Executive Summary:
A
nuclear power plant harnesses the energy inside atoms themselves and converts
this to electricity. A nuclear power plant uses controlled nuclear fission.
Nuclear energy is energy in the nucleus (core) of an atom. Atoms are tiny
particles that make up every object in the universe. There is enormous energy
in the bonds that hold atoms together. Nuclear energy can be used to make
electricity. But first the energy must be released. It can be released from
atoms in two ways: nuclear fusion and nuclear fission. . Nuclear power plants
use this energy to produce electricity. In nuclear fusion, energy is released
when atoms are combined or fused together to form a larger atom. The fuel most
widely used by nuclear plants for nuclear fission is uranium. Nuclear plants
use a certain kind of uranium, referred to as U-235. This kind of uranium is
used as fuel because its atoms are easily split apart. Just as there are
different approaches to designing and building airplanes and automobiles,
engineers have developed different types of nuclear power plants. Two types are
used: boiling-water reactors and pressurized-water reactors. In a boiling-water
reactor, the water heated by the reactor core turns directly into steam in the
reactor vessel and is then used to power the turbine-generator. In a
pressurized-water reactor, the water heated by the reactor core is kept under
pressure so that it does not turn to steam at all — it remains liquid. A
typical nuclear reactor has a few main parts. Inside the "core" where
the nuclear reactions take place are the fuel rods and assemblies, the control
rods, the moderator, and the coolant. Outside the core are the turbines, the
heat exchanger, and part of the cooling system. The fuel assemblies are
collections of fuel rods. These rods are each about 3.5 meters (11.48 feet)
long. They are each about a centimeter in diameter. These are grouped into
large bundles of a couple hundred rods called fuel assemblies, which are then
placed in the reactor core. Inside each fuel rod are hundreds of pellets of
uranium fuel stacked end to end. Also in the core are control rods. These rods
have pellets inside that are made of very efficient neutron capturers. An
example of such a material is cadmium. These control rods are connected to
machines that can raise or lower them in the core. When they are fully lowered
into the core, fission cannot occur because they absorb free neutrons. However,
when they are pulled out of the reactor, fission can start again anytime a
stray neutron strikes a 235U atom, thus releasing more neutrons, and starting a
chain reaction. Another component of the reactor is the moderator. As opposed
to current light water reactors which use uranium-235 (0.7% of all natural
uranium), fast breeder reactors use uranium-238 (99.3% of all natural uranium).
The most important waste stream from nuclear power plants is spent fuel. A large
nuclear reactor produces 3 cubic meters (25–30 tones) of spent fuel each year.
It is primarily composed of unconverted uranium as well as significant
quantities of transuranic actinides (plutonium and curium, mostly). In addition, about 3%
of it is made of fission products. Spent fuel is highly radioactive and needs
to be handled with great care and forethought. However, spent nuclear fuel
becomes less radioactive over the course of thousands of years of time. After
about 5 percent of the rod has reacted the rod is no longer able to be used.
Today, scientists are experimenting on how to recycle these rods to reduce
waste. In the meantime, after 40 years, the radiation flux is 99.9% lower than it was the moment the spent fuel was
removed, although still dangerously radioactive. Spent fuel rods are stored in shielded basins of water (spent fuel pools),
usually located on-site. The nuclear industry also produces a huge volume of
low-level radioactive waste in the form of contaminated items like clothing,
hand tools, water purifier resins, and (upon decommissioning) the materials of
which the reactor itself is built. In the United States, the Nuclear Regulatory
Commission has
repeatedly attempted to allow low-level materials to be handled as normal
waste: land filled, recycled into consumer items, et cetera. Most low-level
waste releases very low levels of radioactivity and is only considered
radioactive waste because of its history. Unlike fossil fuel-fired power
plants, nuclear power plants produce no air pollution or carbon dioxide. India and Pakistan
generate 2 per cent of their electricity from nuclear reactors, while South Korea
gets 29 per cent of its electricity from nuclear plants, Japan 25, United States
20, Russia
17 and United Kingdom
14 per cent. Bangladesh wants to set up first
nuclear power plant at Rooppur in Pabna and the land was acquired in 1963. Bangladesh
would need at least 500 nuclear scientists for a 1,000 MW nuclear power plant
for its operation and maintenance after its installation.
Introduction:
There
are many different kinds of nuclear power plants, and we will discuss a few
important designs in this text. A nuclear power plant harnesses the energy
inside atoms themselves and converts this to electricity. This electricity is
used by all of us. By now, we should have an idea of the fission process and
how it works. A nuclear power plant uses controlled nuclear fission. In this
section, we will explore how a nuclear power plant operates and the manner in
which nuclear reactions are controlled. Just as many conventional thermal power stations generate
electricity by harnessing the thermal
energy released from burning fossil fuels,
nuclear power plants convert the energy released from the nucleus of an atom,
typically via nuclear fission.
Energy from Atoms:
Nuclear energy is energy in the nucleus (core) of an atom.
Atoms are tiny particles that make up every object in the universe. There is
enormous energy in the bonds that hold atoms together. Nuclear energy can be
used to make electricity. But first the energy must be released. It can be
released from atoms in two ways: nuclear fusion and nuclear fission.
Nuclear explosion
In nuclear fission, atoms are split apart to form smaller
atoms, releasing energy. Nuclear power plants use this energy to produce electricity.
In nuclear fusion, energy is released when atoms are combined or fused together
to form a larger atom. This is how the sun produces energy. Fusion is the
subject of ongoing research, but it is not yet clear that it will ever be a
commercially viable technology for electricity generation.
Nuclear Fuel: (Uranium)
Uranium Ore
The fuel most widely used by nuclear plants for nuclear
fission is uranium. Uranium is nonrenewable, though it is a common metal found
in rocks all over the world. Nuclear plants use a certain kind of uranium,
referred to as U-235. This kind of uranium is used as fuel because its atoms
are easily split apart. Though uranium is quite common, about 100 times more
common than silver, U-235 is relatively rare. Most U.S. uranium is mined in the Western United States.
Nuclear Fission
Once uranium is mined, the U-235 must be extracted and
processed before it can be used as a fuel. During nuclear fission, a small
particle called a neutron hits the uranium atom and splits it, releasing a
great amount of energy as heat and radiation. More neutrons are also released.
These neutrons go on to bombard other uranium atoms, and the process repeats
itself over and over again. This is called a chain reaction.
Chain Reaction
Nuclear power:
Nuclear power generally refers to electrical power from
controlled (ie, non-explosive) nuclear
reactions. Commercial plants in use to date use nuclear
fission reactions. Electric utility reactors heat water to produce
steam, which is then used to generate electricity.
