Hydroelectric Power DevelopmentMember of Group :

1. Rizky Nur Fitri

(105060401111014)2. Linda Irnawati Gunawan

(105060407111002)3. Qonit Ayu Pranita

(105060401111001)4. Oksa Ega Hermawan

(105060404111001)5. Lutfianto Cahya Rachmadan(105060400111006)6. Agung Rizqi Ramadhani

(105060407111001)

Lecturer : Dr. Indah Winarni M.AWATER RESOURCES ENGINEERINGBRAWIJAYA UNIVERSITYMALANG

INTRODUCTION

Hydroelectric Power...what is it?

Its a form of energy a renewable resource. Other renewable resources include geothermal, wave power, tidal power, wind power, and solar power. Hydroelectric powerplants do not use up resources to create electricity nor do they pollute the air, land, or water, as other powerplants may. Hydroelectric power has played an important part in the development of this Nation's electric power industry. Both small and large hydroelectric power developments were instrumental in the early expansion of the electric power industry.

Hydroelectric power comes from flowing water winter and spring runoff from mountain streams and clear lakes. Water, when it is falling by the force of gravity, can be used to turn turbines and generators that produce electricity.

Hydroelectric power is important to our Nation. Growing populations and modern technologies require vast amounts of electricity for creating, building, and expanding.

Hydropower is an essential contributor in the national power grid because of its ability to respond quickly to rapidly varying loads or system disturbances, which base load plants with steam systems powered by combustion or nuclear processes cannot accommodate.

Hydroelectric plants do not create air pollution, the fuel--falling water--is not consumed, projects have long lives relative to other forms of energy generation, and hydroelectric generators respond quickly to changing system conditions. These favorable characteristics continue to make hydroelectric projects attractive sources of electric power.

Therere a lot of water source of energy that still untapped in our country and havent be developed. Therefore, we make this paper to study more about "Hydroelectric Power."Components of the hydroelectric power1) Dam

The dam is the most important component of hydroelectric power

plant. In fact the name dam is considered to be synonymous to the hydroelectric power plant. The dam is built on a large river that has abundant quantity of water throughout the year. The dam is built at location where the height of the river is sufficiently high so as to get maximum possible potential energy from water.

2) Water reservoir

Water reservoir is the place behind the dam where water is stored. The water in the reservoir is located at the height above the rest of the dam structure. The height of water in the reservoir decides how much potential energy water possesses. Higher the height of water more is its potential energy. The high position of water in the reservoir also enables it to move downwards effortlessly due to gravity.The height of water in the reservoir is higher than the natural height of water flowing in the river, hence water in reservoir is considered to be altered equilibrium. This also helps to increase the overall potential energy of water, which helps ultimately produce more electricity in the power generation unit. 3) Intake or control gates

These are the gates built on the inside of the dam. The water from reservoir is released and controlled through these gates. These are called inlet gates because water enters the power generation unit through these gates. When the control gates are opened the water flows due to gravity through the penstock and towards the turbines. The water flowing through the gates possesses potential as well as kinetic energy.

4) The penstock

The penstock is the long pipe or the shaft that carries the water flowing from the reservoir towards the power generation unit that comprises of the turbines and generator. The water in penstock possesses kinetic energy due to its motion and potential energy due to its height. The total amount of power generated in the hydroelectric power plant depends on the height of the water reservoir and the amount of water flowing through the penstock. The amount of water flowing through the penstock is controlled by the control gates.

5) Water turbines

The water flowing from the penstock is allowed to enter the power generation unit that comprises of the turbines and generator. When water falls on the blades of the turbine the kinetic and potential energy of water is converted into the rotational motion of the blades of the turbine. Due to rotation of blades the shaft of the turbine also rotates. The turbine shaft is enclosed inside the generator. In most of the hydroelectric power plants there are more than one power generation units comprising of the turbine and generator.

There is large difference in height between the level of turbine and level of water in the water reservoir. This difference in height, also called as head of water, decides the total amount of power that can be generated in the hydroelectric power plant.

There are various types of water turbines such as Kaplan turbine, Francis turbine, Pelton wheels etc. The type of turbine used in the hydroelectric power plant depends on the height of the reservoir, quantity of water and the total power generation capacity.

