Peak Oil
Donate Bitcoin

Donate Paypal


PeakOil is You

PeakOil is You

Big Oil warns of coming energy crunch

General discussions of the systemic, societal and civilisational effects of depletion.
Post a reply

Unread postby Dezakin » Sat 06 Aug 2005, 19:15:25

Ludi is posting a link that primarily cites the Storm van bullshit report that was thouroughly dissected as utter garbage a month ago... the one that inflates decomissioning costs, selectively uses the most energy intensitve mining techniques from half a century ago, and most telling, only assumes gasseous diffusion enrichment for light water reactors, something that no one does anymore because its so energy intensive.

And yes, breeder reactors are discounted with one or two sentances as being unviable in spite of decades of experience with them.

I've been over this before with Ludi and shown why nuclear fuel and nuclear power wont run out in any timeframe worth discussing. Uranium and thorium is everywhere.

$this->bbcode_second_pass_quote('', 'I')f the article is correct, then IFR's are the safest, cheapest example of nuclear power to date.


Ah, lets have a sense of perspective here. The IFR was a testbed reactor for doing molten salt reprocessing of metallic fuels. The IFR certainly isn't cheap, less safe than a LWR and presents a significant proliferation risk compared with other reactors, even other breeders. The first problem the IFR faces is the sodium cooling system is a huge mass of chemical potential locked up just waiting to start sodium fires should there be any loss of coolant incident.

Second its a fast neutron reactor that primarily runs on Pu-239, so the delayed neutron component of the reactor (the beta) is very low... meaning the reactivity flux doesn't occur over minutes like in thermal and epithermal reactors but seconds to microseconds. A giant flux is a huge neutron flash incidient waiting to happen and possibly cause corresponding fuel melt.

Interesting work was done at ANL but its a mistake to look at the reactor there as any sort of next generation design. Indeed, all liquid metal breeder reactors are best for doing one thing: make weapons grade Pu239, with some incidental power production at over twice the price of a LWR.
User avatar
Dezakin
Heavy Crude
Heavy Crude
 
Posts: 1569
Joined: Wed 09 Feb 2005, 04:00:00
Top

Unread postby Cyrus » Sat 06 Aug 2005, 19:37:23

$this->bbcode_second_pass_quote('', 'A')nd yes, breeder reactors are discounted with one or two sentances as being unviable in spite of decades of experience with them.


Why do you suppose the superpheonix reactor was discontinued? HMM?
User avatar
Cyrus
Tar Sands
Tar Sands
 
Posts: 647
Joined: Tue 25 Jan 2005, 04:00:00
Top

Unread postby pilferage » Sat 06 Aug 2005, 19:53:39

$this->bbcode_second_pass_quote('Cyrus', '')$this->bbcode_second_pass_quote('', 'A')nd yes, breeder reactors are discounted with one or two sentances as being unviable in spite of decades of experience with them.


Why do you suppose the superpheonix reactor was discontinued? HMM?


Public opinion. I kinda wonder what would happen to the automobile if the safety requirements were as rigorous as nuclear power? ;)
http://en.wikipedia.org/wiki/Superph%C3%A9nix
"Humankind cannot gain anything without first giving something in return. To obtain, something of equal value must be lost. "
User avatar
pilferage
Tar Sands
Tar Sands
 
Posts: 553
Joined: Sun 21 Nov 2004, 04:00:00
Location: ~170ft/lbs@0rpm (on my bike)
Top

Unread postby Dezakin » Sat 06 Aug 2005, 19:53:46

$this->bbcode_second_pass_quote('', 'W')hy do you suppose the superpheonix reactor was discontinued? HMM?


Because its a costly reactor to maintain and France has enough Pu-239 to satisfy its nuclear weapons requirements. If you want to make a breeder reactor for producing electric power, Superfenix would not be it.

In fact, given how extraordinarily cheap uranium is today and likely to be for the next century, I'm not sure any breeder reactor is going to be worth any extra costs. If breeders come out competitive it will be because of benifits besides fuel efficiency; Smaller waste streams perhaps.

But to assume that breeder reactors are unworkable in principle is ignoring the decades of experience with them.
User avatar
Dezakin
Heavy Crude
Heavy Crude
 
Posts: 1569
Joined: Wed 09 Feb 2005, 04:00:00
Top

Unread postby pilferage » Sat 06 Aug 2005, 20:29:58

Since I don't know much about nuclear power, I'll post links to various parts of one of the articles I posted, with the hope that you'll be kind enough to provide insight.