In 2007, 14% of the world's electricity came from nuclear power, despite
concerns about safety and radioactive waste management. More
than 150 naval vessels using nuclear propulsion have been built. Nuclear
reactions are widely believed to be safer than fission and appear potentially
viable, though technically quite difficult. Fusion
power has been under intense theoretical and experimental investigation for
many years. Both fission and fusion appear promising for some space propulsion
applications in the mid- to distant-future, using low thrust for long durations
to achieve high mission velocities. Radioactive decay has been
used on a relatively small (few kW) scale, mostly to power space missions and
experiments.
Diagram: Basic function
Chart: Electricity generation
As of 2005, nuclear power provided 2.1% of the world's
energy and 15% of the world's electricity, with the U.S., France, and Japan together accounting for 56.5% of
nuclear generated electricity. In 2007, the IAEA reported there were
439 nuclear power reactors in operation in the world, operating in
31 countries. In 2007, nuclear power's share of global electricity
generation dropped to 14%. According to the International Atomic Energy Agency,
the main reason for this was an earthquake in western Japan on 16 July 2007, which shut
down all seven reactors at the Kashiwazaki-Kariwa Nuclear Power
Plant. There were also several other reductions and "unusual
outages" experienced in Korea
and Germany.
Also, increases in the load factor for the current fleet of reactors appear to
have platitude. The United
States produces the most nuclear energy,
with nuclear power providing 19% of the electricity it consumes, while France produces
the highest percentage of its electrical energy from nuclear reactors—78% as of
2006. In the European Union as a whole, nuclear energy provides
30% of the electricity. Nuclear energy policy differs between
European Union countries, and some, such as Austria, Estonia, and Ireland, have no
active nuclear power stations. In comparison, France has a large number of these
plants, with 16 multi-unit stations in current use. In the US, while the
Coal and Gas Electricity industry is projected to be worth $85 billion by 2013,
Nuclear Power generators are forecast to be worth $18 billion. Many military
and some civilian (such as some icebreaker)
ships use nuclear marine propulsion, a form of nuclear propulsion. A few space vehicles have
been launched using full-fledged nuclear
reactors: the Soviet RORSAT series and the American SNAP-10A. International
research is continuing into safety improvements such as passively
safe plants, the use of nuclear
fusion, and additional uses of process heat such as hydrogen production (in support of a hydrogen
economy), for desalinating sea water, and for use in district
heating systems.
History:
As the father of nuclear
physics, Ernest Rutherford is credited with splitting the atom in 1917. His team in England
bombarded nitrogen with naturally occurring alpha particles from radioactive
material and observed a proton emitted with energy higher than the alpha
particle. In 1932 two of his students John
Cockcroft and Ernest Walton, working under Rutherford's direction,
attempted to split the atomic nucleus by entirely artificial means, using a
particle accelerator to bombard lithium with protons, thereby producing two helium nuclei.
After James Chadwick discovered the neutron in 1932, nuclear
fission was first experimentally achieved by Enrico
Fermi in 1934 in Rome,
when his team bombarded uranium with neutrons.
Uranium Ore
In 1938, German
chemists Otto
Hahn and Fritz Strassmann, along with Austrian physicists Lise
Meitner and Meitner's nephew, Otto Robert Frisch, conducted experiments with
the products of neutron-bombarded uranium. They determined that the relatively
tiny neutron split the nucleus of the massive uranium atoms into two roughly
equal pieces, which was a surprising result. Numerous scientists, including Leo Szilard
who was one of the first, recognized that if fission reactions released
additional neutrons, a self-sustaining nuclear chain reaction could result.
This spurred scientists in many countries (including the United States,
the United Kingdom,
France,
Germany,
and the Soviet Union) to petition their
government for support of nuclear fission research. In the United States,
where Fermi and Szilard had both emigrated, this led to the creation of the
first man-made reactor, known as Chicago
Pile-1, which achieved criticality on December 2, 1942. This work became part of the Manhattan
Project, which built large reactors at the Hanford
Site (formerly the town of Hanford, Washington) to breed plutonium for
use in the first nuclear weapons, which were used on the cities of Hiroshima and
Nagasaki. A
parallel uranium enrichment effort also was pursued. After World War
II, the fear that reactor research would encourage the rapid spread of
nuclear weapons and technology, combined with what many scientists thought
would be a long road of development, created a situation in which the
government attempted to keep reactor research under strict government control
and classification. In addition, most reactor research centered on purely
military purposes. Actually, there were no secrets to the technology. There was
an immediate arms and development race when the United States military refused to
follow the advice of its own scientific community to form an international
cooperative to share information and control nuclear materials. By 2006, things
have come full circle with the Global Nuclear Energy Partnership (see below.) Electricity
was generated for the first time by a nuclear reactor on December 20, 1951 at the EBR-I experimental
station near Arco, Idaho, which initially produced about 100 kW
(the Arco Reactor was also the first to experience partial meltdown,
in 1955). In 1952, a report by the Paley Commission (The President's Materials
Policy Commission) for President Harry
Truman made a "relatively pessimistic" assessment of nuclear
power, and called for "aggressive research in the whole field of solar
energy."[17]
A December 1953 speech by President Dwight
Eisenhower, "Atoms for Peace," emphasized the useful
harnessing of the atom and set the U.S. on a course of strong
government support for international use of nuclear power.
Early years:
Diagram: Nuclear processing
plant.
Calder Hall nuclear power station in the United
Kingdom was the world's first nuclear power station to produce electricity
in commercial quantities.
Diagram: Nuclear power plant
The Shipping port Atomic Power Station
in Shipping port, Pennsylvania was the
first commercial reactor in the USA
and was opened in 1957. On June
27, 1954, the USSR's Obninsk Nuclear Power Plant became the
world's first nuclear power plant to generate electricity for a power grid,
and produced around 5 megawatts of electric power. Later in 1954, Lewis
Strauss, then chairman of the United States Atomic Energy
Commission (U.S. AEC, forerunner of the U.S. Nuclear Regulatory Commission and the
United States Department of Energy)
spoke of electricity in the future being "too cheap to meter." The
U.S. AEC itself had issued far more conservative testimony regarding nuclear
fission to the U.S. Congress only months before, projecting that "costs
can be brought down ... about the same as the cost of electricity from
conventional sources..." Strauss may have been making vague reference to
hydrogen fusion - which was secret at the time - rather than uranium fission,
but whatever his intent Strauss's statement was interpreted by much of the
public as a promise of very cheap energy from nuclear fission. Significant disappointment
would develop later on, when the new nuclear plants did not provide energy
"too cheap to meter." In 1955
the United
Nations' "First Geneva Conference", then the world's largest
gathering of scientists and engineers, met to explore the technology. In 1957 EURATOM was
launched alongside the European Economic Community (the latter
is now the European Union). The same year also saw the launch of the International Atomic Energy Agency
(IAEA). The world's first commercial nuclear power station, Calder Hall in Sellafield,
England was opened in 1956
with an initial capacity of 50 MW (later 200 MW). The first commercial nuclear
generator to become operational in the United States was the Shipping port Reactor (Pennsylvania,
December, 1957). One of the first organizations to develop nuclear power was
the U.S. Navy, for the purpose of propelling submarines
and aircraft carriers. It has a good record in nuclear
safety, perhaps because of the stringent demands of Admiral Hyman
G. Rickover, who was the driving force behind nuclear marine propulsion as
well as the Shipping port Reactor. The U.S. Navy has operated more nuclear
reactors than any other entity, including the Soviet Navy,
with no publicly known major incidents. The first nuclear-powered submarine, USS Nautilus (SSN-571), was put to sea in
December 1954. Two U.S.
