and environmental clearances. The government has scaled down its target of 75, 785 MW for the XII Plan from the previously planned 100000 MW. Of which, about 63, 781 MW is to come from Thermal sources, 9,204 MW from hydro and 2800 MW from Nuclear sources. In the XII Plan about 42,131 MW capacity additions is expected to come from the private sector alone. Coal demand-supply gap Gas demand supply gap is also set to continues to diverge and the diverge in the coming years. The gap between expected present gas demand only from power demand and indigenous sector is 61 mmscmd which is likely to The Twin availability is likely to reach translate into a demand of 207 Fuel Issues 137.03 MT by this plan mmscmd by the end of XII Plan. The which is to be met by total overall domestic availability of imports. The Gap is likely to gas is only 209 mmscmd and about widen to 200 MT by the end 150 mmscmd is expected to be of FY17. imported in the XII Plan. Coal shortage is likely to hit 46, 000 MW The government has asked the power power projects. producers to abstain from setting up new gas Costly imported fuel is eroding the profit based plants as the irregularity in gas supply margins of the producers. is threatening the viability of 37,000 MW of SEBs is unwilling to accommodate high- existing and upcoming projects. priced electricity. The government has also advised the Supply security from domestic sources developers not to plan domestic gas based yet not ensured. projects till 2015-16. 3
  • Initiatives for Coal Initiatives for GasIn order to secure the supply of coal in the country the government is The government needs to make looking forward to the captive coal amendments to its policies to attract blocks. Govt. has notified rules for more players in Exploration and allocation of coal blocks through Production activities. competitive bidding. About 50 coal blocks are to be allocated through The government is making arrangements this route. There is still lack of in sourcing gas from foreign countries like effective policy implementation in Canada. Besides, India is also setting eyes these terms and there is an urgent on Shale Gas from U.S. need to tie these, to yield Apart from sourcing gas from abroad, it is productive outcomes in terms of necessary to enlarge the domestic base coal production. for natural gas. For this, it is essential toMany Indian firms are also trying to remove the road blocks hindering the acquire coal assets abroad to market dynamics of the Gas sector. comply with the rising coal needs 4
  • 2. Basics of Thermal Power PlantWhat is thermal power?A thermal power station is a power plant in which the prime mover is steam driven. Wateris heated, turns into steam and spins a steam turbine which drives an electrical generator.After it passes through the turbine, the steam is condensed in a condenser and recycled towhere it was heated; this is known as a Rankine cycle. The greatest variation in the design ofthermal power stations is due to the different fuel sources. Some prefer to use the term energycenter because such facilities convert forms of heat energy into electricity. Some thermal powerplants also deliver heat energy for industrial purposes, for district heating, or for desalination ofwater as well as delivering electrical power.Installed thermal power capacityThe installed capacity of Thermal Power in India, as of October 31, 2012, was 140206.18 MWwhich is 66.99%of total installed capacity. Current installed base of Coal Based Thermal Power is 120,103.38 MW which comes to 57.38% of total installed base. Current installed base of Gas Based Thermal Power is 18,903.05 MW which is 9.03% of total installed capacity. Current installed base of Oil Based Thermal Power is 1,199.75 MW which is 0.57% of total installed capacity.The state of Maharashtra is the largest producer of thermal power in the country.In thermal power stations, mechanical power is produced by a heat engine that transformsthermal energy, often from combustion of a fuel, into rotational energy. Most thermal powerstations produce steam, and these are sometimes called steam power stations. Not all thermalenergy can be transformed into mechanical power, according to the second law ofthermodynamics. Therefore, there is always heat lost to the environment. If this loss is employedas useful heat, for industrial processes or district heating, the power plant is referred to as acogeneration power plant or CHP (combined heat-and-power) plant. In countries where districtheating is common, there are dedicated heat plants called heat-only boiler stations. An importantclass of power stations in the Middle East uses by-product heat for the desalination of water.The efficiency of a steam turbine is limited by the maximum temperature of the steam producedand is not directly a function of the fuel used. For the same steam conditions, coal, nuclear andgas power plants all have the same theoretical efficiency. Overall, if a system is on constantly(base load) it will be more efficient than one that is used intermittently (peak load). 5
