Project Report on water turbines

FABRICATION OF HYDEL POWER PLANT

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CHAPTER 1

SYNOPSIS Water turbines convert Mechanical Mechanical rotary energy into Electrical energy. A mechanical interface, consisting of a step-up gear, water Pump and a suitable coupling transmits the energy to an electrical generator. The output of this generator is connected to the Battery or system grid. The battery is connected to the inverter. The inverter is used to convert DC voltages to AC voltages. The load is drawn current from the inverter.

1. Generator 2. Main Mainss haft haft wit with h Lea Leafs fs 3. Gear Gear Whee Wheell Arr Arran ange geme ment nt

Water power ratings can be divided into three convenient grouping, small to 1kW, medium to 50 kW and large 200 kW to megawatt frame size.

Dept. of Mechanical Engg. ,MVJCE Page

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CHAPTER 2

INTRODUCTION Energy is the most important thing in this world. All living plants, animals (organisms) on this earth require energy to perform any type of work. The capacity to do a work is energy. The energy may require in smaller amount or in larger amount depending upon the nature of work to be performed. The different things from which we get the energy are called as Energy Sources. This is the simplest meaning of energy sources. There are two types of energy sources: 1 Conventional OR Non-Renewable Energy Energy Sources 2 Non-Conventional OR Renewable Energy Sources Sources

1 Conventional OR Non-Renewable Energy Energy Sources: The energy sources, which we are using from long time and which are in danger of exhausting, are called as Conventional OR Non-Renewable Energy Sources. They are not renewed by Nature and they are perishable, are going to get exhausted one day. e. g. coal, petroleum products, nuclear fuels etc.

2. Non-Conventional OR Renewable Energy Sources: These are the energy sources whose utilization technology is not yet fully developed. These are the sources, which can be recovered and reused. i. e. they can be used again and again to generate energy because of the renewal of their energy We are going to consider one of the ways of generation of energy from non-conventional energy namely hydroelectric energy. As name suggest, it is the energy obtained from water. The main principle used in this type is the kinetic energy of falling water is converted into electric energy using turbines. Hydro-electric Hydro-electric power is electricity produced by the flow of fresh water from lakes,

rivers, and streams. As water flows downwards thanks to gravity the kinetic energy it carries increases. This kinetic energy can be converted into mechanical energy - e.g. by turning a turbine - and from there into electrical energy. In the right location hydro-


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CHAPTER 2

INTRODUCTION Energy is the most important thing in this world. All living plants, animals (organisms) on this earth require energy to perform any type of work. The capacity to do a work is energy. The energy may require in smaller amount or in larger amount depending upon the nature of work to be performed. The different things from which we get the energy are called as Energy Sources. This is the simplest meaning of energy sources. There are two types of energy sources: 1 Conventional OR Non-Renewable Energy Energy Sources 2 Non-Conventional OR Renewable Energy Sources Sources

1 Conventional OR Non-Renewable Energy Energy Sources: The energy sources, which we are using from long time and which are in danger of exhausting, are called as Conventional OR Non-Renewable Energy Sources. They are not renewed by Nature and they are perishable, are going to get exhausted one day. e. g. coal, petroleum products, nuclear fuels etc.

2. Non-Conventional OR Renewable Energy Sources: These are the energy sources whose utilization technology is not yet fully developed. These are the sources, which can be recovered and reused. i. e. they can be used again and again to generate energy because of the renewal of their energy We are going to consider one of the ways of generation of energy from non-conventional energy namely hydroelectric energy. As name suggest, it is the energy obtained from water. The main principle used in this type is the kinetic energy of falling water is converted into electric energy using turbines. Hydro-electric Hydro-electric power is electricity produced by the flow of fresh water from lakes,

rivers, and streams. As water flows downwards thanks to gravity the kinetic energy it carries increases. This kinetic energy can be converted into mechanical energy - e.g. by turning a turbine - and from there into electrical energy. In the right location hydro-


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electric generation is far more cost effective than PV solar cells or wind turbines in terms of Watts generated per £ spent.

Fig 2.1

How much electrical energy can be generated by a hydroelectric turbine depends on the flow/quantity of water, and the height from which it has fallen (the head). The higher the head, and the larger the flow, the more electricity can be generated. Click here to view our article Calculation of Hydro Power to find out more. The image above shows the Rainbow Power 300 Watt Hydro Generator which costs around £1,300.

Hydropower Around the World


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Fig 2.2

By 2004, 6% of the world's electricity was hydro, some of that generated in enormous GigaWatt rated hydro power stations in Asia and Australia amongst other places including the World's largest hydropower plant at the Three Gorges Dam in China. However micro-hydro (a small localised hydro electic turbine) is also very useful for farmers and other people in remote locations. A part of a nearby river is diverted through a turbine to generate electricity and then the water is returned to the river at a lower point reducing the environmental impact. This is known as a run of river hydro power system. Where the flow of water is regular it is possible to set up a 240 AC hydro system which can be turned on whenever power is needed. Alternatively lower voltage DC electricity can be generated and stored in batteries for later use (via a 240V power inverter ).

2.1 HISTORY OF HYDEL POWER DEVELOPMENT The first recorded use of water power was a clock, built around 250 BC. Since that time, humans have used falling water to provide power for grain and saw mills, as well as a host of other applications. The first use of moving water to produce electricity


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was a waterwheel on the Fox River in Wisconsin in 1882, two years after Thomas Edison unveiled the incandescent light bulb. The first of many hydro electric power plants at Niagara Falls was completed shortly thereafter. Hydro power continued to play a major role in the expansion of electrical service early in this century, both in North America and around the world. Contemporary Hydro-electric power plants generate anywhere from a few kW, enough for a single residence, to thousands of MW, power enough to supply a large

city. Early hydro-electric power plants were much more reliable and efficient than the

fossil fuel fired plants of the day. This resulted in a proliferation of small to medium sized hydro-electric generating stations distributed wherever there was an adequate supply of moving water and a need for electricity. As electricity demand soared in the middle years of this century, and the efficiency of coal and oil fueled power plants increased, small hydro plants fell out of favor. Most new hydro-electric development was focused on huge "mega-projects". The majority of these power plants involved large dams which flooded vast areas of land to provide water storage and therefore a constant supply of electricity. In Recent years, the environmental impacts of such large hydro projects are being identified as a cause for concern. It is becoming increasingly difficult for developers to build new dams because of opposition from environmentalists and people living on the land to be flooded. This is shown by the opposition to projects such as Great Whale (James Bay II) in Quebec and the

Gabickovo-Nagymaros

project

on the Danube

River in

Czechoslovakia. Hydropower generation is an improvarient of primitive water wheel for grinding cereals. As hydro-electric power it emerged in USA in1882, followed by sweeden and Japan. In India, hydropower plant OF 130kw installed capacity was commissioned in 1897 at sidrapong at Dargiling in West Bengal and followed by 4.5MW plant at sivsamudram in Karnataka in 1902.during period between two world wars, a number of hydro power plants such as 48MW, at Jogindernagar(H.P.),17.4MW ganga power plant(U.P.), 38.75MWpykaraand 30MWmatter(Chnnai)were commissioned, from installed capacity of 1362MW,out of which hydropower was 508 MW in 1947,the pace of growth has been rapid in post independence era. The hydal install capacity by the end 2001

is

25,574MW,

out

of

total

capacity


5

of

102907MW.


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2.2 HYDROELECTRIC POWER Electricity produced from generators driven by water turbines that convert the energy in falling or fast-flowing water to mechanical energy. Water at a higher elevation flows downward through large pipes or tunnels (penstocks). The falling water rotates turbines, which drive the generators, which convert the turbines' mechanical energy into electricity. The advantages of hydroelectric power over such other sources as fossil fuels and nuclear fission are that it is continually renewable and produces no pollution. Norway, Sweden, Canada, and Switzerland rely heavily on hydroelectricity because they have industrialized areas close to mountainous regions with heavy rainfall. The U.S., Russia, China, India, and Brazil get a much smaller proportion of their electric power from hydroelectric generation. See also tidal power.Water is needed to run a hydroelectric generating unit. It’s held in a reservoir or lake behind the dam and the force of the water being released from the reservoir through the dam spins the blades of a turbine. The turbine is connected to the generator that produces electricity. After passing through the turbine, the water reenters

the

river

on

the

downstream

side

of

the

dam.

The capability to produce and deliver electricity for widespread consumption was one of the most important factors in the surge of American economic influence and wealth in the late nineteenth and early twentieth centuries. Hydroelectric power, among the first and simplest of the technologies that generated electricity, was initially developed using low dams of rock, timber, or granite block construction to collect water from rainfall and surface runoff into a reservoir. The water was funneled into a pipe (or pen-stock) and directed to a waterwheel (or turbine) where the force of the falling water on the turbine blades rotated the turbine and its main shaft. This shaft was connected to a generator, and the rotating generator produced electricity. One gallon (about 3.8 liters) of water falling 100 feet (about 30 meters) each second produced slightly more than 1,000 watts (or one kilowatt) of electricity, enough to power ten 100-watt light bulbs or a typical hairdryer. There are now three types of hydroelectric installations: storage, runof-river, and pumped-storage facilities. Storage facilities use a dam to capture water in a reservoir. This stored water is released from the reservoir through turbines at the rate required to meet changing electricity needs or other needs such as flood control,


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fish passage, irrigation, navigation, and recreation. Run-of-river facilities use only the natural flow of the river to operate the turbine. If the conditions are right, this type of project can be constructed without a dam or with a low diversion structure to direct water from the stream channel into a penstock. Pumped-storage facilities, an innovation of the 1950s, have specially designed turbines. These turbines have the ability to generate electricity the conventional way when water is delivered through penstocks to the turbines from a reservoir. They can also be reversed and used as pumps to lift water from the powerhouse back up into the reservoir where the water is stored for later use. During the daytime when electricity demand suddenly increases, the gates of the pumped-storage facility are opened and stored water is released from the reservoir to generate and quickly deliver electricity to meet the demand. At night when electricity demand is lowest and there is excess electricity available from coal or nuclear electricity generating facilities the turbines are reversed and pump water back into the reservoir. Operating in this manner, a pumped-storage facility improves the operating efficiency of all power plants within an electric system. Hydroelectric developments provide unique benefits not available with other electricity generating technologies. They do not contribute to air pollution, acid rain, or ozone depletion, and do not produce toxic wastes. As a part of normal operations many hydroelectric facilities also provide flood control, water supply for drinking and irrigation, and recreational opportunities such as fishing, swimming, water-skiing, picnicking, camping, rafting, boating, and sightseeing.

