CHAPTER NUMBER

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INTRODUCTION OF POWER GENERATION

1.1 Electric Power Generation

Electricity generation is the process of converting non-electrical energy to electricity. For electric utilities, it is the first process in the delivery of electricity to consumers. The other processes, electric power transmission and electricity distribution, are normally car Periodic changes of water levels, and associated tidal currents, are due to

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the gravitational attired out by the electrical power industry .Electricity is most often generated at a power station by electromechanical generators.1.1.1 History:

Centralized power generation became possible when it was recognized that alternating current power lines can transport electricity at very low costs across great distances by taking advantage of the ability to raise and lower the voltage using power transformers.

Electricity has been generated at central stations since 1881. The first power plants were run on water power or coal, and today we rely mainly on coal, nuclear, natural gas, hydroelectric, and petroleum with a small amount from solar energy, tidal harnesses, wind generators, and geothermal sources.

1.1.2 Electricity Generation:A "generator" and "motor" is essentially the same thing: what you call it depends

on whether electricity is going into the unit or coming out of it.

A generator produces electricity. In a generator, something causes the shaft and

armature to spin. An electric current is generated, as shown in the picture (lightning bolt).

Lots of things can be used to make a shaft spin - a pinwheel, a crank, a bicycle, a

water wheel, a diesel engine, or even a jet engine. They're different sizes but it's the same

general idea. It doesn't matter what's used to spin the shaft - the electricity that's produced

is the same.

A motor uses electricity. In a motor, the electricity comes in through wires

attached to the positive (+) and negative (-) terminals. The electric current causes the

armature and shaft to spin. If there's just a little current and it's a small motor, it won't do

very much work (i.e. it can only spin a small fan). If it's a large motor and it's using a lot

of electricity, it can do a lot of work (i.e. spin a large fan very fast; lift a very heavy load;

or whatever the motor is being used for). Electric generators are essentially very large

quantities of copper wire spinning around inside very large magnets, at very high speeds.

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A commercial utility electric generator -- for example, a 180-megawatt generator

at the Hawaiian Electric Company's Kahe power plant on Oahu -- can be quite large. It is

20 feet in diameter, 50 feet long, and weighs over 50 tons. The copper coils (called the

"armature") spin at 3600 revolutions per minute. Although the principle is simple (copper

wire and magnets), it's not necessarily easy!

Steam turbine generators, gas turbine generators, diesel engine generators,

alternate energy systems (except photovoltaic), even nuclear power plants all operate on

the same principle - magnets plus copper wire plus motion equals electric current. The

electricity produced is the same, regardless of source.

So where all the different do fuels come in? It's all a question of how to get (and

keep) the system moving (i.e. how to keep the copper wire spinning around).

In a steam power plant, fuels (such as petroleum, coal, or biomass) are burned to heat water which turns into steam, which goes through a turbine, which spins...turning the copper wire (armature) inside the generator and generating an electric current.

A geothermal power plant is pretty much a steam power plant, since what comes

out of the earth is steam. Rainwater soaks into the ground and goes down, down,

down...far enough until it reaches a region which is really hot (in Hawaii, that's about

6000 feet). A well is drilled, the steam comes out, goes through a heat exchanger, and

spins a turbine... turning the copper wire (armature) inside the generator and generating

an electric current. By the time the steam has gone through the heat exchanger, it has

cooled off and become warm water. It is then re-injected into the ground.

In a gas turbine power plant, fuels are burned to create hot gases which go

through a turbine, which spins...turning the copper armature inside the generator and

generating an electric current.

In a nuclear power plant, nuclear reactions create heat to heat water, which turns

into steam, which goes through a turbine, which spins...turning the copper armature

inside the generator and generating an electric current.

In a wind turbine, the wind pushes against the turbine blades, causing the rotor to

spin...turning the copper armature inside the generator and generating an electric current.

In a hydroelectric turbine, flowing (or falling) water pushes against the turbine

blades, causing the rotor to spin...turning the copper armature inside the generator and

generating an electric current.

Consumers expect electricity to be available whenever they plug in an appliance,

turn a switch, or open a refrigerator. Satisfying these instantaneous demands requires an

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uninterrupted flow of electricity. In order to meet this requirement, utilities and non

utility electricity power producers operate several types of electric generating units,

powered by a wide range of fuel sources. These include fossil fuels (coal, natural gas, and

petroleum), uranium, and renewable fuels (water, geothermal, wind, and other renewable

energy sources).

Coal was the fuel used to generate the largest share (51.8 percent) of electricity in

2000 1,968 billion kilowatt hours (kWh). This is over one and a half times the annual

electricity consumption of all U.S. households (1,141 billion kWh). Natural gas was used

to generate 612 billion kWh (16.1 percent), and petroleum accounted for 109 billion kWh

(3 percent). Steam-electric generating units burn fossil fuels, such as coal, natural gas, and petroleum. The steam turns a turbine that produces electricity through an electrical generator. Natural gas and petroleum are also burned in gas turbine generators where the hot gases produced from combustion are used to turn the turbine, which, and in turn, spins the generator to produce electricity. Additionally, petroleum is burned in generating units with internal-combustion engines. The combustion occurs inside cylinders of the engine, which is connected to the shaft of the generator. The mechanical energy provided from the engine drives the generator to produce energy.

1.2 Methods of power generation:1) Gas power.2) Hydro power.3) Diesel power.4) Thermal power.5) Nuclear power.6) Solar energy.7) Wind power.8) Wave power.9) Tidal power.10) Biogas power.11) Geo thermal power.12) Coal gasification

1.2.1 Gas power generation:Natural gas is a major source of electricity generation through the use of gas

turbines and steam turbines. Particularly high efficiencies can be achieved through combining gas turbines with a steam turbine in combined cycle mode. Natural gas burns cleaner than other fossil fuels, such as oil and coal, and produces less carbon dioxide per unit energy released. For an equivalent amount of heat, burning natural gas produces about 30% less carbon dioxide than burning petroleum and about 45% less than burning coal. Combined cycle power generation using natural gas is thus the cleanest source of power available using fossil fuels, and this technology is widely used wherever gas can

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be obtained at a reasonable cost. Fuel cell technology may eventually provide cleaner options for converting natural gas into electricity, but as yet it is not price-competitive.

Natural gas is a mixture of combustible gases formed underground by the decomposition of organic materials in plant and animal. It is usually found in areas where oil is present, although there are several large underground reservoirs of natural gas where there is little or no oil. Natural gas is widely used for heating and cooking, as well as for a variety of industrial applications.

1.2.2 Hydro power:

Hydroelectricity is electricity generated by hydropower, i.e., the production of power through use of the gravitational force of falling or flowing water. It is the most widely used form of renewable energy. Once a hydroelectric complex is constructed, the project produces no direct waste, and has a considerably different output level of the greenhouse gas carbon dioxide (CO2) than fossil fuel powered energy plants. Worldwide, hydroelectricity supplied an estimated 715,000 MWe in 2005. This was approximately 19% of the world's electricity (up from 16% in 2003), and accounted for over 63% of electricity from renewable sources.

Some jurisdictions do not consider large hydro projects to be a sustainable energy source, due to the human, economic and environmental impacts of dam construction and maintenance.

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Most hydroelectric power comes from the potential energy of dammed water driving a water turbine and generator. In this case the energy extracted from the water depends on the volume and on the difference in height between the source and the water's outflow. This height difference is called the head. The amount of potential energy in water is proportional to the head. To obtain very high head, water for a hydraulic turbine may be run through a large pipe called a penstock.

Pumped storage hydroelectricity produces electricity to supply high peak demands by moving water between reservoirs at different elevations. At times of low electrical demand, excess generation capacity is used to pump water into the higher reservoir. When there is higher demand, water is released back into the lower reservoir through a turbine. Pumped storage schemes currently provide the only commercially important means of large-scale grid energy storage and improve the daily load factor of the generation system. Hydroelectric plants with no reservoir capacity are called run-of-the-river plants, since it is not then possible to store water. A tidal power plant makes use of the daily rise and fall of water due to tides; such sources are highly predictable, and if conditions permit construction of reservoirs, can also be dispatch able to generate power during high demand periods.

1.2.2.1 Advantages:

Once the dam is built, the energy is virtually free. No waste or pollution produced. Much more reliable than wind, solar or wave power. Water can be stored above the dam ready to cope with peaks in demand.

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Hydro-electric power stations can increase to full power very quickly, unlike other power stations.

Electricity can be generated constantly.

1.2.2.2 Disadvantages: The dams are very expensive to build.

However, many dams are also used for flood control or irrigation, so building costs can be shared.

Building a large dam will flood a very large area upstream, causing problems for animals that used to live there.

Finding a suitable site can be difficult - the impact on residents and the environment may be unacceptable.

Water quality and quantity downstream can be affected, which can have an impact on plant life.

1.2.3 Diesel power:A Diesel power station (also known as Stand-by power station) uses a diesel

engine as prime mover for the generation of electrical energy.

This power station is generally compact and thus can be located where it is actually required. This kind of power station can be used to produce limited amounts of electrical energy. In most countries these power stations are used as emergency supply stations.

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1.2.3.1 Operation:

The diesel burns inside the engine and the combustion process causes rotational mechanical energy that turns the engine shaft and drives the alternator. The alternator in turn, converts mechanical energy into electrical energy.

This type of electricity generating power station will probably be used a long time into the future, due to a need for reliable stand-by electrical source for emergency situations.

1.2.3.2 Advantages:

Simple design & layout of plant. Occupies less space & is compact.

Can be started quickly and picks up load in a short time.

Requires less water for cooling.

Thermal efficiency better that of Steam Power plant of same size.

Overall cost is cheaper than that of Steam Power plant of same size.

Requires no Operating staff.

No stand-by losses.

1.2.3.3 Disadvantages:

High running charges due to costly price of Diesel. Plant does not work efficiently under prolonged overload conditions.

Generates small amount of power.

Cost of lubrication very high.

Maintenance charges are generally high.

1.2.4 Thermal / Power Generation:

A thermal power station is a power plant in which the prime mover is steam driven. Water is heated, turns into steam and spins a steam turbine which drives an electrical generator. After it passes through the turbine, the steam is condensed in a condenser; this is known as a Ranking cycle. The greatest variation in the design of thermal power stations is due to the different fuel sources. Some prefer to use the term energy center because such facilities convert forms of heat energy into electrical energy.

Thermal power generation has a central role to play in supplying electric power, and we are striving for the development of power generation technology that is even more efficient. 1.2.4.1 Steam power generation (LNG-Fired Station):

Steam power plant facilities constitute a means of power generation that uses the expansion power of steam. Fuel is burned inside a boiler to heat water and generate

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steam. This steam is then used to drive turbines which in turn drive the power generators to make electricity. This steam is suitable for the use of thermal energy of relative low temperature (below 600°C).

1.2.4.1.1 Main parts of thermal power generation:

Fuel Tanks

Natural gas produced in such places as Malaysia, Brunei, Das Island, and Alaska is converted onsite to liquefied natural gas (LNG) with a temperature of -162°C and a volume that is 1/600th of the original gas, and transported in specially designed vessels. After the LNG has been stored in tanks with a double-walled construction like that used for a thermos flask, it is turned back into gas by a vaporizer and transferred to the boiler. One kilogram of LNG generates heat equivalent to some 13,000 kcal.

BoilersBoilers burn the fuel transferred from the tank and use the resulting heat to

convert water into steam. Inside the boilers are tens of thousands of water-carrying tubes.

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When combustion commences, the temperature inside the boilers rises to between 1,100 and 1,500°C, the water inside the tubes is turned into high-temperature and high-pressure steam, and the steam is transferred to the steam turbines.

Turbines

The steam rotates the turbine blades at a high speed of 3,000 rpm. This turns the power generator, which is directly connected to the turbines, and electricity is produced as a result. This electric power is then delivered along power transmission lines and through substations to the homes of customers. The steam is cooled by seawater in a condenser, restored to water, and then returned to the boiler for reuse. This cycle of water to steam to water is repeated over and over again.

1.2.4.2 Combined cycle (CC) Power Generation: Combined cycle power generation is a method of generating electric power that

combines gas turbine power generation with steam turbine power generation. By employing a 1,100°C class gas turbine in the high-temperature section and by effectively recycling the exhaust energy of this section in the steam system, the thermal efficiency can be boosted to 43%. Furthermore, several small-capacity individual units are combined to configure a large-capacity power generation facility, and startup and shutdown operations can be easily tailored to the fluctuation in demand.

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For this reason, by adjusting the number of operating units under middle and low outputs, the facility can be run at all times with the same high efficiency as with the rated outputs. This, together with other features, makes combined cycle power generation an excellent system in terms of mobility and thermal operating efficiency. TEPCO turned its attention to the above-mentioned benefits of combined cycle power generation at the early date of 1986 and introduced it to the Futtsu Thermal Power Station, where a combined total of 2,000 MW are generated by Group1 and Group 2.

1.2.4.3 Class of Combined Cycle Power Generation ACC (Advanced Combined Cycle):

With advanced combined cycle (ACC) power generation, the inlet gas temperature of the gas turbine is raised to 1,300°C, higher temperature and pressure levels are established as in the steam conditions in the steam turbines, and a reheating cycle is also employed to improve the thermal efficiency. These enhancements increase the thermal efficiency of ACC power generation to 50%.

Since TEPCO introduced this kind of ACC power generation facility to its Yokohama Thermal Power Stations in 1996, it has brought these facilities on-line in its Chiba Thermal Power Station, Futtsu Thermal Power Station Group 3, and Shinagawa Thermal Power Station.

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1.2.4.4 Class of Combined Cycle Power Generation MACC (More Advanced Combined Cycle):

This system is based on the ACC power generation system and achieves even higher efficiency and capacity by raising the inlet gas temperature of the gas turbine to even higher levels. By raising the temperature to 1,450°C through such technical innovations as the development of heat-resistant materials for the gas turbines and gas turbine steam cooling, the thermal efficiency has been improved to 53%.

In the future, this technology is destined to become the keystone of thermal power generation not only because of its ability to conserve fuel through the improvements in the thermal efficiency and its effect of reducing the amount of carbon dioxide discharged but also because the larger capacities take full advantage of the scale, which makes it possible to lower construction costs.

Future plans call for TEPCO to introduce the 1,450°C class of combined cycle power generation to its Kawasaki Thermal Power Station and Futtsu Thermal Power Station Group 4.

1.2.5 Nuclear power: A nuclear reactor is a device in which nuclear chain reactions are initiated,

controlled, and sustained at a steady rate, as opposed to a nuclear bomb, in which the chain reaction occurs in a fraction of a second and is uncontrolled causing an explosion.

The most significant use of nuclear reactors is as an energy source for the generation of electrical power (see Nuclear power) and for the power in some ships (see Nuclear marine propulsion). This is usually accomplished by methods that involve using heat from the nuclear reaction to power steam turbines.

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1.2.5.1 How it works:

In an induced nuclear fission event. A neutron is absorbed by the nucleus of a uranium-235 atom, which in turn splits into fast-moving lighter elements (fission products) and free neutrons.The physics of operating a nuclear reactor are explained in Nuclear reactor physics.