nuclear submarines, USS Scorpion and USS Thresher, have been lost at sea. These
vessels were both lost due to malfunctions in systems not related to the
reactor plants. Also, the sites are monitored and no known leakage has occurred
from the onboard reactors. The United States Army also had a nuclear power program, beginning in
1954. The SM-1 Nuclear Power Plant, at Ft.
Belvoir, Va., was the
first power reactor in the US
to supply electrical energy to a commercial grid (VEPCO), in April 1957, before
shipping port. Enrico Fermi and Leó
Szilárd in 1955 shared U.S.
Patent 2,708,656 for the nuclear reactor, belatedly granted for the work
they had done during the Manhattan Project.
Types
of Reactor:
Types of Reactor
Just as there are different approaches to designing and
building airplanes and automobiles, engineers have developed different types of
nuclear power plants. Two types are used: boiling-water reactors and
pressurized-water reactors.
Boiling-Water Reactors:
In a boiling-water reactor, the water heated by the reactor
core turns directly into steam in the reactor vessel and is then used to power
the turbine-generator.
Diagram: Basic function
Pressurized-Water Reactors:
In a pressurized-water reactor, the water heated by the
reactor core is kept under pressure so that it does not turn to steam at all —
it remains liquid. This hot radioactive water flows through a piece of
equipment called a steam generator. A
steam generator is a giant cylinder with thousands of tubes in it that the hot
radioactive water can flow through and heat up. Outside these hot tubes in the
steam generator is no radioactive water (or clean water), which eventually
boils and turns to steam. The
radioactive water flows back to the reactor core, where it is reheated and then
sent back to the steam generator. The clean water may come from one of several
sources including oceans, lakes, or rivers.
Uranium Processed:
Uranium is nonrenewable, though it is a common metal found
in rocks all over the world. Uranium occurs in nature in combination with small
amounts of other elements. Nuclear plants use a certain kind of uranium, U-235,
as fuel because its atoms are easily split apart. Though uranium is quite
common, about 100 times more common than silver, U-235 is relatively rare. Economically
recoverable uranium deposits have been discovered principally in the western United States, Australia, Canada, Africa, and South America.
Once uranium is mined, the U-235 must be extracted and processed before it can
be used as a fuel. Mined uranium ore typically yields one to four pounds of
uranium concentrate (U3O8
or "yellowcake") per ton, or 0.05% to 0.20% U3O8.
Core
Uranium Preparation:
Uranium 235U will not be the
only isotope of uranium present in a nuclear reactor. In naturally occurring
uranium deposits, less than one percent of the uranium is 235U. The majority of
the uranium is 238U. 238U is not a fissile isotope of uranium. When 238U is
struck by a loose neutron, it absorbs the neutron into its nucleus and does not
fission. Thus, by absorbing loose neutrons, 238U can prevent a nuclear chain
reaction from occurring. This would be a bad thing because if a chain reaction
doesn't occur, the nuclear reactions can't sustain themselves, the reactor
shuts down, and millions of people are without electrical power. In order for a
chain reaction to occur, the pure uranium ore must be refined to raise the
concentration of 235U. This is called enrichment and is primarily accomplished
through a technique called gaseous diffusion. In this process, the uranium ore
is combined with fluorine to create a chemical compound called uranium
hexafluoride. The uranium hexafluoride is heated and vaporizes. The heated gas
is then pushed through a series of filters. Because some of the uranium
hexafluoride contains 238U and some contains 235U, there is a slight difference
in the weights of the individual molecules. The molecules of uranium
hexafluoride containing 235U are slightly lighter and thus pass more easily
through the filters. This creates a quantity of uranium hexafluoride with a
higher proportion of 235U. This is collected, the uranium is stripped from it,
and the result is an enriched supply of fuel. Usually, nuclear power plants use
uranium fuel that is about 4% 235U.
Diagram: Two major part of nuclear
power plant
Diagram: Inside of Nuclear Reactor
Parts of a Nuclear Reactor (PWR):
Fuel Assembly Containing a Number of Fuel Rods
 |
A typical nuclear reactor has a few main parts. Inside the
"core" where the nuclear reactions take place are the fuel rods and
assemblies, the control rods, the moderator, and the coolant. Outside the core
are the turbines, the heat exchanger, and part of the cooling system. The fuel
assemblies are collections of fuel rods. These rods are each about 3.5 meters
(11.48 feet) long. They are each about a centimeter in diameter. These are
grouped into large bundles of a couple hundred rods called fuel assemblies,
which are then placed in the reactor core. Inside each fuel rod are hundreds of
pellets of uranium fuel stacked end to end. Also in the core are control rods.
These rods have pellets inside that are made of very efficient neutron
capturers. An example of such a material is cadmium. These control rods are
connected to machines that can raise or lower them in the core. When they are
fully lowered into the core, fission can not occur because they absorb free
neutrons. However, when they are pulled out of the reactor, fission can start
again anytime a stray neutron strikes a 235U atom, thus releasing more
neutrons, and starting a chain reaction. Another component of the reactor is
the moderator. The moderator serves to slow down the high speed neutrons
"flying" all around the reactor core. If a neutron is moving too
fast, and thus is at a high-energy state, it passes right through the 235U
nucleus. It must be slowed down to be captured by the nucleus and to induce
fission. The most common moderator is water, but sometimes it can be another
material. The job of the coolant is to absorb the heat from the reaction. The
most common coolant used in nuclear power plants today is water. In actuality,
in many reactor designs the coolant and the moderator are one and the same. The
coolant water is heated by the nuclear reactions going on inside the core.
However, this heated water does not boil because it is kept at an extremely
intense pressure, thus raising its boiling point above the normal 100° Celsius.