2.3 HYDRO ELECTRIC POWER PLANT Installations (e.g. Dams) to a large extent. Manufacturers have been quick enough to develop package designs for small units. These are also called as Small Scale Hydroelectric Power Plants. These facilities can supply in principle significant amounts of electricity for irrigation, or potable water pumping lighting or health or educational purpose. The total potential amount of such resources is poorly documented but is apt to be large. Up to 1972, hydro engineers concentrated on developing the larger sites, where the economy of scale enabled the production of energy at a cost low enough to compete thermal power etc. But the shortage of fuel, high cost of fuels needed for many


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of the other plants made the engineers to pay attention to the naturally occurring renewable sources which can be efficiently used as energy sources. Moreover, the remarkable advancement in the technology of development of turbines suitable for utilizing small falls and small discharges from RIVERS increased the chances of development of small hydral For many small hydro plants of less than 500 kW capacity, electronic load controllers have been developed to replace the governor. These controllers maintain a constant load on the turbine and hence constant flow, surplus power is diverted to a resistor and either wasted or used to heat water. The advantage of Hydro Power Plants operation in hilly areas and remote areas and the elimination of long transmission system, & lesser gestation periods have lent added attraction. It has little or no adverse environmental impact, effects on stream ecology. In India, the potential of small hydropower is estimated to be 5000 MW at present, while further investigations and surveys are expected to indicate a higher potential. Small Hydropower is covered in renewable programme. The alternate hydro-energy center at Roorki works on the development of solar hydropower system as well as Hybrid Hydro systems. If small hydropower stations are set up all over the country, decentralized availability of power will become possible. Many countries now have active small hydro development and rural electrification programmes, due to the several advantages offered by these plants. There is no formal definition of a small hydro plant but this may generally be taken as power station or plant having output up to 5000 kW. Some associate the concept of small hydro with low head say up to 15 m. This may not generally be true as there is no restriction on head for these power plants. Stations up to output 1000 kW are called micro and up to 5000 kW as mini power plants. Conceptually these power plants can be categorized into two types: 1) One utilizing small discharges but having high head 2) One utilizing large discharges but having comparatively smaller head. Hydro-electric power plants convert the kinetic energy contained in falling water into electricity. The energy in flowing water is ultimately derived from the sun, and is therefore constantly being renewed. Energy contained in sunlight evaporates water from the oceans and deposits it on land in the form of rain. Differences in land elevation result in rainfall runoff, and allow some of the original solar energy to be captured as hydro-electric power.


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Hydro power is currently the world's largest renewable source of electricity, accounting for 6% of worldwide energy supply or about 15% of the world's electricity. In Canada, hydroelectric power is abundant and supplies 60% of our electrical needs. Traditionally thought of as a cheap and clean source of electricity, most large hydro-electric schemes being planned today are coming up against a great deal of opposition from environmental groups and native people.

2.4 HYDRO-ELECTRIC POWER PLANTS Hydroelectric energy is produced by the force of falling water. The capacity to produce this energy is dependent on both the available flow and the height from which it falls. Building up behind a high dam, water accumulates potential energy. This is transformed into mechanical energy when the water rushes down the sluice and strikes the rotary blades of turbine. The turbine's rotation spins electromagnets which generate current in stationary coils of wire. Finally, the current is put through a transformer where the voltage is increased for long distance transmission over power lines. Hydro-electric power plants capture the energy released by water falling through a vertical distance, and transform this energy into useful electricity. In general, falling water is channeled through a turbine which converts the water's energy into mechanical power. The rotation of the water turbines is transferred to a generator which produces electricity. The amount of electricity which can be generated at a hydro-electric plant is dependant upon two factors. These factors are (1) the vertical distance through which the water falls, called the "head", and (2) the flow rate, measured as volume per unit time. The electricity produced is proportional to the product of the head and the rate of flow. The following is an equation which may be used to roughly determine the amount of electricity which can be generated by a potential hydro-electric power site: POWER (kW) = 5.9 x FLOW x HEAD In this equation, FLOW is measured in cubic meters per second and HEAD is measured in meters. Based on the facts presented above, hydroelectric power plants can generally be divided into two categories. "High head" power plants are the most common and generally utilize a dam to store water at an increased elevation. The use of a dam to impound water also provides the capability of storing water during rainy periods and releasing it during dry periods. This results in the consistent and reliable production of


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Electricity, able to meet demand. Heads for this type of power plant may be greater than 1000 m. Most large hydroelectric facilities are of the high head variety. High head plants with storage are very valuable to electric utilities because they can be quickly adjusted to meet the electrical demand on a distribution system.

2.5 HYDRO ELECTRIC POWER FOR THE NATION Although most energy in the United States is produced by fossil fuel and nuclear power plants, hydroelectricity is still important to the Nation, as about 10 percent of total power is produced by hydroelectric plants. Nowadays, huge power generators are placed inside dams. Water flowing through the dams spin turbine blades (made out of metal instead of leaves) which are connected to generators. Power is produced and is sent to homes and businesses. Producing electricity using hydroelectric power has some advantages over other power producing methods. Let's do a quick comparison: Reservoir construction is "drying up" Gosh, hydroelectric power sounds great -- so why don't we use it to produce all of our power? Mainly because you need lots of water and a lot of land where you can build a dam and reservoir, which all takes a LOT of money, time, and construction. In fact, most of the good spots to locate hydro plants have already been taken. In the early part of the century hydroelectric plants supplied a bit less than one-half of the nation's power, but the number is down to about 10 percent today. The trend for the future will probably be to build small-scale hydro plants that can generate electricity for a single community.

2.6 ENVIRONMENTAL IMPACTS Hydro-electric power plants have many environmental impacts, some of which are just beginning to be understood. These impacts, however, must be weighed against the environmental impacts of alternative sources of electricity. Until recently there was an almost universal belief that hydro power was a clean and environmentally safe method of producing electricity. Hydro-electric power plants do not emit any of the standard atmospheric pollutants such as carbon dioxide or sulfur dioxide given off by fossil fuel fired power plants. In this respect, hydro power is better than burning coal, oil or natural gas to produce electricity, as it does not contribute to global warming or acid


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rain. Similarly, hydro-electric power plants do not result in the risks of radioactive contamination associated with nuclear power plants. A few recent studies of large reservoirs created behind hydro dams have suggested that decaying vegetation, submerged by flooding, may give off quantities of greenhouse gases equivalent to those from other sources of electricity. If this turns out to be true, hydro-electric facilities such as the James Bay project in Quebec that flood large areas of land might be significant contributors to global warming. Run of the river hydro plants without dams and reservoirs would not be a source of these greenhouse gases. The most obvious impact of hydro-electric dams is the flooding of vast areas of land, much of it previously forested or used for agriculture. The size of reservoirs created can be extremely large. The La Grande project in the James Bay region of Quebec has already submerged over 10,000 square kilometers of land; and if future plans are carried out, the eventual area of flooding in northern Quebec will be larger than the country of Switzerland. Reservoirs can be used for ensuring adequate water supplies, providing irrigation, and recreation; but in several cases they have flooded the homelands of native peoples, whose way of life has then been destroyed. Many rare ecosystems are also threatened by hydro-electric development. Large dams and reservoirs can have other impacts on a watershed. Damming a river can alter the amount and quality of water in the river downstream of the dam, as well as preventing fish from migrating upstream to spawn. These impacts can be reduced by requiring minimum flows downstream of a dam, and by creating fish ladders which allow fish to move upstream past the dam. Silt, normally carried downstream to the lower reaches of a river, is trapped by a dam and deposited on the bed of the reservoir. This silt can slowly fill up a reservoir, decreasing the amount of water which can be stored and used for electrical generation. The river downstream of the dam is also deprived of silt which fertilizes the river's flood-plain during high water periods. Bacteria present in decaying vegetation can also change mercury, present in rocks underlying a reservoir, into a form which is soluble in water. The mercury accumulates in the bodies of fish and poses a health hazard to those who depend on these fish for food. The water quality of many reservoirs also poses a health hazard due to new forms of bacteria which grow in many of the hydro rivers. Therefore, run of the river type hydro plants generally have a smaller impact on the environment.


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2.7 DIFFERENT CLASSIFICATIONS OF HYDRAULIC POWER PLANTS 1. Depending upon Capacity to generate power: Size unit size Installation Micro upto 100 kW 100 kW Mini 101 to 1000 kW 2000 kW Small 1001 to 6000 kW 15000 kW

2. Depending on head: Ultra low head: Below3 meters, Low head : Less than 30 meters, Medium head: Between 30 to 75 meters,

High head : Above 75 meters,

2.8 SELECTION OF SITES FOR HYDRO POWER PLANT 1. Large quantity of water at a reasonable head should be available 2. The site should provide strong and high mountains on the two sides of the river reservoir with minimum gap for economical dam construction. 3. The rainfall should be sufficient to maintain desired water level in the reservoir throughout the year. 4. The catchments area for the reservoir to collect rainwater should be large. 5. There should not be any possibility of leakage of water in future. 6. The site should have firm rock for foundation.

2.9 BASIC COMPONENTS OF A HYDRO ELECTRIC POWER PLANT The basic and common components of a hydroelectric power plant are given below: a) Diversion and intake b) Desilting chamber c) Water conducting system d) Balancing reservoir e) Surge tank (if necessary)


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f) Penstock g) Power house: turbine, generator, protection and control equipment, dewatering, drainage system, auxiliary, power system, grounding, emergency and standby power system, lighting and ventilation Tail race channel .

Diversion structure: The diversion structure provided should be simple in construction as well as economical. It should involve minimum maintenance. Depending upon the type of river bed the diversion structure may be of two-type viz. Boulder weir and Trench type weir. It is usually constructed in re-enforced concrete or masonry.

Water conductor system: Water conducting system is the very important component of hydro-power plant. The type of water conductor system depends on the site conditions and the materials available. The design of the water conduction system should ensure minimum head loss, adequate velocity of flow so that silt does not settle down. The material of construction should be such that loss due to seepage is also minimized. The most commonly used channel section is trapezoidal.

Desalting tank : Desilting tank is provided usually in the initial reaches of water conductor to trap the suspended silt load and pebbles etc ; so as to minimize the erosion damages to the turbine runner. The size of silt particles to be trapped for medium head power stations is from 0.2 to 0.5 mm and for high head it is from 0.1 to 0.2 mm. The depth of tank may be kept between 1.5 to 4 m. The horizontal flow velocity should not exceed 0.4 to 0.6 m/s.

Layout of hydro power plants: The layout of hydro power plants envisages positioning of the various components of the plant to insure optimum use of available space for its efficient and convenient erection, operation and maintenance.

