Gurke? Nein Danke...

While Angela Merkel was busy contemplating whether to close down nuclear power, 10 people died from EHEC infected cucumbers. During the same time, nuclear power in the world - including Fukushima - killed noone.

So... if nuclear power is so dangerous that it has actually not killed or seriously injured anyone and therefore needs to be banned... while German cucumbers make people bleed their intestines out to the point of actually dying... doesn't that mean...

 

Gurke? Nein Danke
Gurke? Nein Danke (clickable for high-res image)

Also, as a little side note... in the 80 days that has passed since the Japanese Earthquake and tsunami disaster struck... approximately 400 to 600 people have already been sentenced to premature deaths due to Germany's decision to close down nuclear power, from the increased emissions from fossil fuels. Now Germany plans to add another 10 000 MW of coal power to its production to replace the nuclear power, meaning another 100 000 to 250 000 people will die, due to the extra pollution this will cause.

Way to go Angela...

Day 68: Video of work at Fukushima and a encouraging PDF

TEPCO has released a video that shows work being done at the Fukushima plant. Very interesting to watch.

One gets a real sense for the devastation the tsunami inflicted while watching that clip.

TEPCO also recently released this PDF file that gives an overview of work being done. I will add some pictures from it:

In the above picture one can see how they plan to rig up the new heat exchangers for reactor 1. Within the reactor building, but outside the containment, they will put a water to water heat exchanger. They will pump water from within the containment through this heat exchanger, where it transfers the heat to a secondary circuit that in turn flows to a heat exchanger outside of the reactor building that dumps the heat to the air. This is the original plan TEPCO had before they realized the full extend of the damage to the number 1 core and containment, so it is not sure they will progress as described. But the secondary heat exchanger and its piping is already being built.

Tepco also shows the above picture on how they plan to reuse leaking water from the containment as cooling for the reactor. It is not clear how the two plans are connected to each other. I would assume the second plan is the one that is going to be used instead of the first plan. Instead of taking water directly out of the containment they will use the existing leakage paths, purify the water and pump it back into the reactor.

For the number 2 reactor shown above the main problem is to stop the leakage from the suppression pool. They plan to excavate the reactor building in order to access the room where the suppression pool is housed and then fill the entire volume with grout. Considering that (probably) the suppression pool is leaking at number one as well then maby this plan will be implemented there as well (just my speculation).

Both in unit 2 and 3 are they planning to reuse the leaking water in the same manner as in unit 1.

In the rest of the document they give some basic information on how they plan to clean the massive amounts of contaminated water that exists on the site, some details on the protective building they want to build around the reactors and how to prevent more contamination of soil, water etc. Well worth scrolling through, massive work is certainly ongoing at the site and it seems TEPCO has a solid plan that they are implementing.  Of course more surprises will without a doubt pop up during work, but it looks promising. We are still waiting for more in depth information on the situation of the number 2 and 3 reactors.

English blogs:
All Things Nuclear TEPCO Says Core of Unit 1 Melted
Atomic Power Review Fukushima Daiichi update, Weds. morning 5/18

English News:
New York Times Venting Failure in the Nuclear Reactors at Fukushima Daiichi
Reuters UK nuclear power gets green light

/Johan

 

Day 67: Complete meltdown of the number 1 core

During the last days a lot of news has been released by TEPCO. TEPCO has released this presentation that gives more details of the events that took place in the number 1 reactor from the beginning of the earthquake up until now. To summarize the content of the presentation.

  • The water level gauge has been giving wrong readings, the reading has been stating that the water level is about 1.7 meters below the top of the fuel assemblies. In reality the water level has been 8 meters below the top of the fuel assemblies, this means the entire length of the fuel has been uncovered completely.
  • TEPCO now assumes the RCIC system failed after the tsunami (another news release indicates it was manually shut down!!)
  • 16 hours after the earthquake the entire core had suffered a meltdown and all of it dropped down to the lower part of the pressure vessel.
  • The temperature readings on the vessel indicate that the core is still mostly within the vessel and adequately cooled.
  • Some parts of the core is suspected to have melted small holes in the bottom of the containment, which explains why they could not increase water level despite increasing pump rate.

They don't mention the reading of the pressure gauge that indicates the vessel pressure is about 14 atmospheres. I was personally fooled by this reading and assumed the number 1 vessel is in better shape than the number 2 and 3 reactors. The question is what readings can be trusted at all.

Due to this new information on the status of the reactor TEPCO has decided to scrap the original plan to flood the containment up to the level of the fuel assemblies. Since all the fuel is now located at the bottom of the vessel there is no need to flood the containment that high.  The containment is also confirmed to be breached and water leaking out of the it like in the case with reactor number 2.

Another theory for the explosion in the number 4 reactor building has appeared. The videos from the pool show that it is largely intact and no major fuel damage can be seen. That means it seems unlikely hydrogen from a zircalloy+water reaction in the spent fuel pool can be the cause of the explosion. Instead TEPCO now believes hydrogen leaked into the number 4 building from a shared ventilation system with the number 3 reactor.

TEPCO is going to do more complete analysis of the status of reactor 2 and 3 and the information will be released within days. It will be interesting to see if the RCIC system (see this blog post for a description of the system) worked in the other 2 reactors and, if it did, to what extent it mitigated the consequences of the station blackout.

Work is progressing on all fronts to build a enclosure around the number 1 reactor, to build a water processing plant, create more redundancy in the electricity supply, clear the area of debris and to pump away the junk water from the turbine halls and trenches. IAEA as usual reports the release of radioactive material and dose rates.