The Inside of a Reactor Containment
Structure
One can see the heavy concrete walls from which the structure is made. Also, a fuel rod transportation canister is in the background (blue arrow). In front of that is the pit where the reactor core would normally reside (red arrow).  |
The heated water rises up and
passes through another part of the reactor, the heat exchanger. The
moderator/coolant water is radioactive, so it can not leave the inner reactor
containment. Its heat must be transferred to non-radioactive water, which can
then be sent out of the reactor shielding. This is done through the heat
exchanger, which works by moving the radioactive water through a series of
pipes that are wrapped around other pipes. The metallic pipes conduct the heat
from the moderator to the normal water. Then, the normal water (now in steam
form and intensely hot) moves to the turbine, where electricity is produced.
Three Mile
Island,
the Site of a Nuclear Accident
The steam towers are the large objects in the upper part of the picture. They do not actually house any reactors, and their only purpose is to cool water after it has passed through the turbines.  |
After the hot water has passed
through the turbine, some of its energy is changed into electricity. However,
the water is still very hot. It must be cooled somehow. Many nuclear power
plants used steam towers to cool this water with air. These are generally the
buildings that people associate with nuclear power plants. At reactors that do
not have towers, the clean water is purified and dumped into the nearest body
of water, and cool water is pumped in to replace it.
Basic Function
Reactor
Cold coolant:
After releasing its heat to the
steam generator, the cold coolant returns to the reactor.
Transfer of heat to water:
The coolant releases the heat
given off by the fission of uranium to the steam generator.
Water Pipes
Hot coolant:
The coolant extracts heat from
the fuel and carries it toward the steam generator.
Water turns into steam:
The hot coolant heats the water
of the generator and brings it to the boiling point.
Reactor:
Tightly sealed area where
fission of the fuel is carried out in a controlled manner to release heat.
Process
Containment building:
Concrete building used to
collect the radioactive steam from the reactor in the event of an accident.
Cooling Tower
Dousing water tank:
Vat that contains water to cool
the radioactive steam in the reactor in the event of an accident; this prevents
a rise in pressure.
Sprinklers:
Devices that are release water
to condense radioactive steam.
Safety valve:
Devices that are lower the
pressure inside the reactor by discharging the radioactive steam to the
containment building.
Valve
Fission of uranium fuel:
The nuclei of the atoms break
up; this frees neutrons and releases energy in the form of heat.
Production of electricity by the generator:
The generator produces
electricity through the movement of the rotor in the stator.
Heat production:
The fission of atoms releases
intense heat (between 575°F and 925°F), which is transmitted to the coolant.
Heat Transfer
Turbine shaft turns generator:
The rotational movement of the
turbine is transmitted to the generator’s rotor.
Generator
Coolant:
Liquid or gas (including heavy
water and carbon dioxide) that circulates inside the reactor; it harnesses and
transports the heat released during fission of the fuel.
Water into steam generator:
After passing through the
turbine, water produced by the condensation of the steam returns to the steam
generator.
Water cools the used steam:
Cooling of the steam from the
turbine is done with river or lake water.
Condensation of steam into water:
At the turbine outlet, the steam
cools and condenses into water.
Electricity transmission:
Using high-voltage lines to
transmit electricity over long distances reduces the strength of the current
and, as a result, energy losses.
Voltage increase:
At the outlet end of the power
plant, the transformer increases the voltage; this reduces energy losses during
transmission over long distances.
Meter
Steam pressure drives turbine:
Steam from the steam generator
turns the turbine runner, which is connected to the generator.
Turbine
Fuel:
Matter placed in the core of the
reactor that contains heavy atoms (uranium, plutonium); energy is extracted
from it by fission.
Moderator:
Substance (ordinary water, heavy
water, graphite) that slows the fast-moving neutrons emitted during fission to
increase the probability of new collisions.
Life
cycle:
Life Cycle
The Nuclear Fuel Cycle begins
when uranium is mined, enriched, and manufactured into nuclear fuel, (1) which
is delivered to a nuclear power plant. After usage in the power
plant, the spent fuel is delivered to a reprocessing plant (2) or to a final
repository (3) for geological disposition. In reprocessing 95% of spent fuel can be
recycled to be returned to usage in a power plant (4). A nuclear reactor is
only part of the life-cycle for nuclear power. The process starts with mining.
Uranium mines are underground, open-pit,
or in-situ leach
mines. In any case, the uranium ore is extracted, usually converted into a
stable and compact form such as yellowcake,
and then transported to a processing facility. Here, the yellowcake is
converted to uranium hexafluoride, which is then enriched using various techniques. At this
point, the enriched uranium, containing more than the natural 0.7% U-235, is
used to make rods of the proper composition and geometry for the particular
reactor that the fuel is destined for. The fuel rods will spend about 3
operational cycles (typically 6 years total now) inside the reactor, generally
until about 3% of their uranium has been fissional, then they will be moved to
a spent fuel
pool where the short lived isotopes generated by fission can decay
away. After about 5 years in a cooling pond, the spent fuel is radioactively
and thermally cool enough to handle, and it can be moved to dry storage casks
or reprocessed.
Conventional
fuel resources:
Fuel
Uranium
is a fairly common element in the Earth's crust. Uranium is
approximately as common as tin or germanium in Earth's crust, and is about 35 times more
common than silver.
Uranium is a constituent of most rocks, dirt, and of the oceans. The fact that
uranium is so spread out is a problem because mining uranium is only
economically feasible where there is a large concentration. Still, the world's
present measured resources of uranium, economically recoverable at a price of
130 USD/kg, are enough to last for "at least a century" at current
consumption rates. This represents a higher level of assured resources than is
normal for most minerals. On the basis of analogies with other metallic
minerals, a doubling of price from present levels could be expected to create
about a tenfold increase in measured resources, over time. However, the cost of
nuclear power lies for the most part in the construction of the power station.
Therefore the fuel's contribution to the overall cost of the electricity
produced is relatively small, so even a large fuel price escalation will have
relatively little effect on final price. For instance, typically a doubling of
the uranium market price would increase the fuel cost for a light water reactor
by 26% and the electricity cost about 7%, whereas doubling the price of natural
gas would typically add 70% to the price of electricity from that source. At
high enough prices, eventually extraction from sources such as granite and
seawater become economically feasible. Current light water reactors make relatively
inefficient use of nuclear fuel, fissioning only the very rare uranium-235
isotope. Nuclear reprocessing can make this waste
reusable and more efficient reactor designs allow better use of the available
resources.
Breeding:
As
opposed to current light water reactors which use uranium-235 (0.7% of all
natural uranium), fast breeder reactors use uranium-238 (99.3% of all natural
uranium). It has been estimated that there is up to five billion years’ worth
of uranium-238 for use in these power plants. Breeder technology has been used
in several reactors, but the high cost of reprocessing fuel safely requires
uranium prices of more than 200 USD/kg before becoming justified economically.