Power house The power is positioned at the toe of the concrete masonry dam where the suitable rock to lay foundation is available each turbine is fed by a separate penstock which is embedded inside the non-overflow section of the dam. The power house separated from the dam expansion joints. With a view to minimize the fluctuations in the


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tail water level. Especially due to ski jump trajectory, the power go use maybe located further downstream and fed through a tunnel branching into individual penstocks near the powerhouse. The powerhouse may be located at the underground, led through pressure shafts or pressure tunnels with surge tank. The power house may be located below the ski jump bucket itself. In the case of earth and rock fill dams, the power house is separated from the dam founded on suitable location and fed by penstock s generally taken out from a tunnel earlier used as diversion tunnel. Sometimes penstock may be laid in trench excavated below the dam buried in concrete.

TYPES OF POWERHOUSES: Surfaces power house: It is the best choice when sufficient area is available to accommodate the powerhouse within economical and convenient excavation. The there are three types of surface powerhouse depending on superstructure are outdoor, semi out door, indoor types

Semi-underground power house The surface with setting of turbines below the minimum tail water level may involve substantial excavation and then backfilling with concrete to facilitate construction of high retaining walls for protections against floods. In this type vertical shafts are driven in rock for housing part of draft tube, spiral casings turbines and generators.

Submersible powerhouse: In this type of power plant which is incorporated in the body of spillway beneath the crest. The head water elevation is incorporated in the body of spillway beneath the crest. The head water elevation is maintained with the help of vertical lift crest gates. It has advantages of economy because separate powerhouse structure is avoided in this arrangement.

2.10 HYDRO-ELECTRIC POWER: HOW IT WORKS So just how do we get electricity from water? Actually, hydroelectric and coal-fired power plants produce electricity in a similar way. In both cases a power source is used to turn a propeller-like piece called a turbine, which then turns a metal shaft in an electric generator which is the motor that produces electricity. A coal-fired power plant uses steam to turn the turbine blades; whereas a hydroelectric plant uses falling water to turn the turbine.


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FRANCIS TURBINE The theory is to build a dam on a large river that has a large drop in elevation (there are not many hydroelectric plants in Kansas or Florida). The dam stores lots of water behind it in the reservoir. Near the bottom of the dam wall there is the water intake. Gravity causes it to fall through the penstock inside the dam. At the end of the penstock there is a turbine propeller, which is turned by the moving water. The shaft from the turbine goes up into the generator, which produces the power. Power lines are connected to the generator that carry electricity to your home and mine. The water continues past the propeller through the tailrace into the river past the dam. By the way, it is not a good idea to be playing in the water right below a dam when water is released. The Francis turbine is a reaction turbine, which means that the working fluid changes pressure as it moves through the turbine, giving up its energy. A casement is needed to contain the water flow. The turbine is located between the high-pressure water source and the low-pressure water exit, usually at the base of a dam. The inlet is spiral shaped. Guide vanes direct the water tangentially to the turbine wheel, known as a runner . This radial flow acts on the runner's vanes, causing the runner to spin. The guide vanes (or wicket gate) may be adjustable to allow efficient turbine operation for a range of water flow conditions. As the water moves through the runner, its spinning radius decreases, further acting on the runner. For an analogy, imagine swinging a ball on a string around in a circle; if the string is pulled short, the ball spins faster due to the conservation of angular momentum. This property, in addition to the water's pressure, helps Francis and other inward-flow turbines harness water energy efficiently.


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Fig 2.1

IMPULSE TURBINES: THE PELTON WHEEL The impulse turbine is very easy to understand. A nozzle transforms water under a high head into a powerful jet. The momentum of this jet is destroyed by striking the runner, which absorbs the resulting force. If the velocity of the water leaving the runner is nearly zero, all of the kinetic energy of the jet has been transformed into mechanical energy, so the efficiency is high. A practical impulse turbine was invented by Lester A. Pelton (1829-1908) in California around 1870. There were high-pressure jets there used in placer mining, and a primitive turbine called the hurdy-gurdy, a mere rotating platform with vanes, had been used since the '60's, driven by such jets. Pelton also invented the split bucket, now universally used, in 1880. Pelton is a trade name for the products of the company he originated, but the term is now used generically for all similar impulse turbines. The water flows along the tangent to the path of the runner. Nozzles direct forceful streams of water against a series of spoon-shaped buckets mounted around the edge of a wheel. As water flows into the bucket, the direction of the water velocity changes to follow the contour of the bucket. When the water-jet contacts the bucket, the water exerts pressure on the bucket and the water is decelerated as it does a "u-turn" and flows out the other side of the bucket at low velocity. In the process, the water's momentum is transferred to the turbine. This "impulse” does work on the turbine. For maximum power and efficiency, the turbine system is designed such that the water-jet velocity is twice the


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velocity of the bucket. A very small percentage of the water's original kinetic energy will still remain in the water; however, this allows the bucket to be emptied at the same rate it is filled, (see conservation of mass), thus allowing the water flow to continue uninterrupted. Often two buckets are mounted side-by-side, thus splitting the water jet in half (see photo). This balances the side-load forces on the wheel, and helps to ensure smooth, efficient momentum transfer of the fluid jet to the turbine wheel. Because water and most liquids are nearly incompressible, almost all of the available energy is extracted in the first stage of the hydraulic turbine. Therefore, Pelton wheels have only one turbine stage, unlike gas turbines that operate with compressible fluid

Fig. 2.2

REACTION

TURBINES:

THE

LAWN

SPRINKLER

By contrast with the impulse turbine, reaction turbines are difficult to understand and analyze, especially the ones usually met with in practice. The modest lawn sprinkler comes to our aid, since it is both a reaction turbine, and easy to understand. It will be our introduction to reaction turbines. In the impulse turbine, the pressure change occurred in the nozzle, where pressure head was converted into kinetic energy. There was no pressure change in the runner, which had the sole duty of turning momentum change into torque. In the reaction turbine, the pressure change occurs in the runner itself at the


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same time that the force is exerted. The force still comes from rate of change of momentum, but not as obviously as in the impulse turbine. Underground sprinklers function through means of basic electronic and hydraulic technology. This valve and all of the sprinklers that will be activated by this valve are known as a zone. Upon activation, the solenoid, which sits on top of the valve is magnetized lifting a small stainless steel plunger in its center. By doing this, the activated (or raised) plunger allows air to escape from the top of a rubber diaphragm located in the center of the valve. Water that has been charged and waiting on the bottom of this same diaphragm now has the higher pressure and lifts the diaphragm. This pressurized water is then allowed to escape down stream of the valve through a series of pipes, usually made of PVC (higher pressure commercial systems) or polyethylene pipe (for typically lower pressure residential systems). At the end of these pipes and flush to ground level (typically) are pre measured and spaced out sprinklers. These sprinklers can be fixed spray heads that have a set pattern and generally spray between 1.5-2m (7–15 ft.), full rotating sprinklers that can spray a broken stream of water from 6-12m (20–40 ft.), or small drip emitters that release a slow, steady drip of water on more delicate plants such as

flowers

and

shrubs.

use

of

indegenous

materials

also

recommended..

The duty of the lawn sprinkler is to spread water; its energy output as a turbine serves only to move the sprinkler head. It is a descendant of Hero's aeolipile, the rotating globe with two bent jets that was quite a sensation in ancient times, though this worked with steam, not water. The lawn sprinkler seems directly descended from Rev. Robert Barker's proposed mill of 1740. He used two jets at right angles to the radius. A later improvement fed water from below to balance the weight of the runner and reduce friction. Barker's mills only appeared as models, and were never commercially offered. The flow of water in a lawn sprinkler is radially outward. Water under pressure is introduced at the centre, and jets of water that can cover the area necessary issue from the ends of the arms at zero gauge pressure. The pressure decrease occurs in the sprinkler arms. Though the water is projected at an angle to the radius, the water from an operating sprinkler moves almost along a radius. If you have such a sprinkler, by all means observe it in action. The jets do not impinge on a runner; in fact, they are leaving the runner, so their momentum is not converted into force as in the impulse turbine. The force on the runner must act in reaction to the creation of the momentum instead, which is, of course, the origin of the name of the reaction turbine.


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2.11 TOTAL ANNUAL COST OF HYDRO POWER PROJECT Total annual cost of hydro power project consists of three elements: 1. Fixed charges it includes fixed charges on plant interest taxes insurances depreciation and obsolescence

2. Operation and maintenance cost It includes operating cost, fuel cost, supervisory, labor maintenance, repair and miscellaneous expenses .the annual operation and maintenance cost is roughly proportional to the capacity of plant and the number of unit installed. The annual maintenance cost is usually taken as 1.5% of capital cost.

3. Transmission cost It covers the cost of transmission facilities to connect the power generated to the system load."Low head" hydroelectric plants are power plants which generally utilize heads of only a few meters or less. Power plants of this type may utilize a low dam or weir to channel water, or no dam and simply use the "run of the river". Run of the river generating stations cannot store water, thus their electric output varies with seasonal flows of water in a river. A large volume of water must pass through a low head hydro plant's turbines in order to produce a useful amount of power. Hydro-electric facilities with a capacity of less than about 25 MW (1 MW = 1,000,000 Watts) are generally referred to as "small hydro", although hydro-electric technology is basically the same regardless of generating capacity. "Pumped Storage" is another form of hydro-electric power. Pumped storage facilities use excess electrical system capacity, generally available at night, to pump water from one reservoir to another reservoir at a higher elevation. During periods of Peak electrical demand, water from the higher reservoir is released through turbines to the lower reservoir, and electricity is produced (Figure 2). Although pumped storage sites are not net producers of electricity - it actually takes more electricity to pump the water up than is recovered when it is released - they are a valuable addition to electricity supply systems. Their value is in their ability to store electricity for use at a later time when peak demands are occurring. Storage is even more valuable if intermittent sources of electricity such as solar or wind are hooked into a system.


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BULB-TYPE GENERATORS GE has a strong background in building large slow-speed horizontal synchronous machines of this type. In such applications, our experience focuses on air-gap stability, distortion control, unbalanced magnetic pull, ventilation, frame stiffness and seal design.

CONVENTIONAL GENERATORS Designed for all types of vertical axis applications, conventional generators are installed in locations having a variety of head and flow conditions .

STRAFLO (RIM-TYPE) GENERATORS These types of generators are designed for straight-flow turbine system applications to harness tidal flow effectively for the production of electric power as well as for low head applications.

MOTORS FOR PUMPED STORAGE Many utilities lower system costs by adding pumped storage capacity. In addition to supplying low cost peaking capacity, pumped storage provides spinning reserve to the system. GE has supplied more than 50 units with a total capacity of over 7,400,000 kVA (7,000,000 kW).

