WELCOME

1. WELCOME EN 108: BASIC ELECTRICAL ENGG

2. ENERGY • Energy provides the power to progress • 93% of total power generated is consumed by North America &Europe while ½ of the world’s population lives in Asia. • In developed countries the main source of income is thru Industrial Activities where more power consumption is required.

3. Advantages of Electrical Energy • It is the most refined form of energy • Can be generated in large quantities at comparable cost with other types of energy • Conveniently transmitted over long distances • Can be utilized efficiently in a no. of processes requiring energy • Got max. flexibility ,sensitive and easy to control

4. features • Electrical energy is the back bone of industrial world • Comfort, convenience &safety of people all over the world depends on electrical power • Energy may be needed as heat , light, motive power or direct use in electrical processes • It may be needed in large or small amounts, continuously or intermittently, in various locations

5. Types of Energy Sources • Sold fuels • Liquid fuels • Natural gas • Hydro • nuclear

6. Main parts of a power system • Generating stations • TXN system • DXN system

7. Main parts of a power system Generating stations TXN system DXN system Methods of generation 1.Conventional methods Thermal Hydro Nuclear 2. Non conventional methods Solar, wind, tidal, Geothermal, Photovoltaic & fuel cells

8. Power plant economics • Pp is an assembly of equipments that produces & delivers electrical energy • Classification of pp 1.on the basis of fuel used (i)Steam pp (ii)diesel (iii)nuclear (iv)hydel (v)gas turbine 2.On the basis of nature of load (i)Base load plant (ii) peak load plant 3.On the basis of location (i)Central pp (ii)isolated pp 4.On the basis of service rendered (i)stationary (ii)locomotive

9. Requirement of pp eee • 1 . Economy of expenditure i.e. min. capital cost &op.and maintenance cost • Safety of plant & personal • Reliability • Efficiency • Ease of maintenance • Good working conditions • Min.TXN losses

10. Types of loads • Residential • Commercial • Industrial • Municipal • Irrigation etc

11. Main parts of a power system Generating stations TXN system DXN system Methods of generation 1.Conventional methods Thermal Hydro Nuclear 2. Non conventional methods Solar, wind, tidal, Geothermal, Photovoltaic & fuel cells

12. Thermal power stations • The heat of combustion of coal is utilised in a boiler which produces steam at suitable pressure sufficient to run a steam turbine & latter drives a generator G B T

13. Thermal power advantages disadvantages • Can be installed near load centres & hence less TXN loss &TXN cost • Not dependent on weather conditions • High initial cost &maintenance cost • High running cost • Pollution • Frequent faults • High cost of generation

14. Site selection for thermal pp • Proximity of load centers • Availability of rail tracks • Adequate supply of water • Availability of suitable land sufficient to meet future expansions • Means of ash disposal

17. Coal storage Chimney Air pre heater Economizer Generator Coal handling TURBINE Cooling tower BOILER and SUPER HEATER Ash handling Ash storage Condenser Cooling Water pump Feed pump L.P. Heater H.P. Heater Condensate Extraction pump

19. MAIN PARTS Boiler Soot blowers Coal storage Forced draft fan coalhandling equipment Chimney Steam turbine Dust extractor Condenser Governor Air heaters Ash storage&handling Boiler feed water pump Circulating water pump Economiser

20. Coal– from coal storage- pulverized in mills-fed to boiler & burnt • Boiler – The fuel is burnt here , the boiler consists of superheater,economiser,airheater,ash extractor & furnace for burning coal • Economizer –increases thermal efficiency by utilizing heat in the exhaust gases to be absorbed by feed water. • Air heater- used to increase the thermal efficiency by absorbing heat from exhaust gases by air used for combustion purpose. • Soot blowers-remove the ash adhering to water tubes • De aerator - extracts soluble gases from water. • Steam Turbine- turbine drives the electric generator using the high pressure steam from the boiler. • Condenser-steam after work is passed thru the condenser for condensation & the water is cooled with the help of Cooling towers. • Chimney-used for the disposal of flue gases • Governor- to control the speed & regulate the o/p of the turbines • Generator- ac generator for electric power generation