  • Besides use of reject heat for process or district heating, one way to improve overall efficiency ofa power plant is to combine two different thermodynamic cycles. Most commonly, exhaust gasesfrom a gas turbine are used to generate steam for a boiler and steam turbine. The combination ofa "top" cycle and a "bottom" cycle produces higher overall efficiency than either cycle can attainalone.2.1 Classification of Thermal power plantBy fuel• Fossil-fuel power stations may also use a steam turbine generator or in the case of naturalgas-fired plants may use a combustion turbine. A coal-fired power station produces electricity byburning coal to generate steam, and has the side-effect of producing large amounts of sulfurdioxide which pollutes air and water and carbon dioxide, which contributes to global warming.About 50% of electric generation in the USA is produced by coal-fired power plants• Nuclear power plants use a nuclear reactors heat to operate a steam turbine generator.About 20% of electric generation in the USA is produced by nuclear power plants.• Geothermal power plants use steam extracted from hot underground rocks.• Biomass-fuelled power plants may be fuelled by waste from sugar cane, municipal solidwaste, landfill methane, or other forms of biomass.• In integrated steel mills, blast furnace exhaust gas is a low-cost, although low-energy-density, fuel.• Waste heat from industrial processes is occasionally concentrated enough to use forpower generation, usually in a steam boiler and turbine.• Solar thermal electric plants use sunlight to boil water and produce steam which turns thegenerator.By prime mover• Steam turbine plants use the dynamic pressure generated by expanding steam to turn theblades of a turbine. Almost all large non-hydro plants use this system. About 90% of all electricpower produced in the world is by use of steam turbines.• Gas turbine plants use the dynamic pressure from flowing gases (air and combustionproducts) to directly operate the turbine. Natural-gas fuelled (and oil fueled) combustion turbineplants can start rapidly and so are used to supply "peak" energy during periods of high demand,though at higher cost than base-loaded plants. These may be comparatively small units, and 6
  • sometimes completely unmanned, being remotely operated. This type was pioneered by the UK,Princetown being the worlds first, commissioned in 1959.• Combined cycle plants have both a gas turbine fired by natural gas, and a steam boilerand steam turbine which use the hot exhaust gas from the gas turbine to produce electricity. Thisgreatly increases the overall efficiency of the plant, and many new base load power plants arecombined cycle plants fired by natural gas.• Internal combustion reciprocating engines are used to provide power for isolatedcommunities and are frequently used for small cogeneration plants. Hospitals, office buildings,industrial plants, and other critical facilities also use them to provide backup power in case of apower outage. These are usually fuelled by diesel oil, heavy oil, natural gas, and landfill gas.• Micro turbines, Stirling engine and internal combustion reciprocating engines are low-cost solutions for using opportunity fuels, such as landfill gas, digester gas from water treatmentplants and waste gas from oil production.By dutyPower plants that can be dispatched (scheduled) to provide energy to a system include:• Base load power plants run nearly continually to provide that component of system loadthat doesnt vary during a day or week. Base load plants can be highly optimized for low fuelcost, but may not start or stop quickly during changes in system load. Examples of base-loadplants would include large modern coal-fired and nuclear generating stations, or hydro plantswith a predictable supply of water.• Peaking power plants meet the daily peak load, which may only be for a one or two hourseach day. While their incremental operating cost is always higher than base load plants, they arerequired to ensure security of the system during load peaks. Peaking plants include simple cyclegas turbines and sometimes reciprocating internal combustion engines, which can be started uprapidly when system peaks are predicted. Hydroelectric plants may also be designed for peakinguse.• Load following power plants can economically follow the variations in the daily andweekly load, at lower cost than peaking plants and with more flexibility than base load plants.Non-dispatch able plants include such sources as wind and solar energy; while their long-termcontribution to system energy supply is predictable, on a short-term (daily or hourly) base theirenergy must be used as available since generation cannot be deferred. Contractual arrangements(“take or pay") with independent power producers or system interconnections to other networksmay be effectively non-dispatch able. 7
  • Thermal power plants can deploy a wide range of technologies. Some of the majortechnologies include: Steam cycle facilities (most commonly used for large utilities); Gas turbines (commonly used for moderate sized peaking facilities); Cogeneration and combined cycle facility (the combination of gas turbines or internal combustion engines with heat recovery systems); and Internal combustion engines (commonly used for small remote sites or stand-by power generation).India has an extensive review process, one that includes environment impact assessment, prior toa thermal power plant being approved for construction and commissioning. The Ministry ofEnvironment and Forests has published a technical guidance manual to help project proposersand to prevent environmental pollution in India from thermal power plants.Schematic Diagram of Thermal power plant.Typical diagram of a coal-fired thermal power station1. Cooling tower 10. Steam Control valve 19. Superheater2. Cooling water pump 11. High pressure steam turbine 20. Forced draught (draft) fan 8
