COAL+-+Kangan

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= __COAL __ = Coal is a non-renewable energy resource because it takes million of years to form.


 * __Formation of Coal:__**
 * [[image:Picture_20.png height="190" align="right"]]It occurred hundreds of millions of years ago when there was extensive plant growth in places like flooded forests and swamps.
 * When the plants died, they fell into the water or swamps.
 * Due to lack of oxygen in the water, the dead plants did not decay completely and instead turned into a layer of peat.
 * Gradually, sediment brought in by the water, covered the peat, burying it deeper and compressing it, forcing the moisture out and reducing the volume of the peat.
 * As the peat was buried deeper, the high temperature and pressure, gradually turned it into lignite, a soft brown coal.
 * The lignite was buried deeper and after a long time, the increased pressure and temperature converted it into harder, more superior coal with a higher % of carbon.
 * As the temperature and the amount of time the coal was buried increased, soft black bituminous coal and then hard, black anthracite coal were formed.




 * __How it works?__**


 * Coal is burned in a boiler.
 * Water in the boiler pipes turns into steam.
 * The steam travels through the pipes to the turbine.
 * The steam causes the turbine blades to spin.
 * The spinning blades turn a shaft connected to the generator.
 * In the generator, big magnets spin close to coils of wire.
 * This produces electric current in the wires.
 * Electricity is therefore produced and is delivered to homes, schools and businesses through wires.

(Source: http://library.thinkquest.org/6075/coal.html)

__**An example: **__

Big Stone Power Plant is a coal fired power station near Big Stone, in South Dakota.


 * Info:**
 * Fuel source: sub-bituminous coal
 * Opened: 1975
 * Where: generates electricity for parts of South Dakota, North Dakota and Minnesota.
 * Plant nameplate capacity: 456 MW (megawatts)
 * Area: 2,200 acre plot
 * No. of employees: about 75


 * Emissions data:**
 * 2006 CO 2 Emissions: 3,784,492 tons
 * 2006 SO 2 Emissions: 11,986 tons
 * 2006 SO 2 Emissions per MWh:
 * 2006 NO x Emissions: 14,681 tons
 * 2005 Mercury Emissions: 150 lb.

__**Energy Transfers Involved: **__

To convert coal into electricity, the following energy transfers take place: (Source: http://www.bbc.co.uk/schools/gcsebitesize/science/aqa/energy/mainselectricityrev1.shtml)
 * Coal is burnt to heat water in a boiler and convert it to steam - **chemical energy to heat energy**
 * This inturn rotates a turbine like in windmills - **heat energy to kinetic energy**
 * This turbine is attached to a generator which is used togenerate electricity - **kinetic energy to electrical energy**


 * __Fast Facts and Figures:__**
 * Coal ash, a byproduct of coal combustion, is used as filler for tennis rackets, golf balls, and linoleum.
 * Texas is the top coal-consuming state. It uses about 100 million tons each year.
 * The average coal miner is 50 years old and has 20 years of experience.
 * Coal provides over 23% of the world’s energy needs and it generates approximately 39% of the world’s electricity. Almost 70% of total global steel production is also dependent on burning coal.
 * Coal emits 29% more carbon per unit of energy than oil, and 80% more carbon than natural gas.
 * Coal generates approximately half of all the electricity used in the United States.

(Source: http://www.teachcoal.org/aboutcoal/articles/fastfacts.html)


 * __Environmental Effects of Coal:__**

There are a number of environmental effects of coal mining and burning, such as:
 * Release of nitrogen oxide and sulphur dioxide - leading to acid rain
 * Interference with groundwater and water table levels
 * Contamination of land and waterways and destruction of homes from fly ash spills
 * Coal-fired power plants without effective fly ash capture are one of the largest sources of human-caused background radiation exposure
 * Coal-fired power plants shorten nearly 24,000 lives a year in the United States, including 2,800 from lung cancer.
 * <span style="font-family: Arial,Helvetica,sans-serif;">Release of carbon monoxide - a poisonous gas and a contributor to global warming
 * <span style="font-family: Arial,Helvetica,sans-serif;">Release of carbon dioxide - main greenhouse gas, enhancing the greenhouse effect and leading to global warming

(Source: http://en.wikipedia.org/wiki/Coal#Environmental_effects)