2.12 FUTURE DIRECTIONS FOR THE HYDROELECTRIC INDUSTRY The hydroelectric industry has been termed "mature" by some who charge that the technical and operational aspects of the industry have changed little in the past 60 years. Recent research initiatives counter this label by establishing new concepts for design and operation that show promise for the industry. A multi-year research project is presently testing new turbine designs and will recommend a final turbine blade configuration that will allow safe passage of more than 98 percent of the fish that are directed through the turbine. The DOE also recently identified more than 30 million kilowatts of untapped hydroelectric capacity that could be constructed with minimal environmental effects at existing dams that presently have no hydroelectric generating facilities, at existing hydroelectric projects with unused potential, and even at a number of sites without dams. Follow-up studies will assess the economic issues associated with this untapped hydroelectric resource. In addition, studies to estimate the hydroelectric potential of undeveloped, small capacity, dispersed sites that could supply electricity to adjacent areas without connecting to a regional electric transmission distribution system


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are proceeding. Preliminary results from these efforts have improved the visibility of hydroelectric power and provide indications that the hydroelectric power industry will be vibrant

and

important

to

the

country

throughout

the

next

century.

The theoretical size of the worldwide hydro power is about four times greater than that which has been exploited at this time. The actual amount of electricity which will ever be generated by hydro power will be much less than the theoretical potential. This is due to the environmental concerns outlined above, and economic constraints. Much of the remaining hydro potential in the world exists in the developing countries of Africa and Asia. Harnessing this resource would require billions of dollars, because hydro-electric facilities generally have very high construction costs. In the past, the World Bank has spent billions of foreign aid dollars on huge hydro-electric projects in the third world. Opposition to hydro power from environmentalists and native people, as well as new environmental assessments at the World Bank will restrict the amount of money spent on hydro-electric power construction in the developing countries of the world. In North-America and Europe, a large percentage of hydro power potential has already been developed. Public opposition to large hydro schemes will probably result in very little new development of big dams and reservoirs. Small scale and low head hydro capacity will probably increase in the future as research on low head turbines, and standardized turbine production, lowers the costs of hydro-electric power at sites with Companies have to dig up the Earth or drill wells to get the coal, oil, and gasor nuclear

power

plants

there

are

waste-disposal

problems

New computerized control systems and improved turbines may allow more electricity to be generated from existing facilities in the future. As well, many small hydro electric sites were abandoned in the 1950's and 60's when the price of oil and coal was very low, and their environmental impacts unrealized. Increased fuel prices in the future could result in these facilities being refurbished.

2.13 CASE STUDY EXAMPLE KOYNA DAM, KOYNA NAGAR . Koyna Dam is one of the largest dams in Maharashtra, India. It is located in Koyna Nagar, nestled in the Western Ghats on the state highway between Chiplun and


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Karad, Maharashtra. The dam supplies water to western Maharashtra as well as cheap hydroelectric power to the neighbouring areas with a capacity of 1,920 MW. The Koyna project is actually composed of four dams, with the Koyna dam having having the largest catchment area. The catchment area dams the Koyna River and forms a huge lake — the Shivsagar Lake whose length is 50 kilometres. Completed in 1963, it is one of the largest civil engineering projects commissioned after Indian independence. The Koyna electricity project is run by the Maharashtra State Electricity Board. Most of the generators are located in excavated caves a kilometre deep, inside the heart of the surrounding hills. The dam is blamed for the spate of earthquakes in the recent past. In 1967 a devastating earthquake almost razed the dam, with the dam developing major cracks. Geologists are still uncertain if the Koyna Dam is responsible for the spate in seismic activity. Koyna Dam is one of the largest damsinMaharashtra,India. It is located in Koyna Nagar, nestled in the Western Ghats on the state highway between Chiplun and Karad,Maharashtra. The dam supplies water to western Maharashtra as well as cheap Hydro electric power to the neighbouring areas with a capacity of 1,920 MW. The Koyna project is actually composed of four dams, with the Koyna dam having having the largest catchment area. The catchment area dams the Koyna River and forms a huge lake — the Shivsagar Lake whose length is 50 kilometres. Completed in 1963, it is one of the largest civil engineering projects commissioned after Indian independence. The Koyna electricity project is run by theMaharashtra State Electricity Board. Most of the generators are located in excavated cavesa kilometre deep, inside the heart of the surrounding hills.The dam is blamed for the spate of earthquake in the recent past. In 1967 a devastating earthquake almost razed the dam, with the dam developing major cracks. Geologists are still uncertain if the Koyna Dam is responsible for the spate in seismic activity.

Statistics • Storage: o Gross storage : 98.78 TMC o Live: 93.65 TMC o Dead: 5.125 TMC • Length: 1807.22 m


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• Height: 85.35 m

• Year of completion : 1963 The Koyna Dam in Maharashtra The resovoir behind the dam is 50 km in length.

Gravitational potential energy is stored in the water above the dam. Because of the great height of the water, it will arrive at the turbines at high pressure, which means that we can extract a great deal of energy from it. The water then flows away downriver as normal. In mountainous countries such as Switzerland and New Zealand, hydro-electric power provides more than half of the country's energy needs. An alternative is to build the station next to a fast-flowing river. However with this arrangement the flow of the water cannot be controlled, and water cannot be stored for later use. Hydro-electric power stations can produce a great deal of power very cheaply. When it was first built, the huge "Hoover Dam", on the Colorado river, supplied much of the electricity for the city of Las Vegas; however now Las Vegas has grown so much, the city gets most of its energy from other sources.There's a good explanation of how hydro power works at Although there are many suitable sites around the world, hydro-electric hydro-electric dams are very expensive to build. However, once the station is built, the water comes free of charge, and there is no waste or pollution. 1962 - 1963 Height of dam: 103 meters Water storage: 2,797.400 km³ Volume of dam: 1,555.000 m³ Width of dam : 808 m Slope at water side : 24:1 Length of 60 km

In a major technological breakthrough, the engineers of Koyna hydroelectric project today successfully performed the `lake tapping' operations at Shivaji Sagar reservoir of the dam. This operation or `lake tapping' using Norwegian technology will pave the way for the commissioning of the 1,000 MW stage four of the Koyna hydroelectric project, which would take total generation capacity to 1,920 MW by this year end.


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Enthusiasm reigned on the banks of Shivaji Sagar reservoir, as people from neighbouring villages flocked the lake to witness the `lake tapping', the first of its kind in Asia. Standing on the hilly terrain of the Koyna backwater, people were all ears to the announcements made by Shrikant Huddar, chief engineer of the Koyna Hydel project. And as Huddar instructed his subordinates to switch on the Konsbergs underwater cameras, the countdown for the million dollar blast had begun. Beginning from 10, Huddar launched his countdown and just after he had announcedzero, within a fraction of a second after Chief Minister Narayan Rane had switched knobs activating the blastings, hundreds of people felt waves of tremors passing under their feet. Suddenly, a mushroom flower-like cloud of water erupted from Shivaji Sagar reservoir, and ripples after ripples hit the banks. Soon after the ripples hit the banks, villagers standing on the banks lifted the water from the reservoir and gently applied it to their foreheads. No one could hear the sound of the blasts, but they had certainly felt it deep inside their hearts. Certainly it was a moment to cherish. Planned for 1000 MW power generation, the fourth stage of Koyna hydro electric project, envisages that the water will be tapped by piercing the Koyna reservoir, following which it will be carried through a 4.25 km-long head race tunnel into the underground power house. Speaking on the occasion after the blasts had been conducted, ministers Eknath Khadase,Anna Dange, Harshvardhan Patil, Deputy Chief Minister Gopinath Munde and Chief Minister Narayan Rane were all praise for the State irrigation department. While Irrigation Minister Khadse said such blasts could be replicated in future to generate more power, Rural Development Minister Anna Dange actually coined a couplet describing the event.Munde, who also holds the energy portfolio, expressed his gratitude to irrigation department for inviting him to witness the `lake tapping'. He also said the `event' was a major leap towards the State Government's dream to be selfsufficient in power generation. At present there is a shortage of nearly 1000-1500 MW of power in the State. This difference will be reduced after the Koyna fourth stage starts generating 1000 MW power. Chief Minister was also all praise for the irrigation department and said this development would go a long way in providing excess power for the State. The Koyana dam is at Koynanagar in Patan tehsil of Satara district in theSahyadaris. Its


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Shivaji Sagar reservoir has a capacity of 2,797 million cubic metres of water. The Rs 1,300 crore stage-four project is a World Bank funded project having commenced in 1992.

2.14 MAN AND ENERGY Man has needed and used energy at an increasing rate for its sustenance and well being ever since he came on the earth a few million years ago. Primitive man required energy primarily in the form of food. animals, which he hunted.

He derived this by eating plants or

Subsequently he discovered fire and his energy needs

increased as he started to make use of wood and other bio mass to supply the energy needs for cooking as well as agriculture. He added a mew dimension to the use of energy by domesticating and training animals to work for him. With further demand for energy, man began to use the wind for sailing ships and for driving windmills, and the force of failing water to turn water wheels. Till this time, it would not be wrong to say that the sun was supplying all the energy needs of man either directly or indirectly and that man was using only renewable sources of energy.The industrial revolution, which began with the discovery of the steam engine (AD 1700), brought about great many changes. For the first time, man began to use a new source of energy, viz. coal, in large quantities. A little later, the internal combustion engine was invented (AD1870) and the other fossil fuels, oil and natural combustion engine extensively. The fossil fuel era of using non-renewable sources had begun and energy was now available in a concentrated form. The invention of heat engines and then use of fossil fuels made energy portable and introduced the much needed flexibility in mans movement.For the first time, man could get the power of a machine where he required it and was not restricted to a specific site like a fast-running stream for running a water wheel or a windy hill for operating a windmill. This flexibility was enhanced with the discovery of electricity the development of central power generating stations using either fossil fuels or waterpower. A new source of energy-nuclear energy-came on the scene after the Second World War The first large nuclear power station was commissioned about 40 years ago, and already, nuclear energy is providing a small but significant amount of the energy requirements of many countries. Thus today, every country draws its energy needs from a


25


variety of sources.

