
Cringley: Japan may have just permanently lost 20% of its electricity supply - tomfakes
http://www.cringely.com/2011/03/flea-powder-may-be-saving-lives-in-japan/?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed:+ICringely+(I,+Cringely)
======
neutronicus
Like they wouldn't have boron near a nuclear reactor. I'm a PWR man myself,
but I am 99% sure that GE BWR designs have a couple of big tanks of borated
water specifically for a LOCA. I highly doubt they're having reactivity
problems, it's probably just managing the decay heat, and now the radiation
leaks, that's the problem. "Just" is a relative word, here, of course.

 _Boiling water reactors are simpler, cheaper, but generally aren’t made
anymore because they are perceived as being less safe. That’s because the
exotic coolant in the pressurized water reactor can contain boric acid which
absorbs neutrons and can help (or totally) control the nuclear reaction. You
can’t use boric acid or any other soluble boron-laced neutron absorbers in a
boiling water reactor because doing so would contaminate both the cooling
system and the environment._

He's completely wrong about industry adoption of BWRs. There are two BWR's
planned to be built in the US (along with 3 or 4 PWRs), and I believe that
China has contracted with GE for a few as well (along with 4 Westinghouse PWRs
and maybe a few Areva ones too).

PWRs are preferred largely because of their higher power densities (a BWR core
that produces the same power must be larger) and simpler nuclear calculations
and control strategies (two-phase flow makes calculations much more difficult,
and it's harder to calculate correct positions for control blades (whose
effects are highly localized) than it is to calculate the correct boron
concentration (whose effects are smeared over the whole core)). However, now
that computers are faster and us nuclear engineers no longer have the excuse
of slow computers to hide behind, PWRs are looking to move away from relying
on Boron concentration as the main form of control (the Westinghouse AP1000,
specifically, relies much more on rod movement than the AP600), because of the
cost of performing regular boron dilutions.

He's right that BWRs are simpler and cheaper - about half the moving parts.

~~~
masklinn
> Like they wouldn't have boron near a nuclear reactor.

They probably do, the question is whether they can carry it to the site faster
than the US navy, and whether the boron tanks have not been compromised.

~~~
neutronicus
The question is also, and I didn't make it clear enough in my original post:

"Wait, they need _boron_?"

Boron is a neutron absorber, and is therefore used to control the fission
rate. You add boron when you're afraid of the fission rate getting out of
control (e.g. Chernobyl). This is a legitimate concern here for two reasons:

1) A BWR is significantly more reactive (conducive to a high fission rate) at
cold zero power than at hot full power, because cold water is a better neutron
moderator than steam.

2) Xenon-135 and Samarium-149 are by-products of nuclear fission that have an
effect on reactivity similar to boron. Their half-lives are on the order of
hours, so when you crank down the fission rate, a couple hours later you also
crank down the concentrations of Xe-135 and Sm-149, which, if you're not
careful, can cause the reactor to go supercritical (and possibly prompt
supercritical - a form of criticality in which everything happens
approximately a thousand times faster - pretty much the worst-case reactivity
excursion scenario) again a few hours after shutdown.

So, basically, you need enough negative reactivity from somewhere, either
control rods or borated water, to counteract these two reactivity insertions.
The Japanese reactor is almost certainly designed so that inserting all of the
control rods into the core will kill any and all reactivity increases after
shutdown.

What is most likely occurring is that there is very little nuclear fission
inside the reactor right now. All the power inside the reactor is coming from
decaying fission products, and it's probably on the order of kilowatts, it's
just that the when the flow rate through the core drops from gallons per
second to essentially nothing, a few kilowatts per cubic foot will get you
pretty damn hot pretty damn quick. At this point some of the fuel rods have
probably failed as well (if not melted), so the water in the reactor may be
nastier than usual.

Unless the control rods have failed or are in the process of failing, I doubt
that boron is even necessary for reactivity control, except as insurance. My
educated guess is that their problems are entirely thermal- and containment-
related, and that there is no danger of a reactivity accident, since a xenon
transient or a condensation transient would have run its course by now, so the
control rods probably have enough reactivity worth to keep the reactor
subcritical indefinitely.

~~~
masklinn
They don't want to control reactivity anymore, they likely want to kill the
reactor core completely in order to not take any risks (not just to keep the
core subcritical, but to avoid it simply melting as well, if the pumps did not
work they don't have the waterflow they need, so the next option is to end the
core _fast_ ). And for that, boron is the best tool.

