Coal+-+Jee+Won

=**COAL **=


 * 1) How it works
 * 2) A particular example from around the world
 * 3) The energy changes involved
 * 4) Facts and figures about the source
 * 5) The environmental effects

 Coal is a non-renewable energy source because it takes million years to create. It is formed by ancient plants and animals accumulating in swampy forests. For millions of years, a layer of dead plants and animals at the bottom of the swamps was covered by layers of water and dirt, trapping the energy of the dead plants. The heat and pressure from the top layers helped the plant remains turn into coal.  Where coal is from: ** Coal is mined either by surface or underground mining. Before it leaves the mine, it is often cleaned, crushed and sorted.
 * How coal is formed:**
 * 

__**Underground**__: also called deep mining, is used when the coal is buried several hundred feet below the surface.

- Panel mining - Room and pillar - Continuous
 * Types of underground mining:**

__**Surface**__: is used to produce most of the coal in the U.S. because it is less expensive than underground mining. It is also used for coals buried above 200 feet underground.

- Area mining - Contour mining - Pit mining - Auger mining
 * Types of surface mining:**

Power plants burn coal to turn water into steam. Then the steam turns a turbine, a series of wheels with vanes. The turbine then rotates coils on wire in a generator through a magnetic field to produce electricity.
 * How coal works:**

Energy Transfer: Chemical --> Heat --> Kinetic --> Electrical


 * Random facts about coal:**

1. In 1993, the U.S. consumed more than 2 million tons of coal per day and coal production averaged around 30 tons per second, enough to fill a railroad car every 3 seconds.

2. About 2/3 of our coal is transported by rail. One coal train can carry as much as 10 000 tones per trip.

3. 46% of U.S. electrical generators are powered by coal.

4. Electricity is usually not shipped more than 600 miles by wire because of expense and loss of energy. Only 26% of the original energy remains when the electricity is used.

5. A pound of coal supplies enough electricity to power ten 100-watt light bulbs for about an hour.


 * Side effects of using coal:

-** 10 000 tons of sulphur dioxide is the main cause of acid rain, which results in damaging forests, lakes and buildings.

- 10 200 tons of nitrogen oxide is a major cause of smog and acid rain.

- 3.7 million tons of carbon dioxide is the main greenhouse gas, is the leading cause of global warming.

- 720 tons of carbon monoxide is a poisonous gas and contributor to global warming.