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Yet another new battery breakthrough

R

Robert Latest

Jan 1, 1970
0
G

Glen Walpert

Jan 1, 1970
0
No useful data also. This thing smells like a fabrication.

The terms in the article are also fishy. Nuclear reactors do not use
control rods for anything other than emergency shutdown. Certainly
not to "initiate" the chain reaction, whatever that means.

Where did you come up with that idea, a Tom Clancy novel perhaps? If
the control rods in a conventional power reactor are not used for
adjusting criticality above unity to ramp up power levels, how do you
think they do it? How do you think they adjust criticality below
unity to ramp down power levels during a normal shutdown, if not with
the control rods?

Try "Elements of Nuclear Reactor Engineering" by L Wang Lau, Tennessee
Valley Authority, for an explanation of how control rods work.
 
D

default

Jan 1, 1970
0
Indeed. Sounds pricey and will be controversial despite the design.

--Damon

There's a price tag in there. 200kw X 40 years X $.05 = three point
five million dollars? Plus the cost of distribution and investor
profit and they should be able to supply power for about $ 0.12/KWH .
.. .

Toshiba was supposed to be bidding on a small reactor in Gelena Alaska
that was supposed to produce 10 megawatts of power at a cost of 5-12
cents a KWH - TO OPERATE . . . isn't automatic

Different system with a liquid sodium and underground bunker, and
fairly large building.

http://en.wikipedia.org/wiki/Toshiba_4S
 
J

John Larkin

Jan 1, 1970
0
No useful data also. This thing smells like a fabrication.

It does.
The terms in the article are also fishy. Nuclear reactors do not use
control rods for anything other than emergency shutdown. Certainly
not to "initiate" the chain reaction, whatever that means.

They use control rods for control, constantly.

And a reactor can be designed to be under-moderated, where
neutron-slowing (but not neutron absorbing) control rods or equivalent
cooling fluid enhance the reaction rate. A boiling-water reactor is
moderated by the water itself, so if ever the water is lost the main
fission reaction stops. (A moderator is necessary to slow down
neutrons to thermal velocities. Fast neutrons zip through and are
lost.)

One of the problems in the Chernobyl disaster was that the ends of the
absorbing rods acted as moderators, so actually made things worse.

John
 
J

John Larkin

Jan 1, 1970
0
Martin said:

"The [...] reactor is engineered to be fail-safe and
totally automatic and will not overheat."

Hey, that's great! A safe nuclear reactor at last. Also note the welcome
change in marketing language, quite different from the "Prone to failure by
human error--non-negligible risk of contaminating large populated arteas"
that we got so used to.

robert

How could that reactor be safe? It would have a critical mass of
uranium, and produce the standard cocktail of incredibly nasty hot
isotopes. And it would kill any person or cat who hung out in the
vicinity for very long. At least you wouldn't need to mow the grass
nearby. Hey, store the apartment complex's garbage next to the
reactor, so it will stay fresh and odorless.

John
 
J

Jim Thompson

Jan 1, 1970
0
Martin said:

"The [...] reactor is engineered to be fail-safe and
totally automatic and will not overheat."

Hey, that's great! A safe nuclear reactor at last. Also note the welcome
change in marketing language, quite different from the "Prone to failure by
human error--non-negligible risk of contaminating large populated arteas"
that we got so used to.

robert

How could that reactor be safe? It would have a critical mass of
uranium, and produce the standard cocktail of incredibly nasty hot
isotopes. And it would kill any person or cat who hung out in the
vicinity for very long. At least you wouldn't need to mow the grass
nearby. Hey, store the apartment complex's garbage next to the
reactor, so it will stay fresh and odorless.

John

Sounds like something everyone in San Francisco should have... along
with their overly taxed caffeinated soft drinks ;-)

...Jim Thompson
 
J

Jim Yanik

Jan 1, 1970
0
Martin said:

"The [...] reactor is engineered to be fail-safe and
totally automatic and will not overheat."

Hey, that's great! A safe nuclear reactor at last. Also note the
welcome change in marketing language, quite different from the "Prone
to failure by human error--non-negligible risk of contaminating large
populated arteas" that we got so used to.

robert

How could that reactor be safe? It would have a critical mass of
uranium, and produce the standard cocktail of incredibly nasty hot
isotopes. And it would kill any person or cat who hung out in the
vicinity for very long. At least you wouldn't need to mow the grass
nearby. Hey, store the apartment complex's garbage next to the
reactor, so it will stay fresh and odorless.

