Thursday, December 23, 2010

Christmas Stasis

I have been extremely busy since last weekend with packing my stuff, graduation, and moving to a new location. I will also be spending Christmas at the home of one of my aunts and so I will be out of town until the twenty-sixth of this month. Because of this, my blog series on nuclear technology will be suspended until next week.

In addition, I will wish you all a merry Christmas in advance. Whether or not you identify as Christian, the holiday should be a joyful occasion. This is because to me as well as many other atheists, Christmas is an important cultural holiday and the values of goodwill, love, peace, and prosperity are just as relevant from a secular standpoint as they are from people who profess belief in supernatural deities.

Who among you does not like a tree full of beautiful lights and decorations? Who would turn his head from the wonderful Christmas dinners, candy and cookies, snacks? How many of us would freely part from the exchanging of gifts that we experience during Christmas? Our relatives and guests might be a bit loud and raucous at times after the wine, beer, and egg nog flows freely but Christmas has a miraculous way of preventing resentment from becoming full-scale arguments.

So, the nuclear reactor and the machines that run my blog will continue to operate all throughout Christmas as they do every day until my return on the 26th where we will pick up where we left off with the plutonium fuel cycle. For those of you who have to travel far, I do hope that the roads are safe and that the TSA does not become too taxing on your nerves with their fraudulent security theaters. In addition, I wish that everybody gets plenty to eat this Christmas and that they get all that they have asked for or wanted this year.

Finally, in order to keep up with the festivities, I have decided to decorate this facility for the Christmas season and play some fitting music. I hope you do not mind listening to Burl Ives, Bing Crosby, and Dean Martin for awhile. Enjoy!

Merry Christmas everybody!

Sunday, December 12, 2010

Nuclear Technology Basics: Part 2 Thorium Fuel Cycles

Introduction

Part 1


Although most nuclear reactors in the world today use fuel cycles based on the element uranium, it is also possible to use thorium as a source of nuclear energy with some types of nuclear reactors. A thorium-based fuel cycle has several advantages over one that is based on uranium, making it an increasingly attractive option to invest in from an energy production standpoint.



Thorium is element 90 in the periodic table. Like uranium, thorium is a naturally occurring actinide metal that is slightly radioactive when found in nature. Although as many as 33 different isotopes of thorium are possible, the thorium that is found in nature is mostly thorium-232. Thorium ores can be found in abundance all across the world, particularly in India and the western steppes of the US. Since there is currently little use for thorium from a commercial standpoint, there has been little effort to exploit these resources.



By itself, thorium-232 is not fissile, but if a neutron source is provided such as uranium-235, it can "jumpstart" thorium-232 into a fission chain reaction by causing it to absorb a neutron and become thorium-233. Thorium-233 has a half-life of twenty two minutes at the end of which it emits an electron, causing it to decay into proactinum-233. After 27 days, proactinum releases a second electron and becomes uranium-233.

232Th (n,γ) 233Th (β−) 233Pa (β−) 233U (n,2n)

Uranium-233 has a higher neutron yield than Uranium-235 when it undergoes fission, and therefore releases more energy per neutron absorbed. The decay of Uranium-233 would lead to the creation of numerous isotopes that would be useful from a medical and industrial standpoint and would be able to breed more uranium-233 within the reactor from the neutron irradiation of thorium-232. From a weapons-proliferation standpoint, the thorium-fuel cycle would be very difficult to divert into making fissile warheads. This is because proactinium can also decay into Uranium-232 which emits hard gamma radiation which is a hazard to people who would tamper with the reactor material in addition to the fact that although it is fissile within a reactor, it interferes with fast fission reactions like those within a thermonuclear bomb.

232Th (n,γ) 233Th (β−) 233Pa (n,2n) 232Pa (β−) 232U

Thorium-based fuel cycles have much in the way of economic potential and could be utilized by using off-the-shelf technology. The US experimented with thorium-based reactors during the molten-salt reactor experiment at the Oak Ridge National Laboratory during the mid-1960s until the project was abandoned in favor of uranium-based light water reactors for political reasons. Russia, China, and India are currently looking into the viability of thorium for nuclear energy production, and India is currently using thorium in its pressurized heavy water reactors (PHWRs) and its liquid metal fast breeder reactors (LMFBRs). Ideally, the full potential of thorium could be utilized in a liquid fluoride thorium reactor (LFTR) but it remains to be seen if the LFTR concept gains enough political momentum to allow it to be commerically realized.

Sunday, December 5, 2010

Nuclear Technology Basics Part 1: Uranium Fuel Cycles

Introduction

Most reactors in the world today utilize the uranium fuel cycle to sustain fission, but there are other fuel cycles as well such as ones based on thorium and plutonium. Light water reactors (LWRs) typically have a once-through fuel cycle in which results in various degrees of spent fuel to be disposed of. Breeder reactors and various reprocessing centers can greatly reduce the quantity and half-life of material to be discarded, but nuclear reprocessing is banned in some countries because of errant political concerns rather than for any technical reason such as is seen in the US.

Uranium is a common element that is found in many locations across the world, usually in the form of Uranium oxide. Uranium oxide is a yellowish-brown powder, and is often referred to as "yellowcake". Large deposits of uranium are found in Australia, Africa, Canada, Spain, Russia, and the US where it is mined and sent to an ore processing center. Uranium mines may be either open pit mines when the uranium is close to the surface, or in underground mining tunnels for deeply-buried deposits. Most uranium in the US and Australia is mined using in-situ leeching methods where the uranium oxide is dissolved from the surrounding rock in solution using water that is acidified by carbon dioxide. A LWR reactor requires around .2 metric tonnes of uranium oxide per megawatt produced for its continual operation.

