NYGH 304 Physics SIA: Nuclear Energy-

Friday, June 20, 2008

Nuclear Energy and the environment

Key Points:
· Nuclear energy is the only option available today that can provide large-scale electricity production 24/7 economically and without emitting greenhouse gases. [1]
· Nuclear energy is a vital source of electricity that can meet the nation’s growing energy needs with a secure, domestic energy supply that also protects air quality. [1]
· Nuclear power plants generate about 20% of U.S. electricity. [2]
· Nuclear power plants do not burn anything when producing electricity, so they do not produce combustion byproducts— such as nitrogen oxides, sulfur dioxide and carbon dioxide. [2]
· Cooling water discharged from a nuclear plant contains no harmful pollutants, and it meets federal Clean Water Act requirements and state standards for temperature and mineral content. [2]
· Environmental responsibility is an important part of nuclear power plant management. Plants are designed, built and regulated to prevent radioactive emissions. The companies that operate nuclear power plants also voluntarily work to protect nearby wildlife and their habitats. For example, some companies have developed environmentally rich wetlands, providing better nesting areas for waterfowl and other birds; new habitats for fish; and sanctuaries for other wildlife, flowers and grasses. “Residents” at power reactor sites include many endangered and protected species, such as bald eagles, manatees, crocodiles, blue crabs, oysters and fish. Several species of endangered plant life also find refuge at nuclear plant sites. [2]
· Strict standards, careful control—All methods of producing electricity affect the environment to some degree, but the impacts from nuclear energy are minimal—one of the lowest on a per-kilowatt-hour basis. [3]
· Because the fuel in nuclear power plants is radioactive, nuclear plants are carefully designed, built and monitored to prevent releases of radioactive material. The Environmental Protection Agency sets—and the NRC enforces—strict standards governing radiation emissions. To make sure that nuclear power plants operate well within those standards, radiation levels at every plant are monitored 24 hours a day, seven days a week. Even soil, cows' milk from neighboring farms, and fish and sediment in nearby rivers and lakes are monitored periodically. The monitoring instruments are so sensitive that they can measure even trace amounts of radiation. Nuclear power plant emissions are always well below the safe levels permitted by federal standards. That is why the environment has never been harmed by radiation emissions from a U.S. nuclear power plant. [3]
· By substituting for other fuels in electricity production, nuclear energy has significantly reduced U.S. emissions of nitrogen oxides, sulfur dioxide and carbon dioxide. [2]

Cutting down on carbon dioxide emission:
· Carbon dioxide—the greenhouse gas mainly emitted by human activity—is the major focus of global discussions to reduce emissions. Many scientists believe that carbon dioxide emissions increase Earth’s warming effect, bringing about changes in climate. [2]
· Because nuclear power plants do not burn fuel, they do not emit combustion by-products. By substituting for other fuels in electricity production, nuclear energy has significantly reduced U.S. and global emissions of carbon dioxide (CO2), the chief greenhouse gas. [3]
· By using nuclear energy rather than fossil fuel-based plants, electric utilities prevented 681 million metric tons of carbon dioxide emissions in 2006. [1]
· Worldwide, nuclear energy prevents the emission of more than 2.6 billion metric tons of carbon dioxide each year. [1]
· In the European Union, a recent study of the region’s carbon avoidance shows that an additional 704 million metric tons of carbon dioxide would be emitted if all nuclear power plants in these countries were removed from the electricity grid.
· Worldwide, nuclear energy has significantly reduced greenhouse gas emissions. Approximately 430 nuclear power plants in 31 nations produce 17 percent of the world's electricity-while reducing CO2 emissions by some 500 million metric tons of carbon. [3]
· Also in 2006, U.S. nuclear plants prevented the discharge of 681 million metric tons of carbon dioxide into the atmosphere. This is nearly as much carbon dioxide as is released from all U.S. passenger cars. [2]
· Between 1973 and 1999, the nation's nuclear plants reduced the cumulative amount of carbon emissions by 2.61 billion tons of carbon. [3]

Comparing Electricity-Sector Carbon Dioxide Emissions
Generating 1 million kilowatt-hours of electricity produces:
􀂃 996 metric tons of carbon dioxide from a coal-fired plant
􀂃 809 metric tons of carbon dioxide from an oil-fired plant
􀂃 476 metric tons of carbon dioxide from a natural gas-fired plant
􀂃 None from a nuclear power plant.
Conclusion: Nuclear energy, like all non-emitting technologies such as wind turbines and hydroelectric generation, does not emit criteria pollutants or greenhouse gases in the direct production of electricity.

Cutting down on nitrogen oxide (NOx):
· Nitrogen oxides play a major role in the formation of ozone, which is detrimental to human health. Nitrogen oxides also are a significant contributor to acid rain. [2]
· By substituting for fossil fuels in electricity generation, U.S. nuclear power plants currently avoid almost two million tons of NOx emissions annually. [3]
· In 2006, U.S. nuclear power plants avoided the emission of 1 million short tons of nitrogen oxides—the same amount emitted by more than 51 million passenger cars in a year. [2]
· Between 1973 and 1999, U.S. nuclear power plants reduced cumulative emissions of nitrogen oxide 31.6 million tons and 61.7 million tons.

