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Maily Tran

on 9 January 2014

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Transcript of COAL

What is coal?

a nonrenewable energy source that comes from the decomposing remains of ancient plants underground.
Why is it nonrenewable?
Although coal can be replenished, its supplies are limited due to the millions of years it takes to reform.
How Do We Use Coal?
We... burn it!
generate electricity
iron and steelmaking
multiple industries (such as cement, brick, paper, and limestone)
heating homes & businesses
-decreases the United States' dependence on foreign fuels
-cheaper compared to other energy sources
-by-products from burning coal could be recycled for other uses (i.e. creating ocean reefs for animal habitats, building roads)
-weather doesn't greatly impact power production
-a reliable source of electricity
-mining is dangerous and can result in health issues
-nonrenewable...only about
112 years
left of usage worldwide
-burning coal releases harmful emissions (such as carbon dioxide) that pollutes the air and contributes to the greenhouse effect
-transporting coal can be expensive
-natural habitats nearby coal mines can be damaged
Coal Mining
surface Mining
-coal is close to the surface (within 200 ft)
-less expensive, more commonly used method
1. The soil & rock covering coal, called "overburden," is removed and stored
use machines such as bulldozers, power shovels, and drag lines.
3. The overburden is replaced, covered with topsoil, and the area is seeded & fertilized process known as "reclamation"
2. The coal is drilled, broken up, and mined.
Underground Mining
-coal seam is several hundred feet below the surface
Converting Coal into Electricity
Effects of Harvesting Coal
How Efficient is Coal at Making Electricity?
My Opinion
Two methods:
1. room-and-pillar mining:
rooms are cut into the coal bed using
a machine called the continuous miner...leaves behind pillars to support mines roofs and walls for further mining until mine collapses
2. longwall mining:
specially shielded machines cut out coal
and allow mined area to collapse in a controlled manner--> coal falls into conveyor for removal
plant fertilizer
1. The coal is mined and transported to a power plant.
2. Coal is pulverized into a fine powder and blown into the boiler where it is burned at high temperatures.
Social Interest
3. The water in the pipes around the boiler is heated by the burning coal to create steam.
4. The steam travels through the turbine and causes its blades to spin
5. The turbine spins the electromagnet inside copper coils in a generator.
6. The spinning electromagnet produces electricity that is transferred
7. The steam is turned back into water by the condenser and is sent to the boiler through pipes.

Although coal is a valuable resource, I am against using it because:
It negatively affects the environment with pollution and is a major contributor to global warming
Coal mining can be hazardous to miners and the areas surrounding mines.
It will eventually run out... the supply of coal isn't limitless.
-Before the first settlers came to the New World, North American Indians had already been using coal... Hopi Indians baked clay pottery with coal
Energy Transformations
-mining and transporting coal:
motion energy
from the generator to the transformer.
-crushing coal into powder and blowing it into boiler: motion energy
-burning the coal in boiler that creates steam: chemical energy to thermal energy
-steam spinning turbine's blades: thermal energy to mechanical energy
-generator producing electricity: mechanical energy to electrical energy
-There is debate over a new Environmental Protection Agency (EPA) regulation released in September 2013 which said... It is mandatory for new coal-fired power plants to utilize costly technology that would capture at least 40% of carbon dioxide emissions.
scientists and environmentalists: for it
House of Representatives Republicans, and
coal & utility companies: against it
-Keith Urban and Nicole Kidman are part of the anti-coal movement in Australia.
-Coal is a major source of income for many areas worldwide.
-When coal is mined, toxic waste and rubble is sometimes dumped at surrounding areas, damaging the ecosystems.
-Approximately 1 pound of coal is needed to
produce one kilowatt hour of electricity,
which makes coal a very efficient energy source.
But some may argue that the negative impact it has on the environment outweighs its efficiency.
-The top producer of coal in the world is China.
-These are close to 600 coal power plants in the USA.
-Canaries continued to be used in coal mines to warn miners of dangerous gases until 1986 when electronic detectors replaced them.
-Burning coal can cause or worsen various health issues due to air pollution, such as asthma.
-Coal provides jobs for people both directly and indirectly: 760,000+ jobs were created in the USA from coal
Full transcript