I can hardly believe this... (US environmental policy)

No offense but seriously, i get the feeling this radical insanity only happens in America. Almost like Creationists voting on universe or creation facts. Using vote objection when a simple fact is that the Planet needs to be kept clean in order for people to live in it or animals or anything.

I can say i sincerely agree with Aristotel about democracy.
 
I have a little bit of difficulty following your argument. If you are stating that TMI could not have been as bad as Chernobyl even if the worst had happened, then I agree with you.

I am an electrical engineer, not a nuclear engineer, but I can answer your question about the difference between the two reactor types: due to the fundamental differences in design, a Chernobyl style incident is not possible in US LWR reactors. I'm not talking magnitude of release or level of destruction, although I don't believe our reactor design makes that likely. Let me be clear - it is literally impossible for the same disaster to occur.

Chernobyl housed five RBMK reactors, of which four were active. Soviet designed reactors did not, and to the best of my knowledge still don't, use a containment vessel around their cores. They also use graphite rods instead of water to moderate the intensity of fission. Since water absorbs neutrons, loss of coolant water means the reactor runs hotter and faster. This is a great design if you want to produce a lot of plutonium for weaponization. Not so much for safe commercial nuclear power.

TMI, like all US civilian reactors, is a Light Water Reactor (LWR). We use water as our moderator. No water, no fission. Water also doesn't catch fire like graphite. Also, all US civilian reactors are required to provide a full reinforced containment vessel around their core. It is a different design specification entirely.

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The cause of the Chernobyl disaster as I understand it is that the operators elected to shut off the emergency coolant circuit while testing the turbines connected to the #4 core. Apparently, they wanted to spin up the turbines, shut down the turbine generator, and then see if inertia would be sufficient to drive the coolant pumps in the event of an emergency shut down. They dropped power levels too low on the reactor, and the pile became unstable. In order to regain stability, they elected to pull most of the control rods to speed up fission instead of shutting down. When they killed the turbine generator, it reduced power to the pumps as it spun down. As coolant flow slowed, the water vaporized and the fission reaction sped up. The emergency coolant circuit was bypassed, so no water flowed into the system to absorb the excess fission. When the operators realized the magnitude of the nightmare, they tried to scram the reactor by dropping all of the control rods. It didn't work. The fuel rods exploded, also igniting the graphite moderators. Boom! Chernobyl.

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I will not argue with you about the heroism of those who sought to contain the devastation of the Chernobyl incident. They were truly as heroic as the human species can aspire to.
 
LinkPain said:
No offense but seriously, i get the feeling this radical insanity only happens in America. Almost like Creationists voting on universe or creation facts. Using vote objection when a simple fact is that the Planet needs to be kept clean in order for people to live in it or animals or anything.

I can say i sincerely agree with Aristotel about democracy.

You're right dictatorships are a much more efficient form of government. How's that worked out for people in your neck of the woods in the past? :roll:
 
JohnnyEgo said:
I have a little bit of difficulty following your argument. If you are stating that TMI could not have been as bad as Chernobyl even if the worst had happened, then I agree with you.
Somewhat. The question I have is if the accident in Mile island was actually the worse that could happen. Or if it could have been even worse if the engineers did nothing for example. Like a full leak of the reactor to the enviroment for example but I guess that would have required some explosion of huge size. Not exactly the same but similar like in Chernobyle where well much of the issue happend because the roof went sky high and exposed everything to the enviroment and air. I have a hard time to explain what I mean exactly because I dont know all the techical terms in english (though I do understand it German).

And thank you for explain that all to some euro-tard like me :)
 
Crni Vuk said:
JohnnyEgo said:
I have a little bit of difficulty following your argument. If you are stating that TMI could not have been as bad as Chernobyl even if the worst had happened, then I agree with you.
Somewhat. The question I have is if the accident in Mile island was actually the worse that could happen.

Crni - three mile island was our worst disaster ever and nobody got hurt. It's also outdated technology.

If we ever get to build a new facility, it won't be based on that design, so what's your point?

Johnnyego has pointed out some excellent facts that prove we have the capability to build and maintain safe plants and we have a very good storage facility we can't use thanks to politics.

He also supported my position that Obama is not pro-nuclear energy and nothing is going to happen. Until we get a real president willing to change things - we aren't going to build any new plants.

You might as well be discussing the safety factor of fairydust energy plants.
 
DammitBoy said:
Crni - three mile island was our worst disaster ever and nobody got hurt. It's also outdated technology.
BOOOOOOOOOOOOOOOOOOOAAAAAHHHHH :shock:

NO shit Sherlock. I understand that part very well.

I knew that my lack in english would make that question difficult to understand ... but I will try it again.

