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Canadian Premiers endorse new Nuclear Power option

 
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I came across this article yesterday.

I may discuss, in the politics section of the cider press, how this great move by politicians with opposing political views to my own makes me feel, but for the moment, I wanted to bring this up, along with a link to the specific company they're looking to work with, specifically this page on the specifics of the technology involved.

I find this exciting, and seriously futuristic permaculture, in my view, because of three points inherent to the technology:

1) the heat transfer mechanism appears to be molten salt, making this an ambient pressure reactor, meaning no possibility of an explosion
2) it is well-capable of using nuclear waste to fuel its reaction
3) the relatively small (view website for human scale comparison) makes this scalable to any need.

I find this most exciting because this is exactly the kind of movement that we need to bring forward what is not only just a clean-energy source, but rather an energy source derived from cleaning up deadly messes that we have already produced, and in a manner that requires no constant supervision to remain safe.

I know that we have a knowledgeable membership here. I would love to hear opinions on this development.

-CK

 
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Chris,

I took a look at the design.  Interesting.  However it appears it does not use salt as coolant, using liquid sodium instead.  Liquid sodium does indeed have some very good heat transfer properties, but it is extremely chemically reactive.


Eric
 
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If this would deal with the stockpiled waste from the industry without creating a bigger problem down the road, it is worth at least exploring. The CBC article wouldn't load for me, but I know I'd heard something about this yesterday also. I have read elsewhere that the inputs to past reactors was actually based on what the weapons industry needed and that there were better, safer ways to do nuclear for electricity generation. I would still prefer this not be in my backyard - safe as they claim it is, my area is overdue for a major earthquake! Maybe after more testing is done, I'll change my mind - I do try to keep it open!

I still feel that as a species, we need to go a long way down the "reduce" path. If this technology just encourages more waste, I won't be impressed. If it makes changing from Internal Combustion Engines to Electric vehicles more practical, that's another matter.
 
Eric Hanson
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CK,

I want to make a couple of comments based only of the technical merits of the design I read.

So I looked at the article a little bit and it appears to be a variant of the Liquid Metal Cooled Fast Reactor (LMCFR).  These types of reactors have operated in the past and had some intriguing properties.  First off, unlike virtually every other power generating reactor (as opposed to a research reactor or breeder reactor), the LMCFR operates in the fast spectrum.  This requires a coolant other than water as water is an excellent moderator (or rather the hydrogen atoms in the water are excellent moderators).  This poses some challenges but offers some potential benefits.  The reactor used in your article appears to use liquid sodium, and not salt, as the primary coolant.  

First the good part about sodium.  It melts at just barely above room temperature, but boils at an extremely high temperature, giving a tremendous range of operating temperatures.  Secondly, and importantly for a fast spectrum reactor, it barely interacts with neutrons, allowing them to pass right through almost unimpeded (a few will get captured and form Sodium-24 which has a 15 hour half-life.  This is actually quite radioactive.  The upside is that the Sodium-24 will decay into Magnesium-24 relatively quickly which is stable.  More on this later).  Third, sodium is extremely thermally conductive, exactly what one wants in any coolant.  Fourth, being electrically conductive, liquid sodium can be pumped via magneto-hydrodynamic pumping.  This means that a series of electromagnets can be set up outside the piping and move the fluid with no moving parts whatsoever.  This is an extremely desirable quality.  Finally, and related to point number 1, the boiling point of sodium is well above the operating temperature of the nuclear fuel.  In fact, even in the (highly unlikely) event of a runaway reaction, the sodium stays in a liquid state.

But then there is the bad part.  First, obviously, sodium is wickedly chemically reactive, so any sodium leak is likely to cause a chemical reaction/fire of some type.  The third US nuclear submarine, (USS Seawolf) used a sodium cooled fast reactor.  It was small, efficient, had a very high power output compared to water cooled reactors--all desirable qualities on a submarine.  However, the sodium leaked frequently.  Nothing disastrous happened from the sodium leaks, but after only a few years operation, the sub was re-fitted with a water cooled reactor which then operated normally for decades (decommissioned in the late 90's).  Secondly, whenever reactor maintenance needs to be done, the reactor must be shut off completely and allowed to sit for about 9-10 days.  The reason for this is to allow any highly radioactive sodium-24 to decay into stable magnesium-24.  This is a perfectly doable operation, but it is just another step to go through.