As of December 2005, the only breeder reactor producing power is BN-600 in Beloyarsk, Russia.
The electricity output of BN-600 is 600 MW Russia has planned to build another
unit, BN-800, at Beloyarsk nuclear power plant. Also, Japan's Monju reactor is planned
for restart (having been shut down since 1995), and both China and India intend to
build breeder reactors. Another alternative would be to use uranium-233 bred
from thorium
as fission fuel in the thorium fuel cycle. Thorium is about 3.5 times
as common as uranium in the Earth's crust, and has different geographic
characteristics. This would extend the total practical fissionable resource
base by 450%.Unlike the breeding of U-238 into plutonium, fast breeder reactors
are not necessary it can be performed
satisfactorily in more conventional plants. India has looked into this
technology, as it has abundant thorium reserves but little uranium.
Water:
Water Pipes
Like
all forms of power generation using steam turbines, nuclear power plants use
large amounts of water for cooling. At Sellafield,
which is no longer producing electricity, a maximum of 18,184.4 m³ a day
(over 4 million gallons) and 6,637,306 m³ a year (figures from the
Environment Agency) of fresh water from Waste Water
is still abstracted to use on site for various processes. As with most power
plants, two-thirds of the energy produced by a nuclear power plant goes into
waste heat (see Carnot cycle), and that heat is carried away
from the plant in the water (which remains uncontaminated by radioactivity).
The emitted water either is sent into cooling towers where it goes up and is
emitted as water droplets (literally a cloud) or is discharged into large
bodies of water — cooling ponds, lakes, rivers, or oceans. Droughts can pose a
severe problem by causing the source of cooling water to run out. The Palo Verde Nuclear Generating Station
near Phoenix, AZ
is the only nuclear generating facility in the world that is not located
adjacent to a large body of water. Instead, it uses treated sewage from several
nearby municipalities to meet its cooling water needs, recycling 20 billion US gallons
(76,000,000 m³) of wastewater each year. Like conventional power plants,
nuclear power plants generate large quantities of waste heat which is expelled
in the condenser, following the turbine.
Coloration
of plants that can take advantage of this thermal energy has been suggested by Oak Ridge National Laboratory (ORNL) as a
way to take advantage of process synergy for added energy efficiency. One example would be to
use the power plant steam to produce hydrogen from water. (Separation of water
into hydrogen and oxygen can use less energy if the water begins at a high
temperature.)
Solid waste:
The
safe storage and disposal of nuclear waste is a significant challenge and yet
unresolved problem. The most important waste stream from nuclear power plants
is spent fuel. A large nuclear reactor produces 3 cubic meters (25–30 tones) of
spent fuel each year. It is primarily composed of unconverted uranium as well
as significant quantities of transuranic actinides
(plutonium and curium,
mostly). In addition, about 3% of it is made of fission products. The actinides
(uranium, plutonium, and curium) are responsible for the bulk of the long term
radioactivity, whereas the fission products are responsible for the bulk of the
short term radioactivity.
High-level
radioactive waste:
Core
Spent
fuel is highly radioactive and needs to be handled with great care and
forethought. However, spent nuclear fuel becomes less radioactive over the
course of thousands of years of time. After about 5 percent of the rod has
reacted the rod is no longer able to be used. Today, scientists are
experimenting on how to recycle these rods to reduce waste. In the meantime, after
40 years, the radiation flux is 99.9% lower than it was the
moment the spent fuel was removed, although still dangerously radioactive. Spent fuel
rods are stored in shielded basins of water (spent fuel pools),
usually located on-site. The water provides both cooling for the still-decaying
fission products, and shielding from the continuing radioactivity. After a few
decades some on-site storage involves moving the now cooler, less radioactive
fuel to a dry-storage facility or dry cask
storage, where the fuel is stored in steel and concrete containers
until its radioactivity decreases naturally ("decays") to levels safe
enough for other processing. This interim stage spans years or decades or
millennia, depending on the type of fuel. Most U.S. waste is currently stored in
temporary storage sites requiring oversight, while suitable permanent disposal
methods are discussed. As of 2007, the United States had accumulated more
than 50,000 metric tons of spent nuclear fuel from nuclear reactors.
Underground storage at Yucca Mountain nuclear waste
repository in U.S.
has been proposed as permanent storage. After 10,000 years of radioactive
decay, according to United States Environmental
Protection Agency standards, the spent nuclear fuel will no longer
pose a threat to public health and safety. The amount of waste can be reduced
in several ways, particularly reprocessing. Even so, the remaining waste will
be substantially radioactive for at least 300 years even if the actinides are
removed and for up to thousands of years if the actinides are left in. Even
with separation of all actinides, and using fast breeder reactors to destroy by
transmutation some of the longer-lived
non-actinides as well, the waste must be segregated from the environment for
one to a few hundred years, and therefore this is properly categorized as a
long-term problem. Sub critical reactors or fusion
reactors could also reduce the time the waste has to be stored. It
has been argued that the best solution for the nuclear waste is
above ground temporary storage since technology is rapidly changing. There is
hope that current waste may well become a valuable resource in the future. According
to a 2007 story broadcast on 60 Minutes, nuclear power gives France the
cleanest air of any industrialized country, and the cheapest electricity in all
of Europe. France
reprocesses its nuclear waste to reduce its mass and make more energy. However,
the article continues, "Today we stock containers of waste because
currently scientists don't know how to reduce or eliminate the toxicity, but
maybe in 100 years perhaps scientists will... Nuclear waste is an enormously
difficult political problem which to date no country has solved. It is, in a
sense, the Achilles heel of the nuclear industry... If France is
unable to solve this issue, says Mandil, then 'I do not see how we can continue
our nuclear program.'" Further, reprocessing itself has its critics, such
as the Union of Concerned Scientists.
Low-level
radioactive waste:
The
nuclear industry also produces a huge volume of low-level radioactive waste in
the form of contaminated items like clothing, hand tools, water purifier
resins, and (upon decommissioning) the materials of which the reactor itself is
built. In the United States,
the Nuclear Regulatory Commission has
repeatedly attempted to allow low-level materials to be handled as normal
waste: land filled, recycled into consumer items, et cetera. Most low-level
waste releases very low levels of radioactivity and is only considered
radioactive waste because of its history.