What I mean is. Did the engineers in Miles PREVENTED something worse. Or was there a potential/risk for some biger accident like some huge explosion. No clue how to explain it else : /

I mean like if they would have done the wrong things not realizing it was a melt down at some point or something liket hat.

I am not even comparing it to Chernobyle right now or with new reactors today. I just want to know if Miles could have been worse.

Like the Cubacrisis which had the potential to end in "world war 3" but someone decided to do the right thing and NOT attack the missile bases or invade Cuba. But it could have been easily worse. If someone preshed the wrong button thinking the Soviets would not react.
 
I believe I understand what you are asking. An LWR reactor core is designed to SCRAM automatically in the event of a serious transient or melt down. What this means is that all the control rods drop, dampening the reaction and reducing heat. Supposedly, the emergency coolant kicks in at this point, although that didn't happen at TMI. Essentially, the fuel rods continue to generate heat, which generates pressure.

With enough heat, the fuel rods and associated assemblies could melt, hit the much cooler water at the base of the pressure vessel, and cause it to either explode within the containment vessel, or launch the pressure vessel like a missile through the side of the containment vessel.

Then you would have high levels of radioactive contamination in the environment. It is unlikely that you would get the same magnitude of ejection of radioactive particles in the atmosphere like we got with Chernobyl, but it would not be pretty.

It should be noted that the above event pretty much assumes that all redundant safety features fail, the core overheats rapidly, and perfect circumstances align to create the steam explosion. It then assumes that the resulting explosion could not be contained by the containment vessel. In other words, it is incredibly unlikely, as TMI proved with a partial meltdown and a disabled emergency cooling system.

I don't think you are retarded in the least. I only know this stuff because I had years of training and experience in nuclear power and electrical engineering, and I have plenty of technical material to refer to when I don't understand something. It is also my habit, whenever possible, to not post on things I am not certain about.
 
Another fun piece of trivia, though it may be apocryphal. When I was a squid (slang for a member of the Navy), we were taught that "SCRAM" originally stood for 'Super Critical Reactor Axe Man'. In the early days of nuclear reactor research, if things started going sideways and the control rods failed to drop automatically, a guy with an axe would go in and cut the rope that held them, using gravity to drop them into the pile. Bad day for that guy.
 
well if you find that "interesting" you might read or already even know about the fate of the K-19 nuclear submarine and the incident of the 4 July 1961.

No clue how correct Wiki is to the situation. But it is interesting

[spoiler:a22d260d38]On 4 July 1961, under the command of Captain First Rank Nikolai Vladimirovich Zateyev, K-19 was conducting exercises in the North Atlantic close to Southern Greenland when it developed a major leak in its reactor coolant system, causing the water pressure in the aft reactor to drop to zero and causing failure of the coolant pumps. A separate accident had disabled the long-range radio system, so they could not contact Moscow. The reactor temperature rose uncontrollably, reaching 800 °C (1,470 °F) — almost the melting point of the fuel rods — and the chain reactions continued despite the control rods being inserted via a SCRAM mechanism. The reactor continued to heat up as coolant is still required during shutdown until the reactions decrease. Despite Zateyev's and others' earlier requests, no backup cooling system had been installed.

As a cooling back-up system had not been installed, Zateyev made a drastic decision; a team of seven engineering officers and crew worked for extended periods in high-radiation areas to implement a new coolant system by cutting off an air vent valve and welding a water-supplying pipe into it. Since the ship carried chemical suits, instead of radiation suits, they were certain to be lethally contaminated,[citation needed] but the repair team was unaware of the degree of risk, believing the suits they wore would protect them from contamination. The released radioactive steam, containing fission products, was drawn into the ventilation system and spread to other sections of the ship. The cooling water pumped from the reactor section worked well.

The incident contaminated the crew, parts of the ship, and some of the ballistic missiles carried on board; the entire crew received substantial doses of radiation, and all seven men in the repair crew died of radiation exposure within a week, and twenty more within the next few years. The captain decided to head south to meet diesel submarines expected to be there, instead of continuing on the mission's planned route. Worries about a potential crew mutiny prompted Zateyev to have all small arms thrown overboard except for five pistols distributed to his most trusted officers. A diesel submarine, S-270, picked up K-19's low-power distress transmissions and joined up with it.

American warships nearby had also heard the transmission and offered to help, a rare event during the Cold War, but Zateyev, afraid of giving away Soviet military secrets to the West, refused and sailed to meet the S-270. Its crew was evacuated, and the boat was towed to the home base; after landing, the vessel contaminated a zone within 700 m (2,300 ft). The damaged reactors were removed and replaced, a process which took two years. During this time, there was further radiation poisoning of the environment and the workers involved.