1.2.5.2 Electrical power generation:

The energy released in the fission process generates heat, some of which can be converted into usable energy. A common method of harnessing this thermal energy is to use it to boil water to produce pressurized steam which will then drive a steam turbine that generates electricity.

1.2.5.3 Advantages: Nuclear power costs about the same as coal, so it's not expensive to make. Does not produce smoke or carbon dioxide, so it does not contribute to the

greenhouse effect. Produces huge amounts of energy from small amounts of fuel.

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Produces small amounts of waste. Nuclear power is reliable.

1.2.5.4 Disadvantages: Although not much waste is produced, it is very, very dangerous.

It must be sealed up and buried for many thousands of years to allow the radioactivity to die away. For all that time it must be kept safe from earthquakes, flooding, terrorists and everything else. This is difficult.

Nuclear power is reliable, but a lot of money has to be spent on safety - if it does go wrong, a nuclear accident can be a major disaster. People are increasingly concerned about this - in the 1990's nuclear power was the fastest-growing source of power in much of the world. In 2005 it was the second slowest-growing.

1.2.6 Solar energy: Solar technology converts sunshine into useful thermal energy, and subsequently into electricity, by way of parabolic mirrors that concentrate the solar energy onto solar thermal receivers containing a heat transfer fluid. The heat transfer fluid is circulated and heated through the receivers, and the heat is released to a series of heat exchangers to generate super-heated steam. The steam powers a turbine/generator to produce electricity delivered to a utility’s electric grid. A central computerized tracking facility enables optimal absorption of the sun’s energy by automatically adjusting the alignment of the parabolic mirrors. From the moment the sun rises until it dips over the horizon, all of its rays are captured and converted into usable energy.

With a back-up of alternative fuels, a solar plant can operate beyond daylight hours.

1.2.6.1 How does Photovoltaic work?

1. al Connection can be net metering as illustrated, or gross metering.2. Low voltage DC electricity is generated by the solar array 3. The DC electricity is fed to the Inverter which changes it to 240V AC 4. Appliances in the house use solar electricity direct from the Inverter 5. Any excess electricity flows through a meter and is sold to the electricity grid at

the applicable 'Feed In' tariff

Electricity also flows back from the grid through the meter as per norm

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Solar cells convert sunlight into electricity and are made of semi-conducting materials such as silicone. When sunlight is absorbed, the solar energy knocks electrons loose from their atoms, and the electrons flow through the material producing low voltage electricity.

This process of converting light (photons) to electricity (volts) is called the PHOTOVOLTAIC effect.

When the thin silicone wafers, or cells, are wired together their combined electrical output is increased. So different sized panels are produced depending on the number of cells contained therein and they are commonly sized by their output of Watts.

Because PV panels are modular and can be connected together easily, they are often referred to as ‘solar modules’. Two types are commonly used, Mono-crystalline and Poly-crystalline. Mono-crystalline cells perform better in low light conditions.

A Photovoltaic system from All Solar Systems can provide some or all of your home’s electricity needs. We install 1 kilowatt 1.5 kilowatt up to 5 kilowatt systems.

Unlike the solar heat concentrators mentioned above, photovoltaic panels convert sunlight directly to electricity. Although sunlight is free and abundant, solar electricity is still usually more expensive to produce than large-scale mechanically generated power due to the cost of the panels. Low-efficiency silicon solar cells have been decreasing in cost and multifunction cells with close to 30% conversion efficiency are now

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commercially available. Over 40% efficiency has been demonstrated in experimental systems. Until recently, photovoltaics were most commonly used in remote sites where there is no access to a commercial power grid or as a supplemental electricity source for individual homes and businesses. Recent advances in manufacturing efficiency and photovoltaic technology, combined with subsidies driven by environmental concerns, have dramatically accelerated the deployment of solar panels. Installed capacity is growing by 40% per year led by increases in Germany, Japan, California and New Jersey.

1.2.6.2 Advantages:

Solar energy is free - it needs no fuel and produces no waste or pollution.

In sunny countries, solar power can be used where there is no easy way to get electricity to a remote place.

Handy for low-power uses such as solar powered garden lights and battery chargers, or for helping your home energy bills.

1.2.6.3 Disadvantages:

Doesn't work at night.

Very expensive to build solar power stations.Solar cells cost a great deal compared to the amount of electricity they'll produce in their lifetime.

Can be unreliable unless you're in a very sunny climate. In the United Kingdom, solar power isn't much use for high-power applications, as you need a large area of solar panels to get a decent amount of power. However, technology has now reached the point where it can make a big difference to your home fuel bills...

1.2.7 Wind power: Wind-powered turbines usually provide electrical generation in conjunction with other methods of producing power.1.2.7.1 How it works:

The Sun heats our atmosphere unevenly, so some patches become warmer than others.

These warm patches of air raise, other air blows in to replace them and we feel a wind blowing.

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We can use the energy in the wind by building a tall tower, with a large propeller on the top.

The wind blows the propeller round, which turns a generator to produce electricity.

We tend to build many of these towers together, to make a "wind farm" and produce more electricity.

The more towers, the more wind, and the larger the propellers, the more electricity we can make.

It's only worth building wind farms in places that have strong, steady winds, although boats and caravans increasingly have small wind generators to help keep their batteries charged.

The best places for wind farms are in coastal areas, at the tops of rounded hills, open plains and gaps in mountains - places where the wind is strong and reliable. Some are offshore.

To be worthwhile, you need an average wind speed of around 25 km/h. Most wind farms in the UK are in Cornwall or Wales.

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1.2.7.2 Advantages:

Wind is free, wind farms need no fuel.

Produces no waste or greenhouse gases. The land beneath can usually still be used for farming. Wind farms can be tourist attractions. A good method of supplying energy to remote areas.

1.2.7.3 Disadvantages:

The wind is not always predictable - some days have no wind.

Suitable areas for wind farms are often near the coast, where land is expensive. Some people feel that covering the landscape with these towers is unsightly. Can kill birds - migrating flocks tend to like strong winds. However, this is rare,

and we tend not to build wind farms on migratory routes anyway. Can affect television reception if you live nearby. Can be noisy. Wind generators have a reputation for making a constant, low,

"swooshing" noise day and night, which can drive you nuts.Having said that, as aerodynamic designs have improved modern wind farms are much quieter. A lot quieter than, say, a fossil fuel power station; and wind farms tend not to be close to residential areas anyway. The small modern wind generators used on boats and caravans make hardly any sound at all.

1.2.8 Wave power:

Ocean waves are caused by the wind as it blows across the sea. Waves are a powerful source of energy.

The problem is that it's not easy to harness this energy and convert it into electricity in large amounts. Thus, wave power stations are rare.1.2.8.1 How it works:

There are several methods of getting energy from waves. One of them works like a swimming pool wave machine in reverse.

At a swimming pool, air is blown in and out of a chamber beside the pool, which makes the water outside bob up and down, causing waves.

At a wave power station, the waves arriving cause the water in the chamber to rise and fall, which means that air is forced in and out of the hole in the top of the chamber. We place a turbine in this hole, which is turned by the air rushing in and out. The turbine turns a generator.

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A problem with this design is that the rushing air can be very noisy, unless a silencer is fitted to the turbine. The noise is not a huge problem anyway, as the waves make quite a bit of noise themselves.

Example:

Another company is called Renewable Energy Holdings. Their idea for generating wave power (called "CETO") uses underwater equipment on the sea bed near the coast. Waves passing across the top of the unit make a piston move, which pumps seawater to drive generators on land. They're also involved with wind power and bio fuel.

1.2.8.2 Advantages:

The energy is free - no fuel needed, no waste produced.

Not expensive to operate and maintain. Can produce a great deal of energy.

1.2.8.3 Disadvantages:Depends on the viscous dissipation at the seabed and in turbulence. This loss of

energy has caused the rotation of the Earth to slow in the 4.5 billion years since formation. During the last 620 million years the period of rotation has increased from 21.9 hours to the 24 hours. we see now; in this period the Earth has lost 17% of its rotational energy. While tidal power may take additional energy from the system, increasing the rate of slowdown, the effect would be noticeable over millions of years only, thus being negligible.

12.9 Tidal Power:

1.2.9.1 Energy calculations:

Various turbine designs have varying efficiencies and therefore varying power output. If the efficiency of the turbine "Cp" is known the equation below can be used to determine the power output.

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The energy available from these kinetic systems can be expressed as:

P = Cp x 0.5 x ρ x A x V³

Where:

Cp is the turbine coefficient of performance P = the power generated (in watts) ρ = the density of the water (seawater is 1025 kg/m³) A = the sweep area of the turbine (in m²)

V³ = the velocity of the flow cubed (i.e. V x V x V Tidal barrages have been built before, whereas this idea is untested so it'll be interesting

to see if it gets approved.

1.2.9.2 Advantages:

Once you've built it, tidal power is free.

It produces no greenhouse gases or other waste. It needs no fuel. It produces electricity reliably. Not expensive to maintain. Tides are totally predictable. Offshore turbines and vertical-axis turbines are not ruinously expensive to build

and do not have a large environmental impact.

1.2.9.3 Disadvantages:

A barrage across an estuary is very expensive to build, and affects a very wide area - the environment is changed for many miles upstream and downstream. Many birds rely on the tide uncovering the mud flats so that they can feed. There are few suitable sites for tidal barrages.

Only provides power for around 10 hours each day, when the tide is actually moving in or out.

1.2.10 Biogas power:

Methane gas produced during digestion (the decomposition of organic materials by microorganisms in anaerobic condition) in the sludge treatment process is used as fuel of power generation. This power is then used at water reclamation centers. Through this, it is possible to use energy efficiently, reduce power costs, and reduce greenhouse gas emissions.

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1.2.10.1 How it works:

For bio mass power station making electricity, it's pretty much like a fossil fuel power station.

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Sugar cane is harvested and taken to a mill, where it is crushed to extract the juice. The juice is used to make sugar, whilst the left-over pulp, called "bag ace" can be burned in a power station.

The station usually provides power for the sugar mill, as well as selling electricity to the surrounding area.

2008: plans have just been announced by tree energy company Eon for a biomass-fuelled power station Port buries, near Bristol. The fuel would be wood, brought in by boat, and the station would produce 150MW of electrical power.

It is claimed that bio fuels will help us to reduce our reliance on fossil-fuel oil, and that this is a good thing.

On the other hand, it is also claimed that it takes a huge amount of land to grow enough crops to make the amount of bio fuels we'd need, so much so that it makes a big dent in the amount of land available for growing food.

Who is right? Should we be using more bio fuels and less fossil fuel? Think about the carbon dioxide - there are similar CO2 emissions from bio fuel-powered vehicles as from petrol-powered ones.

It is claimed that growing plants to make bio fuels will take in that carbon dioxide again. But biologists tell us that forests are not 'the lungs of the planet' after all - they give out as much CO2 as they absorb as the plants respire. It seems that its plant plankton in the oceans that takes in most CO2 and gives out most oxygen.

1.2.10.2 Advantages: 

It makes sense to use waste materials where we can.

The fuel tends to be cheap. Less demand on the fossil fuels.

1.2.10.3 Disadvantages:

Collecting or growing the fuel in sufficient quantities can be difficult.

We burn the bio fuel, so it makes greenhouse gases just like fossil fuels do. Some waste materials are not available all year round.

1.2.11 Geo thermal power:

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Geothermal power generation is an environment-friendly power generation system that capitalizes on geothermal resources that are domestically produced energy.

Geothermal energy is a top source of renewable energy, better than solar or wind. When the wind doesn’t blow and the sun doesn’t shine, the heat from the volcano continues to produce a steady flow of power.

Geothermal resources are found in three types of locations: in shallow ground; in the hot water and rock located a few miles beneath the earth’s surface; and even deeper into the earth where molten rock reaches extremely high temperatures.

Today we drill wells into the geothermal reservoirs to bring the hot water and steam to the surface. Geologists and engineers do a lot of exploring and testing to locate underground areas that contain this geothermal resource, so we’ll know where to drill production and injection wells. Once the hot water and/or steam travel up the wells to the surface, they can be used to generate electricity or for other energy-saving purposes.

This heat, called geothermal energy, provides warmth and power without polluting the environment.

The heat from Earth’s core continuously flows outward. When temperatures and pressures become high enough, some of the surrounding rock melts, becoming magma. Because it is lighter, the magma rises, moving slowly up toward Earth’s crust, carrying with it the heat from below.

Sometimes the hot magma reaches the surface, where we know it as lava. Kilauea Volcano on the Big Island of Hawaii, for example, has been actively spewing lava since the 1980s. Most often the magma remains below Earth’s crust, heating nearby rock, rainwater and seawater that have seeped deep into the earth. Some of this hot water travels back up through faults and cracks and reaches Earth’s surface as hot springs or geysers. Most of it stays deep underground, trapped in cracks and porous rock. This natural collection of hot water is called a geothermal reservoir.

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Once geothermal waters reach the surface, the steam is sent to the power plant and used to drive generators to produce electricity, and the brine and gases are re-injected back into the injection zone below the water table. Combined, Puma Geothermal Venture’s five production wells normally produce an average of two million pounds of geothermal fluid per hour. Like wells in other volcanic regions (Indonesia, Philippines and Iceland), PGV’s wells are considered prolific in comparison to other types of geothermal wells in the industry.

There are three types of power-generating plants: dry steam, flash steam and binary cycle. Dry steam plants, first used in Italy more than 100 years ago, route the steam directly to a power plant to produce electricity. Dry steam plants are used in places such as The Geysers in California, where steam is close to the surface. Flash steam power plants cause the fluid to rapidly vaporize, driving turbines that in turn drive a generator. Binary-cycle plants are similar and the most advanced. Their closed-loop circulation system means that no excess gases or fluids reach the open air. PGV’s power plant utilizes the closed-loop binary system.

1.2.11.1 Advantages

Krafla Geothermal Station in northeast IcelandGeothermal power requires no fuel, and is therefore virtually emissions free and

insusceptible to fluctuations in fuel cost. And because a geothermal power station doesn't rely on transient sources of energy, unlike, for example, wind turbines or solar panels, its capacity factor can be quite large; up to 90% in practice.

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It is considered to be sustainable because the heat extraction is small compared to the size of the heat reservoir. While individual wells may need to recover, geothermal heat is inexhaustible and is replenished from greater depths. The long-term sustainability of geothermal energy production has been demonstrated at the Lardarello field in Italy since 1913, at the Waunakee field in New Zealand since 1958, and at The Geysers field in California since 1960.

Geothermal has minimal land use requirements; existing geothermal plants use 1-8 acres per megawatt (MW) versus 5-10 acres per MW for nuclear operations and 19 acres per MW for coal power plants. It also offers a degree of scalability: a large geothermal plant can power entire cities while smaller power plants can supply more remote sites such as rural villages.