Comparing
radioactive to industrial toxic waste:
In
countries with nuclear power, radioactive wastes comprise less than 1% of total
industrial toxic wastes, which remain hazardous indefinitely unless they
decompose or are treated so that they are less toxic or, ideally, completely
non-toxic. Overall, nuclear power produces far less waste material than
fossil-fuel based power plants. Coal-burning plants are particularly noted for producing large
amounts of toxic and mildly radioactive ash due to concentrating naturally
occurring metals and radioactive material from the coal. Recent reports claim
that coal power actually results in more radioactive waste being released into
the environment than nuclear power, and that the population effective
dose equivalent from radiation from coal plants is 100 times as much
as nuclear plants. However, reputable journals point out that coal ash is not
more radioactive than nuclear waste, and the differences in exposure lie in the
fact that nuclear plants use heavy shielding to protect the environment from
the heavily irradiated reactor vessel, fuel rods, and any radioactive waste on
site.
Reprocessing:
Reprocessing
can potentially recover up to 95% of the remaining uranium and plutonium in
spent nuclear fuel, putting it into new mixed oxide
fuel. This produces a reduction in long term radioactivity within
the remaining waste, since this is largely short-lived fission products, and
reduces its volume by over 90%. Reprocessing of civilian fuel from power
reactors is currently done on large scale in Britain, France and (formerly) Russia, soon
will be done in China
and perhaps India,
and is being done on an expanding scale in Japan. The full potential of
reprocessing has not been achieved because it requires breeder
reactors, which are not yet commercially available. France is generally
cited as the most successful preprocessor, but it presently only recycles 28%
(by mass) of the yearly fuel use 7% within France and another 21% in Russia. Unlike
other countries, the US
stopped civilian reprocessing from 1976 to 1981 as one part of US
non-proliferation policy, since reprocessed material such as plutonium could be
used in nuclear weapons: however, reprocessing is now allowed in the U.S. Even so,
in the U.S.
spent nuclear fuel is currently all treated as waste. In February, 2006, a new U.S.
initiative, the Global Nuclear Energy Partnership
was announced. It would be an international effort to reprocess fuel in a manner
making nuclear proliferation unfeasible, while making nuclear power available
to developing countries.
Reprocessing
Depleted
Uranium:
Uranium
enrichment produces many tons of depleted
uranium (DU) which consists of U-238 with most of the easily fissile
U-235 isotope removed. U-238 is a tough metal with several commercial uses—for
example, aircraft production, radiation shielding, and armor—as it has a higher
density than lead.
Depleted uranium is also useful in munitions as DU penetrates (bullets or APFSDS tips)
"self sharpen", due to uranium's tendency to fracture along shear
bands. There are concerns that U-238 may lead to health problems in groups
exposed to this material excessively, such as tank crews and civilians living
in areas where large quantities of DU ammunition have been used in shielding,
bombs, missile warheads, and bullets. In January 2003 the World Health Organization released a
report finding that contamination from DU munitions were localized to a few
tens of meters from the impact sites and contamination of local vegetation and
water was 'extremely low'. The report also states that approximately 70% of
ingested DU will leave the body after twenty four hours and 90% after a few days.
Debate
on nuclear power:
Proponents
of nuclear energy contend that nuclear power is a sustainable energy source that reduces carbon
emissions and increases energy security by decreasing dependence on
foreign oil. Proponents also emphasize that the risks of storing waste are
small and can be further reduced by using the latest technology in
newer reactors and that the operational safety record of nuclear plants in the
Western world is far better when compared to the other major types of power
plants. Critics believe that nuclear power is a potentially dangerous energy
source, with decreasing proportion of nuclear energy in production, and dispute
whether the risks can be reduced through new technology. Proponents advance the
notion that nuclear power produces virtually no air pollution, in contrast to
the chief viable alternative of fossil fuel combustion, and that nuclear waste
storage technology virtually eliminates the risk of radiation leakage.
Proponents also point out that nuclear power is the only viable course to
achieve energy independence for most Western countries. Critics point to the
issue of storing radioactive
waste, the history of and continuing potential for radioactive contamination by accident or
sabotage, the continuing possibility of nuclear proliferation, and the
disadvantages of centralized electricity production. Arguments
of economics and safety
are used by both sides of the debate.
Spent Fuel:
The spent fuel assemblies, on the other hand, are highly
radioactive and must initially be stored in specially designed pools resembling
large swimming pools (water cools the fuel and acts as a radiation shield) or
in specially designed dry storage containers. An increasing number of reactor
operators now store their older spent fuel in dry storage facilities using
special outdoor concrete or steel containers with air cooling.
Carbon Dioxide:
Unlike fossil fuel-fired power plants, nuclear power plants
produce no air pollution or carbon dioxide. However, a small amount of
emissions result from processing the uranium that is used in nuclear reactors.
From Fission to Electricity:
A nuclear power plant produces
electricity in almost exactly the same way that a conventional (fossil fuel)
power plant does. A conventional power plant burns fuel to create heat. The
fuel is generally coal, but oil is also sometimes used. The heat is used to
raise the temperature of water, thus causing it to boil. The high temperature
and intense pressure steam that result from the boiling of the water turns a
turbine, which then generates electricity. A nuclear power plant works the same
way, except that the heat used to boil the water is produced by a nuclear
fission reaction using 235U as fuel, not the combustion of fossil fuels. A
nuclear power plant uses much less fuel than a comparable fossil fuel plant. A
rough estimate is that it takes 17,000 kilograms of coal to produce the same
amount of electricity as 1 kilogram of nuclear uranium fuel.
Other Types of Reactors:
Although
the most common type of reactor is the Pressurized Water Reactor (PWR), many
other types of reactors are also used. In the PWR, as we described earlier,
there are two main water cycles. One is the water inside the core that is
highly radioactive. This water's heat is transferred to other, non-radioactive
water inside the second loop. This water is then used to turn a turbine. The
second most popular reactor type is the Boiling Water Reactor (BRW). This type
of reactor differs from the PWR in that there is only one water cycle.
Radioactive water is used to turn the turbine. The major disadvantage of this
is that the radioactive nuclides in the water that cause its radioactivity can
be transferred to the turbine, thus causing it to become radioactive too. This
produces more hazardous material that needs to be disposed of when a reactor is
dismantled. However, the BWR also has a few advantages. Its core can be kept at
a lower pressure, for example. Another
type of reactor is the Heavy Water Reactor (HWR). A HWR uses heavy water as a
moderator instead of normal water. Heavy water is water with deuterium, which
is an isotope of hydrogen with 1 neutron. Deuterium is heavier than normal
hydrogen, which has no neutrons. HWR's come in two types, pressurized and
boiling, just like normal "light water" reactors. The advantage of a
HWR is that un-enriched uranium fuel can be used. This is because the heavy
water is a much more efficient moderator than light water. Thus, more stray
neutrons can be slowed down enough to cause fission in 235U. This more
efficient moderator makes up for the greater abundance of the neutron-capturing
238U.