Back in the 1950's, the United States experimented with a reactor called the Experimental Breeder Reactor #1 (EBR1).  This was a test reactor and only ever produced a very modest amount of electricity--basically enough to run some light bulbs.  The reactor was basically a success.  However, at the end of the reactor lifespan (a few years for that particular one), the reactor was deliberately allowed to undergo a loss-of-coolant event.  The initial thinking was that the EBR1 should be resistant to meltdowns for reasons I will get to later.  Instead, about the 1/3-1/2 top of the reactor (about the size of 2 coffee cans stacked on top of each other) did in fact melt down.  Emergency alarms sounded, but there was no explosion, fire, or any loss of radioactive materials.  It was a totally contained meltdown and in fact the reactor was rebuilt and continued to operate for years.

The reason for the partial meltdown is that Fast Spectrum reactors are extremely sensitive to the precise geometry of both the fuel and the reactor chamber.  When the reactor fuel rods over-heated, they softened and bent towards each other.  This increased the reactor output causing more softening and eventually a hot blob of molten metal worked its way down the core before the reaction stopped.  The core itself was actually partially repaired and taught a lot about how nuclear designs fail.  Importantly, there was no steam or hydrogen explosion like at TMI, Chernobyl or Fukushima.

Eventually, a second, modified reactor was built on similar principles but incorporating the lessons of the the partial meltdown of the EBR1.  The EBR2 had the fuel contained in steel rods that were more heat resistant that in EBR1, but both the fuel and steel coating were designed to expand slightly outward under heat stress without softening.  This is important because as the fuel and rods expand--even slightly--the geometry changes in such a way that fast fission becomes virtually impossible very quickly.  The EBR2 had some other changes.  The EBR1 had only a minimal amount of sodium acting as coolant.  The EBR2 was completely immersed in a pool of liquid sodium to ensure that the core would always have coolant around even if the pumping were turned off completely.  In 1986, just a couple of weeks before the Chernobyl disaster, an experiment was carried out to show the passive safety of the EBR2 design.  The coolant pumps were deliberately turned off, the temperature of the core rose and in doing so, the fuel rods themselves expanded, reducing the rate of fission to zero.  In fact, this experiment was carried out twice, and each time the EBR2 stubbornly but politely refused to overheat.  Being immersed in a pool of liquid sodium, the coolant continued to carry away waste heat via natural convection and the temperature of the entire reactor stayed well below the design limits.  There was no core damage or damage of any type and after the experiment was over the coolant pumps were turned back on and the reactor resumed normal operation.  The EBR2 continued to operate without incident until it was de-funded in 1994 and decommissioned.

CK,  The design you showed does have intriguing properties and in general is much better than the solid fuel water-cooled reactors we use today.  There is more intriguing reactor physics I could go into, but I will end my post here with this one.  Personally, I still think that the molten salt reactors are the safest ones out there, but this is not a debate.  It is a very interesting design with some very interesting potential properties.  Hopefully such a design has the passive safety inherent to the EBR2.

Eric
 
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Thanks, Eric. I sniffed out the rat, but I needed someone to kill it and read its entrails for me.

Part of what has me interested here is the fact that, with the appropriate branding, this could be the focus of a bipartisan, multi-level cooperation that might work to counteract a lot of the partisan nonsense we see today. Cheap, safe power would probably drop the cost of fossil-based energy even further, as these things would be using an hazardous waste product as their fuel, and in all likelihood would be situated primarily on sites that already house or produce said fuel.

And how do we term this stuff? What do we call an energy source that literally sanitizes the environment of its own hazardous byproducts, and those of the generation that preceeded its development? How would this figure into carbon credit and offset calculations?

How much carbon could be sequestered using energy-driven chemical processes, or how much synthetic fossil replacement could be synthesized from atmospheric CO2 and water (at that point the combustion of which would be as carbon neutral as burning wood for heat off of one's own woodlot) for sale in place of fossil fuels obtained in an environmentally ruinous manner?

How much fossil fuel wouldn't be consumed if these were brought online?

Handled right, this could have the Ford government beating their heads against the wall for abolishing Ontario's cap-and-trade program, worth something like $1.5 billion CAD at time of cancellation. Is it possible to know how much money this could be worth in carbon credit terms per gigawatt?