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We can broadly categorize these sources as commercial and

noncommercial. The commercial sources include the fossil fuels (coal, oil and natural gas), hydroelectric power and nuclear power, while the non-commercial sources include wood, animal wastes, geothermal energy and agricultural wastes. In an industrialized country like USA, most of the energy requirements are meant from commercial sources, while in an industrially less developed country like India, the use of commercial and noncommercial sources is about equal. In the past few years, it has become obvious that fossil fuel resources are fast depleting and that the fossil fuel era is gradually coming to an end. This is particularly true for oil and natural gas. It will be use full there fore to first examine the rates of consumption of the different sources of energy and to give some indication of the reserves available this study will be done for the world as a whole and then for India in particular with the help of these figures it will be possible to form estimates of the time periods for which the existing source will be available. The need for alternative energy options will thus be established and these options will then be briefly described. Before passing on to these topics, it is worth noting that while man’s largescale use of commercial energy has led to a better quality of life it has also created many problems. Perhaps the most serious of these is the harmful effect on the environment. The combustion of the fossil fuel has caused serious air pollution problems in many areas because of the localized release of large amounts of harmful gases into the atmosphere. It has also resulted in the phenomenon of global warning, which is now a matter of great concern. Similarly the releases of large amounts of waste heat from power plants have caused thermal pollution in lakes and rivers leading to the destruction of many forms of plants and animals life.In the case of nuclear power plants there is also concern over the possibility of radio activity being released into the atmosphere in the event of an accident and over the long term problems of disposal of radioactive wastes from these plants. The gravity of most of these environmental problems had not really been foreseen. Now however, as man embarks on the search for alternative sources of energy, it is clear that the would do well to keep the environmental in mind.


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CHAPTER 3

COMPONENTS AND DESCRIPTION 3.1 PHYSICAL SETUP Water Pump Battery Inverter D.C Generator Lighting Load

3.1.1

WATER PUMP:-

The single phase induction motor is coupled with the vacuum pump impeller with suitable arrangement. It is found to drive the roller shaft which fixed on the end of the frame structure. The free end of the shaft in the motor a large pulley is found around which the belt runs. The other specification about the motor is discussed in design part of the machine.

3.1.2

BATTERIES

3.1.2.1 INTRODUCTION: In isolated systems away from the grid, batteries are used for storage of excess solar energy converted into electrical energy. The only exceptions are isolated sunshine load such as irrigation pumps or drinking water supplies for storage.In fact for small units with output less than one kilowatt.

Batteries seem to be the only technically and

economically available storage means. Since both the photo-voltaic system and batteries are high in capital costs. It is necessary that the overall system be optimized with respect


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to available energy and local demand pattern. To be economically attractive the storage of solar electricity requires a battery with a particular combination of properties:

(1)

Low cost

(2)

Long life

(3)

High reliability

(4)

High overall efficiency

(5)

Low discharge

(6)

Minimum maintenance (A)

Ampere hour efficiency

(B)

Watt hour efficiency

We use lead acid battery for storing the electrical energy from the solar panel for lighting the street and so about the lead acid cells are explained below.

3.1.2.2 LEAD-ACID WET CELL :

Where high values of load current are necessary, the lead-acid cell is the type most commonly used. The electrolyte is a dilute solution of sulfuric acid (H ₂SO₄). In the application of battery power to start the engine in an auto mobile, for example, the load current to the starter motor is typically 200 to 400A. One cell has a nominal output of 2.1V, but lead-acid cells are often used in a series combination of three for a 6-V battery and six for a 12-V battery. A battery is a device that converts chemical energy directly to electrical energy.It consists of a number of voltaic cells; each voltaic cell consists of two half-cells connected in series by a conductive electrolyte containing anions and cations. One half-cell includes electrolyte and the electrode to which anions (negatively charged ions) migrate, i.e., the anode or negative electrode; the other half-cell includes electrolyte and the electrode to which cations (positively charged ions) migrate, i.e., the cathode or positive electrode. In the redox reaction that powers the battery, cations are reduced (electrons are added) at the cathode, while anions are oxidized (electrons are removed) at the anode.The electrodes do not touch each other but are electrically connected by the electrolyte. Some


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cells use two half-cells with different electrolytes. A separator between half-cells allows ions to flow, but prevents mixing of the electrolytes. Each half-cell has an electromotive force (or emf), determined by its ability to drive electric current from the interior to the exterior of the cell. The net emf of the cell is the difference between the emfs of its half-cells, as first recognized by Volta. Therefore, if the electrodes have emfs

and

, then the net emf is

; in other words, the net

emf is the difference between the reduction potentials of the half-reactions. The electrical driving force or

across the terminals of a cell is known as the

terminal voltage (difference) and is measured in volts. The terminal voltage of a cell that is neither charging nor discharging is called the open-circuit voltage and equals the emf of the cell. Because of internal resistance, the terminal voltage of a cell that is discharging is smaller in magnitude than the open-circuit voltage and the terminal voltage of a cell that is charging exceeds the open-circuit voltage. An ideal cell has negligible internal resistance, so it would maintain a constant terminal voltage of

until exhausted, then

dropping to zero. If such a cell maintained 1.5 volts and stored a charge of one coulomb then on complete discharge it would perform 1.5 joule of work. In actual cells, the internal resistance increases under discharge, and the open circuit voltage also decreases under discharge. If the voltage and resistance are plotted against time, the resulting graphs typically are a curve; the shape of the curve varies according to the chemistry and internal arrangement employed. As stated above, the voltage developed across a cell's terminals depends on the energy release of the chemical reactions of its electrodes and electrolyte. Alkaline and zinc– carbon cells have different chemistries but approximately the same emf of 1.5 volts; likewise NiCd and NiMH cells have different chemistries, but approximately the same emf of 1.2 volts. On the other hand the high electrochemical potential changes in the reactions of lithium compounds give lithium cells emfs of 3 volts or more. The lead acid cell type is a secondary cell or storage cell, which can be recharged. The charge and discharge cycle can be repeated many times to restore the output voltage, as long as the cell is in good physical condition. However, heat with excessive charge and discharge currents shortends the useful life to about 3 to 5 years for an automobile


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battery. Of the different types of secondary cells, the lead-acid type has the highest output voltage, which allows fewer cells for a specified battery voltage.

3.1.2.3 CONSTRUCTION: Inside a lead-acid battery, the positive and negative electrodes consist of a group of plates welded to a connecting strap.

The plates are immersed in the electrolyte,

consisting of 8 parts of water to 3 parts of concentrated sulfuric acid. Each plate is a grid or framework, made of a lead-antimony alloy.

This construction enables the active

material, which is lead oxide, to be pasted into the grid. In manufacture of the cell, a forming charge produces the positive and negative electrodes. In the forming process, the active material in the positive plate is changed to lead peroxide (pbo ₂). The negative electrode is spongy lead (pb). The construction parts of battery are shown in figure.


30


Fig 3.1


31

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3.1.2.4 CHEMICAL ACTION:

Sulfuric acid is a combination of hydrogen and sulfate ions.

When the cell

discharges, lead peroxide from the positive electrode combines with hydrogen ions to form water and with sulfate ions to form lead sulfate. Combining lead on the negative plate with sulfate ions also produces he sulfate. There fore, the net result of discharge is to produce more water, which dilutes the electrolyte, and to form lead sulfate on the plates. As the discharge continues, the sulfate fills the pores of the grids, retarding circulation of acid in the active material. Lead sulfate is the powder often seen on the outside terminals of old batteries.

When the combination of weak electrolyte and

sulfating on the plate lowers the output of the battery, charging is necessary. On charge, the external D.C. source reverses the current in the battery. The reversed direction of ions flows in the electrolyte result in a reversal of the chemical reactions. Now the lead sulfates on the positive plate reactive with the water and sulfate ions to produce lead peroxide and sulfuric acid. This action re-forms the positive plates and makes the electrolyte stronger by adding sulfuric acid.

At the same time, charging

enables the lead sulfate on the negative plate to react with hydrogen ions; this also forms sulfuric acid while reforming lead on the negative plate to react with hydrogen ions; this also forms currents can restore the cell to full output, with lead peroxide on the positive plates, spongy lead on the negative plate, and the required concentration of sulfuric acid in the electrolyte.

The chemical equation for the lead-acid cell is

charge Pb + pbO₂ + 2H₂SO₄

2pbSO₄ + 2H₂O

Discharge

On discharge, the pb and pbo ₂ combine with the SO ₄ ions at the left side of the equation to form lead sulfate (pbSO₄) and water (H₂O) at the right side of the equation. One battery consists of 6 cells, each have an output voltage of 2.1V, which are connected Dept. of Mechanical

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in series to get an voltage of 12V and the same 12V battery is connected in series, to get an 24 V battery. They are placed in the water proof iron casing box.

3.1.2.5 CARING FOR LEAD-ACID BATTERIES:

Always use extreme caution when handling batteries and electrolyte.

Wear

gloves, goggles and old clothes. “Battery acid” will burn skin and eyes and destroy cotton and wool clothing.The quickest way of ruin lead-acid batteries is to discharge them deeply and leave them stand “dead” for an extended period of time.

When they

discharge, there is a chemical change in the positive plates of the battery.They change from lead oxide when charge out lead sulfate when discharged. If they remain in the lead Sulfate State for a few days, some part of the plate dose not returns to lead oxide when the battery is recharged. If the battery remains discharge longer, a greater amount of the positive plate will remain lead sulfate. The parts of the plates that become “sulfate” no longer store energy. Batteries that are deeply discharged, and then charged partially on a regular basis can fail in less then one year.Check your batteries on a regular basis to be sure they are getting charged. Use a hydrometer to check the specific gravity of your lead acid batteries. If batteries are cycled very deeply and then recharged quickly, the specific gravity reading will be lower than it should because the electrolyte at the top of the battery may not have mixed with the “charged” electr olyte. Check the electrolyte level in the wet-cell batteries at the least four times a year and top each cell of with distilled water. Do not add water to discharged batteries. Electrolyte is absorbed when batteries are very discharged.

