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Is Oil Evil?
PT.1 Is my personal consumption of oil part of the problem?
When I was new in America, I walked with my mother in summer time. To my surprise, I found that more than two cars parking outside most of the houses. I asked my mom, ”Do they have a party?” Mom said, “No, they are their own cars.” I thought they might be very rich. Later I realized it was very common for a family to own more than two cars. Two of my neighbors have three cars respectively even though only two persons live in their houses! My family also has two cars, one is a SUV. Every two weeks we have to commutate between Milwaukee and Detroit. Each trip consumes about 50 gallons of oil. To add up, we will eat up 1300 gallons of oil in one year by commuting alone. What a scary number! So I admit my personal consumption of oil is part of the problem.
I hate to be part of the problem but I have no other choices. One of the most important reasons is the poor public transportation, especially in Michigan. We have no subway, no trolley, no train at all! And the number of buses is like camels in the vast desert. We have to go to school or work every day, do we have any options except using personal cars? Well, we can buy hybrid cars, we can carpool, but personal efforts are far not enough to change the situation. I think the government and industries should do something.
Reflecting my beautiful life in China, I was happy to ride bus No.743 to school and back home every day. It comes every 5 minutes. If I missed the bus, I had other 3 choices. It only costs 20 cents in Chinese RMB one way. It is super cheap. Just before I left Beijing September, a new subway line was being built to connect my area to downtown Beijing and everywhere else. The public transportation network in each city is like a spider web in China. So the personal car is not a necessity. Can U.S. learn something from other countries?
Ming C.
9 December 2007
Beijing subway system
PT.2 What impact does oil have on our environment?
As you all may know, oil has a major affect on our environment today. Whether it may be the gas prices rising becuase there is a higher demand for barrels or oil spills in the oceans harming the lives of the marine animals. As you can see in the next dated presented, the number of oil spills is the greatest in the U.S and it has also been increasing instead of decreasing throughout the years.
So is there a way that us humans can prevent these oil spills from happening? To tell you all the trut, most of the oil spill accidents are caused by human mistakes. Not all though are caused by mistakes, though. Some oil spills are intentional. Caused by either terrorists or careless procedures. There are also oil spills caused by natural disaster such as earthquakes and hurricanes. But these oil spills are on land and the ones on water provide a thick layer called the oil slick which makes the animals very defensive and they are exposed to very high intensifying chemical which poison the bodies and often kill the creatures.
Oil Spill:
Affected Animals:
So as you can now probably see, oil is affective in not only gas prices which are like a roler coster gone wild, but also a life hazard to the creatures of the earth. Help us save our planet. Help us help them.
Elizabeth Y.
15 December 2007
PT.3 Are there any viable energy alternatives?
Of course there are many different viable energy alternatives.
SOLAR ENERGY
The sun has produced energy for billions of years. Solar energy is the sun’s rays (solar radiation) that reach the earth. Solar energy
can be converted into other forms of energy, such as heat and electricity. In
the 1830s, the British astronomer John Herschel used a solar thermal collector box (a device that absorbs sunlight to collect heat) to
cook food during an expedition to Africa. Today, people use the sun's energy
for lots of things.
The major disadvantages of solar energy are:
- The amount of sunlight that arrives at the earth's surface is not constant. It depends on location, time of day, time of year, and
- weather conditions.
- the energy at a useful rate.
Photovoltaic cell:
Photovoltaic energy is the conversion of sunlight into electricity. A photovoltaic cell, commonly called a solar cell or PV, is the technology
used to convert solar energy directly into electrical power. A photovoltaic c
ell is a non mechanical device usually made from silicon alloys.
(learn more about the history of photovaltaic cells).
Some advantages of photovoltaic systems are:
- Conversion from sunlight to electricity is direct, so that bulky mechanical generator systems are unnecessary.
- PV arrays can be installed quickly and in any size required or allowed.
- The environmental impact is minimal, requiring no water for system cooling and
GEOTHERMAL ENERGY
Geothermal energy is generated in the earth's core, about 4,000 miles below the surface. Temperatures hotter than the sun's surface
are continuously produced inside the earth by the slow decay of radioactive
particles, a process that happens in all rocks. The earth has a number of different layers:
· The core itself has two layers: a solid iron core and an outer core made of very hot melted rock, called magma.
· The mantle which surrounds the core and is about 1,800 miles thick. It is made up of magma and rock.