  • 3. transmission line (3-phase) 12. Deaerator 21. Reheater4. Step-up transformer (3-phase) 13. Feedwater heater 22. Combustion air intake5. Electrical generator (3-phase) 14. Coal conveyor 23. Economiser6. Low pressure steam turbine 15. Coal hopper 24. Air preheater7. Condensate pump 16. Coal pulverizer 25. Precipitator8. Surface condenser 17. Boiler steam drum 26. Induced draught (draft) fan9. Intermediate pressure steam 18. Bottom ash hopper 27. Flue gas stackturbine2.2 Working of Thermal power plantFeed water heaterA feed water heater is a power plant component used to pre-heat water delivered toa steam generating boiler. Preheating the feed water reduces the irreversibility involved in steamgeneration and therefore improves the thermodynamic efficiency of the system. This reducesplant operating costs and also helps to avoid thermal shock to the boiler metal when the feedwater is introduced back into the steam cycle.BoilerA boiler is a closed vessel in which water or other fluid is heated. The heated or vaporized fluidexits the boiler for use in various processes or heating applications.Steam condensingThe condenser condenses the steam from the exhaust of the turbine into liquid to allow it to bepumped. If the condenser can be made cooler, the pressure of the exhaust steam is reduced andefficiency of the cycle increases.Electrical GeneratorIn electricity generation, an electric generator is a device that converts mechanicalenergy to electrical energy. 9
  • Steam TurbineA steam turbine is a mechanical device that extracts thermal energy from pressurized steam,and converts it into rotary motion.2.3Advantages of Thermal Power 1. The fuel used is quite cheap. 2. Less initial cost as compared to other generating plants. 3. It can be installed at any place irrespective of the existence of coal. The coal can be transported to the site of the plant by rail or road. 4. It requires less space as compared to Hydro power plants. 5. Cost of generation is less than that of diesel power plants. 6. They can be located very conveniently near the load centers. 7. Does not require shielding like required in nuclear power plant 8. Unlike nuclear power plants whose power production method is difficult, for thermal power plants it is easy. 9. Transmission costs are reduced as they can be set up near the industry. 10. The portion of steam generated can be used as process steam in different industries. 11. Steam engines and turbines can work under 25%of overload capacity. 12. Able to respond changing base loads without difficulty.2.4 Disadvantagesof Thermal Power 1. It pollutes the atmosphere due to production of large amount of smoke and fumes. 2. Large amounts of water are required. 3. Takes long time to be erected and put into action. 4. Maintenance and operating costs are high. 10
  • 5. With increase in pressure and temperature, the cost of plant increases. 6. Troubles from smoke and heat from the plant, disposal of ash.2.5Efficiency:The energy efficiency of a conventional thermal power station, considered as salable energy as apercent of the heating value of the fuel consumed, is typically 33% to 48%. This efficiency islimited as all heat engines are governed by the laws of thermodynamics. The rest of the energymust leave the plant in the form of heat. This waste heat can go through a condenser and bedisposed of with cooling water or in cooling towers. If the waste heat is instead utilizedfordistrict heating, it is called co-generation. Important classes of thermal power station areassociated with desalination facilities; these are typically found in desert countries with largesupplies ofnatural gas and in these plants, freshwater production and electricity are equallyimportant co-products.The Carnot efficiency dictates that higher efficiencies can be attained by increasing thetemperature of the steam. Sub-critical fossil fuel power plants can achieve 36–40%efficiency. Super critical designs have efficiencies in the low to mid 40% range, with new "Ultracritical" designs using pressures of 4400 psi (30.3 MPa) and multiple stage reheat reaching about48% efficiency. Above the critical point forwater of 705 °F (374 °C) and 3212 psi (22.06 MPa),there is no phase transition from water to steam, but only a gradual decrease indensity.Current nuclear power plants must operate below the temperatures and pressures that coal-firedplants do, since the pressurized vessel is very large and contains the entire bundle of nuclear fuelrods. The size of the reactor limits the pressure that can be reached. This, in turn, limits theirthermodynamic efficiency to 30–32%. Some advanced reactor designs being studied, such asthe Very high temperature reactor, advanced gas-cooled reactor and super critical water reactor,would operate at temperatures and pressures similar to current coal plants, producing comparablethermodynamic efficiency. 11
  • Heat rateA form of expressing efficiency of an engine or turbine. The fuel heating value consumed perunit of useful output (usually electrical output). Common unit is kJ/kWh. To convert toefficiency divide by 3600 and invert.Heat Rate (Generated) (kJ/kWh)Quantity fuel (kg) * higher heating value of fuel consumed (kJ/kg) divided by:Total energy generated (kWh)Heat Rate (gen) is related to Efficiency (gen) by:Heat Rate (gen) (kJ/kWh) = 3600 * 100 divided by:/ Efficiency (gen) (%)Heat Rate (Sent Out) (kJ/kWh)Quantity fuel (kg) * higher heating value of fuel consumed (kJ/kg) divided by:/ Total energygenerated (kWh) - Total auxiliary energy (kWh)Heat Rate (s/o) is related to Efficiency (s/o) byHeat Rate (s/o) (kJ/kWh) = 3600 * 100 ./ Efficiency (s/o) (%) 12