1.2.11.2 Disadvantages:

From an engineering perspective, the geothermal fluid is corrosive and, worse, is at a low temperature compared to steam from boilers. By the laws of thermodynamics this low temperature limits the efficiency of heat engines in extracting useful energy during the generation of electricity. Much of the heat energy is lost, unless there is also a local use for low-temperature heat such as greenhouses, timber mills, and district heating. However, since this energy is almost free once the plant is established, the efficiency of the system is not as significant as for a coal or other powered plant.

There are several environmental concerns behind geothermal energy. Construction of the power plants can adversely affect land stability in the surrounding region. This is mainly a concern with Enhanced Geothermal Systems, where water is injected into hot dry rock where no water was before. Dry steam and flash steam power plants also emit low levels of carbon dioxide, nitric oxide, and sculpture, although at roughly 5% of the levels emitted by fossil fuel power plants. However, geothermal plants can be built with emissions-controlling systems that can inject these substances back into the earth, thereby reducing carbon emissions to less than 0.1% of those from fossil fuel power plants. Hot water from geothermal sources will contain trace amounts of dangerous elements such as mercury, arsenic, and antimony which, if disposed of into rivers, can render their water unsafe to drink.

Although geothermal sites are capable of providing heat for many decades, locations may eventually cool down. For example, the world's second-oldest geothermal generator at Waunakee has reduced production. It is likely that locations like these were designed too large for the site, since there is only so much energy that can be stored and replenished in a given volume of earth. If left alone, however, these places should recover their lost heat, as the Earth's mantle and core have vast heat reserves. Geothermal and biomass are the only two renewable resources which must be carefully managed in order to avoid local depletion. An assessment of the total potential for electricity production from the high-temperature geothermal fields in Iceland gives a value of about 1500 TWh (total) or 15 TWh per year over a 100 year period. The electricity production capacity from geothermal fields is now only 1.3 TWh per year.

1.2.12 Coal Gasification:

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Is this a new technology?

Coal gasification is a well-proven technology dating back to the 18th century, although its uses have evolved significantly since then. Interest in coal gasification has wavered in the U.S. during times when the price and availability of competing fuel sources-oil and natural gas-were low. However, recent advancements in gasification technology, increasing costs of oil and gas, growing concerns about energy security, and a heightened awareness of climate change, have all led to a renewed interest in coal gasification for electric power generation in the U.S. and many other countries.

Worldwide there are just four integrated gasification combined cycle (IGCC) plants running on coal today: one in Puerto llano, Spain, one in Belgium, Netherlands, one near Terre Haute, Indiana, and one in Polk County, Florida. So while the technology is not new, our experience with commercial-scale IGCC plants is limited. Fourteen will also be advancing the technology. There is still much to learn, particularly about the economics of operating a commercial-scale plant.

Future Gen will be an IGCC power plant. IGCC is an innovative technology that combines modern coal gasification with a gas turbine and a steam turbine to produce electric power. It is one of the most promising technologies available today for reducing the environmental impacts associated with the use of coal for electricity production.

1.2.12.1 What are the advantages of IGCC technology?

Coal-fueled IGCC technology offers a number of potential benefits over conventional pulverized coal plants. Depending on the final configuration of the IGCC plant, these can include:

Higher efficiency - The use of two turbines—a gas turbine and a steam turbine—leads to higher system efficiencies

Lower emissions - The gasification process enables improved removal of naturally-occurring pollutants in coal, such as sulfur and mercury, resulting in lower emission than conventional coal based power plants.

Carbon sequestration potential - The IGCC process makes it easier to capture carbon dioxide for carbon sequestration.

Marketable byproducts - The byproducts associated with the gasification and gas clean-up process may have commercial value in nearby industries.

Hydrogen as an alternative fuel source - Hydrogen is gaining popularity as a potential clean-burning fuel source of the future for vehicles and other industries. The ability to produce hydrogen from coal for such future applications could prove to be an important benefit of IGCC technology.

1.2.12.2 How do coal –based IGCC power plants work?

As illustrated in the figure below, IGCC power plants involve a complex chain of activities that start with a carbon-based material—in the case of Future Gas, coal—and result in electricity that power our homes and businesses.

1. The coal gasification process begins with a controlled mixture of coal, oxygen, and steam in a gasified. An air separation unit separates air into its component parts to supply the gasified with a stream of oxygen.

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2. Using a combination of heat and high pressure, the gasified converts the constituents of coal into a synthetic gas, or "singes". This singes is comprised of mostly hydrogen (H2) and carbon monoxide (CO).

3. Byproducts captured in the gasified could have commercial value, depending on local market conditions. For example, the Future Gen plant could produce an ash material similar to what comes from a traditional coal plant. This ash may be used as a filler material in construction projects and building products. Alternatively, Future Gen may produce a glass-like material, known as "slag", which falls to the bottom of the gasified. This slag may be used in road gravel.

4. The singes is then passed through a water gas shift reactor and reacted over a catalyst with added steam to convert the majority of the CO into carbon dioxide (CO2) and additional H2.

5. The singes will also have small amounts of other impurities (e.g. hydrogen sulfide) which are removed during the gas clean-up process.

6. Hydrogen sulfide will be separated from the singes and converted to elemental sulfur or possibly sulfuric acid. The sulfur byproducts may also have commercial value in a variety of products (e.g. fertilizer), depending on local market opportunities.

7. Most of the CO2 is removed from the singes leaving behind H2-rich singes. 8. One of the things that make IGCC plants more efficient is the combined use of a

gas turbine and steam turbine to produce electricity. The hydrogen-rich singes is first fed into a gas turbine to generate electricity. The waste heat from the gas turbine is used to power a steam turbine, which in turn creates more electricity. Finally, much of the water used in this process will be recycled in the plant some will be evaporated in a cooling tower

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ChapterNumber

2

Hydro Power Generation

Water plays a very special part in the creation of electricity. Hydroelectricity – when the power of falling water is turned into electricity has been used for hundreds of years and is one of the most efficient ways to produce electricity. It's also good for the environment because it is a renewable energy source that has little environmental impact and does not emit greenhouse gases.Hydroelectricity is an important part of NB Power's generation system. We currently have 7 hydro stations throughout New Brunswick, which accounts for half of all of NB Power's generation stations.

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In a hydro station, water falls down a chute called the penstock and flows over the blades of a turbine. The falling water turns the blades, which are attached to the magnets by the generator shaft. The spinning blades turn the magnets, which creates electricity in the wire coils.

2.1 Hydro TourHydro electricity makes up more than 20 per cent of the total capacity of the generation system. It's an important part of the system because it decreases generation costs, while providing a renewable energy source that has little environmental impact and does not emit greenhouse gases.

2.1.1 Nepisiguit FallsNB Power purchased Nepisiguit Falls Generating Station in June 2007. The station's first two units were built in 1921, with the addition of a third unit in 1929. The Station has a total capacity of 10.8 MW.

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2.1.2 SissonAlthough the Sisson Generating Station is small, its unique storage dam acts as a regulator for water flowing to the Tobique Narrows Generating Station. The storage reservoir at Sisson, 112 kilometres upstream from Tobique, is the largest of the four storages in the Tobique River watershed. The water is supplied to the Powerhouse through a 442 metre long steel penstock.

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2.1.3 Grand Falls The town of Grand Falls is situated on a plateau with the river flowing around it in The form of a horseshoe. The natural falls and gorge are in the bend of the horseshoe. The dam is at the top of the falls, with the water intake feeding a pressure tunnel that runs under the town to the powerhouse. A number of observation decks are located to give the best views of the falls and the gorge. A natural trail stretching along the gorge also provides a good view of the falls.

 

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2.1.4 Tobique The Tobique Narrows Generating Station takes it name from one of the largest tributaries of the upper Saint John River. The station was completed in 1953 and has a capacity of 20 MW. A roadway sits atop the dam serving as a bridge. The station has a fish ladder, a series of steps that allow Atlantic Salmon to swim from the lower level of the dam to the waters of the Tobique and their spawning grounds.

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2.1.5 Beachwood The 113 MW Beechwood Generating Station, located on the Saint John River 160 kilometres north of Fredericton, is a symbol of beauty and efficiency. The floral clock located here is a popular tourist attraction. The clock is 9 meters in diameter with a 4 meter minute hand and a 3 meter hour hand. It is run by power from the dam and is operated by a motor in a small room underneath the clock. The clock stands in a garden, which contains a collection of many native New Brunswick trees.  

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2.1.6 Mactaquac Mactaquac is the largest hydroelectric generating station in the Maritime Provinces and is located 19 kilometres up the Saint John River from Fredericton. "Mactaquac", a Maliseet word meaning "big branch", was the name given to the stream that flows into the Saint John River, and now forms part of the Mactaquac headpond. The headpond offers ample recreational activities throughout the year. Fish collection facilities have been incorporated at Mactaquac to help the river's salmon stocks.

 

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NB Power purchased Nepisiguit Falls Generating Station in June 2007. The station's first two units were built in 1921, with the addition of a third unit in 1929. The Station has a total capacity of 10.8 MW.

2.1.7 MilltownNB Power's first hydro plant was the Milltown Generating Station. The station is located on the St. Croix River, which forms the south western international boundary between New Brunswick and Maine. When originally built it 1881, the plant contained a 500 horse power water wheel with equipment attached by the traditional rope drive method. A new dam was built in the early 1900s.

2.2 LocationsCountries with the most hydroelectricity used China, Canada, Brazil, USA, Russia, Norway, India, Japan, Sweden, and France. Hydroelelectricity is found mostly in three states; California, Oregon and Washington. Although there are a

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few other states that can create this form of electricity, these three states create over1/2 of the total power found by water.

2.3 Hydro electric- how it works

Hydroelectricity is made when a dam is built in a high water flow area. The water then builds up behind the dam; a fan blows water into the turbine area, spinning the turbine generating electricity. The energy is then wired to a powerhouse,

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which sends it out to the millions of people waiting for it.

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2.4HydroPowerGeneratinThe use of VSI Generators for hydropower generation will be extensive. Generally, wherever induction generators are or would be installed, the VSI Generator will displace the use of those generators. More importantly, the use of VSI Generators will expand seasonal hydro generation output and provide opportunities for development of hydro sources which otherwise would not be tapped.

2.5 Displacement of Synchronous GeneratorsSynchronous generators are used where a large dam can be constructed to ensure relatively constant water flow. This is necessary because with synchronous generators the hydro turbine must be operated precisely and constantly to deliver synchronous rpm to the generator. The VSI Generator can use hydro resources without the need for elaborate gates and hydro governor systems which add cost and reduce overall hydro efficiency.

2.6 Displacement of Induction GeneratorsInduction generators are currently used in locations where water flow cannot be constantly adjusted to ensure constant turbine torque and in situations where synchronous generators cannot be cost-justified, as is the case with small to intermediate hydro developments of less than 15 megawatts. In these smaller hydropower developments all over the world, which would otherwise employ induction generators, a great potential for the deployment of VSI Generators exist. In hydro applications there are several advantages, which the VSI Generator has over the induction generator. Most importantly, the VSI Generator will operate at various speeds without the need for water flow controls and synchronizing equipment. With the VSI Generator, hydro plants can expand their operating range and efficiency. The VSI Generator can enable a hydro plant to generate power over more months of the year.Moreover, whenever water resources are available that would otherwise over-speed or under speed an induction generator, power can be produced through the VSI Generator without incident. Furthermore, generator load capability can be more economically matched to hydro turbine output to increase overall turbine generator efficiency. With the VSI Generator, costly and complex synchronizing equipment will also not be necessary. Thus, in a vast number of cases, hydropower will provide superior cost effectiveness with the use of VSI Generators. In addition, the number of hydropower applications can be significantly increased through the use of the VSI Generator. Many low head hydro sources such as paddle wheels, mining sluices and Pelt on wheels on smaller rivers, streams and waterfalls which were previously untarnished can now become cost effective sources of utility compatible power.

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2.7 Problems faced by Hydroelectric DevelopersHydroelectric power theoretically, is one of the least expensive sources of electric energy, because water (the prime mover) is free of cost and is also consistent. However, with the fluctuations associated with water flow and the conventional generation systems used, installation of a hydroelectric plant is a very expensive and time-consuming venture. Consider the cost, with the price of land under the reservoir, the cost of constructing a dam and its bypass, as well as the maintenance of the reservoir, the dredging of silt that constantly is added by sedimentation of the impounded water and environmental issues that result from the damming of a river. These are major problems facing most of the hydroelectric developers today. With the use of the VSI Generator all of these costs become unnecessary because there is no need for the impounding of water, the construction of the dam and bypass and the maintenance of the lake. By having a project use just the natural flow of the river; you can commence the operation and production of electric energy immediately without the high cost and development time associated with the construction of a conventional dam. By using turbines that convert the moving water into mechanical energy, the VSI Generator will produce electric energy without any other equipment. Furthermore, with the use of low speed turbines you may install thousands of smaller units along the course of a river without restricting its natural flow and also increase the electric output as the demand continues to increase. This cannot be accomplished with the conventional generator and the impounding of water because the amount of the power is fixed to the capacity of the dam itself.

2.8 Hydel Generation

As a consequence of partition of the Indo-Pakistan Sub-Continent in 1947, India and Pakistan became two independent sovereign states. Hydel generation capacity of only 10.7 MW (9.6 MW - Malakand Power Station & 1.1 MW - Renal a Power Station) existed in the territory of Pakistan. With the passage of time, new Hydel Power Projects of Small and Medium capacities were commissioned including the first water storage dam and power house at Warsaw due to which country's Hydel capability raised to about 267 MW up till 1963. The Irrigation System which existed at the time of partition in 1947 was divided between the two countries without any regards to the irrigation boundaries which resulted in an international water dispute which was finally resolved by signing of the Indus Water Treaty in 1960 under the aegis of World Bank. The Treaty assigned three Eastern rivers (Ravi, Beas and Sutlej) to India and three Western rivers (Indus, Jhelum & Chenab) to Pakistan. It also provided construction of replacement works called Indus Basin Projects (IBP) to compensate for perpetual loss of Eastern Rivers' water. The works proposed under the Treaty included two multipurpose dams i.e. Mangla Dam on Jhelum River and Tarbela Dam on Indus River having the provision of power generation. These were commissioned in

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1967 & 1977 respectively. However, their capacities were subsequently extended in different phases.

2.9 Hydel Generation Capacities

The total capacity of 13 No. Hydel Stations as of today is 6443.56 ~ 6444 MW which is 37.10% of total installed generation capacity of WAPDA. During 2007~2008, aggregate energy sharing during the year was 33.32%. The Hydel Generation Capacity was reduced from 6463.16 MW to 6443.56 MW due to decommissioning of Jabban Hydel Power Station after a fire incident in November, 2006.

2.10 Seasonal Variations of Hydel Generation

The seasonal variations of reservoir levels and consequent reduction in Power outputs of storage type hydel projects in Pakistan are very pronounced. Tarbela with maximum head of 450 ft. experiences variation of 230 ft. while Mangla has 162 ft. variation against the maximum head of 360 ft.The lean flow period of Tarbela reservoir is from November to June when the Capability reduces to as

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low as about 1350 MW against the maximum of 3692 MW during high head period i.e. August to September (15% permissible overloading on Units 1~10).Lean flow period of Mangla reservoir is observed from October to March when the minimum generating capability is 500 MW. The capability rises to as high as 1150 MW during 'high head' period (15% permissible overloading).In all, WAPDA's Hydel generating capability varies between the two extremities of 2414 MW and 6746.0 MW over the cycle of a year.

