Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Strategies & Market Trends : The Residential Real Estate Post-Crash Index-Moderated -- Ignore unavailable to you. Want to Upgrade?

To: Travis_Bickle who wrote (11747)	3/15/2011 10:37:15 AM
From: The Reaper	1 Recommendation Respond to of 119361

Graph of path of devastating nuclear fallout, grab your ankles California In that case people will be staying indoors and watching movies. Maybe NFLX is the best place to be right now. Must be what triggered the buy from Goldman.

To: Travis_Bickle who wrote (11747)	3/15/2011 1:16:34 PM
From: stockman_scott	Respond to of 119361

Jimmy Chowda Says: Former nuclear reactor operator here and this is idiotic beyond comprehension. You can’t get a nuclear explosion, one that would create a fallout cloud, from a reactor like this which is shut down. The “meltdown” that is occurring is warping of the fuel due to decay heat, rendering it useless for further operation. The catastrophe is a financial one, not one of widespread environmental harm. The explosion was from hydrogen and/or oxygen coming out of the coolant (i.e. water) due to experiencing a sharp decrease in temperature, or from when they intermittently vented steam from the plant to relieve pressure. Chernobyl exploded because they performed shutdown maintenance on a critical reactor, instantly inserting an insane amount of reactivity. The NRC would have you fired on the spot for attempting to perform something like that here and you would likely see jail time. Same goes for the nuclear sailors on carriers and subs. Again, there cannot be a nuclear explosion from this. March 13th, 2011 at 5:27 pm ________________________________ Nevada Paleocon Says: The Sky is falling! The sky is falling! To compare the nuclear reactors in Japan with the Chernobyl-type reactor is DISHONEST and IRRESPONSIBLE! Could a Chernobyl-type reactor meltdown happen in the US or Japan? Almost impossible. The vast majority of nuclear engineers would answer this question with an emphatic “NO”. The U.S. has over 100 operating commercial nuclear power plants, more than any other country, and many of them are near large population centers. There are a number of significant design and operational differences between the Chernobyl-type reactors (RBMK) and U.S. and Japanese commercial light water reactors (LWR) that make a Chernobyl-style disaster essentially impossible. To understand the differences, one needs to know a bit about how reactors work. Once one understands the basics of reactor design, one can then identify the main similarities and differences between the reactor types and assess the prospects for a “Chernobyl” in the U.S. There are two types of reactors used in the U.S. and Japan for the production of electricity: the Pressurized Water Reactor (PWR) and the Boiling Water Reactor (BWR). Both of these types use ordinary water as both coolant and moderator, and therefore are known as Light Water Reactors (LWR). NOTE: Chernobyl was a type of reactor called an RBMK (Russian acronym) which uses a graphite moderator and water coolant. Similarities: The RBMK and a typical U.S. LWR are both thermal reactors that burn uranium dioxide fuel. By thermal it is meant that the neutrons that are emitted by the fissioning atoms must be slowed down to low (thermal) energies so that they can cause more fissions. The heat that is generated in this process is carries away by the coolant which, for both reactor types) is ordinary water. This heat is used to make steam which is then used to drive turbo-generators to make electricity. The rate of the reaction is controlled by inserting control rods into the core. The large amounts of radiation produced under normal operation are contained within the core by heavy concrete and steel shielding. Differences: There are a number of major and minor differences between the RBMK and U.S. Light Water Reactors. The fuel assemblies in the RBMK are contained in individual pressure tubes, whereas one pressure vessel contains all of the assemblies in an LWR. The reason for the RBMK design is so that assemblies can be loaded and unloaded individually without shutting down the reactor. This is an advantage if the reactor is to be used for both *****nium and electricity production. LWR’s must be shut down for re-fueling and therefore the fuel is kept in as long as is economical. Water acts as both coolant and moderator in LWR’s so that a loss of coolant also stops the fission reaction. In the RBMK, the moderator is solid graphite and the water coolant acts as a poison. That means that the presence of water absorbs neutrons and slows the reaction. If coolant is lost or is converted to steam, reactor power may increase. This is known as a positive void coefficient and it represents a serious design flaw. Under certain operating conditions, the power can increase uncontrollably until the reactor disintegrates. This is what happened at Chernobyl. No power reactor in the U.S. or Japan can be licensed for construction or operation if it possesses this feature. The graphite blocks are also flammable at high temperatures. A number of Soviet citizens died in the process of putting out the fire caused by the explosion. In addition to the shielding, LWR’s have an even thicker wall of steel- reinforced concrete surrounding the reactor structure. This structure, called a containment vessel, prevents radioactive release in the event of an accident. Because of this feature, no member of the public was injured or killed when the reactor core melted at Three Mile Island in 1979. The Soviet RBMK does not possess a containment vessel. In addition to these fundamental differences in design, U.S. reactors are operated under strict regulations. Unlike what happened at Chernobyl, U.S. and Japanese reactor operators are unable to disable the safety systems which prevent dangerous situations from developing. Although equipment can malfunction, and operators can make errors, the design of U.S. and Japanese light-water reactors prevent these mishaps from leading to dangerous and extreme releases of radiation. What is arguably the most significant difference between what was the Soviet nuclear industry and that of the U.S. is the culture of safety that exists here. Every analysis performed, every decision that is made, and every action taken is done so in the context of the safety of the plant, its personnel, and the local community. Contrary to what many people may believe, this safety culture does not reduce the profitability of the electric utility. Ask any plant manager and he or she will tell you that a safe plant is an efficient plant. Equipment failure or operator mistakes can cost the utility millions of dollars in revenue in addition to regulatory fines. More importantly, however, is the fact that plant employees and their families are members of the local community and have a personal interest in the economic and safe operation of the plant. The Japanese nuclear safety agency has rated the damage at the nuclear power plant at Fukushima at a FOUR on a scale of one to seven, which is not nearly as bad as the Three Mile Island accident in the United States in 1979, which registered a FIVE. The International Atomic Energy Agency — an inter-governmental organization for scientific co-operation in the nuclear field — said it uses the scale to communicate to the public in a consistent way the safety significance of nuclear and radiological events. The International Nuclear and Radiological Event Scale, or INES, ranges from one to seven with the most serious being a seven referred to as a “major accident”, while a one is an “anomaly”. The scale is designed so the severity of an event is about ten times greater for each increase in level. The Chernobyl explosion in the Ukraine in 1986, the worst nuclear power accident ever, was rated a SEVEN. That was the only event classified as a major accident in nuclear power history, exploded due to an uncontrolled power surge that damaged the reactor core, releasing a radioactive cloud that blanketed Europe. The Three Mile Island accident in Pennsylvania was actually a partial core meltdown in which the metal cladding surrounding the fuel rods started to melt. That metal surrounds the ceramic uranium fuel pellets, which hold most of the radiation and power the reactor. Nuclear reactors operate at between 550 and 600 degrees F (between 288 and 316 degrees C). The metal on the fuel rods will not melt until temperatures are well above 1000 degrees F. The ceramic uranium pellets themselves won’t melt until about 2000 degrees. About half the reactor core at Three Mile Island melted before operators restored enough cooling water to stop the meltdown. The core holds the uranium fuel rods, which must be cooled by water to prevent overheating. So how many people died due to the partial core meltdown at Three Mild Island? ZERO. The Sky is falling! The sky is falling! March 14th, 2011 at 2:14 am prisonplanet.com