-CK
 
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CK,

You touched on an issue in your last post where I would love to see more development.  It is not specific to nuclear and pertains to making stationary power generation into a mobile form.  For applications like small and compact cars, I like the ideas about battery electric vehicles (BEV).  At present, BEV’s work reasonably well for options like the Nissan Leaf.  Certainly there is room for improvement, but the basic concept works at least reasonably well.

I am not certain how one gets to something like a BEV minivan or small SUV, and at present, heavy equipment seems completely unsuited to BEV.

On the other hand, a technology I would love to see develop is a practical fuel cell.  Around the year 2000, I had a lot of hope that fuel cells were right around the corner.  At the time the Proton Exchange Membrane fuel cell had just become semi-practical.  A PEM would be much more efficient than a gasoline engine and likely better than a Diesel engine.  Unfortunately, hydrogen storage was and still is a problem.  On a per-volume basis, hydrogen just does not offer a lot of energy.  Even liquid hydrogen just does not have a lot of energy (but on a per mass basis it is great which is why it is the preferred fuel for NASA rockets).

There are some other fuel cells that could hold promise.  Some are attached to an on-board reformer that would allow something like gasoline to be stripped of its hydrogen atoms that could then be used in a PEM, but that process would require energy not available for the fuel cell.  Another option is called the direct methanol fuel cell (DMFC) that could power a vehicle based fuel cell directly from liquid methanol.

While these have interesting potential, I have seen no development since about 2000.  Mostly this is hypothetical but it could be a replacement for many internal combustion engines.

Just a thought,

Eric
 
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Eric Hanson wrote:CK,

You touched on an issue in your last post where I would love to see more development.  It is not specific to nuclear and pertains to making stationary power generation into a mobile form.  For applications like small and compact cars, I like the ideas about battery electric vehicles (BEV).  At present, BEV’s work reasonably well for options like the Nissan Leaf.  Certainly there is room for improvement, but the basic concept works at least reasonably well.

I am not certain how one gets to something like a BEV minivan or small SUV, and at present, heavy equipment seems completely unsuited to BEV.

On the other hand, a technology I would love to see develop is a practical fuel cell.  Around the year 2000, I had a lot of hope that fuel cells were right around the corner.  At the time the Proton Exchange Membrane fuel cell had just become semi-practical.  A PEM would be much more efficient than a gasoline engine and likely better than a Diesel engine.  Unfortunately, hydrogen storage was and still is a problem.  On a per-volume basis, hydrogen just does not offer a lot of energy.  Even liquid hydrogen just does not have a lot of energy (but on a per mass basis it is great which is why it is the preferred fuel for NASA rockets).

There are some other fuel cells that could hold promise.  Some are attached to an on-board reformer that would allow something like gasoline to be stripped of its hydrogen atoms that could then be used in a PEM, but that process would require energy not available for the fuel cell.  Another option is called the direct methanol fuel cell (DMFC) that could power a vehicle based fuel cell directly from liquid methanol.

While these have interesting potential, I have seen no development since about 2000.  Mostly this is hypothetical but it could be a replacement for many internal combustion engines.

Just a thought,

Eric



Toyota has been working on fuel cell vehicles, and I know Kenworth is also experimenting with one.

I think the biggest issue with fuel cells right now is their cost.  I don't know the actual numbers, but my recollection is that even for something like what Toyota is using in a small sedan the cost is somewhere in mid 5-figures to low 6-figures, just for the fuel cell.  That's a whole lot better than 30 years ago when it was a solid 10x more costly.  But, to be practical, fuel cells need to come down by another 90% on price.

Overall, from an engineering and practicality perspective, I like fuel cells a lot more than BEVs.  You get the benefits of a BEV in that there's no tailpipe emissions (other than water) as well as the huge low-RPM torque.  And you get the ICE benefit of very fast refueling time and lighter overall weight vehicles.  And it doesn't require a huge change to the electrical infrastructure to convert the North American vehicle fleet, like a wholesale switch to BEVs would require.
 
Eric Hanson
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Andrew,

You are absolutely correct about the price of the fuel cell at present.  I have a friend who invested in a company that makes a propane fueled fuel cell for operating the indoor forklifts like at s Lowe’s or Home Depot.  This is a niche market and I really don’t know how well that stock is performing.  It is an interesting concept though.

Eric
 
Eric Hanson
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Even if you just find the physics of nuclear reactions interesting, you might like this thread I started here:

https://permies.com/t/128873/natural-nuclear-reactor#1012676

I detailed how an actual nuclear reactor once occurred naturally here on earth.

Eric
 
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