The uranium isotope, U-235 is the primary isotope of interest for power generation. In chemistry and nuclear physics, an isotope of an element is an atom that has a different number of neutrons from the typical number of an atom from that type of element. Uranium has 33 different isotopes, and all of them are radioactive with varying degrees of radioactivity and half-lives. Only .7% of the atoms in naturally occurring uranium oxide are U-235 on average, while the most abundant isotope of uranium is U-238 which accounts for 99.28% of uranium atoms found in nature. Rarer still is the naturally occurring isotope of Uranium U-234 which is slightly more than half a percent of uranium found in deposits on Earth.

In order for mined uranium oxide to be viable for usage in a LWR it must be brought to a fuel fabrication facility where uranium oxide is converted into uranium hexafluoride where the percentage of U-235 is concentrated up to three percent. This is done either through the gaseous diffusion process or the centrifuge process. In either case, "tailings" are produced as a by-product of the process. Uranium "tailings" are largely devoid of the U-235 isotope and consist mostly of U-238. This "depleted" uranium is only weakly radioactive and has many commercial uses because of Uranium's density, ranging from aircraft counter-weights, radiation shielding, boat keels, and munitions. Although uranium itself has a toxicity comparable to lead from a chemological standpoint, uranium is not easily absorbed by living organisms if ingested. The greatest danger comes from the accidental inhalation of the material if it is finely ground into a powder, because the particles can become lodged in the lungs so respiratory protection should be worn when working with powdered uranium compounds. However this is true for many fine particulate substances and is not necessarily unique to uranium. The fears of "depleted uranium" are largely unfounded and baseless.

When the uranium hexafluoride has been enriched to the desired level, it is converted into uranium dioxide which is a fine powder. The uranium dioxide is mechanically pressed into small pellets for use as fuel within a nuclear reactor fuel assembly. The pellets are stacked within tubes made from a metallic alloy of zirconium and serve as fuel rods in the nuclear reactor vessel.

Within the reactor vessel, the Uranium-235 isotope undergoes nuclear fission. Uranium-235 captures and absorbs a stray neutron to become the unstable isotope, Uranium-236. U-236 commonly decays into isotopes of barium, tellurium, krypton, and zirconium and releases energy and two or three neutrons in the process.



These stray neutrons impact other nearby atoms, causing the process to be repeated. In addition, the decay of the daughter products of uranium can create isotopes of other elements as well. Three of the more common decay chains of Uranium U-235 are represented by these equations:

U-235 + n ===> Ba-144 + Kr-90 + 2n + energy

U-235 + n ===> Ba-141 + Kr-92 + 3n + 170 MeV

U-235 + n ===> Zr-94 + Te-139 + 3n + 197 MeV

Interestingly enough, the atomic masses of the isotopes created from the decay of uranium-236 are usually around the low 90s to the mid to upper 130s because of the law of Conservation of Mass in regards to matter. The total mass of the isotopes resulting from the decay of uranium-236 and the neutrons that are released equals a mass of 236, just like the uranium-236 that they decayed from.

After a year or so, 33% of the fuel rods within a nuclear reactor are removed and the reactor is refueled with new fuel to keep the fission reaction going. The spent fuel rods are submerged in a pool of water within the power plant so that they can cool down long enough for further processing and for some of the more radioactive, shorter-lived isotopes to decay. After a few years, the assemblies containing the spent fuel are taken out to be disposed of.

The fission products that were created during the nuclear fission process can be divided into short, intermediate, and long-lived half-life categories.The half-life of an element is the average amount of time for the atoms within a sample of material to have undergone radioactive decay into another element. Most of the fission products have short half-lives that are less than a year. Although many of these isotopes are highly radioactive, they undergo decay during their period in the spent fuel pool and do not present a problem from waste disposal standpoint. Isotopes with an intermediate half-life can be somewhat problematic as they can range anywhere from a year to a century or two and can emit moderately high levels of radiation such as with the case of strontium-90 and cesium-137. These elements can be transmuted into less dangerous isotopes through further neutron bombardment but it is much more cost effective to simply dilute them with inert compounds to the point to where their radioactivity no longer poses a problem. Isotopes with half-lives lasting longer than three centuries can make up to 20% of the spent fuel to be disposed of, but one must keep in mind the inverse relationship between half-life and radioactivity.

Although the half-life of some of these fission by-products can be up to several billion years, they are only weakly radioactive to the point of being barely above the background levels of radiation that all of us are exposed to in our daily lives. As a case in point, potassium-40 has a half-life of 1.3 billion years, and it can set off alarms from radiation detection equipment. However, it is quite abundant in foods with large amounts of potassium in them, such as bananas and it is also found in our bones. However, it is very weakly radioactive as a person only gets an exposure of a few picocuries per year. Eating one banana a day for each day in a year would increase your exposure to radiation by 3.6 milirems per year and the average person receives several hundred milirems per year from naturally occurring background sources with no ill-effects.

Exposure to Radon Per Year By County (Red means high levels of radon)



New Cases of Cancer Diagnosed Per Year By County (High rates are purple)



In countries such as France that use nuclear reprocessing the useful isotopes are separated from the spent fuel assemblies. Since over 90% isotopes within a spent fuel assembly consist of un-fissioned uranium-235, and fissionable plutonium-239 this greatly reduces the volume of the material to be disposed of. The material from a spent fuel assembly can be reduced through reprocessing to a piece of material the size of a cigarette lighter with a half-life of three centuries. The fuel created from this process is known as mixed-oxide fuel, or "MOX" fuel. There are many different types of fuel reprocessing. The most common type is the PUREX method, although research is being conducted into "pyroprocessing" techniques.