Cutting down on sulfur dioxide (SO2):
· Sulfur dioxide contributes to acid rain. A main objective of the Clean Air Act amendments is to reduce the amount of sulfur dioxide emitted into the atmosphere. [2]
· In 2006, nuclear plants avoided the emission of 3.1 million short tons of this pollutant—more than twice that avoided by hydro electric power and all other renewable energy sources combined. [2]
· By displacing fossil fuels to generate electricity, this increased generation avoided 480,000 tons of (SO2) emissions, or about 37 percent of the required Phase I reduction. [3]
· In 2006, U.S. nuclear power plants reduced emissions of sulfur dioxide by 3.1 million short tons.
· Between 1973 and 1999, U.S. nuclear power plants reduced cumulative emissions of sulfur dioxide by 61.7 million tons.

Some Quotes On Nuclear Energy’s Environmental Benefits [1]

“[The United States should] provide opportunities for nuclear power to play a continuing role in a future low-carbon electricity sector. …Because nuclear power is one of the few options for no-carbon electricity production, efforts should be made to preserve this option.”
—Pew Center on Global Climate Change

Recommendation in “Agenda for Climate Action”
“A more diverse mix of voices are taking a positive second look at nuclear energy—environmentalists, scientists, the media, prominent Republicans and Democrats, and progressive think tanks. They are all coming to a similar conclusion: If we are to meet the growing electricity needs in this country and also address global climate change, nuclear energy has a crucial role to play.”
—Patrick Moore
Co-founder, Greenpeace
Co-chair, Clean and Safe Energy Coalition

“Even some environmental groups have come to realize that a new generation of safer nuclear plants is the best option for addressing the nation’s mounting energy needs. ...Nuclear units emit no greenhouse gases from plant operations, which make nuclear a compellingly green alternative to coal, oil and natural gas.”
—USA Today
Editorial
May 16, 2007

Citations:
[1]: Nuclear Energy Institute (2008) Nuclear Energy Plays Essential Role in Reducing Greenhouse Gas Emissions. [On Line] Available from: http://www.nei.org/filefolder/Nuclear_Energy_Plays_Essential_Role_in_Reducing_Greenhouse_Gas_Emissions_0408.pdf (15 June 2008)

[2]: Nuclear Energy Institute (2007) Nuclear energy and the environment. [On Line] Available from: http://www.nei.org/filefolder/nuclear_energy_and_the_environment_1007.pdf (15 June 1008)

[3]: Nuclear Management Company (2007) Nuclear Facts. [On-Line] Available from: http://www.nmcco.com/education/facts/environment/energy.htm (June 15, 2008)

The Nuclear Fuel Cycle (Perhaps for the ppt?)

The nuclear fuel cycle is the series of industrial processes which involve the production of electricity from uranium in nuclear power reactors.
Uranium is a relatively common element that is found throughout the world. It is mined in a number of countries and must be processed before it can be used as fuel for a nuclear reactor.
Electricity is created by using the heat generated in a nuclear reactor to produce steam and drive a turbine connected to a generator. Fuel removed from a reactor, after it has reached the end of its useful life, can be reprocessed to produce new fuel.

From:
World Nuclear Association (2005) The Nuclear Fuel Cycle. [On Line] Available from: http://www.world-nuclear.org/info/inf03.html (June 15, 2008)

-Ai Leng- (This is my part on the link between nuclear power plants and the environment, which is also linked to the advantages. )

the beauty exposed ;

Here are some videos explaining the principle behind nuclear energy: nuclear physics!
http://www.animate4.com/nuclear/nuclear-energy-nuclear-fusion-nuclear-physics/nuclear-energy-nuclear-fusion.mpg
http://www.animate4.com/nuclear/nuclear-energy-nuclear-fusion-nuclear-physics/nuclear-energy-nuclear-fusion-renewable-energy.mpg
http://www.animate4.com/nuclear/nuclear-energy-nuclear-fusion-nuclear-physics/energy-nuclear-energy-nuclear-fusion-renewable-energy-1.mpg
http://www.animate4.com/nuclear/nuclear-energy-nuclear-fusion-nuclear-physics/energy-nuclear-energy-nuclear-fusion-renewable-energy.mpg

Summary:
A nuclear reaction involves the collision of two nuclei or nuclear particles. Binding energy is released in the course of the reaction. The energy released in a nuclear reaction may be either kinetic energy, emission of high energy protons called gamma rays. Some energy can remain in the nucleus as metastable energy. Energy may also be given off in the form of X-rays.