Development:
History of the use of nuclear
power and the number of active nuclear power plants Installed nuclear capacity initially rose
relatively quickly, rising from less than 1 gigawatt (GW)
in 1960 to 100 GW in the late 1970s, and 300 GW in the late 1980s. Since the
late 1980s worldwide capacity has risen much more slowly, reaching 366 GW in
2005. Between around 1970 and 1990, more than 50 GW of capacity was under
construction (peaking at over 150 GW in the late 70s and early 80s) — in 2005,
around 25 GW of new capacity was planned. More than two-thirds of all nuclear
plants ordered after January 1970 were eventually cancelled. A total of 63 nuclear units
were canceled in the USA
between 1975 and 1980.
Inside of Power Plant
Inside of Power Plant
Washington Public Power Supply
System Nuclear Power Plants 3 and 5 were never completed. During the 1970s
and 1980s rising economic costs (related to extended construction times largely
due to regulatory changes and pressure-group litigation) and falling fossil
fuel prices made nuclear power plants then under construction less attractive.
In the 1980s (U.S.)
and 1990s (Europe), flat load growth and electricity liberalization also made the
addition of large new base load capacity unattractive. The 1973
oil crisis had a significant effect on countries, such as France and Japan, which
had relied more heavily on oil for electric generation (39% and 73%
respectively) to invest in nuclear power. Today, nuclear power supplies about
80% and 30% of the electricity in those countries, respectively. A general movement against nuclear power arose during
the last third of the 20th century, based on the fear of a possible nuclear
accident as well as the history of accidents, fears of radiation as well as the history of radiation of
the public, nuclear proliferation, and on the opposition
to nuclear
waste production, transport and lack of any final storage plans. Perceived
risks on the citizens' health and safety, the 1979 accident at Three Mile Island and the 1986 Chernobyl disaster played a part in stopping new
plant construction in many countries, although the public policy organization
Brookings Institution suggests that new nuclear units have not been ordered in
the U.S. because the Institution's research concludes they cost 15–30% more
over their lifetime than conventional coal and natural gas fired plants. Unlike
the Three Mile Island accident, the much more
serious Chernobyl
accident did not increase regulations affecting Western reactors since the Chernobyl reactors were
of the problematic RBMK
design only used in the Soviet Union, for
example lacking "robust" containment buildings. Many of these reactors
are still in use today. However, changes were made in both the reactors
themselves (use of low enriched uranium) and in the control system (prevention
of disabling safety systems) to reduce the possibility of a duplicate accident.
An international organization to promote safety awareness and professional
development on operators in nuclear facilities was created: WANO; World Association of
Nuclear Operators. Opposition in Ireland, and Poland prevented
nuclear programs there, while Austria (1978), Sweden (1980) and Italy (1987) (influenced by Chernobyl) voted in referendums to
oppose or phase out nuclear power. In July 2009, the Italian Parliament passed
a law that canceled the results of an earlier referendum and allowed the
immediate start of the Italian nuclear program.
Economics:
The economics of nuclear power plants are primarily
influenced by the high initial investment necessary to construct a plant. In
2009, estimates for the cost of a new plant in the U.S. ranged from $6 to $10 billion.
It is therefore usually more economical to run them as long as possible, or
construct additional reactor blocks in existing facilities. In 2008, new
nuclear power plant construction costs were rising faster than the costs of
other types of power plants.. A prestigious panel assembled for a 2003 MIT
study of the industry found the following: In deregulated markets, nuclear
power is not now cost competitive with coal and natural gas. However, plausible
reductions by industry in capital cost, operation and maintenance costs, and
construction time could reduce the gap. Carbon emission credits, if enacted by
government, can give nuclear power a cost advantage.
Future of the industry:
Head of Reactor
As of 2007, Watts Bar 1, which came
on-line in February 7, 1996,
was the last U.S.
commercial nuclear reactor to go on-line. This is often quoted as evidence of a
successful worldwide campaign for nuclear power phase-out. However, even in the
U.S. and throughout Europe, investment in research and in the nuclear fuel cycle has continued, and some
nuclear industry experts predict electricity shortages, fossil fuel price
increases, global warming and heavy metal emissions from fossil
fuel use, new technology such as passively
safe plants, and national energy security will renew the demand for nuclear
power plants. According to the World Nuclear Association, globally
during the 1980s one new nuclear reactor started up every 17 days on
average, and by the year 2015 this rate could increase to one every
5 days. Many countries remain
active in developing nuclear power, including Pakistan, Japan, China and India, all
actively developing both fast and thermal technology, South Korea and
the United States,
developing thermal technology only, and South Africa and China,
developing versions of the Pebble Bed Modular Reactor (PBMR). Several EU
member states actively pursue nuclear programs, while some other member states
continue to have a ban for the nuclear energy use. Japan has an active nuclear
construction program with new units brought on-line in 2005. In the U.S., three
consortia responded in 2004 to the U.S. Department of Energy's
solicitation under the Nuclear Power 2010 Program and were
awarded matching funds—the Energy Policy Act of 2005 authorized loan
guarantees for up to six new reactors, and authorized the Department of Energy
to build a reactor based on the Generation IV Very-High-Temperature Reactor concept
to produce both electricity and hydrogen.
As of the early 21st century, nuclear power is of particular interest to both China and India to serve
their rapidly growing economies—both are developing fast breeder reactors. (See also energy development). In the energy policy of the United Kingdom
it is recognized that there is a likely future energy supply shortfall, which
may have to be filled by either new nuclear plant construction or maintaining
existing plants beyond their programmed lifetime. There is a possible
impediment to production of nuclear power plants as only a few companies
worldwide have the capacity to forge single-piece containment vessels, which
reduce the risk of a radiation leak. Utilities across the world are submitting
orders years in advance of any actual need for these vessels. Other
manufacturers are examining various options, including making the component
themselves, or finding ways to make a similar item using alternate methods.
Other solutions include using designs that do not require single-piece forged
pressure vessels such as Canada's
Advanced CANDU Reactors or Sodium-cooled Fast Reactors.
Inside of Head
This graph illustrates the
potential rise in CO2 emissions if base-load electricity currently
produced in the U.S. by nuclear power were replaced by coal or natural gas as
current reactors go offline after their 60 year licenses expire. Note: graph
assumes all 104 American nuclear power plants receive license extensions out to
60 years. The World Nuclear
Industry Status Report 2009 states that "even if Finland and France
each builds a reactor or two, China goes for an additional 20 plants and Japan,
Korea or Eastern Europe add a few units, the overall worldwide trend will most
likely be downwards over the next two decades". With long lead times of 10
years or more, it will be difficult to maintain or increase the number of
operating nuclear power plants over the next 20 years. The one exception to
this outcome would be if operating lifetimes could be substantially increased
beyond 40 years on average. This seems unlikely since the present average age
of the operating nuclear power plant fleet in the world is 25 years. However,
China
plans to build more than 100 plants, while in the US the licenses of almost half its
reactors have already been extended to 60 years, and plans to build more
than 30 new ones are under consideration. Further, the U.S. NRC and the U.S.