  • 2.6Power Companies in India.The following 58 pages are in this category, out of 58 totals. This list may not reflect recent changes (learnmore).A G N Nuclear Power Corporation of Adani Power Gujarat Urja Vikas Nigam India Andhra Pradesh Central Power H ODistribution Company Andhra Pradesh Power Haryana Power Generation Orissa Power GenerationGeneration Corporation Corporation Corporation Astonfield I PB Indraprastha Power Generation Paschim Gujarat Vij Bombay Electric Supply & J Punjab State Power CorporationTramways Company Limited Brihanmumbai Electric Supply Jindal Steel and Power Rand Transport British Electric Traction Rajasthan Rajya Vidyut Utpadan JSW EnergyCompany NigamC K Reliance Infrastructure Karnataka Power Corporation Rural Electrification Corporation CESC Limited Limited Limited Chamundeshwari Electricity L SSupply Corporation Limited Chhattisgarh State Power Lanco Infratech Sterlite Energy LimitedGeneration Company Limited List of electricity organisations in Clarke Energy T India Tamil Nadu Generation andD M Distribution Corporation Limited Tamil Nadu Transmission Dabhol Power Company Madhya Gujarat Vij Corporation Limited Dakshin Gujarat Vij Company Madhya Pradesh Power Tata PowerLtd. Generation Company Limited Dakshin Haryana Bijli Vitran Maharashtra State Electricity TNEBNigam Distribution Company Limited Maharashtra State Power Damodar Valley Corporation Torrent Power Generation Company Limited Mangalore Electricity Supply Transmission Corporation of Delhi Transco Limited Company Limited Andhra Pradesh 13
  • E MSPL Limited U Essar Energy N Uttar Gujarat Vij Uttar Haryana Bijli VitranG Neyveli Lignite Corporation Nigam Uttar Pradesh Rajya Vidyut User talk:Gkd1981 NHPC Limited Utpadan Nigam Gujarat State Electricity North Eastern Electric Power WCorporation Limited Corporation Limited Gujarat State Energy NSPCL Welspun EnergyGeneration NTPC Limited Bhavini 14
  • 3. Prospects of Setting up a Thermal Power PlantThe current and future projected cost of new electricity generation capacity is a critical input intothe development of energy projections and analyses. The cost of new generating plants plays animportant role in determining the mix of capacity additions that will serve growing loads in thefuture. New plant costs also help to determine how new capacity competes against existingcapacity, and the response of the electricity generators to the imposition of environmentalcontrols on conventional pollutants or any limitations on greenhouse gas emissions.Planning of Power Plant involves decision ontwo basic parameters: 1. Total power output to be installed (e.g. 1000 MW)  Installed capacity is determined from: • Estimated Demand: - Before setting up a powerplant, we need to critically analyze demand which gives us the idea to determine capacity which needs to be installed. The installation capacity should match the demand and hence estimation of demand is the critical fact while setting up a power plant. • Growth of Demand anticipated: - While determining demand, future prospects needs to be considered so that the return on capital would be maximized and future demand could be met easily. • Reserve Capacity required:- Considering the various type of demand in a market how much reserve capacity is required to be installed is determined and hence this will help in determining installation capacity. 2. Size of generating units (e.g. 4 units of 250 MW each)  Size of the generating units will depend on: • Variation of Load (Load Curve):- During the different hour of the day and in various seasons the demand varies, so the load curves. Now the number of units has to be determined to run the operations optimally and meeting the requirement daily. • Minimum start-up and shut down periods of the units • Maintenance programme planned 15
  • Above are few factors which one will look before setting up power plant. After taking decisionto setup a plant following are the important aspect which plays an important role in setting uppower plant.3.1 LOCATIONSelecting a proper site for a thermal power plant is vital for its long term efficiency and a lotmany factors come into play when deciding where to install the plant. Of course it may not bepossible to get everything which is desirable at a single place but still the location should containan optimum mix of the requirements for the settings to be feasible for long term economicjustification of the plant.As the name implies the power plant is meant for generating power which obviously means thatit will consume huge quantities of fuel. The exact quantity would depend on the size of the plantand its capacity but it is a general fact that ample quantities of fuel must be available either in thevicinity or it should be reasonably economical to transport the fuel till the power plant. Sincemost thermal power plants use coal (they can use other fuels as well) it must be ensured thatsufficient coal is available round the clock. Just to give a rough idea a power plant with 1000MW capacity approximately would require more than ten thousand tons of coal per day hencethe necessity for continuous supply and