Nuclear Energy

Nuclear energy produces electricity through a process called fission. In 1956, the first commercial nuclear power plant opened in England. In the United States, as of 2008, there were 104nuclear reactors producing about 20 percent of the country's electricity needs.Nuclear energy doesn't produce greenhouse gases , and no pollution is released into the air. Compared to coal or other fossil fuels, the emissions from nuclear power plants are very clean. Some people say we should build more power plants to reduce greenhouse gases pollution. However, the waste from nuclear energy stays dangerously radioactive for thousands of years.
Other than fission, there is another kind of nuclear energy is fusion. This is the energy that powers the sun and stars. However, scientists cannot yet control the process on earth. If scientists could learn how to create and control fusion, it could become an energy source that is clean and would never run out.

bibliography:nuclear energy by Jim Ollhoff

How does fission work?

Everything is made up of tiny atoms. Atoms are made up of protons, neutrons and electrons. Some elements, like helium are small, composed of only one proton. Some are large. Uranium, the heaviest element in nature, has 92 protons.
Because uranium is so heavy, the atoms break apart easily. This is why uranium is used as a fuel in nuclear reactors. Fisson happens when a neutron crashes into a uranium atoms and spilt it. The neutrons from that atoms then crash into other atoms, and so on. When huge numbers of neutrons are crashing into atoms, it is called a chain reaction. A chain reaction produces heat.
At the centre of the nuclear power plant is reactor, where fission takes place. Inside the reactor is a supply of uranium, called the core. If the uranium reactor were left on its own, the chain reaction would get out of control. It would became so hot that that the reactor would melt, and then it would pass through the floor. Dangerous radiation would escape in the air. This would be a terrible disaster called the meltdown. To prevent this, scientist have used cooling rods or control rod, that are lowered into the nuclear reactor. This keep the reactor from getting too hot,and control the change reactions.

How does nuclear power plant produce eletricity

A nuclear power plant controls the chain reaction of the uranium to produce heat in the reactor. Water is pumped through the hot reactor. Water is pumped through the hot reactor. Water heats up and turns into steam turns turbines. Then, a generator converts the motion of the turbines into electricity.
Uranium is used for fuel in power plants. It is a non-renewable energy source, but it is fairly common. Much of te uranium used in North America is mined in the western states.
Uranium itself is radioactive. Radioactivity is a stream of particles or rays given off by certain kinds of matter. Radiation can cause serious illnesses or death. The uranium is kept in a sealed building called a containment building. Radiation does not get into the water or air unless there is an acident or disaster.

Advantages and Disadvantages of nuclear energy

Advantages:
1. produces no greenhouse gases
2. steam is released into the atmosphere by nuclear plants
3. such a powerful source of energy, more than fossil fuels.
4. from a relatively small amount of nuclear fuel, a very large amount of energy is produced

Disadvantages:
1. the biggest problem with the nuclear energy is the waste it produces is highly radioactive
2. the waste is made by using up all the fuel in nuclear reactors
3. the waste remains radioactive for 10 000 years or more
4. very little place to store the waste




The story of Three Mile Island:

On March 28, 1979, a technical problem occurred in a water pump at Three Mile Island. The water was cooling the reactor. When the pump failed, the reactor began to overheat. Another technical failure occurred in a halve that was releasing excess steam. The operators of the plant didn't have enough information to figure out what the problem was, and they made a number of errors that made the problem worse.
During the tense next few days, engineers tried to cool the reactor and solve the other problems that were happening inside the plant. The government of Pennsylvania advised children and pregnant women, the most vulnerable to radioactivity , to leave the area. Radioactivity was released into the air, and almost half the reactor melted down. However, the reactor meltdown was contained and eventually cooled. Although no one died in the accident, it made people fearful of the nuclear industry.

Bibliography:nuclear energy by Jim Ollhoff

Fusion energy: The Hope and the Reality

Scientists have been trying to make fusion power for 50 years. While knowledge has constantly advanced, it's unclear if the technological hurdles will be overcome anytime soon. It takes a lot of energy to make a process hot enough for fusion. However, if it works, fusion will produce more energy than is required to make it. Scientist believed that fusion will have no waste products-no greenhouse gases or long-term radioactive waste.
They also believed that fusion power plants will be safer than fission power plants. With fusion, there is little chance of melting down or releasing radiation. while fusion reactors would still be radioactive , most scientist believed that the reactor elements would only be radioactive for 50 to 100 years. The radioactive elements from fission reactors, on the other hand, will stay radioactive for thousands of years.

Bibliography:nuclear energy by Jim Ollhoff