$this->bbcode_second_pass_quote('Dezakin', 'T')he IFR certainly isn't cheap

It would seem to me that the reactor producing the most energy from some given amount of material is the cheapest in terms of the vague EROEI.

$this->bbcode_second_pass_quote('', '[')b]Then I won't worry. How do IFRs help conserve natural resources?

Thermal reactors are incredibly profligate with the earth's endowment of potential nuclear fuel. The once-through, "throw-away" cycle in favor in the U.S. uses less than a hundredth of the energy potential of the mined uranium. Even with recycle, less than 2% can be extracted. IFRs can use over 99%.

Well anyway, with uranium so cheap, why do we care about conservation?

For the same reason we care (or should) about conserving petroleum, even though oil is now cheap. The current world-wide glut of reactor fuel is strictly temporary. Particularly with the U.S. throw-away cycle, the economically available U-235 is not predicted to last much longer than the petroleum reserves - a few decades.


$this->bbcode_second_pass_quote('Dezakin', 'l')ess safe than a LWR


$this->bbcode_second_pass_quote('', '[')b]How safe are IFRs?

While the safety record of commercial reactors of Western design is superb, Three Mile Island notwithstanding, it would be desirable to have reactors that rely more on inherent safety features and less on engineered ones. ALMRs do that.


$this->bbcode_second_pass_quote('Dezakin', 'a')nd presents a significant proliferation risk compared with other reactors, even other breeders.

$this->bbcode_second_pass_quote('', '[')b]But suppose a country wanted to make some bombs, and had nothing but an IFR?

If their IFR plants were safeguarded, the material in the processing stream would be highly undesirable, as I explained earlier, and their chances of diverting it undetected would be slim indeed. If not safeguarded, they could do what they could do with any other reactor - operate it on a special cycle to produce good quality weapons material. But in either case, most likely they would do what everyone else has done: construct a special production facility. Detecting such a clandestine facility is probably the main, immediate challenge facing international safeguards, and has nothing to do with whether a country has IFRs or LWRs.

How does that isotopic argument go?

In outline, like this: Designers of military weapons demand plutonium that is at least 94% Pu-239, although it is technically possible, with difficulty, to make an explosive with plutonium of almost any isotopic composition. Plutonium from LWR spent fuel runs around 60% or less Pu-239, while that from IFRs tends to be in the 70-80% range, and thus is somewhat closer to what weapons designers want.

There must be a downside. What is the single best technical argument against the IFR?

Isotopic composition of the plutonium. This is not at all a forceful argument, but it is probably the only one with any technical validity. (There are arguments, largely nontechnical, about whether the IFR is needed or whether it would be economical.)

Why isn't that a forceful argument?

First, isotopic contamination is only one of many obstacles between a proliferator and a weapon from IFR fuel. I mentioned some of them a while back.

Second, having material that is 80% Pu-239 instead of 60% does not greatly lessen the difficulty of designing and building a bomb.

Third, and most important, remember that there are far easier ways to get fissile material for weapons - high quality material, at that - than from spent reactor fuel. Iraq, for instance, chose uranium enrichment. No country has ever used reactor-grade plutonium to make weapons.


$this->bbcode_second_pass_quote('Dezakin', 'T')he first problem the IFR faces is the sodium cooling system is a huge mass of chemical potential locked up just waiting to start sodium fires should there be any loss of coolant incident.

Don't the "inherent safety features" override other problems like this, in terms of the overall risk?

$this->bbcode_second_pass_quote('', '[')b]But doesn't sodium burn in air and react violently with water?

Yes it does, and this of course requires prudent design, involving inert atmospheres and multiple barriers.

$this->bbcode_second_pass_quote('Dezakin', 'S')econd its a fast neutron reactor that primarily runs on Pu-239, so the delayed neutron component of the reactor (the beta) is very low... meaning the reactivity flux doesn't occur over minutes like in thermal and epithermal reactors but seconds to microseconds. A giant flux is a huge neutron flash incidient waiting to happen and possibly cause corresponding fuel melt.

First off, can we moniter and head off a huge flux? And if it does occur, would the "fuel melt" result in something similar to this?