2.11Statistics

The next few pages provide information about the salient features of WAPDA Hydel Stations, their locations, statistical data etc. which are titled as under:

a. Location of Hydel Stations in PAKISTAN. b. Installed Capacities of WAPDA's Hydel Stations. c. Performance of Hydel Generation 2007~2008(Financial Year) d. Salient Features e. Mangla Dam f. Tarbela Dam g. Warsak Dam h. Chashma Hydropower Project

2.12 Performance of HYDEL POWER STATIONS

TarbelaInstalled Capacity 3478   MW

Effective Capacity (Max.) 3702   MW

Effective Capacity (Min.) 1350   MW

Energy Generation 14959.18   GWH

Auxiliary Consumption 69.79   GWH

Maximum Load 3702   MW

Plant Factor 49.1   %

Availability Factor 94.67   %

0  

ManglaInstalled Capacity 1000   MW

Effective Capacity (Max.) 1150   MW

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Effective Capacity (Min.) 500   MW

Energy Generation 4687.333   GWH

Auxiliary Consumption 118.887   GWH

Maximum Load 1150   MW

Plant Factor 53.51   %

Availability Factor 92.54   %

0  

WarsakInstalled Capacity 243   MW

Effective Capacity (Max.) 231   MW

Effective Capacity (Min.) 100   MW

Energy Generation 1050.042   GWH

Auxiliary Consumption 23.71   GWH

Maximum Load 208   MW

Plant Factor 49.33   %

Availability Factor 84.51   %

0  

ChashmaInstalled Capacity 184   MW

Effective Capacity (Max.) 184   MW

Effective Capacity (Min.) 24.8   MW

Energy Generation 987.494   GWH

Auxiliary Consumption 1.32   GWH

Maximum Load 184   MW

Plant Factor 61.27   %

Availability Factor 85.2   %

0  

DargaiInstalled Capacity 20   MW

Effective Capacity (Max.) 18.8   MW

Effective Capacity (Min.) 2   MW

Energy Generation 145.571   GWH

Auxiliary Consumption 0.358   GWH

Maximum Load 18.8   MW

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Plant Factor 83.09   %

Availability Factor 93.99   %

0  

Malakand (Jabban)Installed Capacity 0   MW

Effective Capacity (Max.) 0   MW

Effective Capacity (Min.) 0   MW

Energy Generation 0   GWH

Auxiliary Consumption 0   GWH

Maximum Load 0   MW

Plant Factor 0   %

Availability Factor 0   %

0  

RasulInstalled Capacity 22   MW

Effective Capacity (Max.) 17   MW

Effective Capacity (Min.) 1   MW

Energy Generation 36.566   GWH

Auxiliary Consumption 3.351   GWH

Maximum Load 15.6   MW

Plant Factor 18.97   %

Availability Factor 90.35   %

0  

ShadiwalInstalled Capacity 13.5   MW

Effective Capacity (Max.) 8   MW

Effective Capacity (Min.) 1.4   MW

Energy Generation 43.63   GWH

Auxiliary Consumption 1.123   GWH

Maximum Load 8   MW

Plant Factor 36.89   %

Availability Factor 93.74   %

0  

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NandipurInstalled Capacity 13.8   MW

Effective Capacity (Max.) 8.7   MW

Effective Capacity (Min.) 1.8   MW

Energy Generation 29.056   GWH

Auxiliary Consumption 1.414   GWH

Maximum Load 8.6   MW

Plant Factor 24.04   %

Availability Factor 80.44   %

0  

ChichokiInstalled Capacity 13.2   MW

Effective Capacity (Max.) 9   MW

Effective Capacity (Min.) 2   MW

Energy Generation 19.703   GWH

Auxiliary Consumption 2.236   GWH

Maximum Load 7   MW

Plant Factor 17.4   %

Availability Factor 90.8   %

0  

K/GarhiInstalled Capacity 4   MW

Effective Capacity (Max.) 4   MW

Effective Capacity (Min.) 2.6   MW

Energy Generation 17.859   GWH

Auxiliary Consumption 1.346   GWH

Maximum Load 4   MW

Plant Factor 50.97   %

Availability Factor 87.7   %

0  

RenalaInstalled Capacity 1.1   MW

Effective Capacity (Max.) 1.1   MW

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Effective Capacity (Min.) 0.28   MW

Energy Generation 3.339   GWH

Auxiliary Consumption 0.041   GWH

Maximum Load 0.71   MW

Plant Factor 34.66   %

Availability Factor 70.98   %

0  

ChitralInstalled Capacity 1   MW

Effective Capacity (Max.) 1   MW

Effective Capacity (Min.) 1   MW

Energy Generation 4.851   GWH

Auxiliary Consumption 0.027   GWH

Maximum Load 1.077   MW

Plant Factor 55.39   %

Availability Factor 76.89   %

0  

Ghazi BarothaInstalled Capacity 1450   MW

Effective Capacity (Max.) 1450   MW

Effective Capacity (Min.) 1100   MW

Energy Generation 6573.701   GWH

Auxiliary Consumption 103.545   GWH

Maximum Load 1450   MW

Plant Factor 51.75   %

Availability Factor 96.46   %

0  

We thought you might like to find out what happens inside our hydro stations. For your convenience, this tour provides a 360 degree virtual environment. Pages may take a few seconds to load using a high-speed connection.

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CHAPTER NUMBER

3

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Electricity produced by damsHydro-electric dams produce 10% of our nations electricity and 80% of the electricity produced from renewable resources.The building of hydro-electric dams affects our rivers, wildlife, and environment. By building new dams we make man made lakes which means we have to backup the river water. This damages the surrounding environment by cutting off the large water supply farther downstream, flooding the environment by the dam with the backed up water, and digging up the environment for the dam and lake. Therefore the building of dams has to be reviewed case-by-case.Also the building of dams is not only an environmental problem in some place but also an economical one. It cost a great deal of money to build a single dam.

The qualities of the dams are based off of the following criteria:River flows,Water quality Fish passage and protection Watershed protection Threatened & endangered species protection Cultural resource protection Recreation Facilities recommended for removal

There are three kinds of hydro-electric dams in the U.S.1-'Storage' Dams- store water in reservoirs that runs there turbines.2-'Run-of-Rivers' Dams- river runs through a powerhouse, producing electricity but also changing the river's water level.3-'Pumped-Storage' Dams- uses off-peak electricity to pump water from a lower reservoir to an upper reservoir and in times of high electrical need it dumps the water back into the low reservoir.

3.1 Dam failuresFailures of large dams, while rare, are potentially serious the Banqiao Dam failure in Southern China resulted in the deaths of 171,000 people and left millions homeless. Dams may be subject to enemy bombardment during

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wartime, sabotage and terrorism. Smaller dams and micro hydro facilities are less vulnerable to these threats. The creation of a dam in a geologically inappropriate location may cause disasters like the one of the Vermont Dam in Italy, where almost 2000 people died, in 1963.

3.2 DisadvantagesThe disadvantages of water as a power source are as followed, one it affects ecology and causes down stream problems. The second thing is dams can also alter the natural river flow and affect wildlife. The third problem would be that oxygen poor water can be released into the river, and kill many fish.

3.3 Comparison 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 aRenewable energy source.

Water as a power source is used more in Canada than in America.

How much of nations power is used for water?10% of total power is produced by hydroelectric plants.What are the advantages of water as a power source?Fuel is not burned so there is minimal pollution, Water to run the power plant is provided free by nature, its renewable-rainfall renews the water in the reservoir, so the fuel is almost always there.How is water made?A solvent is a liquid capable of dissolving another substance. A polar molecule is one that has positive and negative regions.

3.4 What do we mean by water quality impacts?Water bodies come in many forms: huge oceans; large and small lakes; and a diversity of rivers and streams. Each of these ecosystems features a tapestry of waterborne species that are all dependent upon a high degree of water quality. These bodies of water are also essential to human survival and public health. For example, underground aquifers often supply us with drinking water. Waterways

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are also not only key transportation routes for billions of dollars in global commerce, but they represent popular opportunities for recreation in the form of fishing, boating and water sports. Some particularly pristine spots in or near ocean, lakes and rivers may be candidate for long-term preservation because of their stunning aesthetic values.The construction and continued operation of power plants, particularly those fueled by fossil or nuclear fuels, are among the human activities that can have the most profound and wide ranging negative impacts on water quality.

3.5How can electricity production impairs water quality?The following procedures all can occur during routine operations and maintenance of power plants and each can significantly impact water quality: Boiler blow down: This waste stream results from periodic purging of the impurities that become concentrated in steam boiler systems. These pollutants include metals such as copper, iron and nickel, as well as chemicals added to prevent scaling and corrosion of steam generator components. Coal pile run-off: This waste stream is created when water comes in contact with coal storage piles maintained on the power plant site. While most piles are kept covered, active piles used to meet the power plants immediate needs are often open to the elements. Metals and other naturally occurring contaminants contained in coal leach out with the rainfall and are deposited in nearby water bodies.

3.6 Cooling process wastes:Water used for power plant cooling is chemically altered for purposes of extending the useful life of equipment and to ensure efficient operation. Dematerialized regenerates and rinses are chemicals employed to purify waters used as makeup water for the plant's cooling system. Cooling tower blow down contains chemicals added to prevent biological growth in the towers and to prevent corrosion in condensers.

3.7 Boiler cleaning wastes:These wastes derive from the chemical additives intended to remove scale and other byproducts of combustion. Thermal pollution: Thermal plants create or use steam in the process of creating electricity require water for cooling. This water typically comes from adjacent water bodies or groundwater sources and is discharged back into the water body at significantly higher temperatures. By altering the temperature in the "mixing zone," the discharge of thermal wastewater can both negative and positive effects on aquatic life. On the plus side, the warmer temperature water may create more favorable feeding and breeding conditions for certain species located near the power plant's water source. However, when the power plant is suddenly shut down for routine maintenance or unplanned outage, the resulting wide swing to colder temperatures can be lethal to sensitive fish populations.

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Hydropower dams can also alter the natural temperature of the water, as discussed above.

3.8 What are the impacts of power production on water quality? Many large central station fossil and nuclear power plants rely upon water for cooling and are therefore located near bodies of water. In some instances, the diversion of rivers creates reservoirs adjacent to power plants for cooling, rinsing and the releases of effluents. A variety of processes associated with fuel handling and ongoing maintenance of large thermal power plants create or concentrate chemical pollutants that are then discharged into nearby water bodies. Even when releases are limited to what is allowed in water use permits; there is still the occasional but inevitable accidental release.Both of these sources of pollution can be legal and alone can cause significant harm to streams, rivers, lakes, estuaries and groundwater. Water quality can degrade to the point where fish and other aquatic life populations decline - even when power plant operators abide by water permit restrictions. Often, the water used in the power plant is also being diverted from other "higher" uses such as recreation or tourism, drinking water supplies, and other less intrusive commercial opportunities. In addition, the habitat of many animal and plant species can be destroyed during the construction of and continued operation of large fossil and nuclear power plants. These same facilities represent challenges to maintaining a sense of aesthetics in scenic environments.

3.9 Construction and operation of hydropowerConstruction and operation of hydropower facilities can also have negative impacts on water quality. By slowing the river's flow, most dams increase water temperatures. Other dams decrease temperatures by releasing cooled water from the reservoir bottom. Fish and other species are sensitive to these temperature irregularities, which often destroy native populations. These temperature changes, when combined with water stagnation, may also lead to the accumulation of decaying materials in the reservoir and a corresponding loss of oxygen, which then increases substances toxic to aquatic wildlife in the reservoir. And when this oxygen-deprived water is released from behind the dam, it can kill fish and vegetation downstream. Alternatively, water falling over spillways to spin turbines to generate electricity can super-saturate the water with gases from the surrounding air. The gas bubbles, which are absorbed into fish

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tissue, may cause damage and ultimately kill the fish. Crystal-clear rivers can also degrade quickly when water is impounded behind a man-made dam, accumulating sediment and silt.

3.10 Impact of fish and wildlifeHydropower dams also impact fish and wildlife habitat. Construction of a dam converts river habitat into a lake-like reservoir. This often eliminates native populations of fish and other wildlife. Warm, slow moving reservoirs also often favor predators of naturally occurring species. It has been argued that reservoirs can enhance waterfowl habitat, but such artificially created habitats may be of considerably lower quality than the naturally evolved and undisturbed river systems. Peaking power operations can also cause dramatic changes in reservoir water levels -- often up to 40 feet -- that degrade shorelines and disturb fisheries, waterfowl, and bottom-dwelling organisms. (See also Hydropower Generation, Water Consumption and Land Impacts Issue Papers for more information on hydropower impacts.)

3.11 How can consumer electricity choice address water quality problems?Water quality impacts vary - sometime significantly - from electricity generating technology to technology. Many renewable energy technologies such as wind and solar photovoltaic technology produce electricity without generating any waste effluent released into waterways or without relying upon any cooling water. By contrast, thermal power plants that run on coal and other fossil fuels introduce a myriad of chemicals for maintenance or operational purposes, and through combustion, liberate other chemicals from the fuel that wind up in the power plant's discharge. Nuclear power plants consume even more water than fossil fuel facilities because of the additional cooling requirements of reactor cores and can have major impacts on marine environments. Consumers can help maintain the sustainability of rivers and streams, lakes and oceans, by ensuring that their power comes from low impact and renewable sources that do not rely upon water for cooling. Some renewable resources, such as solar thermal facilities or geothermal power plants may require cooling water and therefore may have more of an impact than those other renewable sources that lack any need for water cooling. Most renewable resources, however, are smaller than coal and nuclear power plants and therefore their negative impacts on water bodies are considerably less.

3.12 What are the land impacts of generating electricity?3.12.1On-siteThe gigantic central-station, electric generating facilities that provide the vast bulk

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of the electricity in the US can occupy acres upon acres of land just for the power plant components alone. These power plants also require on-site fuel storage facilities as well as structures for connecting to the transmission grid, which requires additional land. Depending on the fuel burned at any one power plant, electricity generators can leave their sites irrevocably scarred or polluted. Construction of hydropower dams floods riverside lands, permanently eliminating riparian and upland habitat. All of these are known as on-site land impacts.

3.12.2Off-siteMost generating facilities also produce solid waste by-products of combustion that can be toxic. Solid wastes from power plants are typically land filled, another way in which a generating facility impacts land as it extends its environmental footprint beyond the boundaries of the power plant site. In this case, the waste will likely remain at the landfill forever. Mining, collecting and transporting the natural gas, coal, oil, and nuclear fuel necessary to generate electricity can also impact land in much the same way by precluding other uses and leaving permanent scars. All of these are known as off-site land impacts.