The Fukushima accident has unfortunately seen its first death with a 60 year old worker that lost consciousness  while working on a drainage system to the radioactive waste storage. He was brought to a hospital but could not be revived. So far there is no report that the death was related to radiation.

 

News English:
WNN Fukushima fuel melt confirmed
WNN Theory for Fukushima Daiichi 4 explosion
WNN Revisions to Fukushima restoration roadmap

Blogs English:
Depleted Cranium Worker Dies at Fukushima Nuclear Plant
Atomic Power Review Core totally demolished at Fukushima Daiichi No. 1

Blogs Swedish:
TEM funderingar <Är kärnkraft förnybart?
Den blinde Argus Kärnkraft och rädsla
Supermiljöbloggen IPCC: Förnybart kan ersätta fossila bränslen
Fourfact Blinkar jätten?
Skattepolitik och samhällsfilosofi Inga elbilar i Sverige om Tyskland stänger kärnkraften?
Ann-Kristine Johansson Kärnkraftsdiskussion
Nina Drakfors Japan, kärnkraftshaveriet fortsätter och kräver strålningsdödstal
Supermiljöbloggen Amerikansk kärnkraft dåligt rustad för katastrofer

/Johan

Day 58: Dose rates climbing in the number 2 wetwell

Another week has passed and more steps have been taken to get the situation under control. Lets start with the usual reactor status table  made out of NISA data:


Reactor 1 Reactor 2 Reactor 3
Water level (meter)* -1.7 -2.1 -2.15
Flow rate(m3/min) 8 7 9
Core pressure (kPa) 1390 - -
Containment pressure (kPa) 120 60 102
Wetwell pressure (kPa) 110 - 183.2
Feedwater nozzle temp (Celsius) 119.8 115.6 202.1
Bottom head temp (Celsius) 96.9 - 151.9
Wetwell temperature (Celsius) 51.4 66.8 40.0
Containment dose rate (Sv/hour) - 22.7 12.2
Wetwell dose rate (Sv/hour) 1.1 148 0.480
*Distance from top of assembly
- broken gauges or missing data

Everything looks pretty stable except the wetwell dose rater in the number 2 reactor. It has increased to well over 100 Sv/hour from 37.1 in the last update I made (i wrongly wrote 0.371).  I haven't been able to follow the news so closely the last week so I have not seen if this has been mentioned in any TEPCO press release. Below is a graph of the increase. If anyone know of any action done on the number 2 reactor, starting the 3 or 4th of may please write a comment to this blog post.



 

A air filtration system has been connected to the reactor building of reactor number 1. The purpose of it is to get airflow through the building and clean out the air activity by filtrating the air. It is hoped that it will be enough to allow workers to enter the building and work safely without getting to much dose.

Kyodo reports that TEPCO plans to send in workers on monday in order to measure dose rates within the building. Seems strange that they would send in people when they have already used robots once for that purpose.

A longer video clip of the number 4 spent fuel pool can be seen over at Atomic Power Review. It doesn't appear to be very damaged.

The big news of the week is that the prime minister of Japan has asked Chubu electric to shut down its Hamaoka nuclear power plant. Hamaoka has 3 operational nuclear power plants, all of them quite new. Started at 1987, 1993 and 2004. The newest one is a ABWR and would presumably have state of the art eartquake protection. The reason for the prime ministers request is a estimate that the site  has a high probability to be hit by a 8.0 earthquake within 30 years. If the reactors indeed can not handle such a quake then the closure request is rational. But it does smell a bit like political posturing at this point. There is no legal precedence for such a situation and it is not clear if Chubu electric has to obey the request.

 

 

Links(English)
WNN Filters for Fukushima Daiichi 1

Blogs(English)
Atomic Power Review Japan updates: Fukushima Daiichi, Hamaoka
NEI NEI Weekly Update on Fukushima Daiichi – 5/6/1

Blogs(Swedish)
Effekt Monbiot brottas med sig själv
Genusnytt En KARL ska väl tåla lite strålning...
Forskarbloggen Hur många döda efter Tjernobyl?
inas insikter Tjernobyl idag / Fukushima imorgon?
Begrundat och Plitat Cesium och Jod verkar ge spikes i Fukushima när man gläntar på dörren ...

/Johan

Why I do not trust "We don't need nuclear" rethorics

Dear Mr./Ms. Anti-Nuclear Activist... for decades You have been telling me "It's easy to get off nuclear, if we just want to!". Well, alot more powerful people than You have made similar promises...

Where do we stand today after all these promises? Pretty much exactly where we were 5-10-20-40 years ago.

So - dear Mr./Ms. Anti-Nuclear Activist - You promise me gold and green forests... but You don't deliver. Maybe this wasn't Your fault. Maybe You'd like to blame Big Oil or lazy politicians or a public that just won't see things the way You do. It's allright... You can try to shift the blame any place You want. But it doesn't matter whose fault it is, becasue assigning blame does not alleviate the problem.

So when You - dear Mr./Ms. Anti-Nuclear Activist - today, yet again, try to tell me it's allright to renounce nuclear power, it means I cannot trust You, because things might no go they way You promise me they will.

What will You - dear Mr./Ms. Anti-Nuclear Activist - need to do to gain my trust again?

Well it's easy: get the replacements up and running. Get full replacements for fossil fuels and nuclear power up and running, hooked to the grids and pumping GigaWatthours of energy into them, and I'll trust You again.

So... dear Mr./Ms. Anti-Nuclear Activist.... get to work. We're eagerly waiting for You.

Oh... and one last thing: while we wait for you to get this work done, You do not get to say we cannot make any new nuclear power if we want to, at least on the "We're not gonna need it in a while"-argument alone.  Just saying this FYI...