~~~
neutronicus
Subcritical _is_ "killed completely" from a nuclear standpoint - lowering the
reactivity of an already subcritical reactor (e.g. adding neutron absorbers)
does nothing but make the fission rate decrease faster. The fission rate
already changes on short time scales, (e.g. orders of magnitude in
minutes/hours during a scram). If the fission rate is already essentially
zero, which it is in the Japanese reactor by now, it does nothing at all.

The heat inside the core is being produced by the decay of fission products,
and there's absolutely nothing you can do to stop that except wait for enough
half-lives that the activity slows down a bit.

Your general thesis, namely that as soon as they decide the reactor can't be
salvaged, they'll dump in a bunch of boron just to be safe on the nuclear
front, is correct, but where you're wrong is in assuming that adding a bunch
of boron will help cool the reactor at all - it won't. All it will do is
ensure that the reactor never goes critical again.

This is why spent fuel needs to sit in a pool of water for 5 years before
anyone even considers moving it. Decay heat is serious shit, and it's not
related to neutron physics at all.

EDIT: Probably time to get more specific about the term "reactivity".
Reactivity is related to the "multiplication factor", which tells you how much
bigger each generation of neutrons is than the last. It's zero when each
subsequent generation is the same size - this is the normal operating state of
a reactor, positive when each subsequent generation of neutrons is larger, and
negative ... you get the idea.

If you've ever touched population dynamics in a differential equations class,
you'll realize that this is a recipe for exponential growth and decay.
Basically the time scale on which nuclear reactions proceed is "reactivity /
mean neutron lifetime", with the caveat that if your reactivity is _just_
above zero, neutron population growth is constrained by the longest-lived
neutrons (it's like if every family has 2 kids, except for a couple hundredths
of a percent, who have three, but put their third kids in cryostasis for a
thousand years). In practice, this is how reactors are operated, because the
mean neutron lifetime is _very_ small, so the worst thing that can happen is
if your reactivity moves outside of this regime (this happened at Chernobyl).
If your reactivity is negative, you are _always_ constrained by the longest-
lived neutrons, but that's okay, because even this time scale is pretty short.

The upshot here is that if each successive generation of neutrons is smaller
than the last, the number of neutrons (and hence things like fission rate that
depend linearly on the number of neutrons) decays exponentially with a pretty
short time constant.

The definition of "subcritical" is "having negative reactivity", so if the
reactor is subcritical for any length of time, the fission rate will have
exponentially decayed down to a tiny number.

------
lambda
I don't know much about nuclear reactors. To my untrained ear, what Cringely
says sounds fairly reasonable. But then, having read a bunch of articles of
his linked in the past on computer hardware and software, which I do know
something about, I find that what he writes usually falls into one of two
categories: (1) stuff that's obvious to anyone who knows what they're talking
about and are paying any attention at all, and (2) crack-pot half-baked ideas
that are laughable and completely wrong.

He's also lied about having a PhD. I wouldn't consider him a very trustworthy
source. If he's saying something reasonable, someone else more credible has
probably already said it.

~~~
jordanb
He has an article in which he gives an explanation of what happened at TMI in
his own words. Being a nerd for this stuff and having read the report of the
president's commission (which he claims to have been on) I was... shocked to
say the least.

Its hard to imagine he was actually on the same committee as the people who
wrote the report. His explanation had _elements_ that mirrored the report. For
instance, there was a particular warning light discussed in both. But what
function the light served in the plant, its behavior during the crisis, the
operators' response to it, or its overall role in the incident, on these
Crigley was dead wrong.

I suspect he got assigned to the president's commission for political reasons,
or because he was a 'public media personality,' but that he actually
contributed nothing. He remembers an indicator light because he sat there
dumbfounded in the meeting where the smart people on the committee discussed
it. He then incorporated that into his incredibly child-like and incorrect
mental model of what happened.

Suffice to say, regardless of his experience on the TMI president's
commission, his understanding of nuclear power is even more comically
incorrect than his understanding of computers.

------
foobarbazetc
Here's what you need to read instead of Cringley:

[http://en.wikipedia.org/wiki/Boiling_Water_Reactor_Safety_Sy...](http://en.wikipedia.org/wiki/Boiling_Water_Reactor_Safety_Systems)

Combine that with these:

[http://www.tepco.co.jp/en/press/corp-
com/release/11031219-e....](http://www.tepco.co.jp/en/press/corp-
com/release/11031219-e.html)

[http://www.tepco.co.jp/en/press/corp-
com/release/11031220-e....](http://www.tepco.co.jp/en/press/corp-
com/release/11031220-e.html)

And you can see what's going on. Ignore everything else.

------
djcapelis
Uhm... the other units at _Chernobyl_ re-entered service for a solid decade
after that incident. (Only one of them lasted a decade. Unit 2 caught on fire
in '91. Unit 1 was shut down in '96 and Unit 3 lasted until Dec '99.)

Cringley's prediction will be wrong. There are a lot of units at that station,
two of which are ABWR cores. I would speculate that the _majority_ of these
units will return to service.