21. Working of thermal pp • Coal from coal storage is supplied to the furnace • Preheated water is supplied to the boiler thru water circuit where it is changed to steam at high pressure. • This steam is supplied to the steam turbine. Steam under pressure moves the blades of the turbine which in turn drives the alternator (ac generator) • Steam after work is passed thru the condenser for condensation. Water is cooled with the help of cooling towers. • Flue gases are passed thru the economizer &air heaterfor heat collection. • 20% of the coal contains ash. usually used method for ash disposal is the pumping s/m

22. ENVIRONMENTAL ISSUES IN COAL BASED POWER GENERATION • Air Pollution :- High particulate matter emission levels due to burning of inferior grade coal which leads to generation of large quantity of flyash • Emissions of SO2,NOx & Green house gas (CO2) are also matter of concern • Water Pollution :- Mainly caused by the effluent discharge from ash ponds, condenser cooling /cooling tower, and Boiler • blow down. • Noise Pollution :- High noise levels due to release of high pressure steam and running of fans and motors • Land Degradation :- About 100 million tonnes of fly ash is generated by use of coal for energy production. The disposal of such large quantity of fly ash has occupied thousands hectares of land which includes agricultural and forest land too.

23. furnace

25. condenser

26. Cooling tower

27. Wrong boiler fuel to air ratio • Water side boiler scale • Fireside boiler slagging • Turbine blade deposits • Poor turbine blade condition • Waterside steam condenser tube scale

28. Alternators The alternator is driven by a steam turbine. In power stations, powered by coal, oil or nuclear reactor huge alternators are used to generate electricity

29. Emission Estimates

30. the THANK YOU

32. Hydroelectric Power Background • Energy from hydroelectric power is renewable • It is powered by the water cycle • Converts forms of energy • Potential-kinetic-mechanical-electrical

35. Hydroelectric Power • Conversion from potential energy of • water to electric energy is at 80 – 90% • efficiency -Hydroelectric projects in the United States have rated capacities from 950 – 6480 MW • The use of Water Power is much • greater in some other countries. • Norway obtains 99% of its electricity • from water power. Nepal, Brazil, and • New Zealand are close seconds. Water generated - Hydroelectric Shasta Dam In California

36. Site selection for hydro electric pp • Availability of water • Transportation facility • Head of water • Storage facility • Cost & nature of site • Nature of site • Environmental factors • Topography of the area

37. Hydro Power Plant Working How HydroPower Plant works layout

38. HYDEL PP • Generation • Irrigation • Flood control FEATURES Running cost low Reliable Can be put off and on quickly Greater life No waste disposal problem Highly efficient over a considerable range of load Can be used as base & peak load plant

39. Essential parts • Reservoir-basic requirement.Water stored is used to run turbines to produce e’ power.It can be natural or artificial • Dam-structure built at a suitable location across the river whose primary function is to provide head of water. Economy & safety are the basic requirements .It should be capable of resisting the pressure of water & silt. • Trash rack- prevents the debris from getting entry into the intakes from dam or from forebay. It is made of steel bars and placed across the intake. Manual or mech. Cleaning is used. • Penstock – to convey water from reservoir to the power house .It is made of steel,RCC or wood. • Power house & equipments – It includes turbines,generators,governers ,gate valve, flow measuring equipment, transformers, switch board etc • Tail race- It is the waterway to lead the water discharged from the turbine to the river. • Draft tube – connects the turbine exit water to tail race. It is a metallic pipe or concrete tunnel

40. Surge tank- it is a storage reservoir fitted to the penstock at the point near to the turbine. It is provided to overcome the inertial forces in the supply pipe during fall of load & to act as reservoir of water during increase of load. Surge tank controls water when load on the turbine changes. Spillway – controls the water level of the dam . it prevents the overflow.

41. Thank you

42. NON CONVENTIONAL ENERGY SOURCES • Advantages Widely available Non polluting Well suited for decentralised use Not depleting in nature Minimum environmental problem

43. Solar energy • Greatest promise to mankind • Free,inexhaustible,nonpolluting and devoid of political control • Can eliminate most of the environmental problems associated with fossil fuels,nuclear,hydel etc

44. 5. Solar Energy: • The heat energy contained in the rays of sun is utilized to boil water and generate steam which can be used to drive prime movers to generate electrical energy. • Utilization of solar energy is of great importance to India since it lies in a temperature climate of the region of the world where sunlight is abundant • for a major part of the year.

47. Solar Two

48. Solar Water Heating • Advantages • Replacing or supplementing other water heating methods: natural gas, electricity • Disadvantages • More expensive in cooler climates

49. Wind energy