Do you mean how much power does it produce? None are working as yet.
Nuclear fission is the working principle under which the nuclear reactors operate.
The stars produce their heat from nuclear fusion reactions. Work on earth to produce controllable nuclear fusion is concentrating on one particular reaction, between deuterium and tritium, because it is the easiest to get going (though hard enough!). Stars operate with other reactions but all of the nuclear fusion type. You can read more in Wikipedia 'Nuclear fusion'
No. Not presently. Existing power plants only use nuclear fission. Nuclear fusion is, due to technological difficulties, the greatest of which is confinement, at least 50 to 100 years away, barring some amazing discovery, of which I cannot presently conceive, given the current state of technology. When the fusion reaction (D + T) occurs energy is released mainly in neutrons. Somehow these neutrons must be absorbed into some material which would then get hot and be able to do work. This engineering aspect has not been solved to my knowledge.
The main disadvantage of fusion is that no scientists have been able to contain a fusion reaction long enough for there to be a net energy gain, but nuclear fission is already producing 11% of the worlds energy needs.The atomic bomb.
It could be if it can be made to work! Two reasons: 1. Fusion does not produce the very active fission products that arise in nuclear fission 2. There are inexhaustible supplies of deuterium in the oceans.
The first work on nuclear fusion was performed in 1933 by Ernest Rutherford. The first nuclear fusion "reactor" was built in 1947 by teams in the UK and USSR. To this day no nuclear fusion "reactor" has been able to produce more energy than had to be put into it to get the reaction started, despite many different experiments on many different designs.
No one work inside a nuclear reactor, it is operated from outside.
Nuclear energy is used to boil water for the purpose of generating energy with the steam. Ice would not work. If you are asking about the water running off of the current reactor issue in Japan, no. This would not work either. The water is being used to cool the rods of the reactor's core. This water becomes very hot and turns to steam. You can not freeze this volume of water fast.
Nuclear fission is the working principle under which the nuclear reactors operate.
The stars produce their heat from nuclear fusion reactions. Work on earth to produce controllable nuclear fusion is concentrating on one particular reaction, between deuterium and tritium, because it is the easiest to get going (though hard enough!). Stars operate with other reactions but all of the nuclear fusion type. You can read more in Wikipedia 'Nuclear fusion'
nuclear fusion reaction
The absorption of a free moving neutron by the atom's nucleus
It really depends on the nuclear reactor, but many are built to work specifically with that isotope.
The first demonstration nuclear reactor was built in USA by Enrico Fermi in Chicago Stadium. Fermi was an Italian Physicist, best known for his work on Chicago Pile-1 (the first nuclear reactor). on 26 June 1954, in the town of Obninsk, near Moscow in the former USSR, the first nuclear power plant was connected to an electricity grid to provide power to residences and businesses. Nuclear energy had crossed the divide from military uses to civilian applications.
In a nuclear power plant (nuclear reactor) the radioactivity of uranium is not a problem in normal work conditions.
The fusion of Hydrogen into Helium causes heat and radiation to occur.
Some nuclear power reactors work with low enriched uranium; CANDU reactors work with natural uranium.