~~~
TomOfTTB
I think you're right but I give him credit for drawing attention to a big
issue that everyone else is ignoring which is Japan's diminished production
capacity (rather than focusing on the doomsday meltdown scenarios most of the
media are fixated on).

Even if they return to service eventually there's going to be downtime. That's
going to force Japan to use more fossil fuels which will drive up the price
(even more). Add a spike in oil costs to the loss of japanese economic output
and I think our modest economic recovery just hit a big snag.

~~~
MichaelApproved
Oil isn't used to make electricity. The major options are nat gas and coal.

This disaster will likely drive DOWN oil prices since Japan will likely need
less of it in the short term.

~~~
stevefarnworth
I'm sorry? _Oil isn't used to make electricity_

Oil is used in some types of power station, and the markets are already
reacting to not only the increased demand, but due to the infrastructure
damage in the north of the country, the fact it'll be harder than ever to get
it delivered.

<http://online.wsj.com/article/BT-CO-20110312-700945.html>

~~~
MichaelApproved
I initially assumed that Japans energy gneration profile was similar to the US
where it's almost all coal and LNG which is why I didn't think it would impact
the oil market as much.

A bit of googling gave me this article which states that oil is actually more
popular than coal.
[http://www.fepc.or.jp/english/energy_electricity/electric_po...](http://www.fepc.or.jp/english/energy_electricity/electric_power_sources/index.html)

I still wonder if their demand will go up since a lot of the infrastructure is
damaged and unusable. But if it does go up, chances are they'll need more fuel
oil.

------
nathanhammond
One of the interesting things about disaster recovery planning for nuclear
power plants is that you count on (X) number of things to go wrong and figure
out how the plant recovers gracefully. In Japan they've effectively had three
things go wrong: earthquake, tsunami, and general infrastructure damage. Most
disaster scenarios only cover a single event and TEPCO has a lot to deal with.

In a disaster scenario the first reactions are generally passive (dropping of
control rods, changing where water flows) and then "all" that remains is to
cool the decay heat. Aye, here's the rub: the cooling system is not a passive
system. It requires power to drive the water pumps for the cooling system that
siphons the heat away from the reactor vessel. After initiating reactor
shutdown the most critical time period is the first little while as that is
when there is the most heat. Too much heat and it'll damage the fuel, vessel,
and/or the cooling system and can effectively damage the reactor enough so to
prevent it from ever recovering (thus, meltdown).

The questions left to ask are to what degree the cooling systems (primary and
backup) are working, and whether they've been powered consistently. With that
bit of information alone we'd be able to make a pretty accurate estimate as to
the state of the reactors in question. What is scary is that it would be
really simple to say that all of those systems are working as expected and
that there is nothing to worry about. Since that hasn't been said I'm of the
opinion that there is definitely something to worry about.

~~~
gmac
These "three things" boil down to one thing (the earthquake) and its
foreseeable impacts. I certainly hope the disaster planners wouldn't see these
things as independent failures (and assess probabilities accordingly), but
that kind of hubristic "we can calculate the probabilities of all failure
modes" thinking is one of the reasons I'm not a big fan of nuclear.

~~~
abeld
_but that kind of hubristic "we can calculate the probabilities of all failure
modes" thinking is one of the reasons I'm not a big fan of nuclear._

Would you be more comfortable with "we can't estimate the probabilities of all
failure modes"? I am sure that all engineers involved in planning the failure-
handling systems know that those "calculations of probabilities" are only
estimates based on some assumptions.

I think nuclear often gets bad press _because_ you can measure and calculate a
lot of risks to a much higher precision than in other industries. Like "x
amount of radiation released" where x is actually a very small number but the
fact that you can measure it and make an estimate as to how many cancer cases
will be caused by it makes it scary, while people don't care much about the
risks of, say, coal-mining because thats harder to measure/estimate.