If you add water at this time, and then recharge the battery,

electrolyte will overflow and make a mess.Keep the top of your batteries clean and check that cables are tight. Do not tighten or remove cables while charging or discharging. Any spark around batteries can cause a hydrogen explosion inside, and ruin one of the cells, and you.On charge, with reverse current through the electrolyte, the chemical action is reversed. Then the pb ions from the lead sulfate on the right side of the equation re-form the lead and lead peroxide electrodes. Also the SO₄ ions combine with H₂ ions from the water to produce more sulfuric acid at the left side of the equation. Lead–acid batteries lose the ability to accept a charge when discharged for too long due to sulfation, the crystallization of lead sulfate. They generate electricity through a double

Dept. of Mechanical Engg. ,MVJCE

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sulfate chemical reaction. Lead and lead dioxide, the active materials on the battery's plates, react with sulfuric acid in the electrolyte to form lead sulfate. The lead sulfate first forms in a finely divided, amorphous state, and easily reverts to lead, lead dioxide and sulfuric acid when the battery recharges. As batteries cycle through numerous discharges and charges, some lead sulfate is not recombined into electrolyte and slowly converts to a stable crystalline form that no longer dissolves on recharging. Thus, not all the lead is returned to the battery plates, and the amount of usable active material necessary for electricity generation declines over time. Sulfation occurs in all lead–acid batteries during normal operation. It impedes recharging; sulfate deposits ultimately expand, cracking the plates and destroying the battery. Eventually so much of the battery plate area is unable to supply current that the battery capacity is greatly reduced. In addition, the sulfate portion (of the lead sulfate) is not returned to the electrolyte as sulfuric acid. The large crystals physically block the electrolyte from entering the pores of the plates. Sulfation can be avoided if the battery is fully recharged immediately after a discharge cycle. A white coating on the plates may be visible (in batteries with clear cases, or after dismantling the battery). Batteries that are sulfated show a high internal resistance and can deliver only a small fraction of normal discharge current. Sulfation also affects the charging cycle, resulting in longer charging times, less efficient and incomplete charging, and higher battery temperatures. The process can often be at least partially reversed by a desulfation technique called pulse conditioning, in which short but powerful current surges are repeatedly sent through the damaged battery. Over time, this procedure tends to break down and dissolve the sulfate crystals, restoring some capacity. Desulfation is the process of reversing the sulfation of a lead-acid battery. Desulfation is achieved by high current pulses produced between the terminals of the battery. This technique, also called pulse conditioning , breaks down the sulfate crystals that are formed on the battery plates. Short high current pulses tend to work best. Electronic circuits are used to regulate the pulses of different widths and frequency of high current pulses. These can also be used to automate the process since it takes a long period of time to desulfate a


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battery fully. Battery chargers designed for desulfating lead-acid batteries are commercially available. A battery will be unrecoverable if the active material has been lost from the plates, or if the plates are bent due to over temperature or over charging. Batteries which have sat unused for long periods of time can be prime candidates for desulfation. A long period of self-discharge allows the sulfate crystals to form and become very large. Some typical cases where lead acid batteries are not used frequently enough are planes, boats (esp sail boats), old cars, and home power systems with battery banks that are under utilized. Some charging techniques can aid in prevention such as equalization charging and cycles through discharging and charging regularly. It is recommended to follow battery manufacturer instructions for proper charging. SLI batteries (starting, lighting, ignition; i.e. car batteries) have less deterioration because they are used more frequently vs deep cycle batteries. Deep cycle batteries tend to require more desulfation, can suffer from overcharging, and can be in a very large bank which leads to unequal charging and discharging

3.1.2.6 CURRENT RATINGS: Lead-acid batteries are generally rated in terms of how much discharge currents they can supply for a specified period of time; the output voltage must be maintained above a minimum level, which is 1.5 to 1.8V per cell. A common rating is ampere-hours (A.h.) based on a specific discharge time, which is often 8h.

Typical values for

automobile batteries are 100 to 300 A.h. As an example, a 200 A.h battery can supply a load current of 200/8 or 25A, used on 8h discharge. The battery can supply less current for a longer time or more current for a shorter time. Automobile batteries may be rated for “cold cranking power”, which is related to the job of starting the engine. A typical rating is 450A for 30s at a temperature of 0 degree F. Note that the ampere-hour unit specifies coulombs of charge. For instance, 200 A.h. corresponds to 200A*3600s (1h=3600s). the equals 720,000 A.S, or coulombs. One ampere-second is equal to one coulomb.

Then the charge equals 720,000 or

7.2*10^5ºC. To put this much charge back into the battery would require 20 hours with a charging current of 10A.The ratings for lead-acid batteries are given for a temperature


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range of 77 to 80ºF. Higher temperature increase the chemical reaction, but operation above 110ºF shortens the battery life. Low temperatures reduce the current capacity and voltage output. The amperehour capacity is reduced approximately 0.75% for each decreases of 1º F below normal temperature rating. At 0ºF the available output is only 60 % of the ampere-hour battery rating. In cold weather, therefore, it is very important to have an automobile battery unto full charge. In addition, the electrolyte freezes more easily when diluted by water in the discharged condition.

3.1.2.7 SPECIFIC GRAVITY: Measuring the specific gravity of the electrolyte generally checks the state of discharge for a lead-acid cell. Specific gravity is a ratio comparing the weight of a substance with the weight of a substance with the weight of water.

For instance,

concentrated sulfuric acid is 1.835 times as heavy as water for the same volume. Therefore, its specific gravity equals 1.835. The specific gravity of water is 1, since it is the reference.In a fully charged automotive cell, mixture of sulfuric acid and water results in a specific gravity of 1.280 at room temperatures of 70 to 80ºF. as the cell discharges, more water is formed, lowering the specific gravity. When it is down to about 1.150, the cell is completely discharged. Specific-gravity readings are taken with a battery hydrometer, such as one in figure (7). Note that the calibrated float with the specific gravity marks will rest higher in an electrolyte of higher specific gravity. convenience.

The decimal point is often omitted for

For example, the value of 1.220 in figure (7) is simply read “twelve

twenty”. A hydrometer reading of 1260 to 1280 indicates full charge, approximately 12.50 are half charge, and 1150 to 1200 indicates complete discharge. The importance of the specific gravity can be seen from the fact that the open-circuit voltage of the lead-acid cell is approximately equal to V

=

Specific gravity + 0.84For the specific gravity of 1.280,

the voltage is 1.280 = 0.84 = 2.12V, as an example. These values are for a fully charged battery.

3.1.2.8 CHARGING THE LEAD-ACID BATERY: The requirements are illustrated in figure. An external D.C. voltage source is necessary to produce current in one direction. Also, the charging voltage must be more Dept. of Mechanical

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than the battery e.m.f. Approximately 2.5 per cell are enough to over the cell e.m.f. so that the charging voltage can produce current opposite to the direction of discharge current.Note that the reversal of current is obtained just by connecting the battery VB and charging source VG with + to + and –to-, as shown in figure. The charging current is reversed because the battery effectively becomes a load resistance for VG when it higher than VB. In this example, the net voltage available to produce charging currents is 1512=3V.A commercial charger for automobile batteries is essentially a D.C. power supply, rectifying input from the AC power line to provide D.C. output for charging batteries.Float charging refers to a method in which the charger and the battery are always connected to each other for supplying current to the load. In figure the charger provides current for the load and the current necessary to keep the battery fully charged. The battery here is an auxiliary source for D.C. power.It may be of interest to note that an automobile battery is in a floating-charge circuit. The battery charger is an AC generator or alternator with rectifier diodes, driver by a belt from the engine. When you start the car, the battery supplies the cranking power. Once the engine is running, the alternator charges he battery. It is not necessary for the car to be moving. A voltage regulator is used in this system to maintain the output at approximately 13 to 15 V.The constant voltage of 24V comes from the solar panel controlled by the charge controller so for storing this energy we need a 24V battery so two 12V battery are connected in series.It is a good idea to do an equalizing charge when some cells show a variation of 0.05 specific gravity from each other. This is a long steady overcharge, bringing the battery to a gassing or bubbling state. Do not equalize sealed or gel type batteries.With proper care, lead-acid batteries will have a long service life and work very well in almost any power system. Unfortunately, with poor treatment lead-acid battery life will be very short.

3.1.3 INVERTER 3.1.3.1 INTRODUCTION: The process of converting D.C. into A.C. is known as INVERSION. In other words, we may define it as the reverse process of rectification.

The device, which

performs this process, is known as an INVERTOR. Inversion is, by no means, a recent process. In olden days gas-filled tubes and vacuum tubes were used to develop inverters. Thyratron inverter is popularly used as a large power device. Vacuum tube inverters were generally used for high-frequency applications. Some of the main disadvantages of the tube of as well as the mercury pool type inverters are: Dept. Mechanical Engg. ,MVJCE Page

37


1

They are very costly

2

They are very big in size and heavy in weight

3

They have very poor efficiency

4

The voltage drop across these devices is very high

5

They are less accurate

6

They are very slow in response, etc.

201 2

The basic principle of an inverter can be explained with the help of a simple circuit, as shown in figure. If switch S is connected alternately to position 1 and 2 at a rapid speed and if S is not kept closed to any of the two positions (1 and 2) for too long, and then an alternating voltage will appear across the primary winding. This can be explained by the direction of the current flow in the primary winding.

Although the voltage applied is D.C. in nature, the direction of current flow in the primary winding when S is connected to position 1 is from top to bottom whereas when S is connected at position 2, the current flows from bottom to top. This change in the direction of current flow in the primary winding gives rise to an alternating voltage in it. The frequencies of this alternating voltage will depend on how rapidly the switch (S) positions are interchanged. This alternating voltage in the primary winding will induce an alternating emf in the secondary winding, which will act as the A.C. output.With the development of semi-conductor devices, a lot of improvements to took place in the design of inverter circuits. Transistor being a fast-switching device was used as a switch for developing low and medium power inverters LAMP

STEAM

P.M.D.C. GENERATOR

BATTERY

INVERTOR

Fig 3.2


38


IN 4007

201 2 CIRCUIT DIAGRAM

IN 4007

9V-0-9V CHARGER

POLARITY PROTECTOR

100μF

CHARGING

50V

INDICATOR LED

+

-

ON/OFF SWITCH

12 V / 7.5 A.H

BATTERY 220Ω

IN 4007

100µF/50V

A.C MAINS

220Ω

RF 100µF/25V

CHOKE

0.1µF

120Ω

DISCHARGE

INDICATOR INVERTER BC 547

10k

TRANSFORMER

2N3055 POWER O/P

100µF/25V

CUM OSCILATOR

40 W

4.7 µF

560Ω

TUBE LIGHT


39


3.1.3.2

201 2

WORKING PRINCIPLE:-

3.1.3.2.1 CHARGING CIRCUIT The step down transformer is used to reduce the supply voltages in to 9-0-9V. This signal is rectified by the rectifier unit with the help of diodes. The Capacitor is used to filter the rectified signal and this signal is given to the battery input supply.

3.1.3.2.2 INVERTING CIRCUIT: The inverter circuit is activated when the switch is in on condition. The discharge indication is given with the help of discharge LED. The variable resister is used to varying the intensity of the tube light. The capacitors and transistors are used to amplifier cum oscillator circuit. This will produce the a.c signal and this signal is given to the inverter transformer. The inverter output is given to the load.

3.1.4

PERMANENT MAGNET D.C. GENERATOR:

3.1.4.1Voltage Production


3.1.3.2

201 2

WORKING PRINCIPLE:-

3.1.3.2.1 CHARGING CIRCUIT The step down transformer is used to reduce the supply voltages in to 9-0-9V. This signal is rectified by the rectifier unit with the help of diodes. The Capacitor is used to filter the rectified signal and this signal is given to the battery input supply.