3.12.3On-site issues degrade and devalue the landThe average life expectancy of power plants today is 40 years or more. This figure translates into a potentially major reduction in the value of the land around the site for at least that period of time. Even following decommissioning, power plants can leave indelible scars if fuel was stored on site and the generating facilities leave toxic residues or other forms of pollution, which often can never be completely cleaned up. Power plant sites may become sacrifice zones, sealed off from any future land use due to contamination linked to the operation of a power plant.

3.12.4 Off-site issues have far-reaching impacts on ecosystems and aestheticsThe mining, collection and transporting of fuel can impose severe land-use impacts. Natural gas pipelines often traverse private land all across the country, restricting its use and disrupting plant and animal habitat as well as other potential land uses. Coal mining can chew-up whole hillsides and mountains, leaving unsafe and unsightly disruptions of landscapes that may have also represented scenic or recreational values.

3.13 Storage of solid wasteBoth on and off site, can also leave long-lasting marks. Not only does solid waste storage permanently preclude using the land for other purposes, but rain can create leach ate which, if not properly contained, can contaminate nearby

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underground water sources. The impacts of solid waste are, as a general matter, in direct proportion to volume and toxicity. Environmentally sound waste disposal techniques can reduce, but not eliminate, these impacts. The land impacts of hydropower facilities depend on individual dam design, location and operation. Land use and ecosystem impacts of facilities that use large impoundments can be severe. The dam and reservoir may transform the landscape, obliterate sensitive land resources, and permanently alter regional land use patterns. In contrast hydropower facilities can also be designed to limit or offset such impacts.(See also the Hydropower technology page and the Water Consumption and Water Quality issue pages for more information of the land impacts of hydropower.)These negative environmental impacts associated with land use are not as clear-cut a factor in evaluating a power supply option as are air and water impacts. A power plant built on land that is not valued for other uses, and which was sited with the best environmental controls and with full public input and agreement, may produce few significant environmental insults to the land. On the other hand, a nuclear reactor, which leaves behind radioactive wastes that will be with us long after it is decommissioned, imposes land impacts that can exceed concerns over air or water impacts associated with another generating technology.

3.14 How can consumer electricity choice address land impacts? Certain fuel types leave no permanent land impacts. Renewable solar and wind facilities, for example, can be dismantled and removed from sites during decommissioning. Having used no stored fuel, they leave no fuel-related pollution behind. Similarly, these renewable resources eliminate concerns over fuel collection or transportation impacts. Geothermal technologies that uses the earth's heat to generate electricity may also leave few permanent on-site or off-site impacts. If the power plant developer harnessed the heat properly and ensured no contamination of surrounding water supplies, these resources can be decommissioned without leaving behind major on-site land impacts. Geothermal facilities also require no national transportation network for fuel delivery. Biomass facilities that utilize a fuel resource that is sustainable generated, like willow trees grown for fuel, or unfinished wood waste from a furniture manufacturer, also leave few on-site or off site land impacts. Though they do produce solid waste, it is of less toxicity than wastes from fossil fuel resources. Biomass power plants that combust sustainable-generated wood waste streams to create electricity also reduce the amount of solid waste earmarked for landfills, which extends the life of these already crowded facilities. Choosing a power supplier that sells electricity derived from wind, solar or low impact biomass in its mix reduces the direct impacts that your electric supply can have on land. The advent of retail competition offers consumers for the first time the opportunity to directly influence the environmental footprint of electric power production. In several states, suppliers are assembling resource portfolios that

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are significantly cleaner and more dependent upon renewable energy sources. By selecting one of these resource portfolios, you will help ensure that the generation that supplies the power system are those that minimize on-site and off-site land impacts. You will also be sending a powerful signal to power plant developers that consumers prefer that their power supply come from sustainable energy sources.

3.15 Potential environmental impactsHydroelectric facilities disrupt natural river flowsBy diverting water out of the river for power, dams remove water needed for healthy in-stream ecosystems. Stretches below dams may be completely de-watered. By withholding and then releasing water to generate power for peak demand periods, dams may cause downstream stretches to alternate between no water and powerful surges that erode soil and vegetation, and flood or strand wildlife. These irregular releases destroy natural seasonal flow variations that trigger natural growth and reproduction cycles in many species. Peaking power operations can also cause can cause dramatic changes in reservoir water levels - up to 40 feet - that can degrade shorelines and disturb fisheries, waterfowl, and bottom? Dwelling organisms. Dams also slow down the flow of the river. Many fish species, such as salmon, depend on steady flows to flush them downriver early in their life and guide them upstream years later to spawn. Slow reservoir pools disorient migrating fish and significantly increase the duration of their migration. These impacts can, at times, be mitigated by technological and operational enhancements to the hydro project - e.g., minimum flow turbines, re-regulating weirs, and pulsed operation at peak efficiency. Impoundments can be managed to create new upstream and downstream habitat for fish species and to provide minimum discharges and improved habitat during seasonal or annual drought conditions.

3.16Hydropower may alter river and riverside habitatConstruction of a dam can flood riverside lands, destroying riparian and upland habitats. Construction of a dam can also convert river habitat into a lake-like reservoir, threatening native populations of fish and other wildlife. Warm, slow moving reservoirs favor predators of naturally occurring species. Dramatic changes in reservoir water levels, described above, can degrade shorelines and disturb fisheries, waterfowl, and bottom-dwelling organisms.

3.17Dams alter water qualityImpoundments can cause changes and variation in temperature or the amount of dissolved gases in the river.

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Surface temperatures in the reservoir may rise when the flow of the water is slowed. If water is released from the top of the dam, this warmer water may increase river water temperature down stream. Cooler downstream temperatures may result when cool water is released from the bottom of a reservoir. Such altered conditions can affect the habitat, growth rate, or even the survival of fish and other species. For hydropower projects with intakes located deep in the reservoir, water with low dissolved oxygen (DO) levels released to the river downstream may harm aquatic habitat in the river and contribute to other water quality problems. Applying mitigating technologies can improve dissolved oxygen levels. Water sometimes passes over a spillway, rather than through the turbines. As water plunges into the pool at the base of the dam, too much air can be trapped in the water, creating "gas super saturation," a condition that in some fish species fosters something called lethal gas bubble disease. This can be mitigated by installing structures to keep fish away from such areas.

3.18 A dam or a powerhouse can be a significant obstacle to fish migrationLadders or lifts can be installed to pass certain fish species upstream, though multiple dams on a river reduces the success rate of these fish passage devices. Fish migrating downstream can become disoriented, bruised, stressed, or mortally injured from contact with turbines or other parts of the facility. Bypass systems can improve survival rates for migrating juveniles. When fish are trucked or barged around the dams, they may experience increased stress and disease and decreased homing instincts. Survival rates for fish passing through large turbines vary but may approach 90-95 percent. In the case of multiple dams along a river these effects can significantly harm migrating populations of important, sensitive juvenile fish populations. Impoundments also slow down the flow velocities of rivers. Slow reservoir pools may disorient migrating fish, increase the duration of their migration, which in turn may increase their mortality rate. The steep decline in salmon populations in the Pacific Northwest and California is perhaps the best known negative environmental impact associated with hydroelectric facilities. Although several factors have affected this decline - including commercial fish harvests, habitat degradation, and artificial fish hatcheries - hydropower dams have contributed significantly. The causes for these declines and the best strategies for restoring these important fisheries are currently the subject of a major public policy debate.

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3.19 Hydropower projects can impede the natural flow of sedimentsFlowing water transports sediment. When the flow velocities are reduced in an impoundment, sediment drops out and collects on river and reservoir bottoms, where it can affect habitat for fish spawning. The loss of sediment downstream can degrade in stream habitat and cause the loss of beach at the mouth of the river. The deposited sediment also may contain chemical or industrial residues from upstream sources. Dams may block and concentrate contaminated sediment in the impoundment. Dredging is used in some cases, though it is costly and may raise questions regarding disposal of the dredged material. Various flushing and piping techniques are available for moving non-contaminated sediment downstream.

3.20 How can consumer electricity choice address water use and consumption?By re-directing their electricity dollars to support environmentally benign energy resources, consumers are empowered, in states that offer supply choice, to influence the existing generating resources that are deployed to meet demand. They can also support the construction of new and cleaner electricity resources that will be built to meet overall growth in demand in the future. By supporting these power options, consumers can minimize many water use and consumption impacts. Still, it should be noted that directing one's dollars to cleaner power products in no way helps premeditate damages that already have occurred. Consumers can stop the construction of new hydropower facilities or alter conditions of sitting and operation, but they cannot undo previous environmental degradation that occurred at existing hydropower facilities. Ocean wave energy can be captured directly from surface waves. Blowing wind and pressure fluctuations below the surface are the main reasons for causing waves. But consistency of waves differs from one area of ocean to another. Some regions of oceans receive waves with enough uniformity and force. Ocean waves contain tremendous energy. Currently scientists and companies are considering exploiting the wave power of oceans to harness clean and green energy.

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CHAPTER NUMBER

4

HYDEL POWER GENERATION IN USA

4.1 Studying Sea Waves with Radar

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Off shore wind is steady and blows harder. If a country is densely populated it is hard to find open space to install wind farms. That is why there are more and more offshore wind farms in densely populated Europe where there is limited space on land and relatively large offshore areas with shallow water. Scientists of the Geesthacht GKSS Research Centre are interested in offshore winds and mechanics of sea waves. They are working on a radar system to study the behavior of the sea waves. This technology will be available for utilization on the North Sea on the FINO3 research platform. This technology will help in finding out the details of the interactions between offshore wind power machines and swells.

4.2 Harnessing Tidal Wave Energy with PusPlates

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The Theme of Concept: Theme of concept is to harness the kinetic energy within the flow of water without using the conventional methods like water wheel or other types of turbines. With some changes this can be a source of producing clean energy from tidal waves.

4.3 Hydrokinetic Power Barges

Interest in hydrokinetic energy -- which generates power by using submerged or partially submerged turbines that harness the energy from flowing water -- is on the rise throughout the world. Renewable energy advocates, governments and investors are increasingly becoming aware of river currents and the huge associated energy potential. Because hydrokinetic power generation relies simply on the extraction of energy from the natural velocity of water, these power systems can be placed into sources of flowing water with minimal infrastructure or environmental impacts. Scroll down for images.

4.4 Obama Stresses Clean Energy on Earth DayPresident Barrack Obama is known as a staunch supporter of green energy. His stimulus plan has raised new hope for the environmentalists and economists alike. On the occasion of Earth Day, President Obama declared that developing renewable energy is crucial to America's prosperity. He also declared that his administration will for the first time lease federal waters for projects to generate

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electricity from wind as well as from ocean currents and other renewable sources. Obama also emphasized the need for action on global warming and preserving vast and beautiful natural resources of USA.

4.5 Renewable Energy from Slow Water Currents

We can use slow moving ocean and river waves for a new, reliable and affordable alternative energy source. A University of Michigan engineer has developed a device that acts like a fish that turns the potentially destructive vibrations in water into clean, renewable energy. This machine is named as VIVACE (Vortex Induced Vibrations for Aquatic Clean Energy). It is the first known device that could draw energy from most water currents around the world, according to a statement from the University of Michigan. "There won't be one solution for the world's energy needs," VIVACE developer Michael Baristas, a professor at the U-M department of naval architecture and marine engineering, said in the statement. "But if we could harness 0.1 percent of the energy in the ocean, we could support the energy needs of 15 billion people."

4.6 Agucadoura Generating Power for 1,500 Homes

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As the conventional sources of energy are dwindling, scientists are continuously looking for alternative sources of energy. We are frequently reading about generation of alternative and clean energy from unconventional sources. Portugal built Agucadoura, the world's first wave farm off its coast. This wave farm has three Wave Energy Converters which are producing a total of 2.25MW.

4.7 European Marine Energy to Test Tidal Power

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The European Marine Energy Centre (EMEC) site is going to be the place where marine energy farm Aquamarine Power is going to become the first Scottish company to test both wave and tidal technologies. Aquamarine Power has reached an agreement with EMEC to place its tidal stream power device known as Neptune at the test site on the Isle of Eddy. Neptune is an Edinburgh-based company.

4.8 Clean Energy from Flowing Waters

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The flowing waters in the rivers and tidal waves can be a good source of alternative energy. With 70% of the earth's surface covered with water, a great amount of energy can be produced by placing turbines at strategic locations under strong currents. This method of generating electric power is called hydrokinetic power generation. In fact, plans are under way to install 875 submerged turbines inside the Niagara River.

4.9 SeaGen Gets Ready To Go

Paul Taylor: World’s first commercial-scale tidal stream turbine set to be installed. Bristol-based Marine Current Turbines (MCT) is set to deploy its 1.2MW SeaGen Tidal System in Stanford Narrows, Northern Ireland on Easter Monday. Producing enough clean energy for 1000 homes (when fully operational), this will be the first, commercial scale, tidal stream turbine installed and operating anywhere in the world. It will generate one of the most environmentally-friendly

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forms of energy - it makes no noise, is almost completely below the surface, never runs out and has zero emissions.

4.10 Hydro-Hydraulic Energy Inventions

Pakistan inventor Sarfraz Ahmad Khan has been working hard to develop new hydro technologies like this hydro power invention. His latest concept features the run of river active setup of micro hydro power generation blended with basic principals of hydraulics. This concept explores the possibility of transmitting the (collective) mechanical power gained from run-of-river hydro setup by converting it into hydraulic pressure. The sum-up of hydraulic pressure will make the main generators work. The basic concept requires hydraulic systems that can help to us to gain some reasonably good mechanical advantages. The hydro-mechanics will convert the mechanical force into hydraulic pressure. The collective hydraulic pressure shall be utilized to rotate the generator shaft.

4.11 Seagen Tidal Power Installation

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Paul Taylor: Installation Of The World's First Commercial Tidal Current Power System Confirmed. Marine Current Turbines has today (June 6th 2007) confirmed that installation of its SeaGen commercial tidal energy system will commence during the week of August 20th in Northern Ireland's Stanford Laugh. At 1.2MW capacity, SeaGen will be the world's largest ever tidal current device by a significant margin, and will generate clean and sustainable electricity for approximately 1000 homes. It is also a world first in being a prototype for commercial technology to be replicated on a large scale over the next few years.

4.12 Hydro Power Invention

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A new hydro power technology is being developed by Sarfraz Ahmad Khan of Pakistan. In theory these hydro plants would not require a reservoir and would have a minimal impact on the environment. They could be run side-by-side in rows and would be much cheaper to build, operate and maintain. Sarfraz has high hopes that his ideas could revolutionize hydro power in his country and across the globe. He is currently seeking expert confirmation of his ideas; this article provides a brief summary of his ideas along with some of the 3D images he has created. You can help him by leaving your comments at the bottom of the page, or by joining the discussion that inspired this article.

4.13 Wave Power in Scotland

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The development of the first sub sea commercial wave farm by a Scottish company took another important step forward today (Tuesday February 20th 2007) with news that Scottish wave energy company, AWS Ocean Energy Ltd. based in Alness, Ross-shire, has secured £2.128 million funding from the Scottish Executive. The funds will be used to develop and commercialize AWS' Archimedes Wave Swing, one of the few proven technologies worldwide for generating clean, renewable electricity from the ocean's waves. The support for AWS is part of a £13 million support package for Scottish marine energy developers funded by the Scottish Executive, which aims to establish Scotland as a world leader in marine energy.