Unfortunately, it is often politics that drive policy not common sense and the US is no exception. Although the once-through spent fuel disposal method is wasteful from the standpoint of throwing away a source of useful nuclear fuel, there is not much of it at all. There are three categories of "nuclear waste"; low-level waste, intermediate waste, and high-level waste.

Low-level waste consists of anything from pens and pencils from the offices within a nuclear power plant to the gloves and protective gear worn by personnel. Low-level waste from a nuclear power plant is often very weakly radioactive if it is radioactive at all, and is typically burned or buried close to the surface of a special landfill. Intermediate waste includes things like the actual components of the reactor itself in addition to the materials used in the construction of a nuclear reactor. There is usually not much in the way of intermediate waste to be disposed of and it is often buried in a shallow repository. High-level waste consists of the spent fuel that is marked for disposal.

This material is a metallic solid that has been encased in glass, lined with concrete, and sealed into an extremely durable cask. Tests have demonstrated the ability of these casks to withstand impacts with freight trains. Doomsday scenarios featuring terrorists stealing spent fuel material in order to construct bombs leave out the fact that the concentration of Uranium-235 needs to be enriched up to at least 90% for it to be weapons-grade material. Spent fuel does contain plutonium-239 which can be used for a plutonium bomb, but it is also contaminated with plutonium-240 which is a poison for a nuclear bomb as it absorbs neutrons without fissioning, effectively stealing the neutrons that would be able to strike plutonium-239 that would cause the rapid fission reaction. Fission would occur, but not in the rapid fashion that you would need it to for a nuclear bomb. To make things worse for a terrorist, it would be very difficult to separate the plutonium-239 from the plutonium-240 and it would require highly specialized equipment. It would simply be cheaper and easier to build a special reactor dedicated to producing weapons-grade material like most nations do.

Finally, the amount of high level waste to be disposed of is quite small. All of the high-level waste ever produced in the US as a by-product of nuclear energy could easily fit into a room the size of a high school gymnasium, just two stories high. Compare this to the mountains of coal ash and carbon dioxide generated by the burning of fossil fuels which will be just as toxic millions of years from now as it was the day that it was created.

In part two, we will be taking a look at thorium-based fuel cycles and how nuclear reprocessing works in detail. I hope that this post was easy to read and understand and that it was not too long or boring. Stay tuned!

Sunday, November 28, 2010

Nuclear Technology Basics: Introduction (Fun With Fission)

Well, I have just returned from Thanksgiving break. As promised, I will begin a series of posts concerning nuclear reactor technology and how different types of nuclear reactors differ from one another. In the near future, I will also include a glossary entry on my blog that people can reference at a later date in case they come across terminology that is not clear to them.

At the most basic level, all thermally-based power plants share the same mechanics of how they generate electrical energy. A heat source is used to generate steam, which causes a turbine to spin from the pressure provided by the steam which is being used as a working fluid. The action of the spinning turbine is connected to a generator which converts mechanical energy into electrical energy by the rotation of the turbine. Coal, oil, biomass and natural gas facilities use the combustion of these fuels to provide heat to create steam while solar thermal power stations use light from the sun and convert it into a source of heat. Geothermal energy is also thermally-based because it relies on heat from under the ground in geologically active regions in order to operate. Non-thermally based methods of electricity generation such as wind, hydroelectric, and wave energy turbines are directly spun by the movement of wind or water. Photoelectric solar stations generate electricity from solar cells using the photoelectric effect.

In the case of nuclear energy, heat is harnessed from a sustained nuclear chain reaction to drive a steam turbine. Nuclear reactions concern the interaction of an atom's nucleus with the nuclei of other atoms. Heat and subatomic particles are often produced as a result of a nuclear reaction, depending on what type of nuclear reaction it is and what elements are involved. A nuclear chain reaction is when the products of one nuclear reaction trigger additional nuclear reactions within a whole group of nearby atoms in a positive feedback loop. There are two main types of nuclear chain reactions, nuclear fission and nuclear fusion.

Nuclear fusion is when the nuclei of a pair or more of atoms become fused together. The fusion of the atoms releases large amounts of energy. Nuclear fusion is what powers stars in space and has also been achieved within a human laboratory. While nuclear fusion could hypothetically be used as a source of terrestrial power, this has proven to be quite difficult. Surrounding each atom is a positively charged field known as the electrostatic force that tends to repel other atoms away before a pair of atoms can become close enough for their nuclei to fuse. It requires massive amounts of energy to overcome the repulsion of the electrostatic forces between neighboring atoms. Although the development of a nuclear fusion reactor has been a high priority for many governments around the world for many decades, nuclear fusion reactions being carried out in a laboratory have yet to result in a sustainable fusion chain reaction as it seems to require more energy to cause atoms to fuse than what is actually released during the fusion process when attempted on Earth. Because of this, it is likely that a working fusion reactor is still many years away from being a reality.

Nuclear fission is the second type of nuclear chain reaction. It is basically the process of causing atomic nuclei to fragment by ramming them with subatomic particles, which in turn causes the subatomic particles that result from the fragmented nuclei to crash into the nuclei of other atoms and repeat the process. Fission reactions produce heat and other forms of radiation depending on what the products of the fission reaction are. Since the successful operation of the first fission reactor in 1942 at the University of Chicago, all reactors that have been built by humans have been fission-based. Interestingly enough, the existence of naturally occurring fission reactors has also been observed in nature such as the Oklo fossil reactors in Gabon, Africa where the isotopic ratio of uranium deposits within the area allowed nuclear fission to sustain itself. In addition, the georeactor theory in the geological field postulates that the Earth's magnetic field and the heat that is produced from its core might arise from the activities of a naturally occurring reactor in its interior similar to what has been seen at Oklo. However, the georeactor theory has little in the way of evidence that supports it at this time although this may change in the future.