$this->bbcode_second_pass_quote('', '[')b]Wasn't passive cooling tested in a prototype ALMR?

Yes, it was. All control power for the operating reactor was cut off. Coolant pumps stopped, control rods did not move, and the operators did nothing. The core temperature rose slightly, causing the reactor to go subcritical and shut itself down without incident. Unassisted convective cooling then prevented overheating.

$this->bbcode_second_pass_quote('Dezakin', 'i')ncidental power production at over twice the price of a LWR.

Now is this assuming the current stable price of fissable material? Or during the long run (lets say 10k years), are IFR's still more expensive than LWR's even though they make much better use of the energy potential of fissable materials and result in material that doesn't need to be stored as long?

$this->bbcode_second_pass_quote('', '[')b]Are there other waste-disposal problems that could be lessened?

Yes. Some constituents of the waste from thermal reactors remain appreciably radioactive for thousands of years, leading to 10,000-year stability criteria for disposal sites. Waste disposal would be simpler if that time frame could be shortened. With IFR waste, the time of concern is less than 500 years.
"Humankind cannot gain anything without first giving something in return. To obtain, something of equal value must be lost. "
User avatar
pilferage
Tar Sands
Tar Sands
 
Posts: 553
Joined: Sun 21 Nov 2004, 04:00:00
Location: ~170ft/lbs@0rpm (on my bike)
Top

Unread postby Ludi » Sat 06 Aug 2005, 21:47:51

$this->bbcode_second_pass_quote('Dezakin', '
')
I've been over this before with Ludi and shown why nuclear fuel and nuclear power wont run out in any timeframe worth discussing. Uranium and thorium is everywhere.


I consider nukes unsustainable because they produce long lasting toxic waste. It's totally irrelevant to me whether we have infinite years of uranium and thorium supplies, that does not in itself make the technology sustainable.
Ludi
 
Top

Unread postby AmericanEmpire » Sun 07 Aug 2005, 00:36:11

There's just no way we can continue this way of life into the future anymore. The massive energy consumption way of life is over, period.
AmericanEmpire
Coal
Coal
 
Posts: 452
Joined: Thu 14 Jul 2005, 03:00:00
Top

Unread postby Dezakin » Sun 07 Aug 2005, 00:51:07

pilferage:
$this->bbcode_second_pass_quote('', 'I')t would seem to me that the reactor producing the most energy from some given amount of material is the cheapest in terms of the vague EROEI.


Well, breeder reactors in general sure are going to be more energy efficient than light water reactors. But the world runs on money efficient, which is related only obliquely to energy efficiency.

Of breeder reactors, sodium cooled metal fueld reactors are decidedly an inferior choice except for rapidly building up weapons material. For this purpose, IFR like facilities would be ideal save for the reprocessing regime.

$this->bbcode_second_pass_quote('', 'W')ell anyway, with uranium so cheap, why do we care about conservation?

For the same reason we care (or should) about conserving petroleum, even though oil is now cheap. The current world-wide glut of reactor fuel is strictly temporary. Particularly with the U.S. throw-away cycle, the economically available U-235 is not predicted to last much longer than the petroleum reserves - a few decades.


This argument is misleading. Spent fuel doesnt just become useless after its finished in a light water reactor. You can chemically extract all the neutron poisons and fission products and burn the fertile and fissile fuel it in a variety of reactors. And if we only used the once through fuel cycle with our global power requirements, we might only have tens of thousands of years of fuel rather than hundreds of millions. It really isn't worth talking about conservation alone when discussing breeders because of fuel avaliability. Theres just too much of it.

$this->bbcode_second_pass_quote('', 'W')hile the safety record of commercial reactors of Western design is superb, Three Mile Island notwithstanding, it would be desirable to have reactors that rely more on inherent safety features and less on engineered ones. ALMRs do that.


This statement is misleading also. ALMR's might have some inherent saftey features that arent present in LWR's currently in use, but there are significant risks in fast neutron reactors that this little faq ignores entirely: very high prompt neutron ratios, positive void coefficients, sodium fires, and other issues are among the risks just not present in LWR's (or superior breeders such as molten salt breeder reactors)

$this->bbcode_second_pass_quote('', 'B')ut suppose a country wanted to make some bombs, and had nothing but an IFR?


Then they'd be able to do it much faster than if they had a LWR of the same power output. Liquid metal cooled reactors were designed for this sort of thing in mind.