~~~
JoeAltmaier
Doesn't seem to extend beyond energy production. For instance, tell people all
about the dangers in chicken mcnuggets, or smoking, or a sedentery lifestyle,
and they don't get very excited at all. Even if you quote statistics.

Certainly they never go as far as voting against chicken farms.

Its got to be the theoretical nature of nuclear power generation that has
something to do with it. Its invisible, unfathomable and secretive, so folks
distrust it?

~~~
blahblahblah
Chicken mcnuggets, tobacco smoke, and sedentery lifestyles are not members of
the set of "things that can cause arable land to become permanently
uninhabitable". Nuclear accidents are in that set and that is why the public
is (rightly) concerned about them.

~~~
pjscott
Nuclear accidents are not members of the set of "things that are at all likely
to actually hurt you or anybody you know". Sedentary lifestyles and tobacco
smoke _are_ in that set, but they lack the novelty and sensationalism that
gives nuclear accidents their cachet.

~~~
Ratfish
I think that people (self included) are generally more accepting of risk if
it's control is within their own hands. Dying of tobacco related illnesses or
obesity is mostly within my own control. Dying because a a nuclear reactor
leak is pretty much 100% out of my control.

~~~
pjscott
Even then, people's estimates of danger are crazy. A nuclear accident is far
less likely to kill you than any number of other things that are outside your
control. A drunk driver running into you, for example, or a natural gas
explosion.

------
davidhollander
> _Hillary isn’t the kind of person to choose the wrong words_

How has no one pointed out there was never any coolant delivered and Hilary
Clinton did in fact misspeak? It renders this article a bit moot.

[http://www.reuters.com/article/2011/03/11/japan-quake-
nuclea...](http://www.reuters.com/article/2011/03/11/japan-quake-nuclear-
coolant-idUSN1125270120110311) "US did NOT deliver coolant to Japan nuclear
reactor"

"Ultimately, however, Japan did not need assistance from the United States but
Clinton did not appear to have been updated before she made her public
remarks."

~~~
fraserharris
...or the Japanese sourced the coolant themselves (which appears to be the
case) and the article is correct.

------
mahmud
I trust Japanese engineering more than Cringley predictions. Let's wait and
see what the engineers do.

BREAKING NEWS: Pressure successfully released from Fukushima No. 1 reactor:
agency - Kyodo

[http://twitter.com/martyn_williams/statuses/4645894316531712...](http://twitter.com/martyn_williams/statuses/46458943165317121)

\-----

Govt says radioactive measurements near plant roughly doubled, confirming
release of gas.

[http://twitter.com/martyn_williams/statuses/4645969566958387...](http://twitter.com/martyn_williams/statuses/46459695669583872)

~~~
ugh
_“I trust Japanese engineering more than Cringley predictions.”_

What does that even mean?

~~~
Groxx
That Cringely is less reliable than Japanese manufactured / designed goods.

~~~
ugh
That doesn’t make any sense.

~~~
Devilboy
Why is that

------
nabilt
However the events unfold I wonder if this will cause more nations to
investigate other reactor technologies like Thorium. The abundance of Thorium
and its inherent safety mechanisms (as a liquid at least) make the technology
very exciting.

Check out the Google Tech Talk <http://www.youtube.com/watch?v=AZR0UKxNPh8>

~~~
gimpf
Hmm. Here in Central Europe this would probably read:

"However the events unfold we can rest reassured that scientists have to
acknowledge that any use of nuclear technology for electrical power generation
is inherently unsafe and therefore irresponsible."

And then we build a new coal power plant.

~~~
ugh
Not even probably. In Germany, opposition parties already (and once again)
demanded of the government to rethink their nuclear strategy. (No new nuclear
power plants are built or planned in Germany but the coalition government
recently extended the runtime of existing nuclear power plants.)

I'm a bit annoyed that the only two options in Germany seem to be to either
shut all nuclear power plants down or to extend the runtime of the already
existing and rather old nuclear power plants. It seems to me that it is
possible to have safer nuclear power but no political party in Germany seems
to be willing to even talk about that.