4.14 Ocean Renewable Energy Coalition

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The Ocean Renewable Energy Coalition (OREC) was founded in 2005 by Sean O'Neill (founder of Symmetrix) and Carolyn Elefant (Law Offices of Carolyn Elefant). The mission of OREC is the advancement and commercialization of offshore renewables, including offshore wind, ocean wave, OTEC and ocean and stream based tidal and current (hydrokinetic) technologies. In 2006 OREC lobbied for federal funding for offshore renewable projects and tax incentives to stimulate private investment.

4.15 Hydel Power and Poverty Alleviation

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Harnessing hydel energy can be an effective way of reducing poverty. China and India have already done that successfully. It is not a fruitful idea to keep discussing as to how much the number of people living below the poverty line has come down during the last five years. Considering that even with the reduced percentage, those suffering from acute poverty are still too many to be left on their own. Now is the time to move on and discuss the best strategy to reduce poverty and help the economy grow at the same time. Article submitted by Arshad H Abase.

4.16 Ocean Energy BionicsBioPower Systems is developing a new ocean energy technology in Australia that will use bionics to mimic natural systems in order to produce energy. Both bio STREAM and bio WAVE technologies use biomimicry, which refers to the adaptation of biological traits in engineered systems. Bio Power Systems has copied many of the beneficial traits from natural systems in the development of the new ocean energy conversion systems. The company is researching this new technology for application. Laboratory testing will be completed in 2007, and full-scale ocean-based prototypes will be tested in 2008. Commercial units are expected to reach the market by the end of 2009.

4.17Tidal Energy Industry Boom

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Small tidal power companies are taking advantage of the rising interest in alternative energies. Large amounts of coastal waters are being reserved on both coasts of North America by small companies who plan to take advantage of ocean energy technologies, in the hopes that these sites will become profitable sources of electricity. Celeste Miller, spokeswoman for the Federal Energy Regulatory Commission, says that interest in tidal power technology began about two years ago. Her agency issues permits that give companies exclusive rights to study the tidal sites. Permit holders usually have first dibs on development licenses

4.18 Pelamis Offshore Wave Energy in Portugal

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A Portuguese energy company called Enersis is funding a commercial wave energy project in Northern Portugal. Construction will begin at the end of October 2006. The project will use Pelamis wave generator technology (manufactured by Ocean Power Delivery) to harness energy from the ocean. After two decades of research and testing at the Lisbon Technical Institute, the first stage of this ocean energy project is intended to produce 2.25 megawatts and power homes through the nation's state-run electrical grid system. Ocean Power Delivery is considered to be the world's leading ocean energy company.

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CHAPTER NUMBER

5

Micro Hydro Power - Process and Controls

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Small-scale micro hydro power is both an efficient and reliable form of energy, most of the time. However, there are certain disadvantages that should be considered before constructing a small hydro power system. It is crucial to have a grasp of the potential energy benefits as well as the limitations of hydro technology. There are some common misconceptions about micro-hydro power that need to be addressed. With the right research and skills, micro hydro can be an excellent method of harnessing renewable energy from small streams. This article will attempt to outline some of the advantages and disadvantages of small scale water turbines.

Ocean wave energy can be captured directly from surface waves. Blowing wind and pressure fluctuations below the surface are the main reasons for causing waves. But consistency of waves differs from one area of ocean to another. Some regions of oceans receive waves with enough uniformity and force. Ocean waves contain tremendous energy. Currently scientists and companies are considering exploiting the wave power of oceans to harness clean and green

energy

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5.1 Introduction to Micro-hydro

Micro-hydro power was the mainstay of power generation for hundred's of years before the advent of fossil fuels and could well is again now that the problems of climate change are becoming ever more apparent. The UK has thousands of old mill sites waiting to be re-activated using modern micro-hydro water turbines rather than water wheels, and Siegen has the knowledge and experience to help make that a reality.Siegen is one of the UK's leading installers of micro-hydro water turbines and Siegen’s knowledge is second to none and we have many working systems to prove it. Please read our Introduction to Micro-hydro page which will give you an overview of what a micro-hydro system is.

5.2 Feasibility studySiegen can assist with all aspects of a micro-hydro system; A feasibility study to establish if a site it suitable for a micro-hydro system and generate an outline budget and expected energy generation. Applications for an abstraction license to the Environment Agency to obtain permission to use the water flow for micro generation. Siegen can provide a compete service for all aspects of a micro-hydro system design. Project management of all stages of the installation and commissioning of a project.

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Siegen also design and manufacture our own low head water turbines.If you wish further information then please review carefully our Estimating Head and Flow guide and then use our Hydro Enquiry form.

5.3 Alternative energyFor sustainable development we must keep attention on energy. Other vice the villagers in remote villages consume a lot of firewood, coercing oil, Dry sells etc. For that they have to spend a lot of money and it can make a lot of disturbers to family in economically, physically (Health) and socially. Hoed helps to decrease this problem.

HEDO promote;5.3.1 Micro hydropower5.3.2 Pico hydropower5.3.3 Effective stoves5.3.4 Bio-Gas plantsAnd HEDO has the skill and capacity to promote Dendro power plants and wind mill also

5.3.1 Micro Hydropower

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Daraniyagala which is HE Do’s working area is remote area in Sri Lanka. In Daraniyagala more than 50% of populations are live in off grid aria. This area is hill area with beautiful streams. The streams that flow through hill area have potential to generate energy. HEDO started promote micro – hydro power generation projects in the villages who’s having the suitable water sources in the living area. This power plant can produce enough energy to a small village for lighting their house. HEDO started this with a World Bank funded project called Energy service delivery project (ESD) in 2001.The program is very successful and HEDO staff got training about micro hydro power project designing & developing. After the training HEDO started implement power plant in 2001. HEDO has completed & facilitated several plants in the area. One of those projects selected to vote for success 10 project of UNDP/SGP. Because of this 560 house holders consume the electricity. These families are being stopped the coercion consumption almost 8400 liters and save one million Sri Lankan rupees per month. It helps to poverty reduction in villages and helps to improve their lifestyle. The communication facility, Information technology and educational capacities also improved by this.

5.3.2 Pico hydro power

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HEDO are being introduced Pico hydro power with Practical action Sri Lanka in 2008. It can generate hydro power from small scale water flow. It’s suitable whose don’t have enough water resources to develop micro hydro plant. It can generate electricity for one house or five families to get electricity for lighting. HEDO is has a target to stabilized Pico plants more than 300 within next tow years in Sri Lanka.

5.3.3 Effective stovesIn Sri Lanka most of the villagers still consume wood as a fuel. While cook foods using firewood the smoke can be caused to lungs damages. In addition to that unlimited fire wood consumption can make bad effect on forest conservation. There for ineffective stove can make bad impact for both the human and environmental. There for HEDO promotes effective stoves among villagers in the working area. It can be save wood 60% and the smoke density is very low.

5.4.4 Bio-Gas plants

HEDO promote Bio-Gas plant for both energy and manure. The Bio-Gas plant can generate enough gas for cooking purpose and save firewood consumption. Bio-Gas plant works as an organic manure production unite also. It can reduced

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chemical fertilizer consume and save the money. Bio-Gas plant is good option which is able to protect environment & improve life style of the family.

CHAPTER NUMBER

6Different Types of Dames

6.1. Mangla Dam

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Mangla Dam Project was actually conceived in 1950's as a multipurpose project to be constructed at a place called Mangla on river Jhelum located about 30 km upstream of Jhelum city (120 km from Capital Islamabad). The initial investigation and its feasibility studies were completed in 1958. Later on the project was included in the Indus Basin Project.

The construction of Mangla Dam was started in 1962 and completed in 1967.

Mangla Dam

Type Earth-fill

Max. Height(above core trench) 454 ft. 138.38 meters

Max. Height(above river bed) 380 ft. 115.57 meters

Crest Elevation 1234 ft. SPD 376.12 meters

Length of Crest 11000 ft. 3353 meters

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Besides providing timely irrigation supplies to agriculture, the project has generated 174.067 Billion units of low cost hydel energy since its commissioning. Annual Generation during 2006-2007 was 6.150 Billion KWh while the Station shared 1150 MW peak load which was 8.51% of total WAPDA System Peak.

6.2. PURPOSE OF THE PROJECTMangla Dam is a multipurpose project primarily meant for affecting part replacement of water supplies of three eastern rivers from Jhelum river. Besides, it is designed to conserve and control flood water of river Jhelum through significant reduction in flood peaks and volumes at downstream by incidental use of the available storage space. The other by products are power generation to meet the power demand of the country, fish culture to provide protein rich diet, tourism to provide healthy recreation facilities to the people and navigation.

6.3. PROJECT COMPONENTSThe project consists of two dams (Main Dam & Jeri Dam), two dykes to contain reservoir, two spillways for outflow regulations, intake structures with five tunnels, a power house and a tailrace canal.

6.4. POWER HOUSEPower House has been constructed at the toe of intake embankment at the ground surface elevation of 865 ft. SPD. The water to power house is supplied through five steel lined tunnels of 30/26 ft. diameter. Each tunnel is designed to feed two generating units. The power house tailrace discharges into New Bong Canal which has a length of 25,000 ft. with discharge capacity of about 49,000 cusecs, and terminates at an automatic gate control headworks at about 12 km downstream located near old Bong Escape Headwork’s.

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Power Station was completed in four stages. The initial phase comprising of four units of 100 MW each was completed in 1967~1969. The first extension of Units 5~6 (2 x 100 MW) was completed in 1974 while second extension comprising of Units 7~8 (2 x 100 MW) was completed in 1981. The project attained its maximum capacity of 1000 MW with the final extension of Units 9~10 (2 x 100 MW) in 1993/94.

During the high reservoir level period, Mangla is able to generate 1150 MW against the rated capacity of 1000 MW due to permissible overloading of 15% whereas the capacity reduces to about 500 MW in the lean flow period (winter season) due to low reservoir level.

Salient features of various components of Mangla Dam and Power House are as under:

6.5. Tarbela Dam

Tarbela Dam is one of the world’s largest earth and rock filled Dam and greatest water resources development project which was completed in 1976 as a component part of Indus Basin Project. The Dam is built on one of the World’s largest rivers – the Indus known as the “Abbasin” or the father of rivers.

Emerging from the znd of glaciers on the northern slopes of Kailash ranges, some 17,000 feet (5182 meters) above sea level, the river Indus has its source near the Lake Mansrowar in the Himalyan catchment area. It flows over 1800 miles (2900 k. meters) before it outfalls into the Arabian sea draining an area of about 372,000 square miles (964,261 sq.kms).

The World Bank accepted Tarbela Dam Project as a part of the Settlement (Replacement) Plan under Indus water treaty in 1965. WAPDA was entrusted

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With its execution on behalf of the Government of Pakistan. HARZA ENGINEERING COMPANY International, who was the General Consultants of WAPDA, carried out the review studies of the Project. In February, 1960 Tippetts – Abbett -  McCarthy – Stratton of USA commonly known as TAMS were appointed the Project Consultants, and were entrusted with the task of investigation, preparation of detailed designs, and contract documents for the project and also the supervision of construction work during its execution.

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6.6. The Project – Main Features

The Project consists of a 9,000 (2,743 meters) long, 465 feet (143 meters) high (above the river bed) earth and rock fill embankment across the entire width of the river with two spillways cutting through the left bank discharging into a side valley. Its main spillway has a discharge capacity of 650,000 cusecs (18,406 cumecs) and auxiliary spillway 850,000 cusecs (24,070 cusecs). Two auxiliary embankment dams close the gaps in the left bank valley. A group of 4 tunnels (each half a mile long), through the right abutment rock have been constructed for irrigation releases and power generation. During the construction operations, these tunnels were used initially for river diversion. Irrigation tunnel 5 situated on the left bank, for which NESPAK were the Project Consultants, was put into operation in April 1976.

A power station on the right bank near the toe of the main dam houses fourteen (14), power units, 4 units, each with installed generating capacity of 175 MW are installed on tunnel 1, 6 units (NO.5 to 10), 175 MW each on tunnel NO.2 and 4

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Units ( NO.11-14)  of 432 MW each on Tunnel 3, thus making  total generating capacity of Tarbela Power Station as 3478 MW.

The reservoir is 50 miles (80.5 km) long 100 square, miles (260 square kilometers) in area and has a gross storage capacity of 11.6 MAF (17.109 million cu. Meters) with a live  storage capacity of 9.7 MAF (14,307 million cu. Meters). The total catchment area above Tarbela is spread over 65,000 sq. miles (168,000 sq. kilometers) which largely brings in snowmelt supplied in addition to some monsoon rains. Two main upstream tributaries join the Indus river, Shyok river at an elevation of 8,000 ft. (2438 meters) above seal level near skardu and Siran river just north of Tarbela.

6.7 Main DamThe principal element of the project is an embankment 9,000 feet (2743 meters) long with a maximum height of 465 feet (143 meters). The total volume of earth and rock used for the project is approximately 200 million cubic yards (152.8 million cu. Meters) which makes it the largest man made structure in the world, except for the Great Chinese Wall which consumed somewhat more material. The main embankment is a carefully designed, zoned structure composed of impervious core, bounded on both sides by gradually increasing sized material including coarser sands gravels cobbles and finally large sized riprap on the outer slopes. An impervious blanket, 42 feet (12.8 meters) thick at the dam and tailing to 5 feet (1.52 meters) at the upstream end, covers 5,700 feet (1737 meters) of the alluvial foundation on the upstream side. These deposits in the valley are up to 700 feet (213 meters) deep and in places consist of open work gravels. The dam crosses this essentially alluvial valley and connects the last points to high ground before the mountains give way to the plains. A 24 feet (7.32 meters) thick filter drain mattress under the embankment together with nearly vertical chimney drain provides the necessary facility to collect the seepage.

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6.8 Auxiliary Dams

The auxiliary dams resembling the main embankment dam in design close the gaps in the left periphery of reservoir. The smaller of the two auxiliary dams, however, has a vertical core extending down to the underlying rock, and the larger auxiliary dam has a short upstream blanket terminating in a cut off to rock.

6.9 SpillwaysOn the left bank, two spillways discharge into a side channel. The total spillway capacity is 1,500,000 cusecs (42,476 cumecs) which constitutes the peak outflow resulting   from routing the probable maximum flood. The service spillway having 44 percent of the total capacity is sufficient to pass all but very rare floods. Its maximum discharge capacity is 650,000 cusecs (18, 406 cumecs).

The auxiliary spillway is similar in design to the service spillway. It has nine radial gates with crest elevation of 1492 feet (455 meters) and flip bucket at elevation 1220 feet (372 meters) A longitudinal drainage gallery along with a network of drainage pipes under the channel and the head works has been provided to release pore water pressure in both the spillway foundations.