SIMIN WAS HERE

the beauty exposed ;

Nuclear energy produces 16 percent of the world’s electricity, compared with coal, which produces 39 percent and hydropower, which produces 19 percent. Just how green is nuclear energy?
NOT
1.Every step (except reactor operation) in the long chain of processes that makes up the nuclear fuel “cycle” - mining, milling fuel fabrication, uranium enrichment, construction and decommissioning of the reactor, and waste management - burns fossil fuels and hence emits carbon dioxide (CO2)
2.CO2 emissions from the nuclear fuel cycle are only small when high-grade uranium ore is used
3.However, there are very limited reserves of high-grade uranium in the world and most are in Australia and Canada
4.Worldwide electricity demand is predicted to grow by 85 percent by 2030, nuclear power would have to almost double its capacity just to maintain its current share of the energy mix, therefore it is not a feasible solution for an energy source
5.Nuclear power produces toxic, radioactive waste, for which no safe method of disposal has been approved. U.S. nuclear plants have produced over 40,000 metric tons of high-level radioactive waste, which is deadly for hundreds of thousands of years. It is produced at an annual rate of about 10,000 tonnes in nuclear power reactors worldwide.
6.In addition to the perennial problems of plant malfunction and human error, terrorism looms large as a threat to nuclear plants and everyone working and living in their vicinity. The 1986 Chernobyl disaster is an example of a disastrous catastrophe that killed many.
7. The cost of building nuclear plants is too expensive. The world's 440 operating power reactors, with about 364,000 MWe of total capacity, produce about 16% of the world's electricity. Coal, gas and oil account for four times that amount — about 64%. So to replace fossil fuel generated electricity with nuclear power would require a five-fold increase in the number of reactors, from 440 to about 2200. The cost of the additional 1760 reactors would be several trillion dollars.

BUT!
THERE'S AN ALTERNATIVE!
"Physicists and engineers at Beijing's Tsinghua University have made the first great leap forward in a quarter century, building a new nuclear power facility: a pebble-bed reactor (PBR) – sometimes also known as a Pebble Bed Modular Reactor (PBMR). This reactor is small enough to be assembled from mass-produced parts and cheap enough for emerging economies. Its safety is a matter of physics, not operator skill or reinforced concrete. This reactor is meltdown-proof.

What makes it so safe is the fuel: instead of conventional fuel rods made of enriched uranium, PBRs use small, pyrolytic graphite coated pebbles with uranium cores. As a PBR reactor gets hotter, the rapid motion of atoms in the fuel decreases probability of neutron capture by U-235 atoms. This effect is known as Doppler Broadening. Nuclei of heated uranium move more rapidly in random directions generating a wider range of neutron speeds. U-238, the isotope which makes up most of the uranium in the reactor, is much more likely to absorb the faster moving neutrons. This reduces the number of neutrons available to spark U-235 fission. This, in turn, lowers heat output. This built-in negative feedback places a temperature limit on the fuel without operator intervention.

PBRs use high-pressure helium gas, not water, for cooling. Reactors have been “run dry” – without cooling gas. Result: they simply stabilize at a given temperature – lower than the pebbles’ shell melting point. No meltdown can occur.

Safe Nuclear Power and Green Hydrogen Fuel, Pic 2

PBR from www.pbmr.co.za

South Africa may have the most modern PBR on the drawing board. With the help of German scientists – acknowledged leaders in the field - they have planned to build several reactors within the next five years. Images in this article come from their design.

The reactor core is a bin of uranium fuel pebbles. Each tennis ball-sized pebble is rotated and/or checked for reactivity by removing them from the bottom of the funnel shaped reactor core. Spent pebbles are replaced by adding new ones at the top of the stack. Used ones that are still reactive also go to the top of the bin. The reactor can be re-fueled without stopping power production – not possible in conventional rod reactors which requires a full shut down.

Pebbles, because of their round nature, allow the cooling gas to be introduced at the bottom and pass freely through the stack. The heated gas is removed to perform work like spinning a turbine to generate electricity then recycled in a closed loop back to the reactor core.

PBRs use helium, which has high thermal conductivity and inertness (read: fireproof and noncorrosive) for cooling. This makes them more efficient at capturing heat energy from nuclear reactions than standard reactor designs. The ratio of electrical output to thermal output is about 50%.

Safe Nuclear Power and Green Hydrogen Fuel, Pic 3

Reactor Interior – pebbles in red: www.eskom.co.za/ nuclear_energy/ pebble_bed/ pebble_bed.html

The high-temperature gas design also has a silver lining – it can produce hydrogen. Think about that – fuel cell vehicles need expensive-to-produce hydrogen to run on – this reactor could make hydrogen as a byproduct.

Generation of hydrogen has been the biggest stumbling block to it adoption as a clean fuel. Hydrogen, found primarily in water, is expensive to extract as a gas. While the technical problems of handling, storage and use as fuel are largely solved, the high energy cost to produce hydrogen has made it an energy transport medium, not a source.

These new reactors run at high temperatures which are perfect for cracking abundant water or helium gas into hydrogen which can then be used as a green fuel – burning hydrogen just produces water vapor.

PBRs could produce cheap hydrogen that could be piped to areas of need or used in the local communities.