storage capability of coal in the power station.In general, both the construction and operation of a power plant requires the existence of someconditions such as water resources and stable soil type. Still there are other criteria that althoughnot required for the power plant, yet should be considered because they will be affected by eitherthe construction or operation of the plants such as population and protected areas. The followinglist corers most of the factors that should be studied and considered in selection of proper sitesfor power plant construction:Transportation network: Easy and enough access to transportation network is required in bothpower plant construction and operation periods.Gas pipe network: Vicinity to the gas pipes reduces the required expenses.Power transmission network: To transfer the generated electricity to the consumers, the plantshould be connected to electrical transmission systemTherefore the nearness to the electric network can play a roll.Geology and soil type: The power plant should be built in an area with soil and rock layers thatcould stand the weight and vibrations of the power plant. 16
  • Earthquake and geological faults: Even weak and small earthquakes can damage many parts ofa power plant intensively. Therefore the site should be away enough from the faults and previousearthquake areas.Topography: It is proved that high elevation has a negative effect on production efficiency ofgas turbines. In addition, changing of a sloping area into a flat site for the construction of thepower plant needs extra budget. Therefore, the parameters of elevation and slope should beconsidered.Rivers and floodways: obviously, the power plant should have a reasonable distance frompermanent and seasonal rivers and floodways.Water resources: For the construction and operating of power plant different volumes of waterare required. This could be supplied from either rivers or underground water resources.Therefore having enough water supplies in defined vicinity can be a factor in the selection of thesite.Environmental resources: Operation of a power plant has important impacts on environment.Therefore, priority will be given to the locations that are far enough from national parks, wildlife,protected areas, etc.Population centers: For the same reasons as above, the site should have an enough distancefrom population centers.3.2WASTE MANAGEMENTEnergy requirements for the developing countries in particular are met from coal-based thermalpower plants. The disposal of the increasing amounts of solid waste from coal-fired thermalpower plants is becoming a serious concern to the environmentalists. Coal ash, 80% of which isvery fine in nature and is thus known as fly ash is collected by electrostatic precipitators instacks. In India, nearly 90 mt of fly ash is generated per annum at present and is largelyresponsible for environmental pollution. In developed countries like Germany, 80% of the flyash generated is being utilized, whereas in India only 3% is being consumed. This articleattempts to highlight the management of fly ash to make use of this solid waste, in order to saveour environment.COAL-based thermal power plants have been a major source of power generation in India,where 75% of the total power obtained is from coal-based thermal power plants. The coal reserveof India is about 200 billion tonnes (BT) and its annual production reaches 250 million tonnes 17
  • (mt) approximately. About 70% of this is used in the power sector. In India, unlike in most of thedeveloped countries, ash content in the coal used for power generation is 30–40%. High ash coalmeans more wear and tear of the plant and machinery, low thermal efficiency of the boiler,slogging, choking and scaling of the furnace and most serious of them all, generation of a largeamount of fly ash. India ranks fourth in the world in the production of coal ash as by-productwaste after USSR, USA and China, in that order. Fly ash is defined in Cement and ConcreteTerminology (ACI Committee 116) as the ‘finely divided residue resulting from the combustionof ground or powdered coal, which is transported from the fire box through the boiler by fluegases’. Fly ash is fine glass powder, the particles of which are generally spherical in shape andrange in size from 0.5 to 100 gm. Fly ash is classified into two types according to the type of coalused. Anthracite and bituminous coal produces fly ash classified as class F. Class C fly ash isproduced by burning lignite or sub-bituminous coal. Class C fly ash has self-cementingproperties.3.3Effluent and disposalDisposal and management of fly ash is a major problem in coal-fired thermal power plants. Flyash emissions from a variety of coal combustion units show a wide range of composition. Allelements below atomic number 92 are present in coal ash. A 500 MW thermal power plantreleases 200 mt SO2, 70 t NO2 and 500 t fly ash approximately every day. Particulate matter(PM) considered as a source of air pollution constitutes fly ash. The fine particles of fly ash reachthe pulmonary region of the lungs and remain there for long periods of time; they behave likecumulative poisons. The submicron particles enter deeper into the lungs and are deposited on thealveolar walls where the metals could be transferred to the blood plasma across the cellmembrane. The residual particles being silica (40–73%) cause silicosis. All the heavy metals (Ni,Cd, Sb, As, Cr, Pb, etc.) generally found in fly ash are toxic in nature.Fly ash can be disposed-off in a dry or wet state. Studies show that wet disposal of this wastedoes not protect the environment from migration of metal into the soil. Heavy metals cannot bedegraded biologically into harmless products like other organic waste. Studies also show thatcoal ash satisfies the criteria for landfill disposal, according to the Environmental Agency ofJapan2. According to the hazardous waste management and handling rule of 1989, fly ash isconsidered as non-hazardous. With the present practice of fly-ash disposal in ash ponds (gener-ally in the form of slurry), the total land required for ash disposal would be about 82,200 ha bythe year 2020 at an estimated 0.6 ha per MW. Fly ash can be treated as a by-product rather thanwaste. 18
