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Comment Re:Larger landing area (Score 1) 342 342

They tried parachutes - didin't work. When they did land it in the sea, it tipped over and broke.

They sure would liked to have landed it on land right away, but have a look at what happened on the barge and now think about how likely it is you would get landing permit for an unproven rocket. You see, you won't get it. So the main thing they are doing right now is demonstrating that they can land it accurately and the maneuver is safe for the public.

They also want to land it on the ocean for performance reasons. Flying the rocket back to land takes a lot of fuel you'd rather use to further accelerate the 2nd stage, if you have a heavy payload.

Comment Re:And why not? (Score 3, Informative) 227 227

The Three Gorges Dam isn't primarily a hydroelectric scheme. It's primary purpose is to protect the lower parts of the Jangtze river from flooding, which has regularly affected some 10-20 mio people.

But you could say the same about lignite or other coal strip-mines. Lignite mining in Germany has stripped some 1500km^2 so far and is still ongoing.

Comment Re:It be 12m above sea - max Tsunami: 7m (Score 1) 122 122

1) The point about the design is that power isn't necessary to cool the reactor, but there are at least 3 emergency generators. (Because of their similarities, the ACP1000 has recently been consolidated with the APC1000 design into the "Hualong One" and the exact details aren't yet available in non-chinese documents.)

I fail to see how the coastline of Fujian has any bearing whatsoever on a power plant in Pakistan.

2) It is, in essence, a standard pressurized water reactor with passive peripherials that don't need pumps. All PWRs can passively remove decay heat through natural convection via the steam generators. Those are where the heat ultimately has to be removed from. This used to be done exclusively by power driven pumps, but it can be done through gravity, if you have heat sink above the steam generator level. Which is what you have.

Engineers aren't stupid.

3) The question of hydrogen formation has been addressed at least since 1957 in the Wash-740 report. It is not new. All current designs include catalytic hydrogen recombiners from the start, which can reduce the hydrogen concentration below the point of combustion. (Combustibility is is a function of hydrogen concentration and water steam contentration. Steam will necessarily be released along with the hydrogen and render it inert for the time being, until the steam is condensed. Enough time for the catalyzers to work.) Unfortunately, older designs haven't been equipped with them in all cases, most notably in Japan - depending on local laws.

Furthermore, the containment itself is also cooled passively in at least some of the newer designs (not sure about the Hualong One). But as far as fallout is concerned, it is enough for the containment to remain sealed until the Caesium aerosols have settled within the containment. (The basic process is the same as with fallout outside the containment. But it is faster, because of the confined environment.)

This happens at a rate of 90% every 8-12 hours, if nothing is done. After one or two days, very little is left. If you use containment sprays (which also reduce pressure in the containment), about 20 minutes are sufficient to remove 90% of the remaining aerosols. (Another 20min will remove 99% etc.) That process is the reason why very little Caesium was released from Three Mile Island.

Unlike the small BWR containments, large dry containment can remain sealed for over 24h even if there is no cooling whatever, because of the much larger volume.

Comment Re:It be 12m above sea - max Tsunami: 7m (Score 2) 122 122

Yes, but this initial window is several days long. Typically 3 days, but the actual amount of time is a matter of the concrete design being build. This depends on the rules under which the design is finalized and the safety margins the rules call for.

After that it is only a matter of refilling the water tank of the heat-exchangers (which serves as heat-sink), which you can do with regular fire fighting pumps using water lines installed when the containment gets build. No helicopter stunts will be needed. You can also use whatever water you can get hold of - including sea water. It's just a heat sink outside the containment, the water doesn't get anywhere near the reactor.

Comment Re:It be 12m above sea - max Tsunami: 7m (Score 1) 122 122

Westinghouse has build Pressurized Water Reactors (PWR), including the ones in Three Mile Island (at least for the most part, it's possible they build some experimental BWRs at the beginning). But the Boiling Water Reactors were designed and build by General Electric. http://en.wikipedia.org/wiki/B...

