Why do we need nuclear energy?

Answer 1

Generation of electricity in a nuclear station is similar to a coal-fired steam station. The difference is the source of heat. Fission, or splitting, of uranium atoms replaces the burning of coal as the source of heat.

When you take a loose neutron and you get it to collide into a uranium-235 atom, the atom will split and release energy and 3 more neutrons, causing a chain reaction. This chain reaction causes other uranium-235 atoms to split as well. This would get out of hand very quickly so metal rods are installed into the reactor's core that absorb 2/3 of the neutrons that are released from the reactions that have occurred. So the reaction is controlled, and it produces a great deal of heat. The heat is used to boil water, and the steam is then used to produce electricity in turbines.

1. The Fuel

The fuel used in nuclear generation is uranium 235. It is manufactured as small round pellets. A single pellet is less than an inch long, but produces the energy equivalent to a ton of coal. The pellets are placed end to end into fuel rods 12 feet long. Over 200 of these rods are grouped into what is known as a fuel assembly.

2. Reactor

The process of producing electricity begins when uranium atoms are split (i.e. fission) by particles known as neutrons. Uranium 235 has a unique quality that causes it to break apart when it collides with a neutron. Once an atom of uranium 235 is split, neutrons from the uranium atom are free to collide with other atoms of the uranium 235. A chain reaction begins and the chain reaction produces heat. This reaction is controlled by rods which absorb neutrons.

Control rods are inserted among the fuel assembly rods that hold the uranium pellets. When they are in place, they absorb the atomic particles that would normally initiate the chain reaction. When they are withdrawn from the fuel assembly, fission is allowed to occur.

3. Pressurizer

The heat produced in the reactor is transferred to the first of three water systems: the primary coolant. The primary coolant is heated to over 600 degrees Fahrenheit. In a pressurized water reactor, a pressurizer keeps the water under pressure to prevent it from boiling.

4. Steam Generator

The hot, pressurized water passes through thousands of tubes in nearby steam generators. These tubes are surrounded by another water system called the secondary coolant. The heat from the primary coolant is transferred to the secondary coolant, which then turns into steam.

The primary and secondary systems are closed systems. This means that the water flowing through the reactor remains separate and does not mix with the water from the other system or the lake.

5. Turbine

The steam is piped from the containment building into the turbine building to push the giant blades of a turbine. The turbine is connected to an electric generator by a rotating shaft. As the turbine blades begin to spin, a magnet inside the generator also turns to produce electricity.

6. Condenser Coolant

After turning the turbines, the steam is cooled by passing it over tubes carrying a third water system, called the condenser coolant or lake water. The steam is cooled so it condenses back into water and is returned to the steam generator to be used again and again.

7. Lake or Cooling Towers

At some nuclear stations, such as Oconee and McGuire, lake water flows through thousands of condenser tubes to condense steam back to water. It is then discharged down a long canal (for cooling) and eventually enters the main part of the lake.

At other plants such as Catawba Nuclear Station, the condenser cooling water is circulated through cooling towers to remove the extra heat it has gained. The water is pumped to the top of the cooling towers and is allowed to pour down through the structure. At the same time, a set of fans at the top of each tower pulls air up through the condenser water. This lowers the temperature of the water by about 24 degrees. After it is cooled, the condenser water flows back into the turbine building to begin its work of condensing steam again.

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Answer 2

It requires Fuel rods which are usually 3% Uranium-235 (97% Uranium-238). Although Uranium-233 or Plutonium-239 based fuels have also been used. Special reactor designs have been developed (but not placed in service) that can burn fuels that contain all transuranic elements (not just Plutonium), these reactors are actually able to burn nuclear waste from "ordinary" reactors leaving only short halflife fission products that would not require storage for more than a couple hundred years before they would be safe.

Answer 3

No a simple Wind Turbine can provide the same kind of heat that can provide enough energy to be classified as "nuclear energy". This can be presumed under the classification of Newtons 5th general law of Practise but must be considered within the laws of Shipmass. (See Shipmass pre-enstasia) It's basic fisics.

Answer 4

It's not essential, but it makes a useful contribution to energy demand, and for countries like France which have little fossil fuels on their own territory, it is more desirable than for countries such as the US which had plenty of coal, oil, and gas. More recently with emphasis on limiting emissions from burning fossil fuels it has an added attraction in that respect.

Another Answer:

It is essential, as the proliferation of fossil fuel power plants is contributing to the greenhouse effect that is compromising the future of the Earth. Also, fossil fuels are limited and we will run out in the not too distant future. Look at the price of oil (and gas) and you will see that dependency on oil is a problem.

Answer 5

As much as one can comfortably learn. It is a vital subject to know about these days regardless of one's opinions on it.