Plant sites are much smaller than traditional nuclear power plants. Their modular design allows for smaller plants that can grow with needs. A single PBR reactor would consist of one main building covering an area of about 1,300 square meters – less than half a football field. It would be about 42m high (6 stories), some of it below ground level. Billion dollar steel reinforced concrete containment vessels are not required – any coolant leak would be in the form of nonradioactive helium gas which would quickly disperse with out causing any ill effects.

Safe Nuclear Power and Green Hydrogen Fuel, Pic 4

Internal functioning with cooling diagram: www.eskom.co.za/nuclear_energy/pebble_bed/pebble_bed.html

Safe Nuclear Power and Green Hydrogen Fuel, Pic 5

Fuel Spheres: www.eskom.co.za/nuclear_energy/pebble_bed/pebble_bed.html

Each PBR would produce between 100 and 200 MW – small, in comparison to light and heavy water reactors which typically product around 1,000 MW. But they could easily be scaled up by adding reactors.

Ten PBR reactors producing 1,100 MW would occupy an area of no more than three football fields. Each PBR could serve about 30,000 to 40,000 homes.

Control rooms - much simpler than standard ones - would have a few PCs and extra monitors instead of banks of valves and dials. Each control room could monitor and manage up to 10 reactors.

One of the key features to this technology, especially important in China where energy demand is exploding, is its modular nature. While conventional reactors in operation today are all one of a kind – although many are based on the same designs – PBR reactors could de built with standard rail-movable components. When a new power plant is needed, they simply load the parts on a train with a construction crew and can have it delivering power in short order. Traditional plants in the US were sunk principally by long construction times and cost overruns, not environmental regulations.

Nuclear waste disposal has become a hot-button issue. Standard nuclear waste is very radioactive for 10,000 years or more. It must be transported to and stored in special containment facilities – normally underground. It can also be reprocessed but this is costly and technically difficult. There are only 3 reprocessing facilities worldwide: Thorpe in England, Cogema in France and Myakrt1 Chemical Combine in Russia. Far away from most of the world that needs clean, inexpensive power.

Fuel pebbles have 4 caps of containment built in. Many authorities consider pebbled radioactive waste stable enough it can be safely disposed of in geological storage – without any additional shielding or protection. Even in tests where pebbles were exposed to very high heat without coolant for long periods, they showed no outward damage. If one did manage to break a pebble it would only release one tiny (0.05mm) uranium dioxide particle. This particle is too heavy to be wind borne and so could not be blown into other areas like the fallout from the explosion at Chernobyl.

PBR proponents state they plan to store all waste products on the plant site – avoiding costly and dangerous radioactive material movement. "

1.According to the Keystone Center’s “Nuclear Power Joint Fact Finding” released last year, failing to replace existing nuclear power plants over the next half-century would actually increase carbon emissions by 12.5 gigatons.
2.The World Health Organization (WHO) carried out several studies after the 1986 Chernobyl disaster; one, conducted 19 years later, concluded that 75 deaths could be directly attributed to the accident. Other WHO findings: 28 deaths among first-responders in the year after the accident could be directly linked to acute radiation sickness; there was a large increase in highly treatable tyroid cancerns among young people and no clearly demonstrated increases in leukemia or other non-thyroid solid cancers; and the lifetime risk of cancer deaths among those exposed to Chernobyl radiation was about 3 to 4 percent higher than average
3. By comparison, the health impacts of the 1979 Three Mile Island accident in the U.S. were minuscule, with no attributable illnesses or deaths. The Keystone Center’s “Nuclear Power Joint Fact Finding” last year said the average dose of radiation to the region’s 2 million people was about 1 millirem, with the maximum exposure to individuals right outside the site at less than 100 millirem. By comparison, a full set of chest x-rays delivers 6 millirem of radiation, and a year’s exposure to natural background radiation gets you 100 to 125 millirem.
4. Participants in the Keystone Center “Nuclear Power Joint Fact Finding” all conceded that “on balance, commercial nuclear power plants in the U.S. are safer today than they were before the 1979 accident at Three Mile Island.” In fact, an industry study in 2003 found that even a direct-side impact by a large commercial airliner wouldn’t cause a loss of coolant at a nuclear power plant.
5. A National Academy of Sciences study found a low risk of widespread harm from either a terrorist attack or a serious accident involving spent nuclear fuel. And the Keystone Center’s “Nuclear Power Joint Fact Finding” found that “the risk of a major accident at a nuclear facility is not seen as a significant risk by investors today.”
6. A 2001 study by the Paul Scherrer Institute in Switzerland (quoted in “The Revenge of Gaia”) found that, beteween 1970 and 1992, nuclear power had the best safety record of all major energy sources, both in terms of total deaths and deaths per terawatt of energy produced each year. The results for the top four sources were coal: 6,400 total deaths, 342 deaths per terawatt per year; hydro power: 4,000 total deaths, 884 deaths per terawatt per year; natural gas: 1,200 total deaths, 85 deaths per terawatt per year; nuclear power: 31 total deaths, 8 deaths per terawatt per year.
7. A life-cycle assessment by Meier Engineering Research found that nuclear fission energy actually had a lower life-cycle greenhouse gas emission rate than solar (using an eight-kilowatt, building-integrated photovoltaic system for the assessment): 15 tons of carbon dioxide-equivalent per gigawatt-electric of electricity, compared to 39 tons for photovoltaic. Of course, those rates were considerably higher for fossil-fuel sources like natural gas (469 tons) or coal (974 tons).
8. Nuclear power makes economic sense. According to the Energy Information Administration, operation, maintenance and fuel costs per kilowatt-hour for nuclear plants are more than twice those for hydroelectric, but nearly a third less than those for fossil steam energy and two-thirds less than either gas turbine energy or small-scale photovoltaic or wind energy.
9. During the nuclear testing heyday of the Cold War era, the superpowers set off numerous nuclear weapons; in 1962 alone, test bombs equaled the output of 20,000 Hiroshima warheads. Such tests, Lovelock argues, released radioactive materials into the air equal to two Chernobyls a week for a whole year … yet no proven health damage to humans was observed in subsequent years. (For more details, see “The Revenge of Gaia,” pages 94 - 95).

