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A
satellite image of North Korea’s Yongbyon nuclear facility
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There
has been much talk recently regarding the possession or commission
of nuclear reactors by certain countries. The reactivation of
North Korea’s nuclear reactor at Yongbyon has been causing a
great deal of apprehension lately. The commission of Iran’s
first nuclear reactor is continuing despite steady criticism by
the United States.
There
are more than 440 commercial nuclear reactors around the world and
another 30 under construction. 31 countries, including the
nuclear superpowers (USA, Federal Russia, France, Britain and
China), own commercial nuclear reactors. Nuclear power
provides over 16% of the world's electricity, almost 24% of the
electricity in OECD countries, and 35% in the EU. 77% of
France’s electricity is provided by nuclear reactors, the
remainder being hydroelectric. In Japan, which has little
coal and no oil, nuclear power provides nearly 30% of its
electrical energy needs. Australia, which has abundant and
accessible domestic coal resources does not own any nuclear power
plants but owns a research plant. Most of the planned
reactors will be constructed in Asia due to increased electricity
demands due to its fast growing economies. According to the
Uranium Information Centre, fifteen countries depend on nuclear
power for at least a quarter of their electricity. France
and Lithuania get around three quarters of their power from
nuclear energy, while Belgium, Bulgaria, Hungary, Japan, Slovakia,
South Korea, Sweden, Switzerland, Slovenia and Ukraine get one
third or more.
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Nuclear
bomb
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There
are two types of nuclear reactors: research reactors and power
reactors. Research reactors are used for scientific
research, and for the production of isotopes for medicinal and
industrial purposes. These types of reactors are not used
for energy production. There are 284 research reactors found
in 56 countries around the world. Power
reactors
are used to generate electricity. In addition to the
previous uses, nuclear reactors are also used as nuclear weapons
production facilities in countries that possess nuclear military
programs. The first large-scale commercial nuclear power
plant was commissioned in 1957 in the USA.
Nuclear
reactors work on the principle of nuclear fission. During nuclear
fission, the nuclei of atoms are split which leads to the release
of heat energy. Uranium-235 is the main fuel used in nuclear
reactors; plutonium-239 can also be used. The nuclear
fission of uranium atoms can be achieved by shooting neutrons at
them. As some of the atoms are being split they release
neutrons, and when these neutrons strike other atoms they cause
them to split as well, which releases even more neutrons. This
causes a chain reaction that generates huge amounts of heat
energy. The rate of nuclear fission in the reactor is
controlled using ‘control rods’ which absorb some of the
released neutrons. The rods allow the safe management and
regulation of the fission process. A water-cooling system is
used to remove the excess heat produced during the process and the
generated steam is used to drive the turbines that generate the
electricity. The main supply countries of uranium are
Canada, the United States, South Africa, Australia, and Nigeria.
There
are several advantages of nuclear energy over other forms of
energy:
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The
amount of nuclear fuel required to produce large amounts of
electric energy is much less than the amount of coal or oil
needed to generate the same amount of energy. For
example, one ton of uranium would generate more energy than
several million barrels of oil or several million tons of
coal. Solar energy would also be significantly more costly
than nuclear energy if it were to be relied upon for most of
the world’s energy.
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Well-operated
nuclear power plants produce the least amount of waste when
compared to any other energy generating process. No harmful
gases are expelled into the air such as CO2, nitrogen oxide
and sulphur dioxide, which cause global warming, acid rain and
smog.
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Uranium
ore is an abundant, low volume, easily extracted and
transported fuel source, whereas the Earth has limited
supplies of coal and oil. Nuclear power plants could
still supply energy well after coal and oil supplies become
insufficient.
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Nuclear
power plants take up relatively small areas of land for as
compared to solar and wind farms. “To build the equivalent
of a 1,000-megawatt nuclear plant, a solar park would have to
be larger than 35,000 acres, and a wind farm would have to be
150,000 acres or larger. By contrast, the Millstone Units 2
and 3 nuclear power plants in Connecticut have an installed
capacity of over 1,900 megawatts of power on a 500-acre site
designed for three nuclear plants” (Nuclear Regulatory
Commission).
Disadvantages
of Nuclear Energy
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A
partial nuclear meltdown occurred in the Three Mile Island nuclear
reactor in 1979
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The
main disadvantage of using nuclear energy is that highly
radioactive wastes are produced in the process. After most
of the usable uranium has fissioned, it is called spent fuel.
Spent fuel is removed from the reactor and stored in cooling pools
at the reactor site, which absorb the heat and reduce the
radioactivity. The re-processing of spent fuel for the
recovery of unfissioned uranium and plutonium leads to the
production of high-level radioactive waste (HLW). After
re-processing, the recovered uranium and plutonium can be used as
fuel for the reactor. Spent fuel is re-processed routinely
at defence program reactors for use in the production of nuclear
weapons, and according to the EPA, defence-related HLW comprises
greater than ninety-nine percent of the volume of HLW in the USA.
France, Belgium, Russia, and the UK all own reprocessing plants
and Japan uses fuel reprocessed in Europe. According to the
International Atomic Energy Agency (IAEA), at the end of 1997,
more than 130,000 tonnes of spent fuel from power reactors were
estimated to be stored worldwide containing about 1000 tonnes of
plutonium. Certain elements of HLW and spent fuel such as
plutonium are highly radioactive and remain so for thousands of
years. There is currently no safe disposal system for these
wastes. Projected plans for the disposal and storage of HLW
do not ensure adequate protection of ground water or individuals
from radioactive contamination.
A
number of accidents have occurred involving nuclear reactors.
In 1979, a partial nuclear meltdown occurred at the Three Mile
Island nuclear reactor in Pennsylvania. A nuclear meltdown
occurs when the fission reaction goes out of control leading to an
explosion, with the release of huge amounts of radiation.
The radiation in the Three Mile Island reactor meltdown was
contained within the structure and there were no deaths, however a
similar incident that occurred in 1986 at the Chernobyl nuclear
power plant in Russia was not so fortunate. 31 people were
killed and hundreds of thousands of people were exposed to
radiation. The harmful effects of radiation may continue to
effect future generations.
Nuclear
Facilities May Have Dual Use
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Many
children were deformed due to Chernobyl’s nuclear disaster
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Commercial
nuclear reactors could be used for nuclear weapons research and
for the production of nuclear weapons. Different plutonium
isotopes are produced in the reactor. Plutonium-239 is
produced when Uranium-238 in the reactor absorbs a neutron and
then quickly decays to plutonium. Nuclear reactors that are
run specifically for creating nuclear weapons use this
Plutonium-239, since it is the ideal isotope of plutonium for this
purpose. In commercial reactors, other isotopes of plutonium
such as Pu-240, Pu-241 and Pu-238 are produced since the reactor
fuel is subjected to longer periods of neutron radiation.
These other isotopes are not ideal for weapons production, however
they can still be used to produce a nuclear explosive. The
explosive would not be as stable as that produced from weapons
grade plutonium and could blow up prematurely, however even if
that was the case the explosive yield would have at least a radius
of destruction roughly one-third that of the Hiroshima weapon,
making it a potentially fearsome explosive (National Academy of
Sciences).
As
for now, the extension of nuclear power depends considerably on
politics, and these politics have been very different in different
countries. Which countries wish to own nuclear reactors or
need them does not seem to be the key issue in many cases.
Sources:
Aisha El-Awady
has a bachelor’s degree in medicine from Cairo
University and is currently working as instructor of
Parasitology in the Faculty of Medicine. She may be
contacted at aawady@islam-online.net.