$this->bbcode_second_pass_quote('', 'H')ow does that isotopic argument go?
One of the real reasons that weapons designers prefer 94%+ Pu239 in the isotopic mix is because of the lack of spontaneous fissions. It makes it easy and safe to handle and very predictable so you can make very calculated designs ideal for fusion triggers.

But spontaneous fissions from isotopically dirty reactor grade Pu just means that a country/organization running on the cheap doesnt have to put together a neutron trigger.

$this->bbcode_second_pass_quote('', 'N')o country has ever used reactor-grade plutonium to make weapons.

Uh, not true. Britain did, harvested from magnox reactors. North Korea claimed to.

$this->bbcode_second_pass_quote('', 'D')on't the "inherent safety features" override other problems like this, in terms of the overall risk?

Remind me what inherent safety features there are besides a higher than average negative temperature coefficient. There are reactors with inherant saftey features that prevent meltdowns and other accidents, but they aren't the IFR design.

$this->bbcode_second_pass_quote('', 'F')irst off, can we moniter and head off a huge flux? And if it does occur, would the "fuel melt" result in something similar to this?

Yes we can monitor this and mitigate it, in light water reactors. With fast reactors life just sucks... the prompt neutron ratio is so high that you might only have microseconds to scram the reactor rather than minutes. Now unless you engineer your plant to turn into a bomb, this isn't the end of the world, but a giant neutron flash criticality excursion is a bit dangerous and can damage the reactor.

And yes, this can cause the fuel to melt. The heat has to go somewhere.

$this->bbcode_second_pass_quote('', 'N')ow is this assuming the current stable price of fissable material? Or during the long run (lets say 10k years), are IFR's still more expensive than LWR's even though they make much better use of the energy potential of fissable materials and result in material that doesn't need to be stored as long?

Given that you can run LWR's on MOX fuel and how insensitive nuclear power is to fuel price, LWR's will probably still outperform IFR in 10k years, but that speculation holds technology standing still and pretends other reactors dont exist. IFR sucks not just because its a bad design compared to LWRs in the economics, saftey, and proliferation departments, but also because it compares poorly to other breeder reactor designs... certainly the molten-salt breeder reactor is far superior, as is the Pb-Bi metal cooled fast reactor, the pebble bed fast reactor, and so on.

I like the idea of doing on site reprocessing, I really do. I just think the MSBR does it much much better. True negative void coefficients, much higher delayed neutron ratio, no fuel fabrication, most strongly negative temperature reactivity, low vapor pressure, high efficiency. I'm not sure if uranium will ever be expensive enough to start building a bunch of them though.

Ludi:$this->bbcode_second_pass_quote('', 'I') consider nukes unsustainable because they produce long lasting toxic waste. It's totally irrelevant to me whether we have infinite years of uranium and thorium supplies, that does not in itself make the technology sustainable.
Sorry I mischaracterized your position, but the report you cited was attacking nuclear power on a lack of fuel. I would argue that the waste stream eventually becomes harmless as it decays and that the relative amount of waste compared to any other industry is very small, but I suspect not small enough for your sensibilities.
User avatar
Dezakin
Heavy Crude
Heavy Crude
 
Posts: 1569
Joined: Wed 09 Feb 2005, 04:00:00
Top

Unread postby eric_b » Sun 07 Aug 2005, 04:43:56

Oh no. Not this old argument again.

I agree with deza, that at least technically, nuke power plants can provide all the
power we need for centuries, if not much longer. Economically I'm not as certain.

And I also feel the entire nuclear waste problem is waaay overblown. The stuff can
be dealt with. Yucca mountain is a start. Consider that your average coal fired power
plant emits pounds and pounds of radioactive elements everyday through its smokestack,
which fall out as a residue in the environment and end up in the food chain. During the
early days of nuclear testing the US (and other countries) disposed of tons
of nuclear waste by simply putting it in barrels and dumping these in the Ocean.
Sometimes the barrels were shot full of bullet holes to encourage them to sink. Nuke
waste is bad, but most of its reputation is hysteria.

Nuke power is really the only option we have if we want to continue an 'energy dense'
way of life.

That said, I'm with the people in the powerdown camp. It's the only sane solution.
(which is why it will never happen.) Ideally all power would be derived
from wind and solar, and the human population would be much less than it
currently is.