CONCLUSION
Though there are indeed many disadvantages to nuclear power, however, as compared to the alternative energy sources like solar energy or fossil fuels, it seems that nuclear power is the best choice out of the rest. Therefore I conclude that with current technologies, the green energy for the future can only be nuclear energy, unless a technological breakthrough occurs.

REFERENCE
Clayton, Mark. (2007). How Green is Nuclear Power?. Retrieved June 1, 2008 from http://www.csmonitor.com/2007/0307/p01s04-sten.html?page=1

Dunn, Philip. (2005). Safe Nuclear Power and Green Hydrogen Fuel. Retrieved June 3, 2008 from http://www.physorg.com/news8956.html

Jim, Green. (2005). Global warming: Nuclear power no solution. Retrieved May 31, 2008 from http://www.greenleft.org.au/2005/622/34954

Rainwater van Suntum, Lisa. (2005).Spinning Nuclear Power into Green.Retrieved June 1, 2008 from http://www.prwatch.org/prwissues/2005Q1/nuke2.html

Gregory, Shirley Siluk. (2008) . Devil's Advocate: 10 Green Arguments for Nuclear Power. Retrieved June 5, 2008 from http://planetsave.com/blog/2008/01/15/devils-advocate-10-green-arguments-for-nuclear-power/

Simin Was Here

the beauty exposed ;

Principles of Nuclear Energy

Radiation

During the splitting of any other fission nucleus, radiation is produced. Any material producing radiation is called radioactive. There are four distinct types of radiation associated with nuclear fission, called alpha, beta, gamma and neutron radiation:

Alpha radiation

- Alpha radiation is a form of nuclear fission where the parent atom splits into two daughter products. It is a type of radioactive decay in which an atomic nucleus emits an alpha particle (two protons and two neutrons bound together into a particle identical to a helium nucleus) and transforms into an atom with a mass number 4 less and atomic number 2 less.^[1] Alpha radiation is fundamentally a quantum tunneling process. Unlike Beta radiation, alpha radiation is governed by the strong nuclear force.

Beta Radiation

- Beta radiation is a type of radioactive decay in which a beta particle (an electron or a positron) is emitted. In the case of electron emission, it is referred to as "beta minus" (β⁻), while in the case of a positron emission as "beta plus" (β⁺). Kinetic energy of beta particles has continuous spectrum ranging from 0 to maximal available energy (Q), which depends on parent and daughter nuclear states participating in the decay. Typical Q is of order of 1 MeV(amount of energy equivalent to that gained by a single unbound electron when it is accelerated through an electrostatic potential difference of one volt, in a vacuum)^[2], but it can be from few keV to few tens MeV. The most energetic beta particles are ultrarelativistic, with speeds very close to the speed of light.

Gamma radiation

- Gamma rays are the most dangerous form of radiation emitted by a nuclear explosion because of the difficulty in shielding them. This is because gamma rays have the shortest wavelength of all waves in the electromagnetic spectrum, and therefore have the most ability to penetrate through any gap, even a subatomic one, in a what might otherwise be a shield.^[3]

- Gamma-rays are not stopped by the skin. They can induce DNA alteration by interfering with the genetic material of the cell. DNA double-strand breaks are generally accepted to be the most biologically significant lesion by which ionizing radiation causes cancer and hereditary disease^.A study done on Russian nuclear workers exposed to external whole-body gamma radiation at high cumulative doses shows the link between radiation exposure and death from leukemia, lung, liver, skeletal and other solid cancers^.Alongside radiation, gamma-rays also produce thermal burn.

Neutron Radiation

- The neutrons in reactors are generally categorized as slow (thermal) neutrons or fast neutrons depending on their energy. Thermal neutrons are similar to a gas in thermodynamic equilibrium but are easily captured by atomic nuclei and are the primary means by which elements undergo atomic transmutation.

