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Chapter 1..., , Introduction to Power Plants, , , , , , [weightage of Marks = 12, Teaching Hours = 08], , 1.1 World and National Scenario of Demand and Supply of Energy., , 1.2. Introduction to Power Plants: Their Importance and Types., , 1.3. Hydroelectric Power Plant: Classification, General Arrangement, Operating Principle, Advantages, , and Limitations, Maintenance., , 1.4 Diesel Power Plant: Introduction, Components, Advantages and Limitations, Diesel Generating Set,, , Mele N EM Ese, , Maintenance., , After reading this chapter, the students will able to,, e Explain energy conversion in the given power plant., , ¢ Identify elements of the given Hydro and Diesel power plant(s)., , ¢ Explain maintenance procedure of the given power plants., , , , , , , , 1.1 ENERGY OR POWER SCENARIO IN INDIA ~, , , , , , In world ranking, India is the 11" greatest energy, Producer accounting for about 2% of total world, energy production., , At the same time, India is ranking world's 6", greatest energy consumer, accounting for 3% of, total energy consumption annually in the world., Therefore, India is the net energy importer due, to large imbalance between production and, consumption., , The sector wise energy consumption for India is, as shown in Fig. 1.1 ie. Industry 49%,, Transportation 22%, Residential 10%, Agricultural, , , , Industry, , , , Transport, , , , , Others, 14%, , , , Fig. 1.1: Sector wise energy consumption in India, , 5% and other as 14%., , * The electrical power generation from various energy resources are given in tabulated form as under:, , , , , , , , , , , , , , , , , , , , , , Resource Production (MW) Percentage Share, , Thermal: Coal 75 x 10? 52.44%, Gas 15x10 10.48%, Diesel 1x10 0.699%, Nuclear 4x10? 2.79%, Hydro 36 x 10° 25.17%, Renewable energy resources 12 x 10° 8.39%, , Total 143 x 10° 100%, , , , , , , , (1.4), , Scanned with CamScanner
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Power Plant Engineering 4.2 Introduction to Power Plants, , , , , , , , 74.2 WORLD OR GLOBAL ENERGY OR POWER SCENARIO, , , , , , Globally, the primary energy resources consumed to meet the increasing demands of energy are coal, oil,, gas etc. ‘, , Primary energy resources are those, which are found or stored in nature. For example: Coal, Oil,, Natural gas and biomass., , 1.2.1 Primary Energy Reserves at World Level, , , , , , , , , , , , The primary reserves of various major countries are given below:, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , 1. Coal:, © United states of America (USA) has the largest share of the global energy reserves. The reserve of, coal at USA is almost 25.4%., Russia had 15.9% reserve of coal., China had 11.6% reserve of coal., India had 8.6% reserve of coal., 2. Oil:, o The oil reserves are measured in barrel. One barrel of oil is approximately equal to 160 litres., o Saudi Arabia has the largest share of the oil reserve with almost 23%., o The Arabian countries have largest reserves of oil as compared to other countries., 3. Gas:, o The Russian Federation has the largest share of the gas reserve with almost 27%., co The Russian Federation has gas reserves equivalent to 365.2 million tonnes of oil., o World oil and gas.reserves are estimated to last for just 45 years and 65 years respectively., 1.2.2 Global or World Level Primary Energy Consumption, ¢ The global primary energy consumption at the end of 2015 was equivalent to 11000 million tonnes of oil, equivalent. ‘, « The primary energy consumption for few of the developed and developing countries are shown in, Table 1.1., Table 1.1: Primary Energy Consumption of Major Countries, (In million tonnes oil equivalent), Country |. oil Natural gas Coal |: Nuclear Hydro., _ | electric (|< ‘electric, U.S.A. 914.3 566.8 $73.9 182.9 60.9, Canada 96.4 78.7 31.0 16.8 68.6, France 94.2 39.4 12.4 99.8 148, Russian 124.7 365.2 1113 34.0 35.6, Federation, U.K. 76.8 85.7 39.1 20.1 13 223.2, India 113.3 27.1 185.3 4.1 15.6 345.3, China 275.2 29.5 799.7 98 64.0 11783, Japan 248.7 68.9 112.2 52.2 22.8 504.8, , , , Scanned with CamScanner
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Power Plant Engineering 13 Introduction to Power Plants, , Fig. 1.2 shows the percentage wise consumption of various primary energy resources at world level., , Renewables, , Biomass 4%, Solarheat 0.5%, Geothermal 0.2%, Solar PV 0.05%, Hydro 3%, Wind 0.3%, Biofuel 0.2%, , , , Fig. 1.2, , , , , , , , 1.3 IMPORTANCE OF POWER PLANTS, , , , Bulk electric power is generated by special plants known as power plants or generating stations., , A generating station consists of a prime mover coupled to an alternator/generator to produce electric, power., , The prime mover converts different energy forms like kinetic energy, potential energy, chemical energy,, into mechanical energy. ., , The alternator/generator converts the mechanical energy to electrical energy., , In the modern scenario, the need for electricity is increasing very rapidly., , Electric power is considered as the heart of any industry., , Electricity is used in our day-to-day life for lighting, heating, cooling, lifting, cooking and so on., Therefore, it is necessary to produce electricity in large scale and it should also be economical., , The large-scale power production could be achieved only by means of suitable power producing units, like power plants., , The most commonly used power plants are Steam/Thermal, Gas, Diesel, Hydroelectric and Nuclear power, plants., , The main aspects considered, while constructing or designing a power plant is the selection of proper, location and appropriate equipments for the plant, such that, maximum output is achieved., , The generated power must also be cost effective, reliable and fairly uninterrupted., , , , , , 1.4 CLASSIFICATION OR TYPES OF POWER PLANTS, , , , Power plant is an assembly of equipments, which produces and delivers mechanical and electrical, energy., Power plant may be classified in the following manner., 1. On the basis of source of energy:, (i) Steam power plants of condensing and non-condensing type., (i) Hydroelectric power plants., (iii), Nuclear power plants., (iv) Gast turbine power plants., (v) Diesel power plants., (vi) Nuclear power plants., (vii) Tidal power plants., (viii) Wind power plants., , Scanned with CamScanner