That is enough for now, as I do not want to get too long-winded with each post. The next part of this series will be a look at the basics of nuclear fuel, reactor design, and the fuel cycle itself. Feel free to ask any questions that you might have.

Thursday, November 25, 2010

Thanksgiving Day Post

Today is Thanksgiving, which is an important holiday in the American calendar. Although Thanksgiving is said to commemorate the feast that the Native American tribes had with the early puritan colonists, the actual holiday itself was not established until 1863 by president Lincoln during his Thanksgiving proclamation. Up until then, many states scheduled their own "thanksgiving" events as an irregular observance, often during years when there was an especially bountiful harvest.

A magazine editor by the name of Sarah Josepha Hale wrote a series of letters to president Lincoln urging him to declare Thanksgiving as an official holiday. America was being torn apart by civil war and Mrs. Hale felt that nationalizing the custom of thanksgiving would help restore a feeling of unity throughout the US. The holiday was vaguely based on the Puritan harvest festival at Plymouth Plantation during 1621, which lasted three days from late September to early October. However, the idea behind Thanksgiving as set forth by Mrs. Hale was more of a celebration of "home and hearth" before the dead of winter rather than a specific historical event.

Since the Thanksgiving proclamation, Thanksgiving has been a national holiday that is celebrated on the last Thursday in November. Although the Puritans were more than likely eating venison at Plymouth, turkey is traditionally eaten on the holiday because West Point students were customarily served turkey during Thanksgiving, which had generally been a northeastern culinary tradition until then. Because of this, many West Point troops had been exposed to turkey, which helped cement its place on the Thanksgiving dinner table. After the end of World War II the famous Norman Rockwell image of a roast turkey serving as the symbol for "Freedom From Want" made turkey the national icon for Thanksgiving.

I myself had an enjoyable Thanksgiving today. The turkey was roasted upside-down to make sure that the breast area does not become desiccated during the cooking process. The dog, myself, and everybody else had plenty to eat and everybody seemed to have a good time. My favorite cut of a turkey is the leg or "drumstick" as I prefer dark meat to white meat when it comes to poultry flesh. The "white meat" on birds consists of fast-twitch muscle fibers, which are used for short bursts of intense activity, while the "dark meat" contains slow-twitch muscle fibers, which are mainly meant for sustained physical activity. Slow-twitch muscle fibers contain more myoglobin, which is a protein in muscle tissue that gives it a darker color.

I wish everybody an enjoyable Thanksgiving and I hope that they make sure they get enough to eat and that the company of their dinner guests is not too trying on their patience. The best part of Thanksgiving is often the leftover food the day after, as it is just as good if not better than the day before. Finally, one must not underestimate the remaining turkey skeleton, which is highly valuable for making soup stock out of after the last of the meat has been picked off by ravenous humans.

Happy feasting everybody!

Tuesday, November 23, 2010

All Fission Reactors Are Not Created Equal

For the next few days or so, I will be taking a look at the different types of nuclear reactors that have existed or have only been theorized about on paper. The reason being is that there are so many different potential reactor designs that it is often confusing to people outside of the field of nuclear engineering to determine how reactor designs differ and what the pros and cons of each design are. To make matters worse, the names of these reactors are often abbreviated to different acronyms making it even more difficult for laypeople to understand what the different terms mean.

This will be a bit of an undertaking, as there are literally hundreds of different reactor designs. Some have only existed on paper, others were only experimental prototypes, while others have been built but have since been decommissioned, either from age, lack of economic viability, or from politics. Although some reactor types are highly impractical or dangerous and have rightfully been consigned to the dustbin of history, there are some designs that would have been quite impressive from an economic and commercial standpoint.

At the moment, I am wondering how to proceed in terms of how I will talk about this. I am leaning towards a series of posts, with each post concerning a different "family" of reactor types based on what they use as their moderator materials. However, I am open to ideas from anybody who might offer suggestions.

Monday, November 22, 2010

Nuclear Energy in Asia is Going Full Steam Ahead

India has started construction of a new nuclear facility in Gujarat. It will be a pair pressurized heavy water reactors (PHWRs) that will generate 700 megawatts each. Planning started in January of this year after the site for the reactor was excavated within a short time frame of four months. Construction began today, and the reactor is expected to be online by 2015.

If India can do this, then why should it be so difficult to build new reactors in Europe and the US?

Possible New Reactor in Green River, Utah

The Emery County corporation has started to push the limits of its current energy infrastructure in Utah. Because of this, there has been a serious effort to construct a new nuclear facility near the town of Green River. The planned design would be a power plant with a pair of reactors that would generate 1,500 megawatts each. The nuclear powerplant would be a boon to the nearby community as well as the state of Utah with the positions that it would be able to offer people in its construction as well as its operation.

However, the plant has met opposition as opponents have attempted to prevent the facility from getting rights to water from the Green River that would be used for cooling. Most of the water that is circulated within a light water reactor is then returned to its source, while only a small amount of water is actually evaporated during the cooling process.

If this planned reactor goes forward, it would mark the first time since the 1970s that the construction of a new nuclear reactor was completed. If this project is successful, it might help revive nuclear energy in the US by encouraging the construction of new reactors in other locations. In any case, this is a promising sign that the "nuclear renaissance" will be more than just words.