In order to achieve an effective fission chain reaction, the neutrons produced during fission must be captured by fissionable nuclei, which then split, releasing more neutrons. In most fission reactor designs, the nuclear fuel is not sufficiently refined to be able to absorb enough fast neutrons to carry on the fission chain reaction, due to the lower cross section for higher-energy neutrons, so a neutron moderator must be introduced to slow the fast neutrons down to thermal velocities to permit sufficient absorption.^[5]Common neutron moderators include graphite, light water and heavy water. A few reactors (fast neutron reactors) and all nuclear weapons rely on fast neutrons. This requires certain changes in the design and in the required nuclear fuel. The element beryllium is particularly useful due to its ability to act as a neutron reflector or lens. This allows smaller quantities of fissile material to be used and is a primary technical development that led to the creation of neutron bombs.

Principles of Thermodynamics

In thermal physics, thermal energy is the energy portion of a system that increases with its temperature. In thermodynamics, thermal energy is the internal energy present in a system in a state of thermodynamic equilibrium by virtue of its temperature. "thermal energy" can only be defined as any spontaneous flow of energy from one object to another, caused by a difference in temperature between two objects; thus, an object cannot possess "heat".This is explained by the second law of thermodynamics.

Internal energy is the sum of all microscopic forms of energy of a system. It may be viewed as the sum of kinetic and potential energies of the molecules; it consists of the following types of energies e.g. Nuclear energy, Sensible energy, Latent energy and chemical energy etc.

Nuclear energy is the tremendous amount of energy associated with the strong bonds within the nucleus atom itself. It is energy due to the splitting (fission) or merging together (fusion) of the nuclei of atoms.

Zeroth Law of Thermodynamics

- The Zeroth Law of Thermodynamics introduces the concept of thermodynamic equilibrium, in which two objects have the same temperature.

- If we bring two objects that are initially at different temperatures into physical contact, they eventually achieve thermal equilibrium.

- During the process of reaching thermal equilibrium, heat is transferred between the objects.

- The amount of heat transferred Q is proportional to the temperature difference T between the objects and the heat capacity c of the object. Therefore, the formula of the Zeroth Law is (Q = c delta T). ^[8]

- The heat capacity is the constant that tells how much heat is added per unit temperature rise.

- Therefore in the Zeroth Law, in the process of reaching thermodynamic equilibrium, heat is transferred from the warmer object to the cooler object. At thermodynamic equilibrium, heat transfer is zero.

First Law of Thermodynamics

- The First law is also known as the law of Conservation of Matter.

- The amount of work depends not only on the initial and final states of the gas but also on the process which produces the final state. The amount of heat transferred into or from a gas also depends on the initial and final states and the process which produces the final state.

- The difference of the heat flow into the gas and the work done by the gas depends only on the initial and final states of the gas and does not depend in the process which produces the final state.

- Therefore, the internal energy of the gas only depends on the state of gas and not on any process. The internal energy is a state variable, just like the temperature.^[9]

- The First Law of Thermodynamics defines the internal energy as equal to the difference of the heat transfer into a system and the work done by the system.

- Any thermodynamic system in an equilibrium state possesses a state variable called the internal energy. Between any two equilibrium states, the change in internal energy is equal to the difference of the heat transfer into the system and work done by the system.

- Let E1 be the internal heat of the 1st object and E2 be the internal heat of the 2^nd object. Q is the heat transfer between 2 objects and W is the work done of the 2 objects.^[10]

- Therefore, the formula of the First Law of thermodynamics is E2 - E1 = Q – W.

Second Law of thermodynamics

- "Entropy" is defined as a measure of unusable energy within a closed or isolated system. As usable energy decreases and unusable energy increases, "entropy" increases. Entropy is also a gauge of randomness or chaos within a closed system. ^[6]As usable energy is lost, disorganization, randomness and chaos increase.

- The balance equation of the second law, expressed as S > 0, says that in all natural processes the entropy of the world always increases, and thus whereas with the first law there is no time, and the past, present, and future are indistinguishable, the second law, with its one-way flow, introduces the basis for telling the difference. ^[7]

- The Second Law of Thermodynamics states that "in all energy exchanges, if no energy enters or leaves the system, the potential energy of the state will always be less than that of the initial state."

- For example: A car that has run out of gas will not run again until you walk 10 miles to a gas station and refuel the car. Once the potential energy locked in carbohydrates is converted into kinetic energy, the organism will get no more until energy is input again. In the process of energy transfer, some energy will dissipate as heat. Entropy is a measure of disorder: cells are not disordered and so have low entropy. The flow of energy maintains order and life.

Third Law of Thermodynamic
- The Third Law of Thermodynamics says: "The entropy of a pure perfect crystal is zero (0) at zero Kelvin (0° K)."