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Power Plant Engineering 1.4, , 2., , On the basis of conventional or non-conventional sources:, (i) Conventional sources:, (a) Thermal power plants (Steam, Diesel, and Gas)., (b) Hydro power plant., (c) Nuclear power plant., (ii) Non-conventional sources:, (a) Tidal power plant., (b) Wind power plant., (c) Solar power plant., (d) Geo-thermal power plant., On the basis of nature of load:, (i) Peak load plant., (ii) Base load plant., (iii) Stand-by plant., On the basis of location:, (i) Central power station., (ii) Isolated power station., , Introduction to Power Plants, , , , , , 41.5 CLASSIFICATION OF HYDROELECTRIC POWER PLANTS, , , , , , Hydroelectric power plants are classified in the following manner:, , 4., , According to the water head available:, , (i) High head power plants: They work under a head of more than 100 m. For example: Pelton, , wheel water turbine power plant., , (ii) Medium head power plants: They work under a head between 40 m to 100 m. For example:, , Francis water turbine power plant., , (iii) Low head hydro power plants: They work under a head lower than 40 m. For example: Kaplan, , water turbine power plant., According to discharge quantity:, , (i) Pumped storage plants: Water is stored in tailrace reservoir. When demand is low, water is, pumped to the head reservoir and when demand is high, the stored water is used to produce, , shaft work by the turbine., , (ii) Run-off river plants: They store a few hours’ supply of water, so that, when the river flow, exceeds the amount required by the plant, the stored water can be utilized during the peak, , demand. The velocity of water due to high slope of river is enough to produce power., , (iii) Storage reservoir: During rainy season, water is stored in the reservoir. This stored water is, utilized during other seasons, when the flow in river is low., , According to type of small hydroelectric power plants:, , (i) Mini hydroelectric power plants: Mini hydroelectric power plants range between a high of 10, , MW and a low of 100 kW., , (ii) Micro hydroelectric power plants: Micro hydroelectric power plants have a capacity of under, , 100 kW., According to the nature of load:, (i) Base load hydroelectric power plant., (ii) Peak load hydroelectric power plant., , 1.6 HYDROELECTRIC POWER PLANT, , Principle of Working:, , In hydroelectric power plants, the potential energy of water is utilized to run the hydraulic turbines,, which in turn, runs an electric generator to convert the mechanical energy of turbine into electric energy., In hydroelectric power plants, the water is collected and artificially stored by constructing dams across, , the flowing streams. This potential energy of water is converted into mechanical work and ultimately into, electrical energy., , Scanned with CamScanner, , a
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Power Plant Engineering 1.5 Introduction to Power Plants, , * The power developed by the hydraulic turbine depends on the quantity of water and the head of water, , available., «The quantity of water available at the selected site depends upon the rainfall in that area., , * Therefore, these plants have to be located, where the water resources are available in abundant quantity, at sufficient head., , Construction Features of Hydroelectric Power Plant:, , « The main components of the hydro-electric power plant and their functions are as follows:, , 1. Reservoir:, © Areservoir is provided to store water during rainy season and supplies the same in dry season., o Alarge amount of water is collected during rainy season in a reservoir behind a dam., , © The water from the reservoir is used to run the hydraulic turbine., , 2. Dam:, o Damis constructed across a river to store the water. Therefore, it acts ag a water reservoir., o Itis constructed with masonry or R.C.C., © It provides necessary potential energy to nozzles of a turbine., o Top surface of water in dam is called as head race. It represents the gross head., 3. Trash rack: 5, 0 Trash rack is made up of steel bars. It is provided to prevent entry of debris into the intake from dam, or from forebay. “, o Any debris into the intake water pipe may damage the turbine runners or choke the nozzles of an, impulse turbine., 4. Gate:, o The gate is provided for controlling of flow of water from reservoir to hydraulic turbine through, penstock. . :, 0 Itis closed, when maintenance of system is required., 5. Surge tank:, o Asurge tank is used to provide better regulation of water pressure in the system., o Working of surge tank is discussed with details in the next article., 6. Waterway and Penstock: :, o Awaterway is used to carry water from the dam to the power house., © Itincludes canal and penstock (closed pipe) or a tunnel., © Penstock is a circular pipe having very long length laid down from dam up to turbine room., o Also, large diameter for penstock pipe is selected, so that, maximum discharge (high flow rate) can, be obtained at outlet of penstock., Penstock carries water under pressure from the water stored in a dam or reservoir to the turbine,, © The penstocks are made up of steel with reinforced concrete, which are designed to withstand high, Pressures. Penstocks are supported by anchors., o Sharp bends in penstocks are avoided in order to reduce the hydraulic losses., 7. Spillway:, © A spillway is provided to discharge the flood water and to keep the level of water below the, designed maximum level in the reservoir. Thus, a spillway saves the dam from damage during floods., 8. Water (Hydraulic) turbine:, © Hydraulic turbine converts hydraulic (water) energy into mechanical energy., © AHydraulic Turbine consists of:, ‘ (a) Wheel, called as “runner” provided with a number of curved vanes on its periphery., (b) A guiding apparatus to direct the flow of water at inlet of turbine in the specified direction., o A water turbine can be set horizontal or vertical. The factors considered are cost, type of turbine,, building space, plant layout etc., , °, , , , Scanned with CamScanner
