07-03-2011, 03:58 PM
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NUCLEAR POWER PLANT
1. INTRODUCTION: - A nuclear power plant is a place where people make electricity using heat from nuclear reactions. A nuclear power plant has a place where the nuclear reaction happens called a reactor. The plant also has machines which remove heat from the reactor and make electricity. Electricity made by nuclear power plants is called nuclear power. Nuclear power plants are usually located near water to remove the heat the reactor makes. Some nuclear power plants use cooling towers to do this.
Nuclear power plants use uranium as fuel. When the reactor is on, uranium atoms inside the reactor split into two smaller atoms. When uranium atoms split, they give off a large amount of heat. This splitting of atoms is called fission. The most popular atoms to fission are uranium and plutonium. Today, fission only happens in nuclear reactors. In nuclear reactors, fission only happens when the reactors parts are arranged properly. Nuclear power plants turn their reactors off to replace old fuel with new fuel. There are about five hundred nuclear power plants in the world, with many in the United States, France, and Japan.
Uranium atoms are slightly radioactive. The atoms produced when uranium breaks apart are strongly radioactive. Some famous accidents at nuclear power plants were the Chernobyl accident at Chernobyl in Ukraine and the Three Mile Island accident at Three Mile Island in the United States.
Nuclear power is the fourth largest of electricity in India after thermal, hydro and renewable sources of electricity. As of 2010, India has 20 nuclear power plants in operation generating 4,560 MW while 4 other are under construction and are expected to generate an additional 2,720 MW. India's nuclear power
Industry is undergoing rapid expansion with plans to increase nuclear power output to 64,000 MW by 2032. The country is involved in the development of nuclear fusion reactors through its participation in the ITER project and is a global leader in the development of thorium-based fast breeder reactors.
2. NUCLEAR POWER PLANT:-
Nuclear power plants are powered by Uranium. In a process known as nuclear fission, uranium atoms are split to produce large amount of energy which is eventually converted to heat. The enormous amount of heat created, boils the water to produce steam, which is used to rotate turbines. These turbines in-turn spin the shaft of the generator. As the generator gets into action, the coils of wire within the generator are spun in a magnetic field to produce electricity. A nuclear reactor maintains and controls the nuclear reaction within the plant to produce energy. In the United States, pressurized water reactors and boiling water reactors are used in nuclear power plants. Though there are a few security concerns about operations of a nuclear power plants, they are necessary as an alternative energy source, to cope up with the ever increasing energy requirements. Owing to low levels of emission, this cost-effective source of power is steadily becoming a popular source. It is estimated that the demand for nuclear energy for production of electricity will increase by 20%, by 2030. Knowing how does a nuclear power plant work, and the safety measures ensured in the process, will perhaps make many people change their critical stance on nuclear plants.
The following table shows the places where nuclear plant available in India:
Nuclear Power Plants In India
NAME OF THE PLANT/DETAILS TARAPUR(MAHARASTRA) RANA-PRATAP SAGAR(KOTA,RAJASTHAN) KALPAKKAM CHENNAI(TAMIL NADU) NARORA(UP) KAKRAPAR(GUJARAT)
3. SELECTION OF SITE FOR NUCLEAR POWER PLT:
The following points should be kept in view while selecting the site for a nuclear power station
(i) Availability of Water
As sufficient of water is required for the cooling purposes, therefore the plant site should be located where ample quantity of water is available.
(ii) Disposal of Waste
The waste produced by fission in nuclear power station is generally radio active which must be disposed off properly to avoid health hazards. The waste should either be buried in a deep trench or disposed off in a sea quite away from the sea shore. Therefore the site selected for such a plant should have adequate arrangement for the disposal of radio active waste.
(iii)Distance from populated areas
The site selected for a nuclear power station should be quite away from the populated areas as there is a danger of presence of radio activity in the atmosphere near the plant. However, as a precautionary measure, a dome is used in the plant which does not allow the radioactivity to spread by wind or underground waterways.
(iv)Transportation Facilities
The site selected for a nuclear power station should have adequate facilities in order to transport the heavy equipments during erection and to facilitate the movement of workers in the plant.
From the above mentioned factors it become apparent that ideal choice for a nuclear power station would be near sea or river and away from thickly populated areas.
4. INSIDE A NUCLEAR POWER PLANT:-
An assembly giving large amount of nuclear energy through fission reaction in a controlled rate is called a nuclear reactor. It is a system that contains and controls sustained nuclear chain reactions. The controlled chain reaction and liberation of large amount of energy is the basis of nuclear reactor. The first fission reaction results in the production of fast moving neutrons. These neutrons when passed through moderators become thermal neutrons. Controlled fission reaction can be done by controlling the thermal neutrons used in reaction. Sustained chain reaction with steady liberation of energy is maintained in a nuclear reactor. Reactors are classified into different categories based on the fuel used.