All the above just underscores that we are f*cked at this point.

Good day.
User avatar
eric_b
Heavy Crude
Heavy Crude
 
Posts: 1174
Joined: Fri 14 Jan 2005, 04:00:00
Location: us
Top

Unread postby shakespear1 » Sun 07 Aug 2005, 05:36:03

Have you guys heard of this design which has many advantages as has been run by the Germans ( Laboratory ) for 21 years? Pebble Bed

$this->bbcode_second_pass_quote('', 'C')hina, along with South Africa, is currently at the forefront in the development of so-called pebble bed reactor technology, which could offer substantial reductions in both risk of meltdown and volume of radioactive waste.

A pebble bed reactor in Julich, Germany, ran successfully for 21 years, from 1966 to 1988, before opposition to nuclear power forced its decommissioning in the aftermath of the 1986 Chernobyl disaster.
Men argue, nature acts !
Voltaire

"...In the absence of the gold standard, there is no way to protect savings from confiscation through inflation."

Alan Greenspan
shakespear1
Heavy Crude
Heavy Crude
 
Posts: 1532
Joined: Fri 13 May 2005, 03:00:00
Top

Unread postby Ludi » Sun 07 Aug 2005, 08:44:24

$this->bbcode_second_pass_quote('Dezakin', '
')Sorry I mischaracterized your position, but the report you cited was attacking nuclear power on a lack of fuel. I would argue that the waste stream eventually becomes harmless as it decays and that the relative amount of waste compared to any other industry is very small, but I suspect not small enough for your sensibilities.


Actually the article has a section devoted to environmental reasons why nukes aren't sustainable.
Ludi
 
Top

Unread postby LateGreatPlanetEarth » Sun 07 Aug 2005, 18:03:56

USA will have to go balls out on Nuclear and Wind to prudently use what fossil fuels are left; transportation will bear the blunt. This along will be enough to sink the economy; probably around 2010, we'll go into a recession and when it starts to rebound likes it has for the last 1/2 century, this time it will not be unable to. Thus, the stair stepping to a depression will commence.
LateGreatPlanetEarth
Peat
Peat
 
Posts: 97
Joined: Tue 13 Jul 2004, 03:00:00
Location: Cypress, CA
Top

Unread postby Dezakin » Mon 08 Aug 2005, 21:43:39

eric_b:$this->bbcode_second_pass_quote('', 'I') agree with deza, that at least technically, nuke power plants can provide all the power we need for centuries, if not much longer. Economically I'm not as certain.


Why? We functioned for centuries with far lower energy intensive economies, and the costs for building nuclear reactors are well defined and affordible. Supposing we somehow went on a deflationary spiral into a depression, sure we'd build less of them at first but eventually economic cycles swing up after the infrastructure adjusts. Certainly we aren't at the apex of civilization barring real cataclysm (major asteroid impact is the only thing I can think of that would absolutely end it.)

If you are talking about the intermediate time frame when oil shortages have the potential to shock the economy in potentially destructive ways, we can argue about how destructive such shocks will be, but they definately dont spell 'powerdown' of civilization or any other such nonsense.

shakespear1:$this->bbcode_second_pass_quote('', 'H')ave you guys heard of this design which has many advantages as has been run by the Germans ( Laboratory ) for 21 years? Pebble Bed

Yes. They are interesting because they have higher burnup than most LWR's and high operating temperatures, meaning higher carnot efficencies. Also their modular designs imply good economics.

But they do have some worrying features: containment buildings are just avoided in most designs, so if there is a serious accident it isn't contained. Also the pebbles are carbon coated for neutron moderation, which means that if there was some loss of coolant accident that pulled oxigen into the coolant loop, you have graphite fires that burn a la Chernobyl. The pebbles have a knack for getting stuckin the feeders/hoppers, they are difficult to reprocess, and the waste stream is volumentrically larger than LWR's.

They aren't really better or worse than LWR's, you just tradeoff some risks/costs and benifits. But you can make pebble bed reactors without neutron moderators for fast reactors for doing actinide burning if you like.
User avatar
Dezakin
Heavy Crude
Heavy Crude
 
Posts: 1569
Joined: Wed 09 Feb 2005, 04:00:00
Top
Previous
Post a reply

Return to Peak Oil Discussion

Who is online

Users browsing this forum: No registered users and 1 guest



cron