Sunday, November 21, 2010

First New Uranium Mine in Years

Phase I of the South Texas Palanga uranium mining project has been completed by the UEC (Uranium Energy Corporation) under-budget and on schedule. Phases II and III are expected to be completed in 2011. This marks the first time in several years that uranium demand has allowed for the opening of a new mining facility. Mining operations will commence using in-situ leeching methods, where water that has been acidified with carbon dioxide gas will be pumped into the mining site. This is what allows the uranium to be extracted from the surrounding limestone as the uranium is dissolved in the water when it is pumped out again during mining operations.

The economic activities of the uranium mining industry have been depressed for years because of the lack of demand for nuclear energy in the US since the mid-1980s. In the early 2000s the price of uranium bottomed out and it has only been in the last three years that the uranium market has been showing signs of recovery. As the price of uranium has increased since then, there has been a renewed interest in re-opening old mines and prospecting for new sources of high-grade ore.

Many people raise fears that the world supply of uranium will peak in 80 years. One must keep in mind that this estimate is based on existing production rates of uranium ore and nuclear fuel fabrication. There are many mines across the world that have been forced to close either through political pressure, or because existing world uranium demand could be easily met by a smaller number of mines. The amount of uranium required by most reactor types is quite small, especially when compared to the fuel consumption rates of fossil-fuel generators like coal and natural gas. The fissile isotopes of uranium are extremely compact compared to other energy sources. A single fuel pellet like those used in a nuclear reactor is the equivalent of 1,780 pounds of coal from an energy standpoint. Although hundreds of these pellets are used to fabricate fuel rods in a light water reactor, the amount of uranium required to fuel a reactor is still a rather tiny amount.

In the event of a large build-out of new nuclear reactors, it would not be too difficult to increase the production of uranium ore to meet an increased demand since uranium is such a common element. However, up until now there has been little need to do so. In fact, should the easily recoverable sources of uranium ever run out like the most dire scenario erroneously predicts, existing stockpiles of spent fuel could easily be reprocessed for more fuel. Finally, uranium can be extracted from seawater. Although the cost of recovering uranium from using this method would be roughly ten times conventional mining methods, it would still be economically viable as the operational costs of nuclear electricity generation are relatively insensitive to price increases of fissile material.

Friday, November 19, 2010

N^4 Has Been Redesigned!

I thought that my layout for N^4 was getting a bit stale, so I overhauled it. It turned out better than I thought. The new options for Blogger also allowed me to get rid of that damn space between my blog articles and the sidebar that Firefox kept insisting on doing for some reason. As a bonus, I also put in a new header image.

Monday, September 20, 2010

Potential New Markets for Nuclear Energy

Part of the slowly emerging interest in nuclear power has been taking a look at regions of the world that would be especially suited for building new nuclear reactors. Several countries in the Middle East such as Bahrain, Jordan, Kuwait, Oman, Qatar, Saudi Arabia, and the United Arab Emirates have expressed interest in having nuclear energy programs. Iran has also been the focus of much news as of late over concerns that its current goal to expand the role of nuclear energy in its energy infrastructure might be a front for developing nuclear arms. However, the process of creating fissionable material for warheads is quite different than the process of generating electricity and a nuclear weapons program would be difficult to keep hidden.

In any case, the middle east would be well-served to invest in nuclear energy as many countries in the region depend heavily on fossil fuels for electricity generation which has negatively impacted the environmental and human health in the region in addition to complicating its political identity. In addition, many people within this area of the world live in arid conditions making agriculture, animal husbandry, and access to water for human consumption difficult. Part of the interest in nuclear energy in the middle east has been driven by its potential application for desalinization. Thousands of gallons of freshwater could be created daily from seawater using the waste heat from a nuclear facility for the fraction of the cost of other desalinization procedures.

In the British isles, Britain has been seriously considering new nuclear development as many of its existing nuclear facilities are aging as no new nuclear facilities have been built in years. This reflects a similar situation as we have seen in the US. As coal and natural gas have major drawbacks in regards to pollution from carbon dioxide and in the case of coal; ash and soot, the British government has started to re-evaluate the viability of nuclear energy in Britain's energy portfolio. Ireland has traditionally been vehemently against any sort of nuclear development choosing to rely on burning peat, low-grade coal, and imported natural gas. The rapid pace of economic development has lead to considerable demand for more energy in the nation, and Ireland has been mulling over the potential of nuclear energy to alleviate a potential energy shortage. Although anti-nuclear sentiments remain strong in the country, this may change as people become more educated about the inherent safety of nuclear energy as well as its minimal environmental impact. This is especially poignant when considering the amount of pollution that the burning of peat and fossil fuels causes when Ireland has recently become concerned about its environmental health.

Australia remains an important source of uranium yet its traditional stance against nuclear energy has prevented any reactors being built and has chosen to largely use coal for energy instead. The impact of Australia's large coal mines have scarred the landscape. The amount of carbon dioxide and particulate matter produced from Australia's coal plants is immense, especially when one considers that some of it is also very low-grade lignin which is even more polluting than bituminous coal when burned. To make matters worse, various "environmentalist" groups have recently put pressure on Australia's government to limit uranium mining and exploration yet remain strangely silent when it comes to the continual operation of Australia's coal infrastructure. There have been calls in Australia for the development of nuclear energy but it remains to be seen if Australia's defacto ban on nuclear energy will remain for the future as many countries in Europe have either lifted or stalled their moratoriums on nuclear energy.

Finally, Asia has been aggressively expanding its investment in nuclear energy, particularly China, Korea, and India. These countries are poised to be the leaders in new nuclear technological development as the nuclear energy market in the US has stalled. Although there has been renewed interest in building new nuclear reactors in the US, it pales in comparison to the rapid degree of nuclear development in Asia.