· The crust is the outermost layer of the earth, the land that forms the continents and ocean floors. It can be three to five miles
thick under the oceans and 15 to 35 miles thick on the continents.
(See Uses of Geothermal Energy )
Most geothermal reservoirs are deep underground with no visible clues showing above ground.
Uses:
· 1) Direct Use and District Heating Systems which use hot water from springs or reservoirs near the surface.
2) Electricity generation in a power plant requires water or steam at very high temperature (300 to 700 degrees Fahrenheit).
Geothermal power plants are generally built where geothermal reservoirs a
re located within a mile or two of the surface.
3) Geothermal heat pumps use stable ground or water temperatures near the earth's surface to control building temperatures
above ground.
The direct use of hot water as an energy source has been happening since ancient times. The Romans, Chinese, and Native Americans
used hot mineral springs for bathing, cooking and heating. Today, many
hot springs are still used for bathing, and many people believe the hot,
mineral-rich waters have natural healing powers.
WIND ENERGY
The Sun heats our atmosphere unevenly, so some patches become warmer than others.
These warm patches of air rise, other air blows in to replace them - and we feel a wind blowing.
We can use the energy in the wind by building a tall tower, with a large propellor on the top.
The wind blows the propellor round, which turns a generator to produce electricity.
We tend to build many of these towers together, to make a "wind farm" and produce more electricity.
The more towers, the more wind, and the larger the propellors, the more electricity we can make.
It's only worth building wind farms in places that have strong, steady winds, although boats and caravans increasingly have small wind
generators to help keep their batteries charged.
(See also: www.fuelfromthewind.com)
NUCLEAR ENERGY
Nuclear power plants provide about 17 percent of the world's electricity. Some countries depend more on nuclear power for electricity
than others. In France, for instance, about 75 percent of the
electricity is generated from nuclear power, according to the International Atomic Energy Agency. In the United States, nuclear power
supplies about 15 percent of the electricity overall, but some s
tates get more power from nuclear plants than others. There are more than 400 nuclear power plants around the world, with more than
100 in the United States.
Nuclear power is possibly the most contentious and emotive of all methods of energy production, due to the nature of the material
involved and long term consequences of accidents.
TIDAL POWER
The tide moves a huge amount of water twice each day, and harnessing it could provide a great deal of energy. Only around 20 sites
in the world have been identified as possible tidal power stations.
A huge dam (called a "barrage") is built across a river estuary. When the tide goes in and out, the water flows through tunnels in the dam.
The ebb and flow of the tides can be used to turn a turbine, or it can be used to push air through a pipe, which then turns a turbine. Large
lock gates, like the ones used on canals, allow ships to pass.
H2 POWER
This type of power is the most green power in the world. The theory behind it is 2H2 + O2 = 2H2 O . It has no polution at all. The water it produces can be drank.
Fuel cell technology generating H2 power in small vehicie
Fuel cell technology generating H2 power in big vehicie
I have seen these buses in Beijing this summer. It looks pretty nice. Unfortunatly, I have never ridden such bus.
(For more information: www.silveradogreenfuel.com/ourfuel/technology)
12 December 2007
PT4 Is there a connection between oil and violence in the Middle East?
Truth be told, anyone can answer this questions. The answer is yes! Although this answer to this question may seem fairly self explanatory, there is some thinking to be done. The U.S. takes oil from the Middle East becuase they have oil, and we need the oil. Simple, but sometimes the U.S. goes too far and the government seeks any way to go into the Middle East and make matters worse.
"Oil hits $76 a barrel as violence in Middle East escalates" by: Brad Foss.
This direct system that needs to be put to an end. The economy runs on money, of you really think about it. THere is absolutly nothing that is free and nothing will ever come free. There is always a price to be paid. Whether it is with the lives of our soilders in Iraq, or with an innocent citizens' money for gas to pay so their car can run properly.
America Today:
If our government wants something it has to earn it, like the rest of us do. There is no aboslutle reason as why the U.S. needs to immediatly make accusations of some sort to an extent that invasion of privacy for other countries is the only outcome.
There should be compromise in the world where fair trade exists. As for now, we are stuck with deliberation on war and a situation between countries that does not seem as though it is not going to end very soon.
Elizabeth Y.
15 December 2007
Sources:
-
http://www.eia.doe.gov/kids/energyfacts/sources/renewable/solar.html#fromthesun
-
http://www.cqbus.net/?action-viewthread-tid-6958 (in Chinese)
Contributors:
Ming C. & Elizabeth Y.
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