- As the temperature of a system approaches absolute zero, its entropy approaches a constant (for pure perfect crystals, this constant is zero). A pure perfect crystal is one in which every molecule is identical, and the molecular alignment is perfectly even throughout the substance. For non-pure crystals, or those with less-than perfect alignment, there will be some energy associated with the imperfections, so the entropy cannot become zero.^[11]

- In other words, a body at absolute zero could exist in only one possible state, which would possess a definite energy, called the zero-point energy. This state is defined as having zero entropy

Citings:
(1) Free energy generators and the 2nd law of thermodynamics; Dr. Veniamin Filimonov http://www.cold-nuclear-fusion.com/articles/
free-enegry-generator.html
Date accessed:12/6/08

(2) How Nuclear Radiation Works © 1998-2008 HowStuffWorks, Inc. http://science.howstuffworks.com/nuclear2.htm
Date accessed: 12/6/08

(3) Gamma Radiation; Idaho State University; Last updated: 1/31/2008 http://physics.isu.edu/radinf/gamma.htm
Date accessed: 12/6/08

(4) Beta Particles; U.S Environmental Protection Agency Last updated: Friday, November 16^th 2007
http://www.epa.gov/radiation/understand/
beta.html
Date accessed:12/6/08

(5) Nuclear Power Fundamentals http://www.tpub.com/content/doe/h1019v1/
css/h1019v1_89.htm
Date accessed: 12/6/08

(6) Frank L. Lambert, Professor Emeritus (2008) Entropy and the Second Law of Thermodynamics [on-line]
www.2ndlaw.com/ (05-06-08)

(7) AllAboutScience.org (--) Second Law of Thermodynamics [on-line]
www.allaboutscience.org/second-law-of-thermodynamics.htm (05-06-08)

(8) M.J. Farabee (2001) LAWS OF THERMODYNAMICS [on-line]
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookEner1.html (05-06-08)

(9) Pidwirny, M. (2006). "Laws of Thermodynamics". Fundamentals of Physical Geography, 2nd Edition [on-line]
www.physicalgeography.net/fundamentals/6e.html (05-06-08)

(10)National Aeronautics and Space Administration, Tom Benson, (2006) First Law of Thermodynamics [on-line]
www.grc.nasa.gov/WWW/K-12/airplane/thermo1.html (05-06-08)

(11)Splung.com (2007) The Third Law of Thermodynamics [on-line]
http://www.splung.com/content/sid/6/page/thirdlaw (05-06-08)

Emily Chua (8)

the beauty exposed ;

Monday, June 16, 2008

Here are some charts that will be pasted on our poster:
The conclsion is a bit weird. I will TRY to modified it.

Some of the charts I am unable to post up to blogger as they are in the pdf file,

but thery will be printed and pasted on the poster. ^^

[1]: This Chart shows that nuclear energy had been increasingly taking a great part in the total electricity production from 1970s until the 21st century.

[1]: Sixteen 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, Slovakia, South Korea, Sweden, Switzerland, Slovenia and Ukraine get one third or more. Japan, Germany and Finland get more than a quarter of their power from nuclear energy, while the USA gets almost one fifth.

[1]: This chart shows that nuclear electricity is taking a great part out of total electricity.

[2]: this chart shows that nuclear energy emits the least amount of carbon dioxide compared to the rest of the energies.

Bibliography:

[1]: World Nuclear Association (2007) Nuclear Power in the World Today. [On Line] Available from: http://www.world-nuclear.org/info/inf01.html (June 15, 2008)

[2]: World Nuclear Association (2008) Energy Balances and CO2 Implications. [On Line] Available from: http://www.world-nuclear.org/info/inf100.html (June 15, 2008)

Ai Leng (21)

the beauty exposed ;

Thursday, June 12, 2008

Here's a video link we have found from the following website:

Nuclear Energy Institution (--) Nuclear Energy Institute - Proven. Prepared. Protected. Security at America’s Nuclear Power Plants [on-line] http://www.nei.org/resourcesandstats/documentlibrary
/safetyandsecurity/video/nuclearpowerplantsecurityvideo/

and this is the video link:

Proven. Prepared. Protected. Security at America's Nuclear Power Plants
http://video.google.com/videoplay?docid=-2984995
674597546526

(Streaming audio-video clip presenting the security measures in effect at nuclear power plants, with company security directors and plant security officers sharing their expertise. For more information on Nuclear, Clean Air Energy: http://www.nei.org/)

Here are some of the information we have gotten after viewing the video: (Some information are directly lifted from the video to ensure that we do not get the information wrong)

Nuclear energy is the largest source of electricity in America and they emit no greenhouse gases.
The nuclear reactors in America provide power 24/7.
Highly trained professionals are employed to operate the facilities
" ..Safety and Security have always been the industry's top priority..."
There are multiple layers of steel and concrete surrounding the core of the reactors for better protection
Controller simulators there help to train operators who can respond to abnormal events to keep the plant safe
Nuclear power plants do have several back-up system and a highly trained well-armed paramilitary security force to protect the plants from any external threats. e.g. terrorists attacks
The power plants' security are subjected to stringent standards set by the US Nuclear Regulatory Commission
About 7000 trained security professionals guard the nuclear power plant sites in the US
Among all, almost two-thirds of them have previous military, law-enforcement or security experience.
Since 11th of September 2001, nuclear plants have undertaken a broad range of improvements to make security capabilities even stronger
There are layers of security to best protect the nuclear power plants. In the protected area, the second layer, access here is strictly controlled. The third layer, surrounding the vital area of the power plant, is heavily guarded and has tight security

Indeed, it does take a lot of effort and capital to construct and maintain the power plant well, keeping it safely and carefully protected from any terrorists attacks and others.