John

http://en.wikipedia.org/wiki/Pebble_bed_reactor
 
R

Richard Henry

Jan 1, 1970
0
Martin Griffith wrote:
"The [...] reactor is engineered to be fail-safe and
totally automatic and will not overheat."
Hey, that's great! A safe nuclear reactor at last. Also note the welcome
change in marketing language, quite different from the "Prone to failure by
human error--non-negligible risk of contaminating large populated arteas"
that we got so used to.

How could that reactor be safe? It would have a critical mass of
uranium, and produce the standard cocktail of incredibly nasty hot
isotopes. And it would kill any person or cat who hung out in the
vicinity for very long. At least you wouldn't need to mow the grass
nearby. Hey, store the apartment complex's garbage next to the
reactor, so it will stay fresh and odorless.

Clueless.
 
R

Richard Henry

Jan 1, 1970
0
Sub-megawatt systems are just what we need, especially since our
national power grids are so pathetic or not even existing in enough
places.

What country do you live in?
 
M

Martin Brown

Jan 1, 1970
0
Martin Griffith wrote:
"The [...] reactor is engineered to be fail-safe and
totally automatic and will not overheat."

Supplying it with enough pure Li6 would in itself be excruciatingly
expensive. It sounds more like a research reactor design intended to
produce thermal neutron beams for experimental physics and a bit of
electricity on the side rather than the new must have geek toy.

I expect it was formally launched on 1st April too. No mention of it
at all on Toshibas own Japanese nuclear engineering site and they are
genuine nuclear reactor builders with about 34% of the Japanese
installed base,
Designs which are intrinsically failsafe are now possible.

They are principally selling their new ABWR designs at present for
which 1GW is their idea of a small design. Features list in English
version includes "entranced (sic) reliability". I rather like that
one....

http://www.toshiba.co.jp/nuclearenergy/english/business/reactor/features.htm
How could that reactor be safe? It would have a critical mass of
uranium, and produce the standard cocktail of incredibly nasty hot
isotopes. And it would kill any person or cat who hung out in the
vicinity for very long. At least you wouldn't need to mow the grass
nearby. Hey, store the apartment complex's garbage next to the
reactor, so it will stay fresh and odorless.

Put enough shielding around it and prayer. In about equal measure.

Regards,
Martin Brown
 
J

John Larkin

Jan 1, 1970
0
Martin Griffith wrote:

http://www.nextenergynews.com/news1/next-energy-news-toshiba-micro-nuclear-12.17b.html

"The [...] reactor is engineered to be fail-safe and
totally automatic and will not overheat."

Hey, that's great! A safe nuclear reactor at last. Also note the welcome
change in marketing language, quite different from the "Prone to failure by
human error--non-negligible risk of contaminating large populated arteas"
that we got so used to.

robert

How could that reactor be safe? It would have a critical mass of
uranium, and produce the standard cocktail of incredibly nasty hot
isotopes. And it would kill any person or cat who hung out in the
vicinity for very long. At least you wouldn't need to mow the grass
nearby. Hey, store the apartment complex's garbage next to the
reactor, so it will stay fresh and odorless.

John

Sounds like something everyone in San Francisco should have... along
with their overly taxed caffeinated soft drinks ;-)

...Jim Thompson


We have a lot of rooftop solar here, which makes about as much sense.

John
 
J

Jeff Liebermann

Jan 1, 1970
0
Where did you come up with that idea, a Tom Clancy novel perhaps?

I like Tom Clancy military books because they inspire the imagination.
If
the control rods in a conventional power reactor are not used for
adjusting criticality above unity to ramp up power levels, how do you
think they do it? How do you think they adjust criticality below
unity to ramp down power levels during a normal shutdown, if not with
the control rods?

Correct. Todays reactors use control rods for shutdown, not for fine
turning and regulating power levels. They certainly are not used to
"initiate" the reaction, which the article suggests. Frankly, I don't
see how one could safely build even a tiny reactor without control
rods, as the article also suggests.
Try "Elements of Nuclear Reactor Engineering" by L Wang Lau, Tennessee
Valley Authority, for an explanation of how control rods work.

Ah, the voice of authority. See:
DOE FUNDAMENTALS HANDBOOK. NUCLEAR PHYSICS AND REACTOR THEORY
<http://www.hss.energy.gov/NuclearSafety/techstds/standard/hdbk1019/h1019v1.pdf>
<http://www.hss.energy.gov/NuclearSafety/techstds/standard/hdbk1019/h1019v2.pdf>
section on Control Rods and section on Soluable Poisons in volume 2.