Friday, April 2, 2010

Nuclear Energy in Africa

It looks like Africa is showing a growing interest in investing in nuclear energy. Although many African countries have been plagued with political problems that have made stable economic development difficult, a thriving nuclear sector would be a boon to the continent and might help it overcome its economic hurdles.

Several African nations attended the International Conference on Access to Civil Nuclear Energy held in Paris and appear to be willing to work with France to expand their nuclear infrastructure. Nuclear energy is capital intensive but it has the advantages of reliability, high efficiency, in addition to all of its costs being upfront instead of being hidden like with fossil fuel-based energy.

Unfortunately, nuclear energy does not qualify for carbon credits through the "Clean Development Mechanism". This is largely a political position by the organization as these carbon credits can apparently only be used to build other forms of renewable energy such as wind turbines and solar plants. However, as nuclear energy is virtually a carbon-free energy source this is an unfortunate omission. An argument can be made that nuclear energy releases carbon dioxide during the construction and mining phases, but this is minimal and still less than the amount of carbon dioxide that is released during the construction of wind turbines and solar panels. Additionally, nuclear energy produces much more energy and requires much less land than a wind farm or a solar plant. Finally, the materials used in the construction of solar panels often contain toxic substances in addition to rare elements. This makes the anti-nuclear position of the Clean Development Mechanism grossly inaccurate.

Thursday, April 1, 2010

My Eyes Have Been Opened!

I have seen the light! Gaia came to me in a dream last night and told me that she was the mother goddess and that nuclear power was poisoning the Earth and destroying the ecosystem! She showed me apocalyptic visions of the future in which humanity was reduced to roving bands of miserable survivors after the environmental holocaust. The few people that were left had taken to scavenging what remained of the land while defending themselves from attack by raiders.

I cried from the pain of the vision that the mother goddess showed me and prayed to her that it would not come true. I have decided to become a wiccan and worship Gaia. I am now a strict vegan and promise to only buy and wear green products and organic foods. I hope to make most of my clothing myself out of hemp, but even if I do need to buy clothing, it will be eco-friendly. Even my underwear will be green. I am going to drop out of school and live independently of the grid, using decentralized wind and solar energy. It is unlikely that I will become ill because I will not be ingesting toxins in my food which are ubiquitous in the western factory-farming industrial complex. However, in the rare event that I do get sick, I will not support the western medical establishment by going to a doctor. Instead I will use alternative medicine such as homoeopathy, enemas, and ear-candling to flush the evil, disease-causing toxins from my system. I was vaccinated as a child so I might get cancer as the damage has been done. But I hope that I will be able to prevent it by tapping into my Chakra centers and realigning my aura.

My days of being brainwashed by big energy and big agriculture have ended. I hope that other people will learn to follow my example which I will promote in various green blogs, chatrooms, and Internet forums of a low-energy, sustainable future. The basic layout of this blog is not going to change much since it is already the color green but I will edit my links and blogroll to feature more ecofriendly news sources and websites. I wish to make up for my days of being an agent of Big Nuclear and the large amounts of money that they have given me to support its agenda. Remember, my friends...use negawatts, not megawatts!

APRIL FOOLS!!

Sunday, March 28, 2010

The State of Nuclear Medicine and Research

Aside from energy generation, another useful aspect of nuclear fission is its ability to produce isotopes for many medical and industrial uses. Reactors that are designed to create these isotopes are typically called research reactors as they do not have much in the way of power output compared to their cousins, the dedicated nuclear power plants. However, isotopes such as technetium-99, chromium-51, gallium-57, etc. must be produced in research reactors by radiating parent isotopes and many research reactors are also used for nuclear scientific testing.

Unfortunately, many research reactors are badly in need of an overhaul as the world demand for radiopharmaceuticals has increased over the years and the number of these specialized reactors still operating has dwindled as many of them are shutdown over hysteria or age. The few that are still operating are running at full tilt and the increased stress on their components is causing them to wear out even faster and many research reactors are badly in need of major repairs. However, to temporarily shut down a research reactor usually means that it is depriving people of valuable isotopes that are needed for many medical procedures and tests. The shortage of research reactors across the world also means that ones that are still operational have to balance their obligations between isotope production, and the queues of researchers that have lined up to use the reactor for experiments and have been waiting for several years to do so.

The Depleted Cranium blog has an excellent post on the status of this phenomenon and the history of how the world came to be in this mess. Research reactors have not been immune to the same idiocy and short-sightedness that has surrounded nuclear power generation and they have also suffered because of it. The construction of new nuclear research facilities should be a world top priority because both science and peoples lives are being endangered with the status of our current situation. I whole-heartedly recommend that my readers visit the post on Depleted Cranium as it really does show how dire the situation is.

Thursday, February 18, 2010

Tuesday, February 9, 2010

Is Nuclear Power a Terrorist Target?

Not likely.

Nuclear power stations are extremely durable buildings that have been constructed to withstand earthquakes, low flying aircraft, and even dedicated artillery might have a difficult time cracking the containment dome. This is because containment buildings are solid reinforced concrete several feet thick. Concrete is known for absorbing explosive force and can also withstand a high degree of compressive force. Even if the containment dome was breached, it would be extremely difficult to shut down all of the safety systems in order to trigger a nuclear meltdown. Even so, the resulting damage and death toll would be quite disappointing for terrorist purposes.

Terrorists are not stupid and would probably much rather choose a target that was easy to damage or destroy in addition to causing massive collateral damage or a large death toll using limited means. Hospitals are prime targets, and in the energy field, nuclear is not necessarily unique in the destruction that could result if a power station was targeted. As seen in China, a broken dam could cause property to be flooded out for miles leaving thousands of people either dead or displaced like what happened in the infamous Banqiao dam disaster in 1975. This dwarfed the amount of casualties that resulted from Chernobyl yet Banqiao has largely gone unnoticed by the public while we still treat nuclear power as inherently dangerous. Terrorists could just as easily target (As well as being much easier) a hydroelectric facility or even a natural gas plant and it could have major consequences for the surrounding area.