Comment Re:It be 12m above sea - max Tsunami: 7m (Score 2) 122 122

Next time you need antibiotics - you won't get them.
Next time you're in a car accident - you airbag won't inflate, your seatbelts won't be there, your windshild will be made from ordinary glass, your car's chassis will be stiff.
Next time want to eat, you won't get anything, because there's not enough natural fertilizer, there's no way to combat crop pests, there'll be only horses and oxen to pull the plow and you better get fit for threshing the grain.

I could go on.

Comment Re:It be 12m above sea - max Tsunami: 7m (Score 2) 122 122

Be careful, a Japanese tsunami might flood New York!

Tsunamis can be very tall in very specific places, depending on the geometry. Which is something you could have figured out by yourself, because the article is extremely specific "Omoeaneyoshi district of Miyako City, in Iwate Prefecture".

The point where the nuclear power plant will be build is not a place like the Omoeaneyoshi district of Miyako City, in Iwate Prefecture - which is not at all surprising, because such places are rare. And by the way, Pasni is about 350km way from Karachi. Ormara is 250km away. Their geography bears no relationship wih Karachi.

Comment Re:It be 12m above sea - max Tsunami: 7m (Score 5, Informative) 122 122

The nuclear power plants will be ACP1000s. There is half a century of experience between the ACP1000 and the BWR-3/4 used in Fukushima Daiichi. And wouldn't you know it, there have been improvements in the meantime!

http://www.nucnet.org/all-the-...

It's a combined passive and active design, it doesn't need power to cool the reactor or the containment, but it has powered cooling systems in addition to the passive ones. -> NOT FUKUSHIMA.
A backup generator that is above the Tsunami will not be flooded and will not fail because of flooding because it isn't being flooded. -> NOT FUKUSHIMA.
An emergency stop of a nuclear reacto needs cooling or it will melt the core, which is being provided for in a much more adequate fashion than in Fukushima. -> NOT FUKUSHIMA.
The ACP1000 is a pressurized reactor in a large dry containment, that can contain a molten core without overpressurizing the containment. It is not a small "pressure supression" containment that has been known since at least 1966 to be unable to contain a molten core - which is a statement made by none other than the vendor, General Electric. -> NOT FUKUSHIMA.

Comment Re:It be 12m above sea - max Tsunami: 7m (Score 4, Informative) 122 122

There was none. They used the 1960 tsunami in Japan for reference in Fukushima Daiichi (unlike e.g. Onagawa) - which reached a height of 4.5m. This tsunami was caused by the 1960 Chile earthquake on the other side of the planet, across the pacific.

Yes, baseline nuclear safety in Japan was that crappy - most operators went way beyond the baseline, but at least one didn't.

Comment It be 12m above sea - max Tsunami: 7m (Score 5, Informative) 122 122

This must be the most moronic article I've read in a long time.

3/4 of the way down the text it says the only relevant piece of information: "Minhaj said concerns about the effect of a tsunami are also overblown because the new reactors are being built on a rock ledge about 39 feet above sea level."

That's 12m above the sea. The tsunami generated by a mag 9.0 earthquake is expected to be between 0.9m and 7m high - so the plant will have 5m margin ABOVE THE WORST CASE.

Shut up everyone, you've been lied to.

Comment Re:Is wasn't before it was (Score 0) 87 87

Most likely foreign (western) involvement, which is one of the two things you shouldn't do in Chinese politics.

After being dominated by foreign powers for a mere 110 years there is a certain lack of trust within the Chinese government, as soon as there is foreign involvement in its politics. The movie was picked up by foreign media and foreign activist groups - and that's when it fell from grace.

The other thing you shouldn't do in Chinese politics is criticize the government - in the strict sense. That is: it is OK to criticize the politics OF the government, but it's not OK to criticize the government itself. This is a distinction commonly lost to people here and leads to the impression, that the censorship is arbitrary. Well, it is not.

Comment Re:Science does not work like that (Score 0) 329 329

You neglect about 8000 papers of 12000 papers originally involved that were discarded by the authors of this study, because they lacked a pithy statement in the abstract as to whether they agreed or disagreed with the global warming consensus.

The ACTUAL SCIENTIFIC CONTENT of those 12000 papers played no role at all in this crappy piece of cargo cult science, it was all about whether people made certain statements in the abstract or not.

1000 pains = 1 Megahertz

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