  • 3.4 Water Balance and Water Conservation in Thermal Power StationsIn thermal power stations consumption of auxiliary power, specific coal consumption, specificoil consumption and heat rate are generally monitored. Many at the power plants may not knowthe specific water consumption, except in percentage terms DM water makeup. In the recentpast, the water cost has gone up by more than 70 times in many states. A typical super thermalpower station of 2100 MW pays around Rs. 10 crore towards water bill for the raw water alone,excluding what is paid to the pollution control boards. There is lot of prudence in monitoring thespecific water consumption in terms of liter/kWh. The specific water consumption of coal basedpower plants varies between 3.5 – 8 liters/kWh. BY systematic water audit, one can reduce waterconsumption to the tune of 30-40 percent. Water conservation also leads to reduction of auxiliarypower consumption, since there is close nexus between water and energy. 19
  • 4. Clearance Required Setting up a Thermal Power Plant 20
  • 4.1 Some basic Problems for Thermal Power plant Planning. 1. Fuel quality & availability a. Coal quality & availability constraints 2. Coal beneficiation 3. Power generation technology 4. Clean coal based technologies 5. Land accusation Problem 6. Logistic route Rail/ Road, pipelines, port etc (for fuel, water, ash etc) 7. Power evacuation route (Electricity Grid) 8. Water source. 9. Price of Fuel a. Volatility of coal price. 10. Environmental clearance. 11. Benchmark a. Resultant cost can at best be applied only as a prudence check rather than be used to determine the tariff. Model should not replace the price discovery model based on ICB tendering process b. Emphasis now is being laid on tariff based competitive bidding; as such thisbenchmark study may serve limited purpose. c. Technological transfer price impact: Impact of advisory issued by CEA in February 2010 regarding incorporation of the condition of setting up of phased indigenous manufacturing facilities in the bids while sourcing supercritical units would require accounting for increase in cost on such issues. d. Sample Size for 600, 660 & 800 MW /Limited data availability for 600/660/800 MW/Extrapolation done to derive costs. 12. Civil Works 13. Indices used for calculation of Escalation do not match with indices used by largest manufacturer (BHEL) and utility (NTPC). 14. Scaling down factors in case of Greenfield vs. Brownfield projects/Additional units 10 at one location. 15. It is not clear whether the project specific Mega/non mega status have been factored in the analysis of price. Electro Static Precipitator package considered is a part of Steam Generator package or is excluded. Cost of transportation, insurance, statutory fees paid towards Indian Boiler Regulations, IR etc is included or otherwise. 12 Benchmark data for Turbine Generator and Boiler are based on Turbine Inlet parameter as 247 bar, 537/565 deg centigrade. However if any developer goes in for higher parameter e.g. 565/593 deg centigrade suitable factor to be applied overbenchmark cost. 21
  • 16. 7 Providing options for dry fly ash disposal (100%), high Concentration Slurry System 100%). Suitable weightage for distance beyond 5 km, lower slabs of Calorific value, price ceiling impact may be considered, Categorization of seismic zone, Type of chimney- single flue/multi flue, consideration of auxiliary boiler etc. 17. Change in evacuation voltage level from 400KV to 765KV results in significant increase in switchyard cost i.e. per bay cost almost trebles. 5. Environmental checklist for Thermal Power PlantBefore setting up a thermal power plant most critical job is EIA study. Environmental ImpactAssessment (EIA) is a process of identifying, predicting, evaluating and mitigating thebiophysical, social, and other relevant effects of development proposals prior to major decisionsbeing taken and commitments made.The basic tenets of this EIA Notification could be summarized into following: Pollution potential as the basis for prior environmental clearance instead of investment criteria; and Decentralization of clearing powers to the State/Union Territory (UT) level Authorities for certain developmental activities to make the prior environmental clearance process quicker, transparent and effective mechanism of clearance.5.1Tools for assessment and analysis Risk assessment Life cycle assessment Total cost assessment Environmental audit/statement Environmental benchmarking Environmental indicatorsTools for action Environmental policy Market-based economic instruments o Pollution charge o Tradable permits o Market barrier reductions 22