The official explanation of the disaster is that during the repair process, it was discovered that the catastrophe had been caused by a drop from a welding electrode that had fallen into the first cooling circuit of the aft reactor during the initial construction. However, this is disputed. According to retired Rear-Admiral Nikolai Mormul, when the reactor was first started ashore, no pressure gauge had been connected to the first cooling circuit. By the time somebody realized what was happening, the pipes had been subjected to a pressure of 400 atmospheres; double the acceptable limit. Checking the pipes would have been costly and reporting the negligence would have hurt the career of Captain Zateyev, who preferred to hide the fact. K-19 returned to the fleet, now having acquired the additional nickname "Hiroshima".

On 1 February 2006, former President of the Soviet Union Mikhail Gorbachev proposed in a letter to the Norwegian Nobel Committee that the crew of K-19 be nominated for a Nobel Peace Prize for their actions on 4 July 1961.[3] In late March 2006, Nikolai Zateyev was formally nominated for the award.[/spoiler:a22d260d38]

Anyway. Thank you a lot for your explanation. Very appreciated.

*Anyway today I am very likely going to train with a physicist I know quite well and he has a lot of litreature regarding nuclear weapons and I guess he has quite some knowledge about nuclear technology in general. It will be interesting to hear his oppinion about Russian - US reactors. And how likely a Chernobyle would have been with western designs. At that time at least.
 
Crni Vuk said:
well if you find that "interesting" you might read or already even know about the fate of the K-19 nuclear submarine and the incident of the 4 July 1961.

Didn't we already cover that the soviets sucked at nuclear energy?
 
Since the theme is now nuclear power.

"A state of emergency was declared at the Fukushima power plant after the cooling system failed in one of its reactors when it shut down automatically because of the earthquake.

The local government urged 2,000 nearby residents to evacuate the area as a precaution. Prime Minister Naoto Kan said no radiation leaks at that power plant or any of the other reactors in the quake-hit zone had been detected."

Now..how big earthquakes are american reactors made to stand?
 
Loxley said:
Now..how big earthquakes are american reactors made to stand?

It varies based on site history and maximum probable magnitude. Very few of our civilian reactors are located on or near active fault lines. Most of the central US reactors are built to a standard of somewhere around 7.7-8.0 Richter based on a safety margin above the historical magnitude of the 1812 New Madrid quakes. Without having specific knowledge, I imagine our West Coast reactors are built to a higher spec. I do know we dismantled at least one reactor in California that stood atop an active fault line in the 70s.

Japan faces a lot more seismic exposure, and their reactors are built reflective of this peril. Though they have not faced an earthquake of this magnitude before, several reactors have been exposed to 7-7.6 magnitude earthquakes with considerable ground energy, and have withstood the shaking with little or no damage of any kind.
 
It would have to be a hell of a fire. Keep in mind that the pressure vessel itself is designed to contain the tremendous heat of the nuclear reaction, and the containment vessel is designed to mitigate radioactive release in the event of an explosion. The bigger concern would be a loss of coolant flow from the supporting facility, which is why standard practice is to shut down the reactor in events such as this.
 
On an unrelated note, this is a wind energy plant installed, at least metaphorically, in my back yard.

hg36a.jpg


hg53c.jpg


Wind energy is very viable in the southwest and high plains as a supplement to the numerous NG plants that provide 80% or more of the electricity in this area.

Environmentalists are of two minds on this 'clean, renewable energy source'. Mostly the complaints center on bird kills and disturbing the natural landscape and sound scape. Some folks are just never happy.

I think they are kind of pretty.
 
There are some near a friend's house in Gaspesia , and so long as they aren't completely clustered, I see no reason not to have them, as you said they are not ugly, hell they don't even make much noise. Oh, and I read that it was actually bats that got slaughtered by the machines because it distrupted their senses or something.

Still, small communities resent having them, and protests abound. Until the companies double the compensations, that is, then it's always OK.
 
Well, that Trailer looked very Fallout-y at least in the scenery, too bad its an MMO, I am not fan of MMO's
 
Mostly people argue about what kind of powerplant is the best/safest/cleanest kind. The need for big powerplants could be reduced significantly if we would use wasted energy (mainly heat) efficiently. By using heat-power-coupling on individual buildings heating-system, the wasted heat is transformed into electrical power and either used to support the house itself or fed back into the grid. Estimates are between 30 and 50% of saving on electrical power. Mind you, this depends hugely on the kind of predominant heating-system in a country, the kind of insulation of the buildings and the distribution of the energy grid. As an added bonus the power production is decentralized and not as vulnerable to acci-dents, sabotages and whatnot.

The only problem (political or financial, not technical) is to upgrade all the current heatings with WKK.

Also of course there is the same approach to energy as to money: if you cant get more, spend less.
 
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