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The Nuclear Fission Power Plant

The Nuclear Fission Power Plant

Introduction:
Currently, about half of all nuclear power plants are located in the US. There are many different kinds of nuclear power plants, and we will discuss a few important designs in this text. A nuclear power plant harnesses the energy inside atoms themselves and converts this to electricity. This electricity is used by all of us. By now, you should have an idea of the fission process and how it works. A nuclear power plant uses controlled nuclear fission. In this section, we will explore how a nuclear power plant operates and the manner in which nuclear reactions are controlled.

Uranium Preparation:
Earlier we talked about nuclear fission with 235U. In reality, this will not be the only isotope of uranium present in a nuclear reactor. In naturally occurring uranium deposits, less than one percent of the uranium is 235U. The majority of the uranium is 238U. 238U is not a fissile isotope of uranium. When 238U is struck by a loose neutron, it absorbs the neutron into its nucleus and does not fission. Thus, by absorbing loose neutrons, 238U can prevent a nuclear chain reaction from occurring. This would be a bad thing because if a chain reaction doesn't occur, the nuclear reactions can't sustain themselves, the reactor shuts down, and millions of people are without electrical power. In order for a chain reaction to occur, the pure uranium ore must be refined to raise the concentration of 235U. This is called enrichment and is primarily accomplished through a technique called gaseous diffusion. In this process, the uranium ore is combined with fluorine to create a chemical compound called uranium hexafluoride. The uranium hexafluoride is heated and vaporizes. The heated gas is then pushed through a series of filters. Because some of the uranium hexafluoride contains 238U and some contains 235U, there is a slight difference in the weights of the individual molecules. The molecules of uranium hexafluoride containing 235U are slightly lighter and thus pass more easily through the filters. This creates a quantity of uranium hexafluoride with a higher proportion of 235U. This is collected, the uranium is stripped from it, and the result is an enriched supply of fuel. Usually, nuclear power plants use uranium fuel that is about 4% 235U.

Parts of a Nuclear Reactor - Pressurized Water Reactor (PWR):
A typical nuclear reactor has a few main parts. Inside the "core" where the nuclear reactions take place are the fuel rods and assemblies, the control rods, the moderator, and the coolant. Outside the core are the turbines, the heat exchanger, and part of the cooling system.
The fuel assemblies are collections of fuel rods. These rods are each about 3.5 meters (11.48 feet) long. They are each about a centimeter in diameter. These are grouped into large bundles of a couple hundred rods called fuel assemblies, which are then placed in the reactor core. Inside each fuel rod are hundreds of pellets of uranium fuel stacked end to end.
Also in the core are control rods. These rods have pellets inside that are made of very efficient neutron capturers. An example of such a material is cadmium. These control rods are connected to machines that can raise or lower them in the core. When they are fully lowered into the core, fission can not occur because they absorb free neutrons. However, when they are pulled out of the reactor, fission can start again anytime a stray neutron strikes a 235U atom, thus releasing more neutrons, and starting a chain reaction.
Another component of the reactor is the moderator. The moderator serves to slow down the high speed neutrons "flying" all around the reactor core. If a neutron is moving too fast, and thus is at a high-energy state, it passes right through the 235U nucleus. It must be slowed down to be captured by the nucleus and to induce fission. The most common moderator is water, but sometimes it can be another material.
The job of the coolant is to absorb the heat from the reaction. The most common coolant used in nuclear power plants today is water. In actuality, in many reactor designs the coolant and the moderator are one and the same. The coolant water is heated by the nuclear reactions going on inside the core. However, this heated water does not boil because it is kept at an extremely intense pressure, thus raising its boiling point above the normal 100° Celsius.

See More on...http://library.thinkquest.org

History of Batan

Nuclear activities in Indonesia began with the establishment of the State Committee for the Investigation of Radioactivity in 1954, which was assigned to investigate the possibility of radioactive fall-out in Indonesia territory due to nuclea rweapon test in the Pacific Ocean.

Noting that the development and application of atomic energy could enhance the welfare of the people, the Government issued Government Regulation No. 65 on December 5, 1958 establishing the Atomic Energy Council and the Atomic Energy Institute. Thiswaslater followed by the enactment of Act No. 31 year 1964 regarding the Basic Stipulations on Atomic Energy and Government Regulation No. 33 year 1965 which also renamed the Atomic Energy Institute into the National Atomic Energy Agency (Badan Tenaga Atom Nasional or BATAN). However, the 5th of December has been retained as the date of anniversary of BATAN.

In 1965, the operation of the first research reactor (Triga Mark II) was inaugurated in Bandung. In order to improve mastery of nuclear science and technology, several research & development and engineering facilities were built, among others are the Nuclear Technology Research Centre of Pasar Jumat, Jakarta in 1966, and the Nuclear Technology Research Centre of GAMA, Yogyakarta in 1967, where the Kartini research reactor was then built in 1979. To further support the nuclear energy programme, research & development and engineering facilities, the 30 MW Multipurpose Research Reactor was inaugurated in 1987. It's supporting laboratories including facilities for fuel fabrication of research and power reactors, reactor safety testing, production of radioisotope and radiopharmaceutical, management of radioactive wastes and other nuclear facilities have been built in the PUSPIPTEK science and technology research complex in Serpong.

Further development saw the enactment of Act No. 10 in 1997 on Nuclear Energy, which stipulated among others the separation of the executing function on the beneficial applications of nuclear energy (BATAN), from the regulatory function held by the Nuclear Energy Regulatory Agency (BAPETEN).

See more on..http://www.batan.go.id

Hydropower Technologies

The Wind and Hydropower Technologies Program aims to research, test, and develop innovative technologies capable of generating renewable, environmentally responsible, and cost-effective electricity from water. These include marine and hydrokinetic technologies, a new suite of emissions-free renewable technologies that harness the energy from untapped wave, tidal, current and ocean thermal resources. In addition, the program works to develop technologies and processes to improve the efficiency, flexibility, and environmental performance of hydroelectric generation, which currently accounts for approximately 7% of the US electricity supply.

See more on..http://www1.eere.energy.gov

Energy Resource:Wind Power

We've used the wind as an energy source for a long time.

The Babylonians and Chinese were using wind power to pump water for irrigating crops 4,000 years ago, and sailing boats were around long before that.

Wind power was used in the Middle Ages, in Europe, to grind corn, which is where the term "windmill" comes from.

See..more on http://home.clara.net/darvill/altenerg/wind.htm

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