  • o Government subsidy reduction Innovative funding mechanism EMS and ISO certification Total environmental quality movement Eco-labelling Cleaner production 4-R concept Eco-efficiency Industrial eco-system or metabolism Voluntary agreements5.2 Guidelines of central electricity authority [CEA], government of India,for site selection of coal-based thermal power stationsThe choice of location is based on the following:– Nearness to coal source;– Accessibility by road and rail;– Availability of land, water and coal for the final installation capacity;– Coal transportation logistics;– Power evacuation facilities;– Availability of construction material, power and water;– Preliminary environmental feasibility including rehabilitation and resettlementrequirements, ifany;Land requirement for large capacity power plant is about 0.2 km2 per 100 MW for the mainpower house only excluding land for water reservoir (required if any). The land for housing is taken as 0.4 km2 per project. Land requirement for ash pond is about 0.2 km2 per 100 MW considering 50% of ash utilization. Land for ash pond is considered near the main plant area (say 5 to 10 km away). In case of non-availability of low lying ash pond area at one place, the possibility of having two areas in close proximity is considered. Water requirement is about 40 cusecs per 1000 MW. First priority is given to the sites those are free from forest, habitation and irrigated/agricultural land. Second priority is given to those sites that are barren, i.e., wasteland, intermixed with any other land type, which amounts to 20% of the total land identified for the purpose. Location of thermal power station is avoided in the coal-bearing area. Coal transportation is preferred by dedicated marry-go-round (MGR) rail system. The availability of corridor for the MGR need to be addressed while selecting the sites. 23
  • 5.3 Guidelines for site selection of coal-based thermal power stations setbythe MoEF Locations of thermal power stations are avoided within 25 km of the outer peripheryof the following:– Metropolitan cities;– National park and wildlife sanctuaries;– Ecologically sensitive areas like tropical forest, biosphere reserve, important lakeand coastalareas rich in coral formation; The sites should be chosen in such a way that chimneys of the power plants does not fall within the approach funnel of the runway of the nearest airport; Those sites should be chosen which are at least 500 m away from the flood plain of river system; Location of the sites are avoided in the vicinity (say 10 km) of places of archaeological, historical, cultural/religious/tourist importance and defense installations; Forest or prime agriculture lands are avoided for setting up of thermal power houses or ash disposal 6. EIA study report.6.1 Project CycleThe generic project cycle including that of Thermal Power Plant has six main stages:1. Project concept2. Pre-feasibility3. Feasibility4. Design and engineering5. Implementation6. Monitoring and evaluationIt is important to consider the environmental factors on an equal basis with technical andeconomic factors throughout the project planning, assessment and implementation phases.Environmental consideration should be introduced at the earliest in the project cycle and must bean integral part of the project pre-feasibility and feasibility stage. If the environmentalconsiderations are given due respect in site selection process by the project proponent, thesubsequent stages of the environmental clearance process would get simplified and would alsofacilitate easy compliance to the mitigation measures throughout the project life cycle.A project’s feasibility study should include a detailed assessment of significant impacts and theEIA include a detailed prediction and quantification of impacts and delineation of EnvironmentalManagement Plan (EMP). Findings of the EIA study should preferably be incorporated in theproject design stage so that the project is studied, the site alternatives are required and necessarychanges, if required, are incorporated in the project design stage. This practice will also help the 24
  • management in assessing the negative impacts and in designing cost-effective remedialmeasures. In general, EIA enhances the project quality and improves the project planningprocess.6.2Project Analysis1) Executive summary of the project.2) Justification for selecting the proposed unit size.3) Land requirement for the project including its break up for various purposes, its availabilityand optimization. Norms prescribed by CEA should be kept in view.4) Details of proposed layout clearly demarcating various units within the plant.5) Complete process flow diagram describing each of the unit processes and operations,alongwith material and energy inputs & outputs (material and energy balance).6) Details on requirement of raw materials, its source and storage at the plant.7) Fuel analysis report (sulphur, ash content and mercury) including details of auxiliaryfuel, ifany. Details like quantity, quality, storage etc.,8) Quantity of fuel required its source and transportation, a confirmed fuel linkage/ copyof theMoU.9) Source of water and its availability. Proof regarding availability of requisite quantityof waterfrom the competent authority.10) Details on water balance including quantity of effluent generated, recycled & reused.Effortsto minimize effluent discharge and