6) Generators

It is in the generator where the electricity is produced. The shaft of the water turbine rotates in the generator, which produces alternating current in the coils of the generator. It is the rotation of the shaft inside the generator that produces magnetic field which is converted into electricity by electromagnetic field induction. Hence the rotation of the shaft of the turbine is crucial for the production of electricity and this is achieved by the kinetic and potential energy of water. Thus in hydroelectricity power plants potential energy of water is converted into electricity. HOW HYDROELECTRIC POWER WORKS ?So just how do we get electricity from water? Actually, hydroelectric and coal-fired power plants produce electricity in a similar way. In both cases a power source is used to turn a propeller-like piece called a turbine, which then turns a metal shaft in an electric generator, which is the motor that produces electricity. A coal-fired power plant uses steam to turn the turbine blades; whereas a hydroelectric plant uses falling water to turn the turbine. The results are the same. The theory is to build a dam on a large river that has a large drop in elevation. The dam stores lots of water behind it in the reservoir. Near the bottom of the dam wall there is the water intake. Gravity causes it to fall through the penstock inside the dam. At the end of the penstock there is a turbine propeller, which is turned by the moving water. The shaft from the turbine goes up into the generator, which produces the power. Power lines are connected to the generator that carry electricity to your home and mine. The water continues past the propeller through the tailrace into the river past the dam.

As to how this generator works, the Corps of Engineers explains it this way:"A hydraulic turbine converts the energy of flowing water into mechanical energy. A hydroelectric generator converts this mechanical energy into electricity. The operation of a generator is based on the principles discovered by Faraday. He found that when a magnet is moved past a conductor, it causes electricity to flow. In a large generator, electromagnets are made by circulating direct current through loops of wire wound around stacks of magnetic steel laminations. These are called field poles, and are mounted on the perimeter of the rotor. The rotor is attached to the turbine shaft, and rotates at a fixed speed. When the rotor turns, it causes the field poles (the electromagnets) to move past the conductors mounted in the stator. This, in turn, causes electricity to flow and a voltage to develop at the generator output terminals."The advantages of hydroelectric power:

1. Using this type of energy to generate electricity is not dependent upon the price of uranium, oil, or other types of fuel. This makes electricity costs lower and more stable, one of its most significant advantages.

2. The pollution created by hydroelectric energy generation is quite minimal. There is some pollution involved in initially constructing the power stations, but this is true of all power plants. It also does not produce radioactive waste or involve the environmental impact of fuel being transported to it.

3. It doesn't require many employees to run a hydroelectric station. According to wikipedia.org, most plants of this type are largely automated. This is another one of the advantages which help keep the cost of hydroelectricity low.

4. Hydroelectric power stations can be set up in almost any size, depending upon the river or stream used to operate them; big enough to power a single home, factory, small town, or large city.

5. Another of its advantages is that hydroelectric is a renewable form of energy, like wind and solar; it does not rely upon finite resources like natural gas or coal to generate power.

6. Hydroelectric stations can operate for many years after they are built. Wikipedia.org states that a number of operational hydro stations were constructed fifty to one-hundred years ago; in contrast to this, IAEA.org indicates that the "design life" of nuclear power plants is generally thirty to forty years.

7. Small hydro electricity generation systems sometimes offer more economic advantages for home owners than solar power, and tend to last longer than solar panels do.

The above-mentioned factors make hydroelectric a form of energy generation which offers advantages with regard to cost, pollution, flexibility of installation, and conservation of resources.

The disadvantages of hydroelectric power:

1. The dams are very expensive to build. However, many dams are also used for flood control or irrigation, so building costs can be shared.

2. Building a large dam will flood a very large area upstream, causing problems for animals that used to live there. 3. Finding a suitable site can be difficult - the impact on residents and the environment may be unacceptable. 4. Water quality and quantity downstream can be affected, which can have an impact on plant life.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 a renewable energy source.

Compared to wind farms, hydroelectricity power plants have a more predictable load factor. If the project has a storage reservoir, it can be dispatched to generate power when needed. Hydroelectric plants can be easily regulated to follow variations in power demand.