6.10 Reservoir

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The 50-miles (81 kilometers) long reservoir created by the Project has a gross storage capacity of 11.6 million acre feet (MAF) (17,109 m.cu. meters) at the maximum lake elevation of 1550 feet (472 meters) a residual capacity   of 1.9 MAF (2,802 m cu. Meters) at the assumed level of maximum drawdown elevation 1300 feet (396 meters) and a net usable capacity of 9.7 MAF (14,307 m cu. Meters). The Tarbelareservoir stores water during the summer months of June, July and August when water either causes disaster by flooding in the surrounding areas or goes waste into the sea. It is to be noted that more dams can be constructed on Indus since its annual flow is substantially more than is being stored at present. Kalabagh Dam on River Indus is in its advanced stages of design, while investigations are underway for the upstream Basha Dam.

6.11 TunnelsThe four, each of half mile long, tunnels through the right (rock) abutment initially served for the diversion of water during the final phases of construction of the Project. Now they are being used for Power generation (tunnels 1, 2, 3 and eventually 4). The discharge capacity of each irrigation tunnel at higher reservoir elevations is approximately 90,000 cusecs (2,549 cumecs). The discharge pass through energy dissipator structures and the water returns to the river. A fifth tunnel on the left bank designed to augment irrigation releases up to 80,000 cusecs (2,265 cumecs) at high reservoir level, has also been added to the project.Power Station

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6.12 Tarbela Power Station

According to the original plan, four (4) power units of 175 MW generating capacity each were to be installed on each of the tunnels 1, 2 and 3 located on the right bank with the ultimate installed capacity of 21,00 MW. Of these, four (4) units on tunnel 1 were commissioned in the year 1977. Due to increasing prices of the fossil fuel, the Govt of Pakistan has been laying greater emphasis on generation of cheap Hydel power. In pursuance of this policy, WAPDA carried out studies to tap the maximum power potential of Tarbela. As a result, it has been found possible to install six (6) units, instead of four (4) only on tunnel NO.2. Units 5 to 8 on tunnel NO.2 were commissioned in 1982, and units 9 and 10 in 1985. Based on studies, four power units of 432 MW capacities each were installed on tunnel NO.3. Thus the total ultimate power potential of the project enhanced from 2100 MW as originally planned to 3478 MW.

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6.12.1 Project ImplementationOn May 14, 1968, the World’s largest single contract for the construction of civil works of the Tarbela Dam Project was signed at a price  of RS.2,965,493,217 ($ 623 Million) between the Water and Power Development Authority and the Tarbela Dam Joint Venture which comprised a group of three Italian and three French heavy construction contractors. Later five German and two Swiss contractors also joined the group making up a consortium of thirteen European firms led by Italian firm namely Impregilo.

The construction of Tarbela Dam was carried out in three stages to meet the diversion requirements of the river. In stage-I, the river Indus was allowed to flow in its natural channel while work was continued on right bank where a 1500 feet (457 meters) long and 694 feet (212 meters) wide diversion channel was excavated and a 105 feet (32 meters) high buttress dam was constructed with its top elevation at 1, 187 feet (362 meters) The diversion channel was capable of discharging 750,000 cusecs (21,238 cumecs). Construction under stage-I lasted 2½ years.

In stage-II, the main embankment dam and the upstream blanket were constructed across the main valley of the river Indus while water remained diverted through the diversion channel. By the end of stage-II, tunnels had been built for diversion purposes. The stage-II construction took 3 years to complete. Under stage-III, the work was carried out on the closure of diversion channel and construction of the dam in that portion while the river was made to flow through diversion tunnels. The remaining portion of upstream blanket and the main dam at higher levels was also completed as a part of stage-III works.

Type Earth & Rock fill  Max. Height    (above river bed) 465 ft. (147.82 meters)Crest elevation 1565 ft. SPD (477 meters)Length of Crest  (Main dam) 9000 ft. (2743 meters)

Reservoir

Length 60 miles (97 km)Max. depth 450 ft. (137 m)Area 60000 acres (100 square miles)Max. conservation 1550 ft. SPDA (472.45 meters)Min Operation level 1300 ft SPD (396.25 meters)Design Gross Storage 11.3 MAF  Existing Gross storage 9.00 MAF  Design live storage 9.68 MAF Existing live storage    At 1365 ft SPD 7.3 MAF  Surface Area 100 sq miles (259 sq km)

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6.12.2 Project BenefitsIn addition to fulfilling primary purpose of the Dam i.e. supplying water for Irrigation, Tarbela Power Station has generated 341.139 Billion KWh of cheap hydel energy since commissioning. A record annual generation of 16.463 Billion KWh was recorded during 1998~99. Annual generation during 2007~08 was 14.959 Billion KWh while the Station shared peak load of 3702 MW during the year which was 23.057% of total WAPDA System Peak.

6.13 WARSAK DAMWarsak Hydro Electric Power Project is located on River Kabul at about 30 km from Peshawar in North-West Frontier Province of Pakistan. The project financed by Canadian Government was completed under COLOMBO PLAN in two phases. In general, the project consists of a mass concrete gravity dam with integral spillway, power tunnel, power station, a concrete lined 10 feet diameter irrigation tunnel on right bank and a 3 feet diameter steel pipe irrigation conduit on the left bank of the reservoir. The 250 ft. high and 460 ft. long dam with reservoir of 4 square miles had a live storage capacity of 25,300 acre-feet of water for irrigation of 119,000 acres of land and meeting power generation requirement. A spillway with nine gates is capable to discharge 540,000 cusecs of flood water.

6.14 POWER STATIONThe first phase including construction of Dam, Irrigation tunnel, civil works for Phase-II and installation of four units each of 40 MW capacities with 132 kV transmission systems, was completed in 1960 at a total cost of Rs.394.98 million. Two additional generating units each of 41.48 MW capacities were added in 1980-81 at a cost of Rs.106.25 million as second phase of the project.

Warsak Dam has now completely silted up and practically there is no available storage. Power generation is being achieved according to water inflows in River Kabul like a "Run-of-the-River' project. Lean flow period at Warsak is observed from October to March during which capability reduces to about 100 MW (Peak).

Salient features of main components of Warsak Dam and Power House are as under:

Warsak Dam

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Type Mass Concrete Gravity Dam

Height 250 ft. 76.20 meters

Length 460 ft. 140.21 meters

Reservoir

Max. Conservation Level 1270 ft. SPD 387.10 meter

Design Live Storage 25300 AF

Existing Live Storage Nil

Surface Area 4.0 sq. miles 10.36 sq. km

Project BenefitsBesides providing irrigation water from the dam during early years of its life, the project has generated over 34.217 Billion KWh of cheap energy since its commissioning. Annual generation during 2006~2007 was 1035.375 Million KWh while the station shared 218 MW peak load.

6.15 WARSAK REHABILITATION PROJECT

6.15.1 GeneralWarsak Power Station attained its ultimate capacity of 243 MW in 1981. With the passage of time, this capacity reduced to 150 MW due to following reasons:

Structural deformation of Power House. Rapid erosion in the hydraulic equipment due to excessive and abrasive

natured silt carried in River Kabul.

These operating conditions necessitated a comprehensive plan for rehabilitation of Warsak.

6.15.2 Project ObjectivesA Rehabilitation Project was planned with the assistance of Canadian Government having following objectives:

To restore full generating capacity of Warsak Power Station.

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To prolong useful life of the project by another 30 to 40 years by rectifying various problems of civil structures and electrical & mechanical equipment.

6.15.3ScopeReplacement of Power House Overhead Crane, modification of Butterfly Valves of the Units complete refurbishing/major overhauling of all the units, providing new Trash Racks and Semi Automatic Trash Rack Cleaning Machine, repair of Embedded Guides for Draft Tube Gates, repair of Spillway Gates and Sill Beams, repair of Power House Roof, Floors and Walls, replacement of old 132 kV Circuit Breakers with SF-6 Breakers.

6.16 Chashma Hydropower Project

Chashma Hydropower Project is located on the right abutment of Chashma Barrage. The barrage is located on the Indus River near the village Chashma in Mianwali District, about 304 k.m. North West of Lahore. The project has been estimated at Rs17, 821.77 million including foreign exchange component of Rs 9264.25 million. The installed capacity of power Station is 184 MW comprising of 8 bulb type turbine units each of 23 MW capacities. The bulb turbines have been installed for

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the first time in Pakistan. The first unit was commissioned in January 2001, while final commissioning of all units was completed in July 2001.

6.16.1 ReservoirMaximum pond level 649 ft.

Normal pond level 642 ft.

Minimum pond level 637 ft.

6.16.2 Project BenefitsThe expected total energy generated annually after commissioning of all eight units, is estimated at 1081 GWH. Based on the energy generated, the estimated yearly revenue is RS2259.29 million.

Start Your Virtual Tour:

Intake Gates Power House Turbine Floor Control Room Switch Yard Fishery

6.16.3 Intake GatesGiant intake gates allow the river to pass through the dam. They are each 17 feet wide and 39 feet high. Due to the extreme variations in water levels (especially during the spring thaw) 10 flood gates, known as "sluice gates", were added so that excess water could pass through the dam quickly. These sluice gates allow a maximum discharge of 16,100 cubic meters of water per second. The highest flow of the St. John River ever recorded at Mactaquac was 12,200 cubic meters per second.

6.16.4 Power HouseThe power house, containing the turbines and generators, is 183 meters long and 25 meters wide. Water coming through the intake gates flows down a pipe known as a "penstock" until it reaches the turbines. The force of the water spins

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a giant rotor blade at the end of the turbine. The rotor blades act like a giant propeller and convert the force of the water into mechanical energy. The spinning of the rotor blades turns a shaft that runs through a generator where the mechanical energy is converted into electricity.

6.16.5 Turbine FloorInside the main turbine hall are six Kaplan turbines capable of generating 672 MW of electricity. The first turbine was installed in 1968 when the Mactaquac Generating Station went online, and the newest was activated in 1980. In its simplest form, the generator consists of a magnet rotating inside a wire coil. This creates alternating currents in the stator winding and results in electricity. At the Mactaquac Generating Station, the massive generators function in the same way.

6.16.6 Control RoomThe Control Operator manages the flow of water through the dam and the generation of electricity. The operator works in the main control room located in the power house. All of NB Power's hydro generating stations, except Milltown use a computer-based supervisory control and data acquisition similar to the system located at the Mactaquac Generating Station.

6.16.7 Switch YardThe electricity produced by the generator travels to the switchyard where it is stepped up from 13,800 volts to 138,000 volts. This high voltage is required to transmit the electricity to communities a great distance away. The electricity travels over high voltage transmission lines to a substation where it is broken down into smaller voltage for distribution to customers

6.16.8 FisheryNB Power recognizes the importance of our Atlantic salmon and has incorporated special features into the dam design. The salmon arrive at the dam on their up-river spawning in mid-June and are attracted to special weir gates located near the base of the dam. Salmon enter the weir gates at the base of the dam and encounter an artificial current flowing through a channel inside the dam structure. This leads to a hopper pond from which the fish are transported by truck upstream so they can continue their migration. From the tailrace deck, visitors can watch fish being transported upriver beyond the dam.

6.17 SAFETYAt NB Power, the safety of our customers and employees is our highest priority. That's why, in addition to our own safety programs; we're joining forces with other community organizations to educate New Brunswickers about electricity.

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We're doing this because we understand that the unsafe use of electricity can be deadly. By working together and reaching out to people in the workplace, home, and everywhere they come into contact with electricity, we know we can dispel myths, promote better understanding and help prevent electrical accidents, injuries and death. Using the navigation to the right, you can learn about myths about electricity, how to prevent electrical accidents and how to respond if there is an electrical emergency.

6.18 School Programs In co-operation with concerned educators and working with our customers, we've developed a safety awareness campaign to help educate and protect New Brunswick children. Specially trained members of the NB Power team are available to visit classrooms across the province with targeted presentations that promote understanding and minimize the risk of electrical contact injury.We also offer free educational materials to teachers and students. If you are a New Brunswick teacher and interested in having a safety presentation for your class.

6.19 Safety Presentations Workplace safety – for our own employees and others who work around power lines – is our most important job. As part of our ongoing program to promote electrical safety and reduce the risk of accidents, we conduct free seminars upon request.

6.20 Erik Matchett - Public SafetyMore Workplace Safety InformationFor more information on how to keep you and your loved ones healthy and safe, and what to do in case of a workplace injury or illness.

6.21 LearningLearning about electricity is fun – at least we think so at NB Power! We're committed to lifelong learning and we hope you enjoy learning more about New Brunswick 's power supply. That's why we've created our learning section for

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anyone who is interested in learning about electricity, the sorts of generation used in New Brunswick and general facts about the power that keeps the energy flowing to New Brunswick.

6.22 Learn About Electricity When we turn on a light switch or an appliance, we often don't think about what is happening to bring that electricity to us. Since the early discoveries in the 1800's it has been taken for granted that when you get up in the morning, you will have electricity to run the pump to provide water, listen to the radio, watch TV and of course check your email. The word electricity came from the Greek word elektron, meaning amber. Several centuries ago it was noticed that when you rubbed amber stone things "stuck" to it. This was the beginning of the discovery of electricity in itsSimplest form - static electricity.

In 1800 Alessandro Volta made the first electric cell - an electric cell converts chemical energy into electrical energy. About 30 years later Michael Faraday made the first electric generator.Electricity is electrons in motion. Every atom has three basic parts - electrons, protons and neutrons. An electron carries a tiny negative charge. Electricity occurs in nature in the form of lightning, electric eels and the small shock you sometimes feel when you touch a doorknob, particularly in the winter.To get electrons moving so we can turn on lights and run factories, we build power plants where magnets are spun inside coils of wire. The spinning magnets put electrons in motion inside the wires, creating electricity. This is called a generator. No matter what method is used to turn the magnets, the electricity produced by the generator is the same.

6.23 There are two major categories of energy resources: Renewable, which means the resource can be used over and over again. Examples of renewable energy resources are wind, solar, and water. Non-renewable; this type of resource can be used only once. Examples of non-renewable resources are oil and coal. NB Power uses both renewable and non-renewable energy resources to supply the entire province of New Brunswick with electricity.

6.23.1 System MapAt NB Power, our focus is bringing our customers power in homes and businesses across New Brunswick. We rely on our 16 generating stations powered by hydro, coal, oil, nuclear and diesel to bring electricity to over 300,000 homes and businesses across New Brunswick.

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And work is already well underway to meet out commitment to have 400 MW of wind energy in place by 2010. The diversity of our generation system works to make sure that when you need electricity, it is there for you.

6.23.2 Vegetation Program It is NB Power’s first priority to deliver safe and reliable electricity throughout New Brunswick while ensuring that we meet or exceed environmental standards.  It is important that NB Power manage the vegetation (trees, shrubs, etc.) that grow along both transmission and distribution rights-of ways. One way to do this is through the establishment of low-growing plants along our transmission rights-of-ways.  Naturally grown forest trees growing along these lines can result in access and safety concerns for maintenance crews. Additionally, vegetation that grows into or falls onto power lines can ultimately lead to power outages and even forest fires.  Entire communities can loose power as a result of a transmission outage.  Losing power is more than a mere inconvenience – it is costly and can endanger life. 