Kaiqing (7) Elvendork!!! and Emily (8)

the beauty exposed ;

According to Nuclear Energy Institution, to date of 2007, nuclear energy provides almost up to 20 percent of

United States of America

's electricity and is its top source of emission-free electricity. In the

United States

, there are 104 operating reactors, consisting of 35 boiling water reactors and 69 pressurized water reactors. [1]

Pressurized Water Reactors

Source: ICJT (--) ICJT.org - Nuclear Power Plants in the World [2]

Boiling Water Reactors

Source: ICJT (--) ICJT.org - Nuclear Power Plants in the World [2]

There are a total of 32 companies licensed to operate the nuclear reactors in the US. Out of the 50 states in US, 31 of them are with operating reactors, which include Alabama, Florida, Georgia, Kansas, Maryland, New York, Ohio, Texas, Virginia, Washington and many other states [3]. Among the 31 states, nuclear makes up the largest percentage of their electricity generated as of the table below:

State	Percent
Vermont	73.7
South Carolina	51.2
New Jersey	50.7
Connecticut	48.9
Illinois	47.8
New Hampshire	46.0

Source: Nuclear Energy Institute (--) Nuclear Energy Institute - U.S. Nuclear Power Plants [1]

This is the U.S. Nuclear Generating Statistic from 2004 to 2007

Year	Total Electricity Generation (MWh)	Nuclear Generation (MWh)	Nuclear Fuel Share (Percent)	Capacity Factor (Percent)		Summer Capacity (MW)
2004	3,970,555,289	788,528,387	19.9		90.1	99,628
2005	4,055,422,744	781,986,365	19.3		89.3	99,988
2006	4,064,702,228	787,218,636	19.4		89.6	100,334
2007*	4,159,513,913	806,486,978	19.4		91.8	100,334

Source: Global Energy Decisions/Energy Information Administration
Updated on 4/08

Here are some other figures of the number of operating nuclear power plants in the world [4]

Top 5 States - Operating Nuclear Power Plants [4]

United States - 104 operating nuclear power plants
France - 59 operating nuclear power plants.
Japan - 54 operating nuclear power plants.
Russia - 30 operating nuclear power plants.
United Kingdom - 27 operating nuclear power plants.

Top 5 States - % of Electricity from Nuclear Power Plants [4]

Lithuania - 80% of its electricity from nuclear power
France - 78% of its electricity from nuclear power.
Slovakia - 57% of its electricity from nuclear power.
Belgium - 55% of its electricity from nuclear power.
Sweden - 50% of its electricity from nuclear power.

However, these figures are up to date of 2005. As of a World Nuclear Industry Status Report 2007 to date of 1^st November 2007 [5], there are currently 439 operating nuclear reactors in the world.

As of the total number of nuclear reactors in the world, they provided around 15 percent of the world's electricity production in 2007. [6] Overall, 16 countries relied on nuclear energy to generate at least one-quarter of their total electricity supply. Below is the table of countries generating the largest percentage of their electricity in 2007 from nuclear energy.

Country	Percent
France	76.8
Lithuania	64.4
Slovakia	54.3
Belgium	54.0
Ukraine	48.1
Sweden	46.1
Armenia	43.5
Slovenia	41.6
Switzerland	40.0
Hungary	36.8
S. Korea	35.3
Bulgaria	32.1

Source: Nuclear Energy Institution (--) Nuclear Energy Institute - World Statistics [6]

Citings:

[1] Nuclear Energy Institute (2008) Nuclear Energy Institute - U.S. Nuclear Power Plants [on-line] http://www.nei.org/resourcesandstats/nuclear
_statistics/usnuclearpowerplants/ (11-06-08)

[2] ICJT (--) ICJT.org - Nuclear Power Plants in the World [on-line]
http://www.icjt.org/an/tech/jesvet/jesvet.htm (12-06-08)

[3] Nuclear Energy Institute (--) Nuclear Energy Institute - State Nuclear Facts [on-line]
http://www.nei.org/publicpolicy/stateactivities
/statenuclearfacts/ (11-05-08)

[4] Patricia A. Michaels (2005) World Nuclear Power Statistics 2004 [on-line] http://greennature.com/article275.html (11-06-08)

[5] Mycle Schneider, Paris and Antony Froggatt, London (2007) The World Nuclear Industry Status Report 2007 [on-line] http://www.greens-efa.org/cms/topics/dokbin
/206/206808.pdf (12-06-08)

[6] Nuclear Energy Institution (--) Nuclear Energy Institute - World Statistics [on-line] http://www.nei.org/resourcesandstats/nuclear
_statistics/worldstatistics/ (11-06-08)

Kaiqing (7) Elvendork!!!

the beauty exposed ;