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The Pros And Cons of Nuclear Energy
"1. Little Pollution
As demand for electricity soars, the pollution produced
from fossil fuel-burning plants is heading towards dangerous levels. Coal, gas and oil burning power plants are already responsible
for half of America's air pollution. Burning coal produces carbon dioxide, which depletes the protection of the ozone. The
soft coal, which many power plants burn, contains sulfur When the gaseous byproducts are absorbed in clouds, precipitation
becomes sulfuric acid.. Coal also contains radioactive material. A coal-fired power plant emits more radiation into
the air than a nuclear power plant. The world's reserves of fossil fuels are running out. The sulfurous
coal which many plants use is more polluting than the coal that was previously used. Most of the anthracite, which plants
also burn, has been used up. As more soft coal is used, the amount of pollution will increase. According to estimates, fossil
fuels will be burned up within fifty years. There are large reserves of uranium, and new breeder reactors can produce
more fuel than they use. Unfortunately this doesn't mean we can have an endless supply of fuel Breeder reactors need a feedstock
of uranium and thorium, so when we run out of these two fuels (in about 1000 years), breeder reactors will cease to be useful.
This is still a more lengthy solution to the current burning of coal, gas, and oil.
2. Reliability
Nuclear power plants need little fuel, so they are
less vulnerable to shortages because of strikes or natural disasters. International relations will have little effect on the
supply of fuel to the reactors because uranium is evenly deposited around the globe. One disadvantage of uranium mining is
that it leaves the residues from chemical processing of the ore, which leads to radon exposure to the public. These effects
do not outweigh the benefits by the fact that mining uranium out of the ground reduces future radon exposures. Coal burning
leaves ashes that will increase future radon exposures. The estimates of radon show that it is safer to use nuclear fuel than
burn coal. Mining of the fuel required to operate a nuclear plant for one year will avert a few hundred deaths, while the
ashes from a coal-burning plant will cause 30 deaths.
3. Safety
Safety is both a pro and con, depending on which way
you see it. The results of a compromised reactor core can be disastrous, but the precautions that prevent this from happening
prevent it well. Nuclear power is one the safest methods of producing energy. Each year, 10,000 to 50,000 Americans die from
respiratory diseases due to the burning of coal, and 300 are killed in mining and transportation accidents. In contrast, no
Americans have died or been seriously injured because of a reactor accident or radiation exposure from American nuclear power
plants. There are a number of safety mechanisms that make the chances of reactor accidents very low. A series of barriers
separates the radiation and heat of the reactor core from the outside. The reactor core is contained within a 9-inch thick
steel pressure vessel. The pressure vessel is surrounded by a thick concrete wall. This is inside a sealed steel containment
structure, which itself is inside a steel-reinforced concrete dome four feet thick. The dome is designed to withstand extremes
such as earthquakes or a direct hit by a crashing airliner. There is also a large number of sensors that pick up increases
in radiation or humidity. An increase in radiation or humidity could mean there is a leak. There are systems that control
and stop the chain reaction if necessary. An Emergency Core Cooling System ensures that in the event of an accident there
is enough cooling water to cool the reactor.
Cons -
1. Meltdowns
If there is a loss of coolant water in a fission reactor,
the rods would overheat. The rods that contain the uranium fuel pellets would dissolve, leaving the fuel exposed. The temperature
would increase with the lack of a cooling source. When the fuel rods heat to 2800°C, the fuel would melt, and a white-hot
molten mass would melt its way through the containment vessels to the ground below it. This is a worst case scenario, as there
are many precautions taken to avoid this. Emergency water reservoirs are designed to immediately flood the core in the case
of sudden loss of coolant. There are normally multiple sources of water to draw from, as the low pressure injection pumps,
containment spray system, and refueling pumps are all potentially available, and all draw water from different sources. The
disaster at Three Mile Island was classified as a partial meltdown, caused by the failure to supply coolant to the core. Although
the core was completely destroyed, the radioactive mass never penetrated the steel outlining the containment structure. Several
feet of special concrete, a standard precaution, was capable of preventing leakage for several hours, giving operators enough
time to fix the flooding system of the reactor core. The worst case of a nuclear disaster was in 1986 at the Chernobyl facility
in the Ukraine. A fire ripped apart the casing of the core, releasing radioactive isotopes into the atmosphere. Thirty-one
people died as an immediate result. And estimated 15,000 more died in the surrounding area after exposure to the radiation.
Three Mile Island and Chernobyl are just examples of the serious problems that meltdowns can create.
2. Radiation
Radiation doses of about 200 rems cause radiation sickness,
but only if this large amount of radiation is received all at once. The average person receives about 200 millirems a year
from everyday objects and outer space. This is referred to as background radiation. If all our power came from nuclear plants we would receive an extra 2/10 of a millirem a year. The three major effects of radiation
(cancer, radiation sickness and genetic mutation) are nearly untraceable at levels below about 50 rems. In a study of 100,000
survivors of the atomic bombs dropped on Hiroshima and Nagasaki, there have been 400 more cancer deaths than normal, and there
is not an above average rate of genetic disease in their children. During the accident at Three Mile Island in America, people
living within a 50 mile radius only received an extra 3/10 of one percent of their average annual radiation. This was because
of the containment structures, the majority of which were not breached. The containment building and primary pressure vessel
remained undamaged, fulfilling their function.
3. Waste Disposal
The byproducts of the fissioning
of uranium-235 remains radioactive for thousands of years, requiring safe disposal away from society until they lose their
significant radiation values. Many underground sites have been constructed, only to be filled within months. Storage facilities
are not sufficient to store the world’s nuclear waste, which limits the amount of nuclear fuel that can be used per
year. Transportation of the waste is risky, as many unknown variables may affect the containment vessels. If one of these
vessels were compromised, the results may be deadly. " members.tripod.com/funk_phenomenon/nuclear/procon.htm
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