Nuclear power is generated inside a facility called a nuclear reactor. The plant's source of power is the heat produced by a controlled nuclear fission chain reaction, of either uranium or plutonium. This reaction involves an element such as uranium or plutonium being struck by a neutron and splitting apart. The result of the fission of these large and unstable atoms is the creation of new, smaller atoms, radiation, and more neutrons. Those neutrons then speed out and strike other uranium or plutonium atoms, creating a chain reaction. The chain reaction is controlled by neutron moderators, which vary in type depending on the design of the reactor. These can be anything from graphite rods to simple water.

Once the heat has been released, a nuclear reactor produces electricity in exactly the same manner as any other thermal-based power plant. The heat converts water into steam, and the steam is used to turn the blades of a turbine, which in turn runs the generator. In this way, heat energy is converted to mechanical energy, and then into electricity.

The other major use of nuclear power is for generating electricity. Sixteen percent of the world's electricity is generated by nuclear power, and 19.4 percent of electricity within the United States. According to the IAEA, there were 436 nuclear power plants in operation in 2007. A wide range of reactor designs is used in commercial nuclear power.
Uranium-235 is the form commonly used for energy production because, unlike uranium-238, its nucleus splits easily when bombarded by a neutron. Thorium is much more abundant in nature than uranium.
Thorium can also be used as a nuclear fuel through breeding to uranium-233.

Nuclear power is power (generally electrical) produced from controlled (i.e., non-explosive) nuclear reactions. Commercial plants in use to date use nuclear fission reactions. Electric utility reactors heat water to produce steam, which is then used to generate electricity

Nuclear energy can be used to make electricity. But first the energy must be released. It can be released from atoms in two ways: nuclear fusion and nuclear fission.

In nuclear fission, atoms are split apart to form smaller atoms, releasing energy. Nuclear power plants use this energy to produce electricity.

In nuclear fusion, energy is released when atoms are combined or fused together to form a larger atom. This is how the sun produces energy.

Advantages of Nuclear Energy
The Earth has limited supplies of coal and oil. Nuclear power plants could still produce electricity after coal and oil become scarce.
Nuclear power plants need less fuel than ones which burn fossil fuels. One ton of uranium produces more energy than is produced by several million tons of coal or several million barrels of oil.
Coal and oil burning plants pollute the air. Well-operated nuclear power plants do not release contaminants into the environment. nuclear power plants produce no air pollution or carbon dioxide.
Nuclear energy also offers an alleviation of the global carbon dioxide (CO2) problem that the world can do without.
Disadvantages of Nuclear Energy
The nations of the world now 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 between them. 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 explosions produce radiation. The nuclear radiation harms the cells of the body which can make people sick or even kill them. Illness can strike people years after their exposure to nuclear radiation.
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 1979, the cooling system failed at the Three Mile Island nuclear reactor near Harrisburg, Pennsylvania. Radiation leaked, forcing tens of thousands of people to flee. The problem was solved minutes before a total meltdown would have occurred. Fortunately, there were no deaths.
In 1986, a much worse disaster struck Russia's Chernobyl nuclear power plant. In this incident, a large amount of radiation escaped from the reactor. Hundreds of thousands of people were exposed to the radiation. Several dozen died within a few days. In the years to come, thousands more may die of cancers induced by the radiation.
Nuclear reactors also have waste disposal problems. Reactors produce nuclear waste products which emit dangerous radiation. Because 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 United States plans to move its nuclear waste to a remote underground dump by the year 2010.
In 1957, at a dump site in Russia's Ural Mountains, several hundred miles from Moscow, buried nuclear wastes mysteriously exploded, killing dozens of people.
Nuclear reactors only last for about forty to fifty years.
cost of producing electricity from nuclear energy is somewhat higher than the cost of producing electricity from coal.
nations can create nuclear weapons of mass destruction t is particularly disturbing. Atomic weapons are created through the splitting of the atom and detonated through the process of fission, while hydrogen bombs are detonated through the process of fusion.