Recently, a natural gas plant in Milford, Connecticut exploded resulting from an accident while workers were doing a routine purging of air from its pipelines. Five people have been confirmed dead and the total damage caused is still being estimated and the rubble is still being cleared from the area. Although this was caused by an accident, an explosion of this nature could just as easily be triggered by a hidden bomb planted by a terrorist.

"This is the most devastating explosion and collapse that I've ever responded to," Zak said. "Some of the structural engineers on our team compared it to the L'Ambiance Plaza collapse in Bridgeport, but that was an entirely different type of incident." That 16-story residential structure, under construction, collapsed in 1987, killing 28 construction workers.


Why is nuclear energy unfairly targeted with labels such as "dangerous" and "unsafe" when examples like this hardly ever become major news stories. Every time there is even a relatively minor incident at a nuclear facility, media sources panic as if it was some sort of impending disaster. Yet a brief glance at energy related accidents world-wide would prove otherwise.

In fact, the annual nuclear-related deaths per terawatt is even lower on average than that of wind power!



Also, look at the statistical difference in impact when looking at coal power and nuclear power side by side.




Why do we need to pick on nuclear power so much?

Tuesday, January 26, 2010

The ADS Reactor

I do not know much about the ADS (Accelerator-Driven System) reactor, but I have heard it mentioned by a small group of supporters from time to time. I would like to know more about it if possible. The basic principle is one of a sub-critical reactor core that produces free neutrons during the process of spallation, but I am not sure what the spallation process would theoretically be. Finally, I have heard about the ADS reactor reducing the amount of actinides produced but I am not sure what the quantity of leftover material to be disposed of would be compared to that of the traditional LWR.

How does the ADS design stack up to the LFTR and would it be worth pursuing in favor of the LFTR? Does it also have a high enough operating temperature that can be used as process heat for the synthesis of many chemical compounds like the LFTR and VHTR? Where is the research in the development and construction of such a reactor as the ADS? How much would it theoretically cost to build one? Does it have the scaling problems that many reactor designs do?

If anybody knows the details of the ADS reactor, feel free to tell me, as I am eager to learn more about it.

Monday, January 25, 2010

Thorium Comic

This is interesting. The Energy From Thorium blog posted a webcomic regarding thorium energy. Take a look

Friday, January 22, 2010

An Obscenely Bad Idea

Normally I try to keep my views on politics that are not related to nuclear energy and other technological and scientific developments off of this blog, because I feel that N^4 is not the place for that sort of thing. However, I feel I must speak up about the most recent ruling by the US Supreme Court regarding campaign contributions by corporate interest groups. In effect, it has ruled that there is no cap or limit in terms of how much a company can spend on an election campaign to influence its outcome. The amount of corporate influence in our country's major elections is already intolerable, and now this practically a validation that the voices of corporations are more important than the rest of the voting public. As it is, many of our political "representatives" are already bought and paid for as they effectively do the bidding of who ever has the deepest pockets. In this case, it is almost like the equivalent of applying a thick layer of grease to the highway to hell as we are all forced to ride it through its inevitable downward spiral.

I have had some doubts that our political system was up to the task of looking after the welfare of our nation's citizens, but this ruling has made its inherent dysfunction blatantly obvious. Prior to this ruling, I have also kept my views on healthcare off of this blog because I felt it was a subject that was best left untouched as my blog is not normally meant to be a political soapbox. However, I have been following the whole debate with a feeling of rising anger as I saw how people that were elected to represent us were fully prepared to deliver us bound-and-gagged to the very corporate racketeering scheme that people were seeking shelter from. Needless to say, my confidence in my government has largely taken a complete nosedive after my trust in it had already been languishing for years.

The implications of this ruling are obvious. It takes the first amendment and places it for sale to the highest bidder as it says that free speech can now be bought and sold like any other commodity. Those with limited financial means are now considered to be "less free" as they would not be able to afford to purchase as much "freedom" unlike some of our well-heeled corporate representatives. Our political system is broken, and evidently beyond repair at this point as it has largely resisted any attempt at reform.

So, once again I apologize to my readers for the brief outburst of indignation but this has made me very angry indeed. It does not matter whether you consider yourself a conservative or a liberal at this point your right to free speech has been given a price sticker. Unless you can afford to buy up all of the media outlets, thinktanks, and funnel soft money to political candidates, your first amendment rights have now largely been revoked. We might as well dress up in our new company-issued uniforms complete with a ball gag and handcuffs and bow before our corporate overlords. Our Supreme Court has failed us all.

Tuesday, January 19, 2010

Changing Minds, but is it Enough?

When I started this blog two years ago, it was out of a combination of frustration and anger at how quickly people dismissed nuclear energy like it was some sort of arcane and unholy type of technology. Even though the facts were otherwise, many people still opposed it tooth and nail as they either ignored the benefits or thought that the data itself was part of some sort of conspiracy promoted by "Big Nuclear". I was never against nuclear power at all, even when I was relatively misinformed about it but I did have some reservations about what to do with the spent fuel as I like many other people thought that it was dangerous and difficult to deal with. However, I still thought that was magnitudes better when compared to coal and natural gas. As these fuel sources were very dirty indeed and as it was the late 20th, early 21st century I thought that it was ridiculous that we were still depending on fossil fuels as our main source of energy. Yet I also knew that wind and solar power lacked the energy density and reliability to be able to produce the amount of electricity on a regular basis that a developed country like the US needed.