3.1.3.2.2 INVERTING CIRCUIT: The inverter circuit is activated when the switch is in on condition. The discharge indication is given with the help of discharge LED. The variable resister is used to varying the intensity of the tube light. The capacitors and transistors are used to amplifier cum oscillator circuit. This will produce the a.c signal and this signal is given to the inverter transformer. The inverter output is given to the load.

3.1.4

PERMANENT MAGNET D.C. GENERATOR:

3.1.4.1Voltage Production DC Circuits, that there are three conditions necessary to induce a voltage into a conductor.

1 A magnetic field 2 A conductor 3 Relative motion between the two. A DC generator provides these three conditions to produce a DC voltage output.

3.1.4.2 Theory of Operation A basic DC generator has four basic parts: (1) A magnetic field; (2) A single conductor, or loop; (3) A commutator; and (4) Brushes The magnetic field may be supplied by either a permanent magnet or an electromagnet. For now, we will use a permanent magnet to describe a basic DC generator.


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Fig 3.3

Basic Operation of a DC Generator A single conductor, shaped in the form of a loop, is positioned between the magnetic poles. As long as the loop is stationary, the magnetic field has no effect (no relative motion). If we rotate the loop, the loop cuts through the magnetic field, and an EMF (voltage) is induced into the loop.When we have relative motion between a magnetic field and a conductor in that magnetic field, and the direction of rotation is such that the conductor cuts the lines of flux, an EMF is induced into the conductor. The magnitude of the induced EMF depends on the field strength and the rate at which the flux lines are cut.The stronger the field or the more flux lines cut for a given period of time, the larger the induced EMF.

Eg = K F N

where Eg = generated voltage K = fixed constant F = magnetic flux strength

N = speed in RPM The direction of the induced current flow can be determined using the "left-hand rule" for generators. This rule states that if you point the index finger of your left hand in the direction of the magnetic field (from North to South) and point the thumb in the direction of motion of the conductor, the middle finger will point in the direction of current flow.For example, the conductor closest to the N pole is traveling upward across the field; therefore, the current flow is to the right, lower corner. Applying the left-hand


41


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rule to both sides of the loop will show that current flows in a counter-clockwise direction in the loop.

3.1.4.3

DC GENERATOR CONSTRUCTION

Output Voltage-vs-Load Current for Shunt-Wound DC Generator the shuntwound generator, running at a constant speed under varying load conditions, has a much more stable voltage output than does a series-wound generator. Some change in output voltage does take place. This change is caused by the fact that, as the load current increases, the voltage drop (I R) across the armature coil increases, causing output voltage to decrease.As a result, the current through the field decreases, reducing the magnetic field and causing voltage to decrease even more. If load current is much higher than the design of the generator, the drop in output voltage is severe. For load current within the design range of the generator, the drop in output voltage is minimal. Early motor vehicles until about the 1960s tended to use DC generators with electromechanical regulators. These have now been replaced by alternators with built-in rectifier circuits, which are less costly and lighter for equivalent output. Moreover, the power output of a DC generator is proportional to rotational speed, whereas the power output of an alternator is independent of rotational speed. As a result, the charging output of an alternator at engine idle speed can be much greater than that of a DC generator. Automotive alternators power the electrical systems on the vehicle and recharge the battery after starting. Rated output will typically be in the range 50-100 A at 12 V, depending on the designed electrical load within the vehicle. Some cars now have electrically powered steering assistance and air conditioning, which places a high load on the electrical system. Large commercial vehicles are more likely to use 24 V to give sufficient power at the starter motor to turn over a large diesel engine. Vehicle alternators do not use permanent magnets and are typically only 50-60% efficient over a wide speed range.

3.1.5 LIGHTING LOAD: 3.1.5.1 FLUORESCENT TUBES: 3.1.5.1.1 INTRODUCTION: Dept. of Mechanical Engg. ,MVJCE Page

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This type of lamps is a low-pressure mercury vapor discharge lamp. Fluorescent lighting has a great advantage over other light source in many applications. It is possible to achieve quite high lighting intensities without excessive temperature rises.

The

efficiency of fluorescent lamp is about 40 lumens per watt, about three times the efficiency of an equivalent tungsten lamp. The average life of a fluorescent lamp is about 4,000 working hours.

3.1.5.1.2

CONSTRUCTION:

The fluorescent tube consists of a glass tube and 0.6 meter, 1.2 meters and 1.5 meters in length. The inside surface of the tube is coated with a thin layer of fluorescent material in the form of a powder.Various fluorescent materials give different color light. By mixing the various powders light of any desired color including daylight can be obtained.The glass tube of the fluorescent lamp is provided at both ends with bipin caps and oxide coated tungsten filaments. The tube contains organ gas with a small quantity of mercury under low pressure. Even with organ gas the discharge will not start at ordinary main voltage. A choke and a starter switch are therefore incorporated in the circuit of the tube lamp to give a momentary high voltage across the tube to start the discharge. The choke is connected in series with the tube the starter is connected across tube.

The circuit is suddenly opened at the starter, the flux around the choke collapse causing a kick of about 1000V. This voltage is applied across the two electrodes and sufficient to start the discharge of the tube. During the steady operation of this lamp the voltage across the tube drops to about 150 volts. This voltage is sufficient to maintain the discharge of the tube. During the steady operation of this lamp, the voltage across the tube drops to about 150 volts. This voltage is sufficient to maintain the discharge. The choke in series with the tube now acts as a stabilizer. A capacitor is connected across the circuit it improve the power factor.


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CHAPTER-4

WORKING PRINCIPLE The block diagram of hydro power plant is consisting of a water tank, 12 voltage batteries, an inverter and a florescent lamp. As we studied from the generator gives a D.C. output of 12V this D.C. output is not always constant there is some variation in this D.C. output this cannot be given to the battery storage it may weaken the life of the battery. So in order to get constant D.C. output and also to avoid the reverse flow of current to the panel in the case of no load a charge controller have been used this help

us to allow only the constant voltage of 12V D.C. to the battery and also it act as an blocking diode and protect the motor principle.By this way the battery gets charged then this D.C. storage is given to an inverter this inverter inverts 12V D.C. to input in to AC output, step upped in to 230V.The 230V AC supply is given to the supply to the lamp. The lamp used for street lighting is 230V, 50 Hz, single phase supply.


44


Fig 4.1


45

201 2

FABRICATION OF HYDEL POWER PLANT 5.1 ADVANTAGES

201 2

CHAPTER-5

ADVANTAGES AND DISADVANTAGES 1

Power is produced by the simply the water pumping system

2

This is a Non-conventional system

3

Battery is used to store the generated power

4

Low cost power generation system

5

Once a dam is constructed, electricity can be produced at a constant rate.

6

If electricity is not needed, the sluice gates can be shut, stopping electricity generation. The water can be saved for use another time when electricity demand is high.

7

Dams are designed to last many decades and so can contribute to the generation of electricity for many years / decades.

8

The lake that forms behind the dam can be used for water sports and leisure / pleasure activities. Often large dams become tourist attractions in their own right.

9

The lake's water can be used for irrigation purposes.

10

The build up of water in the lake means that energy can be stored until needed, when the water is released to produce electricity.

11

When in use, electricity produced by dam systems do not produce green house gases. They do not pollute the atmosphere.

5.1 DISADVANTAGES

1

Only applicable for the particular place.

2

Initial cost of this arrangement is high.


46


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CHAPTER-6 3

Dams are extremely expensive to build and must be built to a very high standard.

4

The high cost of dam construction means that they must operate for many decades to become profitable. The flooding of large areas of land means that the natural environment is destroyed.

5

People living in villages and towns that are in the valley to be flooded, must move out. This means that they lose their farms and businesses. In some countries, people are forcibly removed so that hydro-power schemes can go ahead.

6

The building of large dams can cause serious geological damage. For example, the building of the Hoover Dam in the USA triggered a number of earth quakes and has depressed the earth’s surface at its location.

7

Although modern planning and design of dams is good, in the past old dams have been known to be breached (the dam gives under the weight of water in the lake). This has led to deaths and flooding.

8

Dams built blocking the progress of a river in one country usually means that the water supply from the same river in the following country is out of their control. This can lead to serious problems between neighbouring countries.

9

Building a large dam alters the natural water table level. For example, the building of the Aswan Dam in Egypt has altered the level of the water table. This is slowly leading to damage of many of its ancient monuments as salts and destructive minerals are deposited in the stone work from ‘rising damp’ caused by the changing water table level

APPLICATIONS Dept. of Mechanical Engg. ,MVJCE Page

47


6.1

201 2

Direct heat applications

Mechanical motion derived from water power can be used to drive heat pumps or to produce heat from the friction of solid materials, or by the churning of water or other fluids, or in other cases, by the use of centrifugal or other types of pumps in combination with restrictive orifices that produces heat from friction and turbulence when the working fluid flows through them. This heat may then be stored in materials having a high heat capacity, such as water, stones, eutectic salts, etc.,A home heating system that uses a water powered pump and a restrictive orifice to derive direct heat for a building, without first generating electricity also has been developed. In thermal power stations, mechanical power is produced by a heat engine that transforms thermal energy, often from combustion of a fuel, into rotational energy. Most thermal power stations produce steam, and these are sometimes called steam power stations. Not all thermal energy can be transformed into mechanical power, according to the second law of thermodynamics. Therefore, there is always heat lost to the environment. If this loss is employed as useful heat, for industrial processes or district heating, the power plant is referred to as a cogeneration power plant or CHP (combined heat-and-power) plant. In countries where district heating is common, there are dedicated heat plants called heat-only boiler stations. An important class 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 produced and is not directly a function of the fuel used. For the same steam conditions, coal, nuclear and gas 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). Besides use of reject heat for process or district heating, one way to improve overall efficiency of a power plant is to combine two different thermodynamic cycles. Most commonly, exhaust gases from a gas turbine are used to generate steam for a boiler and steam turbine. The combination of a "top" cycle and a "bottom" cycle produces higher overall efficiency than either cycle can attain alone


48


6.2

201 2

Electric Generation Applications: Water power can be used in centralized utility applications to drive synchronous

A.C. electrical generators. In such applications the energy is fed directly into power networks through voltage step-up transformers. This unit can be integrated with existing hydro electrical networks and used in a “water-saver” mode of operation. When the water is blowing, electrical an amount equal to the being can reduce generation at the hydroelectric plants in the network produced by this unit. Thus, the water turbines supply part of the network load that is ordinarily produced by the hydroelectric generators. Under these conditions some of the water that would have been used by the hydroelectric plant to supply the load is saved in the reservoir and made available for later use when the water is not blowing. Hydroelectricity is the term referring to electricity generated by hydropower; the production of electrical power through the use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy, accounting for 16 percent of global electricity consumption, and 3,427 terawatt-hours of electricity production in 2010, which continues the rapid rate of increase experienced between 2003 and 2009. Hydropower is produced in 150 countries, with the Asia-Pacific region generating 32 percent of global hydropower in 2010. China is the largest hydroelectricity producer, with 721 terawatt-hours of production in 2010, representing around 17 percent of domestic electricity use. There are now three hydroelectricity plants larger than 10 GW: the Three Gorges Dam in China, Itaipu Dam in Brazil, and Guri Dam in Venezuela The cost of hydroelectricity is relatively low, making it a competitive source of renewable electricity. The average cost of electricity from a hydro plant larger than 10 megawatts is 3 to 5 U.S. cents per kilowatt-hour.Hydro is also a flexible source of electricity since plants can be ramped up and down very quickly to adapt to changing energy demands. However, damming interrupts the flow of rivers and can harm local ecosystems, and building large dams and reservoirs often involves displacing people and wildlife.Once a hydroelectric complex is constructed, the project produces no direct waste, and has a


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considerably lower output level of the greenhouse gas carbon dioxide (CO 2) than fossil fuel powered energy plants.

