The AP1000 is a very good design by all accounts. China is going full bore with these things but they bought hardware and the technology. The emergency cooling is sort of a self licking ice cream cone.
I don't know how many reactors the Japanese are going to lose but it's at least two so far. Both are old but still, that's a lot of money to waste on a concrete land mark. I just read that they will be venting to the atmosphere for a considerable period of time. Possibly as long as a year - which seems a bit overstated - but people are going to be unable to go home until the mess is buttoned up. This is going to be an ongoing saga.
The Bank of Japan dumped more than eighty billion dollars into the Japanese economy this morning. That's real money.
One of the workers at the local Nuke plant would set off the radiation detector that they scan everyone with when they enter the plant. Come to find out he took a vacation in Europe and brought back some food products that he was consuming. The products had enough radiation to set off the alarms.
Not grass, it's usually called sagebrush or wormwood. I have some planted in my front yard for the wonderful, rural smell. I think it's A. ludoviciana rather than vulgaris.
-- You create your opportunities by asking for them. -- Patty Hansen
Even while thousands of people are reported dead or missing, whole neighborhoods lie in ruins, and gas and oil fires rage out of control, press coverage of the Japanese earthquake has quickly settled on the troubles at two nuclear reactors as the center of the catastrophe.
Rep. Ed Markey (D., Mass.), a longtime opponent of nuclear power, has warned of "another Chernobyl" and predicted "the same thing could happen here." In response, he has called for an immediate suspension of licensing procedures for the Westinghouse AP1000, a "Generation III" reactor that has been laboring through design review at the Nuclear Regulatory Commission for seven years.
Before we respond with such panic, though, it would be useful to review exactly what is happening in Japan and what we have to fear from it.
The core of a nuclear reactor operates at about 550 degrees Fahrenheit, well below the temperature of a coal furnace and only slightly hotter than a kitchen oven. If anything unusual occurs, the control rods immediately drop, shutting off the nuclear reaction. You can't have a "runaway reactor," nor can a reactor explode like a nuclear bomb. A commercial reactor is to a bomb what Vaseline is to napalm. Although both are made from petroleum jelly, only one of them has potentially explosive material.
Once the reactor has shut down, there remains "decay heat" from traces of other radioactive isotopes. This can take more than a week to cool down, and the rods must be continually bathed in cooling waters to keep them from overheating.
On all Generation II reactors?the ones currently in operation?the cooling water is circulated by electric pumps. The new Generation III reactors such as the AP1000 have a simplified "passive" cooling system where the water circulates by natural convection with no pumping required.
If the pumps are knocked out in a Generation II reactor?as they were at Fukushima Daiichi by the tsunami?the water in the cooling system can overheat and evaporate. The resulting steam increases internal pressure that must be vented. There was a small release of radioactive steam at Three Mile Island in 1979, and there have also been a few releases at Fukushima Daiichi. These produce radiation at about the level of one dental X-ray in the immediate vicinity and quickly dissipate.
If the coolant continues to evaporate, the water level can fall below the level of the fuel rods, exposing them. This will cause a meltdown, meaning the fuel rods melt to the bottom of the steel pressure vessel.
Early speculation was that in a case like this the fuel might continue melting right through the steel and perhaps even through the concrete containment structure?the so-called China syndrome, where the fuel would melt all the way to China. But Three Mile Island proved this doesn't happen. The melted fuel rods simply aren't hot enough to melt steel or concrete.
The decay heat must still be absorbed, however, and as a last-ditch effort the emergency core cooling system can be activated to flood the entire containment structure with water. This will do considerable damage to the reactor but will prevent any further steam releases. The Japanese have now reportedly done this using seawater in at least two of the troubled reactors. These reactors will never be restarted.
None of this amounts to "another Chernobyl." The Chernobyl reactor had two crucial design flaws. First, it used graphite (carbon) instead of water to "moderate" the neutrons, which makes possible the nuclear reaction. The graphite caught fire in April 1986 and burned for four days. Water does not catch fire.
