Live Thread- Fukushima Reactors

[hc87]

Please post Fukushima reactors stories here.

[hc87]

http://www.nytimes.com/2011/03/17/world/asia/17nuclear.html?_r=1

[Robe]

You mean they’re all still there ???
Shep Smith will be disappointed ...

[mrsmith]

http://thelede.blogs.nytimes.com/2011/03/16/latest-updates-on-japans-nuclear-crisis-and-earthquake-aftermath-3/

Steve Herman
The peak hourly reading today in Fukushima-shi equaled 1/2 a chest X-ray.
23 minutes ago

ReutersBreakingNews
Japan nuclear safety agency: radiation levels outside Daiichi plant spiked about noon but fell back
26 minutes ago.

Steve Herman
According to latest rad data, folks in Fukushima City were exposed to a spike of radiation 500x above the typical background level.
31 minutes ago

[GonzoGOP]

Quick question. An article was posted last night that showed that radioactive decay would continue to produce .5% of the original reactor power for at least ten days after the reactor was shut down. Since that determines the amount of cooling the reactors need it would seem to be important. How many MW of heat did those reactors produce at peak power. And how much heat does it take to break containment. Get those numbers and we don't need speculation, just mathematics to figure out where this is going.

[SE Mom]

http://www.freerepublic.com/focus/f-news/2689114/posts

[CarryaBigStick]

I understand all four reactors are each rated in the 400-500 megawatt output range.

[Constitution Day]

BUMP

[jpsb]

That I have read, and it would be nice if an expert could verify or debunk, is that these type of reactors produce 7% of the production energy (heat) once shutdown. And require 1 ro 3 years of active cooling. Certain hope that is not true, the info comes from wiki so one never knows.

[janetjanet998]

•NEWS ADVISORY: Water injection into ponds at No. 3, No. 4 reactors priority: agency (22:32)
•NEWS ADVISORY: Spent fuel pool at No. 3 reactor heated, emitting steam: nuke agency (22:27)

and there you have it...there is indeed a spent fuel rod pool there at #3 too(was thought all the rods were in 4)..how much damage did that huge exoplsion do to the pool..are the rods still in the correct positions or are they touching each other now is the question

[ecomcon]

Megawatts electical output is not reactor heat, which is what he is looking for. Further, I understand that residual heat is in the 3 percent range for some time. Could be wrong though.

[CarryaBigStick]

http://resources.nei.org/documents/japan/Used_Fuel_Pools_Key_Facts.pdf

[SargeK]

NRC lists the megawatt thermal (MWt) ratings for operating US reactors. Dresden 1 and 2 are GE Mark 1 BWR - apparently similar to the Fukushima Daiichi plant.

They are rated at 2957 MWt. However, I’m not sure this is a useful comparison, since the figure listed is an operating rating - basically an upper limit of the licensed power for the plant.

With a loss of core structural integrity, loss of the geometry, loss of moderator control, I’m not sure we can calculate with any degree of confidence how much heat the plant will produce in its current state, at least not without a lot of data that even the plant operators themselves are struggling to determine.

If it were just a matter of the reactor being scrammed, all rods in place, all systems normal, then yes we could I’m sure reasonably estimate how much decay heat will be produced. Right now, there are just too many wildcards for that sort of computation.

But then, I’m not a nuclear engineer.

[janetjanet998]

The past few hours some in japans goverment have said the radiation is now below the level to cause harm to humans....while at the same time the defense minister said the helo operation to dump water on the reactors was called off becuase of high radiation. so which is it?

[xzins]

Radioactive fallout downwind is scary stuff.

My basic opinion is that I’m glad that I don’t live anywhere near those Fukushma plants at this point in time.

America has enough coal to power itself for 250 years AND convert coal to liquid for powering our cars.

But, we’re not permitted to tap that resource.

[SargeK]

Correction, Dresden 2 and 3.

[globelamp]

Here are the reactors at Fukushima Dai-Ichi:

1 × 460 MW (Unit 1 damaged)
4 × 784 MW (Units 2, 3, and 4 damaged; Unit 5 experiencing cooling problems)
1 × 1,100 MW (Unit 6 experiencing cooling problems)

[CarryaBigStick]

Megawatts output has a direct correlation to heat output of the reactor. Watts can be easily converted to BTU’s. 450,000 watts equals 25613.84 BTU/hours.

[TEXOKIE]

I saw a thread last night about the reactors being in cold shutdown. Could someone look into this and confirm it or at least discuss it?

http://www.freerepublic.com/focus/f-news/2689332/posts

This is the article coaltrain referenced:
http://www.world-nuclear-news.org/IT-All_Fukushima_Daini_units_in_cold_shutdown-1503114.html

From the thread another article is mentioned by B4Ranch:
http://www.iaea.org/newscenter/news/tsunamiupdate01.html

[CarryaBigStick]

Oops, BTU/minutes, not hours.