See:
<http://en.wikipedia.org/wiki/Control_rod>
which offers:

Additional means of reactivity regulation

Usually there are also other means of controlling reactivity:
In the PWR design a soluble neutron absorber (boric acid) is added
to the reactor coolant allowing the complete extraction of the
control rods during stationary power operation ensuring an even
power and flux distribution over the entire core. This chemical
shim, along with the use of burnable neutron poisons within the
fuel pellets, is used to assist regulation of the long term
reactivity of the core,[5] while the control rods are used for
rapid changes to the reactor power (e.g. shutdown and start up).
Operators of BWRs use the coolant flow through the core to control
reactivity by varying the speed of the reactor recirculation pumps
(an increase in coolant flow through the core improves the removal
of steam bubbles, thus increasing the density of the
coolant/moderator with the result of increasing power).

In other words, the control rods are used for emergency shut down,
while a soluable nuclear poison (chemical shim) is used for power
control in pressurized water reactors. Control is by changing the
concentration of boron in the cooling water, which is rather a slow
process more suitable for control, not for an emergency shutdown.
(Despite the lack of speed, some SCRAM procedures dump nuclear poisons
into the cooling water for additional safety.) A chemical shim is
also useful for long term compensation for nuclear poison buildup and
fuel depletion. Since the proposed Toshiba reactor has an alleged
lifetime of 40 years, presumeably without replenishing the fuel, such
long term fine compensation will be a necessity.
 
J

Jeff Liebermann

Jan 1, 1970
0
A strange meaning for "get rid of".

Ye of little imagination. Let's make the assumption that you wanted
to design a radioactive decay assisted domestic water heater for the
purpose of disposing of hot reactor byproducts and waste. Three
obvious problems appear immediately.
1. Pollutants in the water may be become radioactive.
2. Shielding is necessary to avoid exposure.
3. Heat build up must be regulated and controlled.

The first (hot dirt) can be solved by filtration. Considering the
junk found in domestic water, this might be a good idea even without
nuclear heating. Incidentally, nuclear heated water will be
essentially sterilized.

Shielding can best be accomplished by burying the water heater. This
is the method that Toshiba proposes for their domestic reactor. It's
also a common paradigm, where anything dangerous is made safe by
burying it. Polyethylene foam should work well for both shielding and
thermal insulation. The water in the heater will also provide
substantial shielding.

Heat build up is a big problem. Unlike with a chain reaction, there
is no easy way to regulate nuclear decay. It will decay, and
therefore generate heat, continuously and without much variation. Left
to itself, the water will simply get hotter and hotter, until it boils
away. Some method of removing the waste heat will be necessary and
can be done with conventional thermodynamic methods such as radiators
and heat pumps.

There are plenty of other technical problems that will need to be
solved. I'm sure they can be dealt with as they appear.

If the US embarks on a program to bury moderate half-life reactor and
fuel processing byproducts in domestic water heaters, there will
surely be a substantial reduction in domestic energy requirements,
nuclear waste disposal, and water borne pathogen problems. We have
successfully deployed fundamentally dangerous substances, such as
propane, natural gas, and fuel oil, gasoline, electric power, etc in
the home. We can surely do the same with nuclear power. After all,
it is energy and should not go to waste.
 
J

Jan Panteltje

Jan 1, 1970
0
If the US embarks on a program to bury moderate half-life reactor and
fuel processing byproducts in domestic water heaters, there will
surely be a substantial reduction in domestic energy requirements,
nuclear waste disposal, and water borne pathogen problems. We have
successfully deployed fundamentally dangerous substances, such as
propane, natural gas, and fuel oil, gasoline, electric power, etc in
the home. We can surely do the same with nuclear power. After all,
it is energy and should not go to waste.

It would work, but the risk of Osama & Co ordering one,
taking it apart, and making a dirty bomb, is too big.
 
R

Richard Henry

Jan 1, 1970
0
Ye of little imagination. Let's make the assumption that you wanted
to design a radioactive decay assisted domestic water heater for the
purpose of disposing of hot reactor byproducts and waste. Three
obvious problems appear immediately.
1. Pollutants in the water may be become radioactive.
2. Shielding is necessary to avoid exposure.
3. Heat build up must be regulated and controlled.

The first (hot dirt) can be solved by filtration. Considering the
junk found in domestic water, this might be a good idea even without
nuclear heating. Incidentally, nuclear heated water will be
essentially sterilized.

Shielding can best be accomplished by burying the water heater. This
is the method that Toshiba proposes for their domestic reactor. It's
also a common paradigm, where anything dangerous is made safe by
burying it. Polyethylene foam should work well for both shielding and
thermal insulation. The water in the heater will also provide
substantial shielding.