~~~
VMG
It is worth mentioning that France is still big on nuclear and we will likely
be buying French power from nuclear plants.

------
gonzo
FUKUSHIMA DAIICHI-1 was already scheduled to be shutdown this month.

<http://www.icjt.org/plants/uni/a/uni194a.html>

neutronicus has even more reasons why what Bob says is very likely wrong.

------
JoelUpchurch
I suspect the decision to use sea water to cool the reactor means that they
have decided to write off the plant. It was 40 years old anyway and nearing
the end of it's service life.

~~~
gonzo
the end of its service life was this month!

<http://www.icjt.org/plants/uni/a/uni194a.html>

~~~
Ratfish
Wondered when someone would mention that. Had seen the link to it in the
comments on the Cringely article, posted by a Cringely sceptic. Weird
coincidence that it happen the month it was due to be decommissioned.

------
tectonic
CNN reports explosion at one of the plants.

<http://www.cnn.com/2011/WORLD/asiapcf/03/12/japan.nuclear/>

------
rbanffy
I find it notable that you have mounting pressure that could risk the
integrity of the pressure vessel, yet can't turn a turbine connected to a pump
to drive cool water through heat exchangers... If a reactor self-destructs
unless you can cool it down actively after an _emergency_ shutdown, there must
be some serious design issues there.

After you completely kill the fission, you still have some heat being
generated from the decay of fission byproducts doesn't sound weird that the
device has enough power to self destruct but not enough to cool itself down?

------
erikstarck
The Fukushima plant produces 4.7GW:
<http://en.wikipedia.org/wiki/Fukushima_I_Nuclear_Power_Plant>

The total nuclear production of energy in Japan is 47GW:
<http://en.wikipedia.org/wiki/Nuclear_power_by_country>

Nuclear is 28.9% of Japan's energy source (same Wikipedia-article as above).

It doesn't add up. Where does the number 20% come from? 2% is closer to the
truth.

------
rospaya
<http://en.wikipedia.org/wiki/Robert_X._Cringely>

Robert X. Cringely is the pen name of both technology journalist Mark Stephens
and a string of writers for a column in InfoWorld, the one-time weekly
computer trade newspaper published by IDG.

~~~
rbanffy
I think that, currently, Cringely is just Stephens.

------
stewbrew
let's just hope a loss of power supply is everything they have to worry about.
it seems some caesium already got out.

------
sliverstorm
Can they not simply ship in extra batteries, or are they batteries too large
to be moved?

~~~
ubernostrum
Well. The datacenter across the street from my office has backup batteries
which weigh in at half a ton apiece. Arranged in groups of _eight_.

And I'm betting they're positively puny compared to what you'd want for a
nuclear plant's cooling system, so simply "shipping in" some extras may not be
all that feasible...

~~~
sliverstorm
I'm sure they are large; I was thinking mostly that as 20% of Japan's energy
and a nuclear reactor are on the line, they'd be able to move many tons of
batteries. Also remember, modern cars weight 1.5-2 tons, and are carried in
sets of 8-10 cross-country by truck.

------
light3
I guess the obvious question is whether 80% of electricity supply meets
demand, probably not, how can Japan generate the additional 20% in a hurry?

~~~
pedrocr
Losing a plant means you lose a percentage of your peak capacity but not
necessarily that you won't be able to provide the total amount of energy
demanded by the economy. You could potentially move a portion of the usage to
off-peak hours, starting with some industrial loads for example, moving a few
factory shifts to the night.

------
MichaelApproved
Japan probably won't need that 20% for a while. Their demand just dropped
significantly.

------
bilban
Not wanting to change the topic. But why on earth would you even consider
nuclear power generation when you are in such a geologically unstable area?
Sounds like idiocy to me. Fingers crossed here, could do without another man
made disaster.

~~~
5l
Why is this getting downvoted? It was the first thing that came to my mind
too. Not only is the country prone to earthquakes, but as I understand,
several of their power stations are built right on the east coast.

It's possible to make a building like a skyscraper fairly earthquake proof,
but is it really possible to make things like nuclear power stations
earthquake proof? Assuming the building is made to 'wobble', wouldn't that
wreak havoc on the cooling systems and other gear inside?

~~~
Bud
Yes. It is possible:

<http://www.world-nuclear.org/info/inf18.html>

It's not like they don't think of this stuff ahead of time. This was planned
for.

