Different sources of generation , transform various forms of energy into electricity. Thus , dams make use of the strength of rivers , wind farms use wind power , geothermal plants use the heat of volcanoes and thermal plants use the heat generated by combustion to convert it into energy.

Well, today we will focus on the following routes of obtaining electric power. The methods will have to analyze , obtaining electric power by coal , natural gas and nuclear energy.

COAL

In order to use coal , sedimentary rock is often burned to generate electricity, but must first be extracted from the earth . This is achieved through two methods: surface mining and underground . Surface mining is used to extract coal within 200 feet of the surface of the Earth. Underground mining is done by drilling the earth , creating deep holes. Miners take elevators to hundreds of meters below the surface of the earth , dig coal using special machines and conveyor belts loaded into returning to the surface.
After the coal has been extracted from the earth, is rarely pure as it is mixed with other elements , such as dirt, ash and sulfur , so, preparation plant cleans to remove these impurities. After it is cleaned , it is sprayed on a machine up to 50 mm in size.
Finally, the coal must be burned to generate electricity. After the coal has been delivered to the power plant , pulverized and burned in a boiler. This boiler is connected to a pipe with water, thermal energy here plays its part , the water boils, producing steam . This steam is piped to the turbines . The steam turns turbines , mechanical energy , which ultimately generate electrical energy.

 

 

Compared to other energy sources such as oil and natural gas, coal is cheap, which, according to analysts at free market policies, will decrease electricity bills for consumers and businesses.
But coal-fired plants are a major source of air pollution, according to the Fund for Environmental Defense. Burning coal contributes to acid rain and releases large amounts of carbon dioxide, to be exact, double carbon dioxide per unit of energy generated than any other fuel, which worsens global warming.

http://www.cechsa.com/node/13

http://www.tenaris.com/es-ES/Products/PowerGeneration/CoalFiredPowerPlants.aspx

http://europa.eu/legislation_summaries/energy/european_energy_policy/l27068_es.htm

 

NATURAL GAS

Obtaining energy from natural gas is similar to that of carbon, the main change, apart from other technical details of the various thermal plants is the fuel.

When you think of gas, you could think of combustion or ignition. Convert natural gas into electricity starts just that way. To produce electricity, natural gas is burned to produce gases of high temperature combustion passing through a turbine (a type of engine that converts chemical energy into mechanical energy). When the gas passes through this process, made ​​to rotate the turbine blades, which rotates large magnets that are embedded into metal coils, which causes the movement of electrons. The latter is what generates electricity.

A great advantage of the natural gas with coal is much less pollution emitted, for example, the amount of carbon dioxide released into the atmosphere, it is much smaller. On the other hand, is much more affordable than the oil, which due to its very extensive use, has an exorbitant price.

 

http://www.firstchoicepower.com/centro-de-aprendizaje/noticias-energeticas/relacion-entre-el-gas-natural-y-la-electricidad

http://www.solociencia.com/ingenieria/10012204.htm

 

NUCLEAR POWER PLANTS

A central or nuclear plant is an industrial facility used for the generation of electricity from nuclear energy. Characterized by the use of fissile nuclear fuel which provides heat by nuclear reactions, which in turn is employed, through a conventional thermodynamic cycle, to cause movement of generators that convert electrical energy into mechanical work. These plants consist of one or more reactors.
The core of a nuclear reactor consisting of a container or vessel, inside which blocks of an insulating material are housed radioactivity, commonly treated graphite filler or concrete comprising nuclear fuel fissile material (uranium-235 or plutonium-239).

Nuclear power plants consist mainly of four (or five) parts:

-The nuclear reactor, where the nuclear reaction.

-The steam generator ( not in all nuclear power plants)

-The turbine, which drives an electric generator to produce electricity from steam expansion.

-The condenser, a heat exchanger that cools the steam transforming back into liquid.

The nuclear reactor is in charge of making the fission or fusion of nuclear fuel atoms, such as uranium, plutonium generated as waste, releasing a large amount of heat energy per unit mass of fuel.

The steam generator is a heat exchanger that transfers heat from the primary circuit, through which water is heated in the reactor circulates, the secondary circuit, changing the water into steam which is subsequently expanded in the turbine, producing movement of the fabric, which in turn rotate the generator, producing electricity. Through a transformer to the electrical network, voltage electricity transmission is increased.

After expansion in the turbine, the steam is condensed in the condenser. A condensed time, returns to the nuclear reactor to begin the process again.

Nuclear plants are always close to a cold water supply such as a river, lake or sea, to the cooling circuit using either cooling towers or not.

But nuclear fission industry presents various dangers , that now have not a quick fix. These dangers could end up having a major impact on the environment and in living organisms if released into the atmosphere , or discharges on the environment , even to cause death , and condemn future generations with mutations .. . Therefore, nuclear power plants are required a heavy security , they can avoid these incidents , but sometimes may become insufficient ( Chernobyl ) , because they are trying to save money in building and only gets minimal security.

In addition to radiation , another factor to consider is the constant risk of a possible nuclear explosion, although the latter is very unlikely with current safety systems of nuclear power plants , have recently had a couple of cases , especially the one that occurred in Japan , which to this day continues to have a devastating rates of radioactivity.

 

 

 

http://www.angelfire.com/sc/energianuclear/peligros.html

http://www.unesa.net/unesa/html/sabereinvestigar/largoviaje/nucleares.htm

http://www.tecnun.es/asignaturas/Ecologia/Hipertexto/07Energ/130EnNuclear.htm