CHAPTER-7 Dept. of Mechanical Engg. ,MVJCE Page

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201 2

LIST OF MATERIALS

SL. NO. 1 2 3 4 5 6 7 8 9

NAME OF THE PARTS

MATERIAL

QUANTITY

Water Pump Tube Generator (D.C 12 V) Battery (12 V) Inverter Frame Stand Hose Collar Turbine blade Connecting Wire

Aluminium Plastic Aluminium Lead-acid Electronic PCB Mild Steel Brass Mild Steel Cu

1 1 1 1 5 meter 1 2 1 2 meter

CHAPTER-8

COST ESTIMATION 8.1

MATERIAL COST:


Page

51


SL.

NAME OF THE

NO. 1 2 3 4 5 6 7 8 9

PARTS

MATERIAL

AMOUNT (RS)

Water Pump Tube Generator (D.C 12 V) Battery (12 V) Inverter Frame Stand Hose Collar Turbine blade Connecting Wire

TOTAL

QUANTITY

201 2

Aluminium Plastic Aluminium Lead-acid Electronic PCB Mild Steel Brass Mild Steel Cu

1 1 1 1 5 meter 1 2 1 2 meter

=

1800.00 800.00 1560.00 2000.00 2500.00 1200.00 250.00 760.00 125.00

Rs. 10995.00

8.2 LABOUR COST

LATHE, DRILLING, WELDING, GRINDING, POWER HACKSAW, GAS CUTTING: Cost = Rs. 2500.00

8.3

OVERHEAD CHARGES


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201 2

The overhead charges are arrived by “Manufacturing cost”

Manufacturing Cost

=

Material Cost + Labour cost

= Rs (10995.00+2500.00) = Rs.13495.00

Overhead Charges

=

20% of the manufacturing cost

= Rs. 2699.00

TOTAL COST

Total cost

=

Material Cost + Labour cost + Overhead Charges

=Rs. 16194.00

Total cost for this project

= Rs. 16194.00

CHAPTER-9

CONCLUSION A strong multidiscipline team with a good engineering base is necessary for the Development and refinement of advanced computer programming, editing techniques, diagnostic algorithms for the dynamic exchange of informational different Dept. ofSoftware, Mechanical Engg. ,MVJCE Page

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201 2

levels of hierarchy. Simulation techniques are suitable for solving some of the problems. But a good quantitative model and a test set-up will help to understand the systems. This project work has provided us an excellent opportunity and experience, to use our limited knowledge. We gained a lot of practical knowledge regarding, planning, purchasing, assembling and machining while doing this project work. We feel that the project work is a good solution to bridge the gates between institution and industries. Hydropower is the cheapest way to generate electricity today. No other energy source, renewable or nonrenewable, can match it. Producing electricity from hydropower is cheap because, once a dam has been built and the equipment installed, the energy sourceflowing water-is free. Although Hydropower does present a few environmental problems the inherent technical, economic and environmental benefits of hydroelectric power make it an important contributor to the future world energy mix.We are proud that we have completed the work with the limited time successfully. The HYDRO POWER PLANT is working with satisfactory conditions. We are able to understand the difficulties in maintaining the tolerances and also quality. We have done to our ability and skill making maximum use of available facilities. In conclusion remarks of our project work, let us add a few more lines about our impression project work. Thus we have developed a “HYDRO POWER PLANT” which helps to know how to achieve low cost steam power plant model. By using more techniques, they can be modified and developed according to the applications. The scenario presented in this web quest may seem unrealistic, or even silly. However, the truth of the matter is that unless we start to look for alternative energy resources now, we may encounter such a situation in the future. Experts believe that we have about 50 years until we deplete our fossil fuel resources. Fifty years is a long time. Definitely long enough to develop a replacement energy source. However, unless more funding is devoted to developing these renewable resources we may find ourselves in the midst of such an energy crisis in the future. Furthermore, as individuals we need to realize that the energy that we often waste may not last forever. This is why we should ensure that it is not wasted. Instead, we should treat it more preciously. Doing little things such as turning off unnecessary lights, or walking/riding a bicycle whenever possible –instead of driving- can make a big difference. Our individual efforts can go a long way in delaying the imminent depletion of fossil fuels.


Page

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9.2 World hydroelectric capacityComparison with other methods of power generation Hydroelectricity eliminates the flue gas emissions from fossil fuel combustion, including pollutants such as sulfur dioxide, nitric oxide, carbon monoxide, dust, and mercury in the coal. Hydroelectricity also avoids the hazards of coal mining and the indirect health effects of coal emissions. Compared to nuclear power, hydroelectricity generates no nuclear waste, has none of the dangers associated with uranium mining, nor nuclear leaks. Unlike uranium, hydroelectricity is also a renewable energy source. Compared to wind farms, hydroelectricity power plants have a more predictable load factor. If the project has a storage reservoir, it can generate power when needed.

Hydroelectric plants can be easily regulated to follow

variations

in power

demand.Hydroelectricity eliminates the flue gas emissions from fossil fuel combustion, including pollutants such as sulfur dioxide, nitric oxide, carbon monoxide, dust, and mercury in the coal. Hydroelectricity also avoids the hazards of coal mining and the indirect health effects of coal emissions. Compared to nuclear power, hydroelectricity generates no nuclear waste has none of the dangers associated with uranium mining, nor nuclear leaks. Unlike uranium, hydroelectricity is also a renewable energy source. Compared to wind farms, hydroelectricity power plants have a more predictable load factor. If the project has a storage reservoir, it can generate power when needed. Hydroelectric plants can be easily regulated to follow variations in power demand.


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9.3 World hydroelectric capacity

Fig 9.1 The ranking of hydro-electric capacity is either by actual annual energy production or by installed capacity power rating. Hydro accounted for 16 percent of global electricity consumption, and 3,427 terawatt-hours of electricity production in 2010, which continues the rapid rate of increase experienced between 2003 and 2009. Hydropower is produced in 150 countries, with the Asia-Pacific region generated 32 percent of global hydropower in 2010. China is the largest hydroelectricity producer, with 721 terawatt-hours of production in 2010, representing around 17 percent of domestic electricity use. Brazil, Canada, New Zealand, Norway, Paraguay, Austria, Switzerland, and Venezuela have a majority of the internal electric energy production from hydroelectric power. Paraguay produces 100% of its electricity from hydroelectric dams, and exports 90% of its production to Brazil and to Argentina. Norway produces 98–99% of its electricity from hydroelectric sources. There are now three hydroelectric plants larger than 10 GW: the Three Gorges Dam in China, Itaipu Dam in Brazil, and Guri Dam in Venezuela. A hydro-electric plant rarely operates at its full power rating over a full year; the ratio between annual average power and installed capacity rating is the capacity factor. The installed capacity is the sum of all generator nameplate power ratings.


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Major projects under construction Name

Maximum Capacity

Country

Construction Scheduled started

completion

Comments

Construction once Xiluodu Dam

12,600 MW

Belo

11,181

MonteZDam

MW

China

December 26, 2005

2015

stopped due to lack of environmental impact study. Preliminary

Brazil

March, 2011 2015

construction underway. Multi-phase construction over a

Siang Upper HE 11,000 Project

MW

India

April, 2009

2024

period of 15 years. Construction was delayed due to dispute with China. Controversial 228 meter tall dam with

TaSang Dam

7,110 MW Burma

March, 2007 2022

capacity to produce 35,446 Ghw annually.

Xiangjiaba Dam 6,400 MW China Nuozhadu Dam 5,850 MW China

November 26, 2006 2006

2015 2017 To build this dam, 23 families and 129

Jinping 2 Hydropower

4,800 MW China

Station

January 30, 2007

local residents need 2014

to be moved. It works with Jinping 1 Hydropower Station as a group.

Diamer-Bhasha

4,500 MW Pakistan

Dam Jinping 3,600 MW China Dept.1of Mechanical

October 18,

2023

2011 November 11, 2014

Engg. ,MVJCE Page

57


Name

Maximum Capacity

Country

Hydropower


completion

201 2

Comments

2005

Station

Construction halted Jirau Dam

3,300 MW Brazil

2008

2012

in March 2011 due to worker riots.

Pubugou Dam

3,300 MW China

Goupitan Dam

3,000 MW China

Guanyinyan Dam

March 30, 2004 November 8, 2003

2010 2011 Construction of the

3,000 MW China

2008

2015

roads and spillway started.

Liangheko Dam 3,000 MW China Boguchan Dam 3,000 MW Russia Dagangshan 2,600 MW China Dam Sơn La Dam

2,400 MW Vietnam

Guandi Dam

2,400 MW China

Liyuan Dam

2,400 MW China

2009 1980 August 15, 2008 December 2, 2005 November 11, 2007 2008

2015 2013 2014 2012 2012

This power plant would be the last development in the Low Caroni Basin, Tocoma Dam Bolívar State

2,160 MW Venezuela 2004

2014

bringing the total to six power plants on the same river, including the 10,000MW Guri

Ludila Dam

2,100 MW China

2007

2015

Dam Construction halt due to lack of the environmental


58


Name

Shuangjiangkou

Maximum Capacity

Country

2,000 MW China

Dam Ahai Dam 2,000 MW China Lower Subansiri 2,000 MW India Dam


completion

Comments

assessment. The dam will be 312

December, 2007 July 27, 2006 2005

201 2

m high.

2012

FIGURES, GRAPHS AND MAPS


59



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BIBLIOGRAPHY


Page

61

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Project Report on water turbines

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