Department of Energy have initiated research into Light water reactor sustainability
which is hoped will lead to allowing extensions of reactor licenses beyond 60
years, in increments of 20 years, provided that safety can be maintained, as
the loss in non-CO2-emitting generation capacity by retiring
reactors "may serve to challenge U.S. energy security, potentially
resulting in increased greenhouse gas emissions, and contributing to an
imbalance between electric supply and demand." In 2008, the International Atomic Energy Agency
(IAEA) predicted that nuclear power capacity could double by 2030, though that
would not be enough to increase nuclear's share of electricity generation.
Nuclear
Power Plant in Bangladesh:
The
Pakistan government undertook the nuclear power project in 1961 at Rooppur in
Pabna and the land was acquired in 1963 even before France had its first
nuclear power plant in 1964.France now gets 77 per cent of its total
electricity from 55 nuclear plants, while Bangladesh’s lone project area
turned into a cattle grazing field although successive governments had no
dearth of pledges to generate more power and explore new energy resources.
The issue came up for discussion during each regime since then and soon
fizzled out, allowing the project to roll from one government to another. The
concerns that who will laugh the last matter most in leading the project to
success as development of a nuclear electricity plant takes at least seven
years — longer than the five-year tenure of an elected government, and return
to power for the second term in a row is not guaranteed as evident in
election results since 1991. Unless the head of the government
interferes properly, the project will not get momentum. There had been no
major opposition from any quarter to Bangladesh’s strides in
installing nuclear reactors for power generation. Lack of political
will and bureaucratic tangles held back the project for
decades. Bureaucrats are not directly involved in the process of
research of nuclear science. They are not well equipped with information.
Even then the scientists are to concede to their decisions. Almost every
government endorsed the experts’ suggestion that early implementation of
nuclear power project would add more value to national development as at
least 30 countries are now considering nuclear power as a viable option for
energy security. India
and Pakistan
generate 2 per cent of their electricity from nuclear reactors, while South Korea
gets 29 per cent of its electricity from nuclear plants, Japan 25, United States
20, Russia
17 and United Kingdom
14 per cent. The governments conducted
a number of feasibility studies and identified nuclear power generation
appropriate and viable for Bangladesh
both technically and economically. Meanwhile, the country obtained green
signal from the International Atomic Energy Commission, apart from assurances
of technical supports from a number of countries including France, Russia, USA, South Korea
and China
over the decades. In 1980, a 125MW plant was approved after a study that
suggested for two units of 300MW nuclear plants. Pre-implementation phase
activities for construction of the units on Rooppur site were done over the
years by the BAEC with supports from the IAEA and other national
organizations. Now the government hopes to get 1,100MW from nuclear reactors
by 2015 to meet the growing power demands, though the work is yet to get
desired pace. Bangladesh
has signed all the treaties, protocols and conventions for required for
developing nuclear energy and the IAEA has given green signal to go ahead
with the project. Bangladesh
would need further preparations for the project as it involved a lot of
matters ranging from environmental aspects to reactors safety. It may
seem difficult, but not impossible.’ Though the Rooppur site now looked
ready, but it may take seven years to implement the project once the
government signs contact with any reactor suppliers, Bangladesh
has signed agreements with a few countries for cooperation for peaceful use
of nuclear energy. Russia
is the last country with which Bangladesh signed n MoU earlier
this year. Asked whether Bangladesh
would be able to begin project work by 2010, a joint secretary at the science
and information technology ministry, who deals with the present negotiation
with Russian authorities, expressed optimism. The site safety report by
the international authorities for the proposed Rooppur plant was finalized
early this decade and some additional investigation into hydrology,
morphological analysis, subsoil investigation, seismic studies and
radiological dispersion were also carried out. The safety report was also
updated. About reactor’s safety and probability of accidents, the third
generation reactor has the highest safety mechanism with probability of one
accident in a million year. For nuclear waste disposal, Bangladesh
stands in a position for pursuing ‘take back option,’ meaning that the reactor
suppliers will take the high-level radioactive wastes back. Moreover, these
substances are now being recycled to produce metal oxide fuel, which are
considered commercial commodity nowadays. About the cost involvement in
nuclear power plant, its initial cost is higher, but experiences in other
countries say electricity production is cost effective in comparison to other
natural resources.
|
A successive government dithered
in taking a positive decision on the nuclear power plant (NPP) issue. But, it
is the credit to the successive governments that no decision had been taken
without adequate consideration. Nuclear power plant cannot a prestige issue.
The site in Rooppur in Pabna, surrounded by dense population, is not a suitable
site. Most of the world's NPPs are either in coastal areas or in remote inland
areas. Authorized discharges of radioactive liquid and gaseous wastes will
affect surrounding population and cancer incidence will go up drastically.
Another point is that under 'take back option', reactor supplier will take back
high level wastes. It must be realized that the reactor vendor has nothing to
do with radioactive wastes. It is the fuel supplier who may consider this take
back option, but then it will contrary to the international treaty. But there
is no decision about low and intermediate level wastes.
Bangladesh would need at least 500 nuclear
scientists for a 1,000 MW nuclear power plant for its operation and maintenance
after its installation. Other than scientists, the BAEC is fully ready to work
for setting up a nuclear power plant with its existing resources. It will get
4-5 years to take our own preparations following the signing of an agreement
with any state for setting up a nuclear power plant. Bangladesh and Russia have
signed in Moscow
a protocol on cooperation on peaceful use of atomic energy. The Moscow protocol was
signed in the backdrop of Bangladesh
planning to opt for a nuclear power plant to meet the crippling shortage of
electricity in the country.
Bibliography:
- An entry to nuclear power through an educational discussion of reactors
- The Nuclear Energy Option, online book by Bernard L. Cohen.
- Steve Thomas (2005), "The Economics of Nuclear Power: analysis of recent studies"PDF (305 KB), PSIRU, University of Greenwich, UK
- Nuclear power information archives from ALSOS, the National Digital Science Library at Washington & Lee University.
- Texas Will Host First New U.S. Nuclear Plants since 1970s
http://library.thinkquest.org
http://www.eia.doe.gov/kids/energyexplained/sources/non-renewable/nuclear.html
http://www.google.com/images
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