Then my eyes caught an article in Scientific American around 2005 talking about nuclear energy and what sorts of reactors could be built and the pros and cons of the different designs. I was fascinated as I read about designs that could be used to breed more fuel or greatly reduce the quantity and half-life of existing stockpiles of spent fuel as well as close the nuclear fuel cycle to ensure a virtually infinite and environmentally friendly source of energy. I also began to grow very angry, as the only thing holding nuclear technology back seemed to be a combination of NIMBYism, fossil fuel interests, and just the overall lack of will that would be needed to restructure our energy producing infrastructure.

I began to research nuclear power online as a hobby in addition to reading whatever I could find on it in various books and publications. My amazement was underlined by seething anger at how the US had let coal and natural gas expand and entrench themselves over the decades as we had not built a new nuclear reactor in this country since the 1970s. Our back was turned on nuclear power out of a combination of fear, pointless bureaucratic redtape, and the canceling of many planned reactor projects after the oil crisis thirty-seven years ago. This was all due to politics and scaremongering rather than a legitimate reason to condemn nuclear power.

This was a direct reversal of the attitude that characterized the previous two decades as nuclear powerplants were being built at a rapid pace and nuclear reactors were quickly adapted to be used for naval use. The cold war and a feeling of optimism towards nuclear science and technology spurred rapid development in this field and it also threatened to put coal power out of business. However, the nuclear industry was practically moribund by the early eighties through a misinformed but successful campaign against nuclear energy that had grown out of the fear of nuclear warfare and was helped along by fossil fuel lobbyists and their paid off politicians. Ironically, nuclear power has had the best safety record of any energy sector in the US and even across the world yet it had been rejected in favor of coal which kills thousands of people worldwide through its normal operation.

After seeing the ridiculous comments and hysterical fears surrounding nuclear power being touted by various "environmentalists" I decided to create this blog in the hopes of taking an honest look at nuclear power. This was part of an effort to help people realize the environmental benefits of an infrastructure largely based on nuclear energy as well as the fact that nuclear power is the only clean form of energy that can be used practically anywhere on earth and deliver a constant supply of energy regardless of weather conditions. Scaling back production and energy usage would never be the answer because as we increase our technological development, the demand for energy increases. However, it is through more technology, not less that we can hope to make a better world for everyone. The past is gone, but trying to revisit the past by rejecting technological progress would be foolish because the "past" presented by various primitivist and neoluddite groups is based on a highly idealized and impractical vision of what previous generations of humanity really faced. Ironically, the popularity of these movements has been aided by the technology brought to them by the internet and computer revolution. I would very much doubt that humanity would want to go back to the days before running water, electricity, heating, cooling, hygiene, sanitation, and modern medicine. We can thank all of these previous comforts for our greatly improved lifespans. A few hundred years earlier, a middle-aged man or woman of 40 would be considered elderly.

As I look around, I see that people are slowly starting to realize that nuclear energy is not nearly as bad as various sources portray it as being. There is a lot of misinformation and outright lies regarding nuclear technology as there are many organizations that have made it their business to vehemently oppose nuclear power on all fronts, especially when they have or are allied with entrenched fossil fuel interests. I have a cautious degree of optimism as I watch people starting to push back against this tide of nonsense and hope that we can start looking forwards to a clean, energy rich future again as nuclear power is the only option that we have that can deliver on this promise. We need to get the liquid fluoride thorium reactor development path up and running again after its cancellation during the early 1970's as this design shows a stunning degree of versatility and efficiency at practically little to no cost to the environment.

Saturday, January 16, 2010

AREVA Discussion

Yes, I had my AREVA conference call in the morning yesterday, and it turns out that AREVA is stepping up its efforts to start building more EPR (European Pressurized Reactor) and PWR (Pressurized Water Reactor) type reactors in the US. In addition, they are heavily pushing the VHTR (Very High Temperature Reactor) for the GenIV research path in the US in addition to the GCFR (Gas-Cooled Fast Reactor) in Europe, particularly France. Currently, AREVA has no plans to develop any thorium based reactors.

Although the VHTR would not be my first choice for the GenIV development path, it does have its advantages in the fact that it would utilize a much higher actinide burn up ratio in addition to being more efficient in terms of power output to fuel usage. Finally, one of the main reasons why AREVA is pursuing the VHTR is because of the high amount of heat that the reactor gives off during its operation that can be put to use for many industrial applications ranging from hydrogen production, petroleum distillation, and desalination. AREVA mentioned that one of the main challenges that they foresee is getting the design approved through the NRC, which is a notoriously fickle administration. The GCFR has been chosen for Europe because of the political viability of a closed nuclear fuel cycle which has traditionally met with some difficulty in the US. GCFR reactors can use many different fuel grades for energy including material that is left over from the operation of LWR (Light Water Reactor) and PWR reactors. The GCFR can be used as a breeder and it operates at a high enough temperature in that it can take advantage of the Brayton cycle.

It was a very productive and interesting meeting and I am glad that I was able to attend as I no longer have a class during Friday morning. I look forward to next month's topic and hope that this is going towards a greater role and acceptance of nuclear energy in our future. Once again, I thank AREVA for their time and efforts.

Monday, January 11, 2010

AREVA Conference Call

AREVA is hosting another conference call this week. It has been awhile since I have been able to attend one of these but I have had a Friday class last semester that prevented me from participating. Now that I no longer have any classes scheduled on Fridays for this semester this is no longer a problem.

I will put up a follow up post regarding the subject of the conference call and what I have learned for those of you who are interested. Once again, I have an opportunity to learn what is going on in the nuclear industry from inside experts. I am excited.