Second, Chernobyl had no containment structure. When the graphite caught fire, it spouted a plume of radioactive smoke that spread across the globe. A containment structure would have both smothered the fire and contained the radioactivity.
If a meltdown does occur in Japan, it will be a disaster for the Tokyo Electric Power Company but not for the general public. Whatever steam releases occur will have a negligible impact. Researchers have spent 30 years trying to find health effects from the steam releases at Three Mile Island and have come up with nothing. With all the death, devastation and disease now threatening tens of thousands in Japan, it is trivializing and almost obscene to spend so much time worrying about damage to a nuclear reactor.
What the Japanese earthquake has proved is that even the oldest containment structures can withstand the impact of one of the largest earthquakes in recorded history. The problem has been with the electrical pumps required to operate the cooling system. It would be tragic if the result of the Japanese accident were to prevent development of Generation III reactors, which eliminate this design flaw.
Mr. Tucker is author of "Terrestrial Energy: How Nuclear Power Will Lead the Green Revolution and End America's Energy Odyssey" (Bartleby Press,
Cheap, abundant energy HAS to be the bane of every liberal. With cheap, clean power, all social problems go away and liberals exist to exploit victimhood and without victims, liberals go away.
My bad! I redid this laptop and haven't filled the loony bin yet. I had forgotten how vitriolic and vulgar they are. What attracts these trolls to rcm? They know nothing about the subjects. And, why do people respond to them?
Scary, but read up on naturally radioactive places and find that their incidences of cancer are lower than the rest of society's. I guess that living with a higher than normal rad count beefs up your immune system.
Speaking of alarms, my BS alarm went off and I was astounded to read in my newspaper a few years ago about a local guy in Medford, OR who set off a fire truck's radiation alarm as he passed by the truck in his car. They chased him down (while the police caught up to them) and he told them he had just had nuclear chemo at the local hospital. Them rad monitor thangs be SENSITIVE! No wonder they tell you to stay away from your partner and all kids for a week after nuke chemo.
-- Small opportunities are often the beginning of great enterprises. -- Demosthenes
Larry, radiation has effects that are specific to where it is applied. It is one thing to get a dose X from backgroud radiation, spread over the entire body. It it quite another thing to get the same dose from radioactive iodine, localized in a one ounce organ like thyroid.
I knew that. My comment was more regarding the Europeans than Japan. I should have specified. And I know that people visiting high-rad areas aren't as safe eating those foods as those who were born there.
-- Small opportunities are often the beginning of great enterprises. -- Demosthenes
Can you see the huge contradiction in your statement? If opponents to nuclear are the ones in control Why would they need to blow anything up that would just weaken their position
Fact is the opponents to nuclear have practically zero political clout The only reason more nuclear plants are not being built is because investors think the risks outweigh the rewards
Hmmm, I skipped over the third dead horse beating about magog in a book. How did you get to blackended crater? That's what it looked like. Strange, like Gilgamesh era comet, wormwood, Amarah Crater. Did the designers or powers that be name it knowing eventually it would melt down and look like a crater? The comet would look fuzzy like the plant also. And it is north of Is it real.
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They should just build the power plants in a vertical hard rock mine and just bury it in concrete when it expires.
Since when do FACTS matter to the anti-nuke, anti-wind, anti-oil drilling, anti-gun bunch...
Much better to come out screaming and get those sound bites about the doom and gloom and determine what happened from a couple pictures instead of actually asking about what actually happened. Note just how many anti-nuke people on this group jumped up and started saying "see what did WE tell you, look how bad those nukes are" Instead of actually READING and listening to the facts about what is happening and what is likely to occur, you have people screaming "MELTDOWN, MELTDOWN the world is going to end." "It's going to be a Chernobyl sized disaster." Of course these same people only real education about nuclear power comes from the TV or "news stories".
I have quite a few friend in the industry, one of whom was one of the designers on the AP1000. A few more are high level operations and containment designers. For the most part they are ALL saying that there has NOT been enough information given yet for people who are not actually on site to determine the level of damage.
No they just place the areas where the material is off limits or declare it a national reserve and lock it away. They also like to make the regulatory system so difficult that there is no way to get through it.
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