6.24 What does NB Power do to control vegetation and why?Vegetation, such as trees, that come in contact with power lines account for more than 50% of power outages in Canada.  Many types of vegetation, including maple, birch and poplar trees, grow under transmission lines along rights-of-ways.  If left unmanaged, these trees will grow into the power lines or could fall onto lines and can cause outages.  Uncontrolled growth can also create fire and safety hazards and hinder routine power line maintenance.  It can also make restoration efforts hazardous and difficult.As well as potentially causing power outages, trees growing into power lines can conduct electricity and are potentially a serious safety hazard to the public and our maintenance and restoration crews.   To reduce all of these risks, NB Power uses a variety of methods to control vegetation.  In fact we use an Integrated Vegetation Management Program.

6.25 What is an Integrated Vegetation Management Program (IVMP)?NB Power employs an IVMP, which includes using a range of methods to control vegetation, such as hand-cutting, mechanical cutting, pruning, mowing, and Health Canada approved herbicide applications  Alone or in combination, NB Power takes care to ensure that the right method is used in the right place and at the right time.For example, while maintaining transmission lines, it is NB Power’s goal to establish and maintain low growing vegetation such as grasses, shrubs and bushes, which are compatible with the operation of the transmission system, while minimizing negative effects on the environment.

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The main steps in an IVMP are:Inventory – gather and record information on vegetation, watercourses, habitats etc. Development of management cycles - determine when to carry out the required work, based on vegetation types and growth rates. Planning – develop a site specific approach that reflects safety, reliability, and the environment as a priority. Implementation - select the right control method for each location under the supervision of our ISA Certified Arborists and Forest Technicians. Evaluation – inspect work during and after vegetation management process.

6.26 How does this affect me if I use a Transmission Right-of-way?When NB Power crews are carrying out maintenance activities in a Right-of-way your access might be limited during that work.  At all other times, you can still access and use the Right-of-way.

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CHAPTERNUMBER

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Electricity: Solutions and Ongoing ProjectsJump to Comments

7.1 History After the construction of the Hydro-Electric Tarbela Dam and the Mangla Dam, by General Ayub Khan and General 

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7.2 TarbelaYahya Khan in the 1960’s, our governments failed to conceive and initiate major electricity projects. The inept governments of PML-N and PPP, that still consider themselves vital to democratic dialogue within the provinces, failed to create dialogue within provinces, on the most important issue facing Pakistan’s energy survival – the Kalabagh Dam. Their governments failed to plan for the future growth and energy requirements. Recently the government of PPP has scraped the project altogether. 

7.3 Unexpected Economic Boom & Energy Consumption in the last 10 years Pakistan’s $75 billion economy boomed into a $160 billion economy, with the consumption of gas, electricity and coal increasing YEARLY to an average rate of 7.8 percent, 5.1 percent and 8.8 percent, respectively. The number of electricity consumers grew from 15.9 million in 2005-06 to 16.7 million in 2007, showing a growth of about 70 percent over the last 10 years. The major Energy consumption sectors of the country are: Industrial (38.3 percent), Transport (32.8 percent), Residential and Commercial (25 percent), Agriculture (2.5 percent) and others (2.2 percent). As regards Electricity, the Household sector has been the largest consumer over the last 10 years, on average consuming 44.8 percent, followed by Industrial sector (29.4 percent), Agriculture (12.2 percent), Commercial sector (5.9 percent), Street lights (10.6 percent), the officials say.

7.4 Record Sales of Electronic Items

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 Recently, we got good news from Pakistan Haier. In May, Pakistan Haier made new RECORD air-conditioner, refrigerator monthly output. The sale volume reached all time high, the year-on-year sale increase of Air-conditioner, Refrigerator, Washing machine, Micro wave and TV are 136%, 58%, 180%, 210% and 106% respectively. Similarly, many other Electronic Companies have created record sales.

7.5 Projects executed and under Construction 

The first unit of 290-megawatt of Ghazi Brotha Hydel Project (GBHP) went into operation in June 2003, and 

Hydro Power Inventioncontributed around 50mw of electricity to the national grid. Four more units were added every quarter, and by 2004 the GBHP was contributing 1,450 mw.Nuclear power plant Chashma-2, will soon come on-line, and will add another 300MW to the national grid.

7.6 Mangla Dam uprisingMangla Dam uprising will give another 644 GWh of power.Gomal Zam Dam is under final stage of construction, and upon completion it will produce 17.4MWIn 1999, our installed capacity was merely 15,860 MW. (With Hydel 4826 + Thermal 10,897 + Nuclear 137) In 2005-06, our installed capacity increased to become 20,495 MW. (With Hydel 6499 + Thermal 13,534 + Nuclear 462)

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7.7 Concrete steps under the PML-Q Government President Pervez Musharraf launched the Rs 130 billion (US 2.16 billion) Neelum-Jhelum Hydroelectric project aimed at producing 969 MW power.Work on 11 projects with an accumulative power generation capacity of more than 12,000MW would start by 2009. 

Mirani Dam inauguratedThese projects include Bunji (5,400MW), Dasu (4,000MW), Kohala (1,100MW), Spatgah and Palas Valley (1,230MW).

7.8 Wind and Solar TechnologyPakistan is seeking to explore alternative sources of energy production and use Wind and solar technologies with the aim to produce 9,700 MW wind power by 2030, thereby providing electricity to 7,874 off-grid villages in Sindh and Baluchistan.225 wind water pumping systems have been installed in Balochistan. Over 140 micro wind turbines of 500 Watts each are operational in Sindh and Balochistan, providing electricity to 691 houses in 18 remote, off-grid villages.                                                                          

7.9 Hydel Power:The government is giving top priority to Hydel power with the potential of producing 40,000 MW Power of which only 15 percent had been exploited so far.In 2001, the Water and Power Development Authority of Pakistan identified 22 sites for launching Hydropower projects to meet the ever-increasing demand for

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cheap power. It indicated that about 15,074 mw could be generated on the completion of these projects, which would also meet the water irrigation requirements for the growing agriculture sector.

7.1o Pakistan Sugar Mills:Association (PSMA) has informed the government that sugar mills can produce 2,000MW of electricity in the next five years.

7.11 Pakistan Atomic Energy Commission:(PAEC) has decided to establish an Engineering Design Organization (EDO) for the indigenous development of nuclear power plants (NPPs) in the country. The PAEC informed authorities that it was planning to add about 1,260MW through Hydel power, 880MW from Alternate energy, 4,860MW from Gas, 900MW from Coal and 160MW from Oil by 2010. The Karachi Electric Supply Corporation (KESC) is investing in a new 220-megawatt power plant that will help control the power shortages in the city, said. The plant will start generating 192MW by March and the remaining 28MW will start being distributed by December 2008.

7.12 Thar Coal:The government has decided to develop the Thar coal for power generation on a priority basis to overcome energy crisis following. Out of six various companies that inked MoU with concern authorities to establish coal power projects; two companies have started drilling work in their respective areas.Confirmed estimates that its reserves were equivalent to at least 850 Trillion Cubic Feet (TCF) of gas – about 30 times higher than Pakistan’s proven gas reserves of 28 TCF.

By using only 2% of the existing coal reserves, we can generate around 20,000 MW (20 GW) for almost 40 yearsThese estimates were confirmed by separate bankable feasibility studies conducted by Chinese and Russian experts. 185 Billion Tons of coal deposits in Pakistan were second only to 247 Billion Ton reserves in the United States and much higher than 157 and 115 Billion Ton reserves of Russia and China, respectively. Thar coal reserves were equivalent to at least 400 Billion Barrels of oil – equivalent to oil reserves of Saudi Arabia and Iran put together. One estimate puts Pakistan’s coal energy at 576 Billion Barrels of oil which is equivalent to the combined oil reserves of the 3 largest producers. The government is planning to set up 5,000-megawatt power generation facilities using coal as fuel within next few years. 

7.13 Ongoing Power Projects

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 The Ongoing Power Projects, for which allocations have been made in 2007-08 Budgets, are Mangla Dam Raising 

Project (Rs 20 billion), Mirani Dam (Rs 500 million), Sabakzai Dam (Rs 200 million), Kurram Tangi Dam (Rs 2.84 billion), Sadpara Multipurpose Dam Rs (900 million), Gomal Zam Dam (Rs 1.8 billion), the Greater Thal Canal Phase I (Rs 8.5 billion), the Greater Thal Canal Phase II (Rs 2.5 billion), construction of 20 small dams in NWFP (Rs 870 million), Bhasha/ Diamer Dam (Rs 500 million), Khan-Khawar hydro project (Rs 1.3 billion), Dubir Khawar hydro project (Rs 2.1 billion), transmission arrangements for power dispersal of Ghazi Barotha (Rs 1.67 billion) and Neelam-Jhelum hydro project (Rs 10 billion).

New projects for the next fiscal year include the Sukkur Barrage Rehabilitation and Improvement project (Rs 100 million), Akhori Dam PC I (Rs 200 million), construction of Jaban Hydroelectric Power Station and Jaban Hydroelectric Power Station (Rs 40 million).

7.14 Upcoming Immediate ProjectsThree rental power houses would start generating 1,067 megawatts of electricity by end of year 2008, respectively. Agreements had been signed with China to establish power plants at Nandipur and Chichu ki Malian, and tenders had been issued for two 500MW power plants at Dadu and Faisalabad which would be run by gas and furnace oil. An 800MW power plant would be set up at Guddu.

September 10, 2009If you're new here, you may want to subscribe to my RSS feed. Thanks for visiting!

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When it comes to large-scale alternative power, hydroelectric plants are currently the most common – supplying more than 80% of the word’s renewable energy. While hydro power is much cleaner and more cost-efficient than the generation of electricity using fossil fuels, there are a number of disadvantages including the threat of dam failures, disturbance to the natural environment, and some greenhouse gas emissions.Small hydroelectric power systems, however, create fewer threats and can be an excellent alternative energy source for residential use.  Could small-scale hydro power be a viable option for your home?  Keep reading to learn more…Small hydroelectric projects are growing in popularity in the commercial energy sector, especially in China.  These plants generally range in capacity, generating up to 10 MW of power – enough to supply a small community.  Small-scale hydro power can also be a cost-efficient alternative for residential, off-grid living under the right conditions.

7.15 Requirements for Hydroelectric Power

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To generate power with water, you’ll of course need an adequate supply of water – a flow of at least 2 gallons per minute with a substantial drop to create pressure.  A drop of just 2 feet would require a flow of 500 gallons per minute. Mother Earth News offers some useful advice on site assessment for your homestead hydropower project.You’ll also need the necessary hardware to harness the power generated by the flowing water and then convert the energy into a usable current for your home.  A hydro power generator is the heart of the system and can be purchased through a variety of suppliers.  You’ll also need a battery pack and inverter, as well as a sufficient amount of piping.  A complete hydroelectric power system will cost as little as $1000 up to as much as $10,000, depending on your needs.

7.16 DIY Hydro Power

If you’re mechanically inclined with a good supply of flowing water nearby, consider trying your hand at a homemade hydroelectric power system.  Build it Solar has a tremendous amount of resources to help with your hydro power planning and installation as well.

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For those who prefer to start with a really small-scale hydro system, check out Sam Redfield’s bucket hydro generator – the perfect alternative energy gadget charger – or this faucet powered hydro turbine made of recycled CDs and auto parts.  If a rustic waterwheel is more your style, take a look at the DIY home energy projects we mentioned in a previous post.If you’re considering an alternative source for residential power, hydroelectric may be an affordable and efficient option if you have a nearby supply of flowing water.  Be sure to look into local and state regulations regarding small hydro power systems before you get started.

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7.17 N-er-G Talks Hydroelectric Power

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7.18 Hoover Dam Tour 2009Hydro electric energy is one of the most well-known sources of power generation. While hydro electricity made up a large portion the US power supply in the 50’s and 60’s, hydro electric power generation has become less popular as fossil fuel generation became more common. Like wind, solar geothermal and more hydro electric power generation is a clean way to convert mechanical power into electricity. Most people know how hydro electric power plants work but we wanted to do a write-up on it anyway as it is an important source of electricity, especially in the western part of the US.Hydro electric power plants work by converting mechanical energy into electricity. Basically, hydro electric plants use the energy from falling water to spin turbines which are connected to electric generators. These generators send the electricity generated to transformers for increasing the voltage and distribution it to millions of consumers in the surrounding cities.Typically, hydro electric plants (dams) are built on large rivers, where they can collect water in large reservoirs. The water collected behind the dam of hydro electric plants stores potential energy. The potential energy is then converted to kinetic energy when the stored water is allowed to flow down a channel to spin a

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turbine. The kinetic energy of the water spins a turbine, which uses the kinetic energy to generate electricity.Probably the most common hydro electric power plant in the United States is Hoover Dam, located on the Colorado River, where half of the dam lies in Arizona and the other half in Nevada. The Hoover Dam supplies electricity to cities in Arizona, Nevada and Southern California. Many smaller dams on the Colorado River, downstream from the Hoover Dam, are used to generate electricity for other cities in Southern California and Mexico.There are many hydro electric power plants located all over the United States. The electricity generated by these plants is considered to be clean because virtually no emissions or pollutants are released during the energy generation process. Hydro electric energy is thought of as a sustainable energy source, although research shows that the natural water sources are drying up. The Hoover Dam reservoir measures 15 meters lower this year than in previous years. And with nuclear power generation and fossil fuel generation as competitors, hydro electricity supplies approximately 10% of the United States’ consumed energy.

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Water Energy Technologies

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8.1 HydropowerConverts kinetic energy from falling water into electricity. It never uses more water than the nature is providing. The size of hydro energy sources differs from huge artificial dams to smaller natural rivers. Small-Hydro energy meets renewable energy standards by having minimal negative environmental impacts. Comparatively, large-scale hydro sources often involve large dams that may have serious consequences on the surrounding environment. Hydropower is clean. It doesn't produce any greenhouse gases or generates any waste products that might need special handling or disposal. Besides, it is carbon-free energy.

Big hydro dams can harm the natural and ecological nature friendly.

Hydro plants take the energy that is in the water and with a simple mechanism converts it into electricity. Actually water plants are based on a simple concept:

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water that flows through the dam turns the turbine. That turbine turns a generator. The system is working as shown in picture,

8.1.1 Dam - it holds the water, thus creating a reservoir. This is considered as a stored energy.

8.1.2 Intake - together gates of a dam and the force of gravity pulls the water through the penstock - a pipeline - that leads to the turbine. The water builds up the pressure.

8.1.3 Turbine - the water turns the big blades of a turbine, which is attached to a generator above it. The most common type of turbine is Francis Turbine, which looks like a big disc with curved blades.

8.1.4 Generators - together with turning turbines blades, lots of magnets inside the generator turn as well. Giant magnets rotate past copper coils, producing alternate current (AC) by moving electrons.

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8.1.5 Transformer - inside the powerhouse a transformer takes AC and transforms it to higher voltage current.

8.1.6 Power lines - out of every power plant comes out four wires: the three phases of power being produced simultanously, plus, neutral ground common to all three.

8.1.7 Outflow - used water is carried out through tailraces - pipelines, and re-enters the river downstream.

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