Nuclear Power Station :
Nuclear energy is available as a result of fission reaction. In a typical system, Uranium 235 is
bombarded with neutrons and Heat energy is released. In chain-reaction, these release more neutrons,
since more Uranium 235 atoms are fissioned. Speeds of Neutrons must be reduced to critical speeds
for the chain reaction to take place. Moderators (= speed-reducing agents like graphite, heavy water,
etc). are used for this purpose. Nuclear fuel rods (of Uranium 235) must be embedded in speedreducing agents. Further, control rods (made of cadmium) are required since they are strong neutronabsorbers and help in finely regulating this reaction so that power control of the generator is precisely
obtainable. When control rods are pulled out and are away from fuel rods, intensity of chain reaction
increases, which increases the power output of the system. While if they are pushed in and closer to
the fuel rods, the power-output decreases. Thus, the electrical load demand on the generator decides
(automatically) the control-rod positions through a very sophisticated control system.
Advantages :-
1. Quantity of fuel required is small for generating a given amount of electrical energy, compared
to that with other fuels.
2. It is more reliable, cheaper for running cost, and is efficient when operated at rated capacity.
Disadvantages :-
1. Fuel is expensive and not abundantly available everywhere. 2. It has high capital cost.
3. Maintenance charges are high. 4. Nuclear waste disposal is a problem.
Nuclear energy is available as a result of fission reaction. In a typical system, Uranium 235 is
bombarded with neutrons and Heat energy is released. In chain-reaction, these release more neutrons,
since more Uranium 235 atoms are fissioned. Speeds of Neutrons must be reduced to critical speeds
for the chain reaction to take place. Moderators (= speed-reducing agents like graphite, heavy water,
etc). are used for this purpose. Nuclear fuel rods (of Uranium 235) must be embedded in speedreducing agents. Further, control rods (made of cadmium) are required since they are strong neutronabsorbers and help in finely regulating this reaction so that power control of the generator is precisely
obtainable. When control rods are pulled out and are away from fuel rods, intensity of chain reaction
increases, which increases the power output of the system. While if they are pushed in and closer to
the fuel rods, the power-output decreases. Thus, the electrical load demand on the generator decides
(automatically) the control-rod positions through a very sophisticated control system.
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| block diagram of nuclear power station |
1. Quantity of fuel required is small for generating a given amount of electrical energy, compared
to that with other fuels.
2. It is more reliable, cheaper for running cost, and is efficient when operated at rated capacity.
Disadvantages :-
1. Fuel is expensive and not abundantly available everywhere. 2. It has high capital cost.
3. Maintenance charges are high. 4. Nuclear waste disposal is a problem.
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