Nuclear power is the power nurtured from the smallest element of matter and that is atom. Nuclear power can be man made or natural, natural as in case of nuclear reaction in case of stars in our universe providing heat and light and could be man made like the power harnessed in nuclear power plants. The energy in nuclear plants is result of controlled nuclear reaction in nuclear reactors. Nuclear energy provides for approximately 16% of the world's total electricity supply. There are two types of nuclear reactions:
• Nuclear fission reaction
• Nuclear fusion reaction
In nuclear fission reaction a heavy nucleus splits up into two main fragments of lighter nuclei and several neutrons when bombarded by a projectile on slow thermal neutrons.
Where as in nuclear fusion reaction two nuclei are joined together or fused producing excessive burst of energy only under high temperature conditions.
Nuclear Power Plant Block Diagram
Well when ever we hear the words "Nuclear Power," different pictures pops up in our mind: concrete coolant towers emitting torrents of steam or a mushroom cloud rising high into the sky but in reality nuclear power plants work on very simple sequence that is heat produced during a nuclear reaction typically via nuclear fission reaction in nuclear reactor is utilized to heat up water which produces steam. This steam is pressurized and is used to rotate turbines which generates electricity. The image here depicts the sequence of chain reactions which take place in a nuclear reactor.
The nuclear power also called atomic power is the power of future should be prevailed precisely because it is an important carbon-free source of power. Nuclear power can come from the fission of uranium, plutonium or thorium or the fusion of hydrogen into helium these minerals are mined from the earth crust. Most nuclear power plants today use enriched uranium in which the concentration of uranium isotope U-235 is increased from 0.7 percent U-235 to about 4 to 5 percent U-235.
Uranium Fuel Bundle
Uranium dioxide (UO2) powder is compacted to cylindrical pellets and sintered at high temperatures to produce ceramic nuclear fuel pellets with a high density and well defined physical properties and chemical composition. A grinding process is used to achieve a uniform cylindrical geometry. Such fuel pellets are then stacked and filled into the metallic tubes. The metal used for the tubes depends on the design of the reactor. Stainless steel was used in the past, but most reactors now use a zirconium alloy which, in addition to being highly corrosion-resistant, has low neutron absorption. The tubes containing the fuel pellets are sealed: these tubes are called fuel rods. The finished fuel rods are grouped into fuel assemblies that are used to build up the core of a power reactor.
Nuclear power is very efficient source as compared to power generated from burning of fossil fuels for example one ton of uranium produces more energy than is produced by several million tons of coal or several million barrels of oil also Coal and oil burning plants pollute the air while well-operated nuclear power plants do not release contaminants into the environment.
Advantages of nuclear power
• Efficient: Nuclear plants can produce significant quantities of electricity, to about 2GW (at the large end of the range).
• Reliable: As long as there is supply of fuel to the reactor there will be continuous power supply. A nuclear can produce electricity uninterrupted for years together after reaching its criticality.
• Clean: Nuclear power is "zero-carbon" power. Nuclear power is considered to be green source of power it do not pollute environment by releasing green house gasses.
Disadvantages of nuclear power
• Radiation: Nuclear power plants produce radiation which harms the cells of the body which can make people sick or even kill them.
• Meltdown: One possible type of reactor disaster is known as a meltdown. In such an accident, the fission reaction goes out of control, leading to a nuclear explosion and the emission of great amounts of radiation. In 1986, a disaster struck Russia's Chernobyl nuclear power plant. In this incident, a large amount of radiation escaped from the nuclear reactor. Hundreds of thousands of people were exposed to the intense radiation. Several died within a few days. In the years to come, thousands more may die of cancers induced by the radiation.
• Waste disposal: Nuclear reactors also have waste disposal problems. Nuclear Reactors produce nuclear waste products which emit dangerous radiation. As they could kill people who touch them, they cannot be thrown away like ordinary garbage. Currently, many nuclear wastes are stored in special cooling pools at the nuclear reactors. The nuclear waste is sealed and kept in pools to cool these waste to allow the radioactivity to die away and is not allowed to get exposed to environment.
Some people think that nuclear energy is here to stay and all must learn to live with it utilize green source of power. Others say that we should get rid of all nuclear weapons and power plants. Both sides have their say as there are advantages and disadvantages to nuclear energy. Still others have opinions that fall somewhere in between.
In present scenario the nations of the world have more than enough nuclear bombs to kill every person on Earth. The two most powerful nations -- Russia and the United States -- have about 50,000 nuclear weapons. What if there were to be a nuclear war? What if terrorists got their hands on nuclear weapons?? Or what if nuclear weapons were launched by accident??
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.