to maintain quality of receiving waterbody.11) Details of effluent treatment plant, inlet and treated water quality with specificefficiency ofeach treatment unit in reduction in respect of all concerned/regulatedenvironmental parameters.12) Location of intake and outfall points (with coordinates) based on modeling studies.Details of modeling and the results obtained. It may be kept in view that the intakeand outfallpoints are away from the mangroves.13) Examine the feasibility of zero discharge. In case of any proposed discharge, itsquantity,quality and point of discharge, users downstream, etc.14) Explore the possibility of cooling towers installation. Details regarding the same.15) Details regarding fly ash utilization as per new notification16) Detailed plan of ash utilization / management.17) Details of evacuation of ash.18) Details regarding ash pond impermeability and whether it would be lined, if so detailsof thelining etc.19) Details of desalination plant and disposal of sludge.20) Details of proposed source-specific pollution control schemes and equipment to meetthenational standards.21) Details of the proposed methods of water conservation and recharging.22) Management plan for solid/hazardous waste generation, storage, utilization anddisposal.23) Details regarding infrastructure facilities such as sanitation, fuel storage, restroom,etc. to theworkers during construction and operation phase. 25
  • 24) In case of expansion of existing industries, remediation measures adopted to restoretheenvironmental quality if the groundwater, soil, crop, air, etc., are affected and adetailedcompliance to the prior environmental clearance/consent conditions.25) Any litigation pending against the project and /or any direction /order passed by anyCourt ofLaw related to the environmental pollution and impacts in the last two years,if so, details thereof.Description of the EnvironmentAnticipated Environmental Impacts and Mitigation MeasuresAnalysis of alternative resources and technologiesEnvironmental Monitoring ProgramAdditional StudiesEnvironmental Management Plan 26
  • 7. CONCLUSIONPower projects are necessary not only for the economic development but for the growth ofinfrastructure in any country. Starting a project from grass root level to the full-fledgedproduction stage requires lots of time and resources which require proper planning and optimalutilization of resources. Besides all this tedious work, getting clearances to start the project andfulfil the required resources are important concern for project owners. These requirement areland, water, material, men, machinery, etc. and clearances which require lot of work to becompleted before execution of project.After EA 2003, power sector has faced reforms and restructuring. Many new policies ofgovernment are introduced due to which escalation in power production has been seen in recentpast. Policies give an opportunity for private player to enter and arrange their requirement bythemselves which helps in accelerating the projects. Other arrangements like SPV, in case ofUMPP, are nice option to get clearances and bidders get assured for certain requirement.Special purpose vehicles (SPV), or shell companies, have been set up as wholly ownedsubsidiaries of the Power Finance Corporation for each UMPP that will be built. SPV obtainsvarious clearances, water linkage, coal mine allocation (for domestic coal based projects) etc forthe project. The SPV also initiates action for land acquisition in the name of the SPV, selects thedeveloper through a tariff based competitive bidding process and finally transfers the SPV to theidentified developer along with the various clearances, tie ups, etc. The developer is thenresponsible to build, own, and operate ("BOO" in economic parlance) these UMPP plants.Hence, such arrangement as mentioned above are recommended creating confidence for biddersand getting clearance from PFC owned company. This ensures financial arrangements to startpower plant and completion of project. It needs plenty of steps to travel the journey from hereand everyone is expecting the pace.Certainly, India has to walk a mile before it takes a hold. 27
  • 8. REFERENCE1. Indian infrastructure research, (August 2012). Energy reports. PowerLine magazine 11. Volume 16, N0.2.2. Power trading, (August 2012). Discom financials. PowerLine magazine 11. Volume 16, N0.2.3. Indian Electricity scenario. About the sector, retrieved on November 18, 2012,fromhttp://www.powermin.nic.in/JSP_SERVLETS/internal.jsp4. Training and Research. National training policy for power sector, retrieved on November 22, 2012,fromhttp://www.powermin.nic.in/JSP_SERVLETS/internal.jsp5. British Electricity International (1991). Modern Power Station Practice: incorporating modern power systempractice (3rd Edition (12 volume set) ed.). Pergamon. ISBN 0-08-040510-X.6. Indian power sector review http://indianpowersector.com/home/power-station/thermal-power-plant/7. Central Electricity Authority reports on December 2012 fromhttp://www.cea.nic.in/reports/proj_mon/broad_status.pdf8. Central electricity Regulatory commission.(June 2012). Benchmark Capital Cost (Hard cost) for Thermal PowerStations with Coal as Fuel. http://www.cercind.gov.in/2012/regulation/Benchmark_Capital_Cost_for_TPS.pdf9. Planning Commission of IndiaReports Five year plans reports. http://planningcommission.nic.in/index.php10. Ministry of Power Reports..http://powermin.nic.in/ 28