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Nuclear Power Plants. Nuclear Power Plants. Nuclear power is generated using Uranium, which is a metal mined in various parts of the world. Some military ships and submarines have nuclear power plants for engines
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Nuclear Power Plants • Nuclear power is generated using Uranium, which is a metal mined in various parts of the world. • Some military ships and submarines have nuclear power plants for engines • Nuclear power produces around 11% of the world's energy needs, and produces huge amounts of energy from small amounts of fuel, without the pollution that you'd get from burning fossil fuels.
How it Works The main bit to remember : Nuclear power stations work in pretty much the same way as fossil fuel-burning stations, except that a "chain reaction" inside a nuclear reactor makes the heat instead.
Nuclear Power Plants • The pursuit of nuclear energy for electricity generation began soon after the discovery in the early 20th century that radioactive elements, such as radium, released immense amounts of energy, according to the principle of mass–energy equivalence. However, means of harnessing such energy was impractical, because intensely radioactive elements were, by their very nature, short-lived (high energy release is correlated with short half-lives). However, the dream of harnessing "atomic energy" was quite strong, even it was dismissed by such fathers of nuclear physics like Ernest Rutherford as "moonshine." This situation, however, changed in the late 1930s, with the discovery of nuclear fission.
Nuclear Fusion When the fusion reaction is a sustained uncontrolled chain, it can result in a thermonuclear explosion, such as that generated by ahydrogen bomb. Non-self sustaining reactions can still release considerable energy, as well as large numbers of neutrons.
Fusion Energy • When deuterium and tritium fuse, the two nuclei come together to form a helium nucleus (an alpha particle) and a high energy neutron.
Nuclear Fuel • In order to give you an idea about the scale of fuel quantities involved in a nuclear power station vis-à-vis traditional power stations, I ask you to imagine that around a pound of nuclear fuel like say Uranium gives the energy equivalent to burning a million gallons of gasoline. This should not come as a surprise since we have already learned that the energy released in a nuclear reaction is the equivalent of the mass change which takes place during the process. It is therefore huge compared to energy which is released as a result of combustion and related chemical reactions during traditional fuel burning.http://www.brighthub.com/engineering/mechanical/articles/2329.aspx#ixzz1156CdRgN
Nuclear Power • Nuclear power is produced by controlled (i.e., non-explosive) nuclear reactions. Commercial and utility plants currently use nuclear fission reactions to heat water to produce steam, which is then used to generate electricity. • In 2009, 13-14% of the world's electricity came from nuclear power.[1] Also, more than 150 naval vessels using nuclear propulsion have been built.
Nuclear Fission Simple diagram of nuclear fission. In the first frame, a neutron is about to be captured by the nucleus of a U-235 atom. In the second frame, the neutron has been absorbed and briefly turned the nucleus into a highly excited U-236 atom. In the third frame, the U-236 atom has fissioned, resulting in two fission fragments (Ba-141 and Kr-92) and three neutrons, all with large amounts of kinetic energy.
Fission • Nuclear fission produces energy for nuclear power and to drive the explosion of nuclear weapons. Both uses are made possible because certain substances called nuclear fuels undergo fission when struck by free neutrons and in turn generate neutrons when they break apart. This makes possible a self-sustaining chain reaction that releases energy at a controlled rate in a nuclear reactor or at a very rapid uncontrolled rate in a nuclear weapon.
Nuclear Power Plant in Pakistan • In Pakistan, nuclear power makes a small contribution to total energy production and requirements, supplying only 2.34% of the country's electricity. Total generating capacity is 20 GWe and in 2006, 98 billion kWh gross was produced, 37% of it from gas, 29% from oil. • The Pakistan Atomic Energy Commission (PAEC) is responsible for all nuclear energy and research applications in the country. • Its first nuclear power reactor is a small (125 MWe) Canadian pressurized heavy water reactor (PHWR) which started up in 1971 and which is under international safeguards - KANUPP near Karachi, which is operated at reduced power.
Nuclear Power Plant in Pakistan • The second unit is Chashma-1 in Punjab, a 325 MWe (300 MWe net) pressurised water reactor (PWR) supplied by China's CNNC under safeguards. The main part of the plant was designed by Shanghai Nuclear Engineering Research and Design Institute (SNERDI), based on Qinshan-1. It started up in May 2000 and is also known as CHASNUPP-1. • Construction of its twin, Chashma-2, started in December 2005. It is reported to cost PKR 51.46 billion (US$ 860 million, with $350 million of this financed by China). A safeguards agreement with IAEA was signed in 2006 and grid connection is expected late in 2010 or in 2011.
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…so cheaper logistics • Produces small amounts of waste. • Nuclear power is reliable.
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.