Heat build up is a big problem. Unlike with a chain reaction, there
is no easy way to regulate nuclear decay. It will decay, and
therefore generate heat, continuously and without much variation. Left
to itself, the water will simply get hotter and hotter, until it boils
away. Some method of removing the waste heat will be necessary and
can be done with conventional thermodynamic methods such as radiators
and heat pumps.

There are plenty of other technical problems that will need to be
solved. I'm sure they can be dealt with as they appear.

If the US embarks on a program to bury moderate half-life reactor and
fuel processing byproducts in domestic water heaters, there will
surely be a substantial reduction in domestic energy requirements,
nuclear waste disposal, and water borne pathogen problems. We have
successfully deployed fundamentally dangerous substances, such as
propane, natural gas, and fuel oil, gasoline, electric power, etc in
the home. We can surely do the same with nuclear power. After all,
it is energy and should not go to waste.

I proposed in a letter to the local utility some years ago that they
dispose of their radioactive waste by delivering small quantities of
it to all their stockholders.
 
M

Martin Griffith

Jan 1, 1970
0
It would work, but the risk of Osama & Co ordering one,
taking it apart, and making a dirty bomb, is too big.

That would solve the decommissioning problem, would'nt it?



martin
 
G

Glen Walpert

Jan 1, 1970
0
I like Tom Clancy military books because they inspire the imagination.

Some are entertaining, but facts are not his big strong point. I only
mentioned him because I read some serious reactor misinformation in
one of his books, similar to your apparent misconceptions.
Correct. Todays reactors use control rods for shutdown, not for fine
turning and regulating power levels. They certainly are not used to
"initiate" the reaction, which the article suggests.

OK, then tell us how they start the reaction, if not with the control
rods.

(I agree that they are not used to trim full power level in some
reactor designs, but disagree that this is even slightly similar to
"not used for control" or "only used for emergency shutdown".)
Frankly, I don't
see how one could safely build even a tiny reactor without control
rods, as the article also suggests.


Ah, the voice of authority. See:
DOE FUNDAMENTALS HANDBOOK. NUCLEAR PHYSICS AND REACTOR THEORY
<http://www.hss.energy.gov/NuclearSafety/techstds/standard/hdbk1019/h1019v1.pdf>
<http://www.hss.energy.gov/NuclearSafety/techstds/standard/hdbk1019/h1019v2.pdf>
section on Control Rods and section on Soluable Poisons in volume 2.

I did, but it provides absolutely no support for your stated position.

These documents are management overviews of basic reactor theory,
completely lacking in detail. The reactor engineering textbook I
mentioned gets into the actual design methodology in much more detail,
being written for engineers not managers.
See:
<http://en.wikipedia.org/wiki/Control_rod>
which offers:

Additional means of reactivity regulation

Usually there are also other means of controlling reactivity:

But the control rods are still the primary means of control.
In the PWR design a soluble neutron absorber (boric acid) is added
to the reactor coolant allowing the complete extraction of the
control rods during stationary power operation ensuring an even
power and flux distribution over the entire core. This chemical
shim, along with the use of burnable neutron poisons within the
fuel pellets, is used to assist regulation of the long term
reactivity of the core,[5] while the control rods are used for
rapid changes to the reactor power (e.g. shutdown and start up).

--------------------------------------------^^^^^^^^^^^^^^^^^^^^^

Which part of "shutdown and startup" do you not consider to be
control?
Operators of BWRs use the coolant flow through the core to control
reactivity by varying the speed of the reactor recirculation pumps
(an increase in coolant flow through the core improves the removal
of steam bubbles, thus increasing the density of the
coolant/moderator with the result of increasing power).

Indeed, control rod position is not the only means of adjusting
criticality. Just the only one that has fast response, and the only
one used for *normal* startup and shutdown in the current generation
of PWRs and BWRs. Fine shimming of full power with other means in
some reactor designs does not make the function of the *control* rods
something other than control.
In other words, the control rods are used for emergency shut down,

and normal shutdown, and normal startup, and normal large adjustments
in power level if any - all control except for slow fine adjustment of
full power levels in some reactor designs. Most definitely not *only*
used for emergency shutdown.
 
R

Richard the Dreaded Libertarian

Jan 1, 1970
0
@e23g2000prf.googlegroups.com>, [email protected] says...
Yeah, the big agri-industry pushed MBTE on us, now they're pushing
ethanol. Too much corn if you ask me.

Wasn't it the greenies and their anti-lead crusade that gave us
MTBE?

Thanks,
Rich
 
R

Rich Grise

Jan 1, 1970
0
[email protected] wrote in
no security,no protection against vehicles or aircraft crashing into
it(intentionally or accidentally),no containment dome.

Why not email Toshiba and ask them about these things?

Good Luck!
Rich
 
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