Unlike fossil-fuelled combustion turbines, construction of a hydroelectric plant requires a long lead-time for site studies, hydrological studies, and environmental impact assessment. Hydrological data up to 50 years or more is usually required to determine the best sites and operating regimes for a large hydroelectric plant. Unlike plants operated by fuel, such as fossil or nuclear energy, the number of sites that can be economically developed for hydroelectric production is limited; in many areas the most cost effective sites have already been exploited. New hydro sites tend to be far from population centers and require extensive transmission lines. Hydroelectric generation depends on rainfall in the watershed, and may be significantly reduced in years of low rainfall or snowmelt. Long-term energy yield may be affected by climate change. Utilities that primarily use hydroelectric power may spend additional capital to build extra capacity to ensure sufficient power is available in low water years.

CONCLUSIONAs robust global economic expansion continues, the question of where a growing world population will continue to get the electricity to drive the economic engine remains. While most of the new generation supply will come from thermal resources, conventional thinking on the development of new resources and supplies should provide greater emphasis on using sustainable, renewable resources.

Hydroelectric power has an important role to play in the future, and provides considerable benefits to an integrated electric system. This paper has demonstrated an awareness within the industry of the social and environmental impacts of hydropower which need to be addressed for any project; the expertise which exists to avoid or mitigate negative impacts.

The world's remaining hydroelectric potential needs to be considered in the new energy mix, with planned projects taking into consideration social and environmental impacts, so that necessary mitigation and compensation measures can be taken. Clearly, the population affected by a project should enjoy a better quality of life as a result of the project.

Hydro development should go hand in hand with further research and development in the field of other renewable options such as solar and wind power. Energy conservation measures should also be optimized and encouraged. Any development involves change and some degree of compromise, and it is a question of assessing benefits and impacts at an early enough stage, and in adequate detail, with the full involvement of those people affected, so that the right balance can be achieved.

Two billion people in developing countries have no reliable electricity supply, and especially in these countries for the foreseeable future, hydropower offers a renewable energy source on a realistic scale. Impacts of hydro projects are well understood today. Appropriate mitigation and compensation measures must be identified and taken to ensure that any project represents a net gain for affected populations.

Systems exist to provide improved planning processes and better quality decisions, and in turn these ensure that social and environmental concerns are integrated with issues of economic and technical feasibility. The hydropower industry must collaborate with interested stakeholders including regulatory bodies, global financial leaders, and competent interest groups, to develop future standards to ensure balanced and reasonable planning, construction and operation of hydroelectric powerplants.REFERENCEShttp://ga.water.usgs.gov/edu/hyhowworks.htmlhttp://en.wikipedia.org/wiki/HydroelectricityGLOSSARYDam A massive wall or structure built across a valley or river for storing water.Energy The capacity for doing work as measured by the capability of doing work (potential energy) or the conversion of this capability to motion (kinetic energy). Energy has several forms, some of which are easily convertible and can be changed to another form useful for work. Most of the world's convertible energy comes from fossil fuels that are burned to produce heat that is then used as a transfer medium to mechanical or other means in order to accomplish tasks. Electrical energy is usually measured in kilowatt hours and represents power (kilowatts) operating for some time period (hours), while heat energy is usually measured in British thermal units.Generation (Electricity) The process of producing electric energy by transforming other forms of energy; also, the amount of electric energy produced, expressed in watthours (Wh).

Generator A machine that converts mechanical energy into electrical energy.Hydroelectric Power Electric current produced from water power.

Hydroelectric Powerplant A building in which turbines are operated, to drive generators, by the energy of natural or artificial waterfalls.Kinetic Energy Energy which a moving body has because of its motion, dependent on its mass and the rate at which it is moving.

Load (Electric) The amount of electric power delivered or required at any specific point or points on a system. The requirement originates at the energy-consuming equipment of the consumers.Reservoir An artificial lake into which water flows and is stored for future use.

Turbine A machine for generating rotary mechanical power from the energy of a stream of fluid (such as water, steam, or hot gas). Turbines convert the kinetic energy of fluids to mechanical energy through the principles of impulse and reaction, or a mixture of the two.