The Liquid Fluoride Thorium Reactor: What Fusion Wanted To Be

Uploaded by GoogleTechTalks on 19.11.2008

>> Welcome everybody. I'm going to be--try to be short because we're running a little
bit late and then there is a talk after us. So, today we're going to have a talk about,
I don't know, alternative energy. I think it's important. I think if we really want
to make a denting CO2, we need to be looking at some serious stuff as well. And for this
purpose, we have today Dr. Joe Bonometti and he is a NASA Chair Professorship--he had a
NASA Chair Professorship position at the Naval Post graduate School. He worked at NASA for
10 years as a technology manager, lead systems engineer, nuclear specialist and propulsion
researcher. He's basically a rocket sciences guy. He--their manage--manage the Emerging
Propulsion Technology Area for in-space systems, the Marshall Aero launch team, as well as
a variety of auto power and propulsion assignments. After rendering a doctorate degree in mechanical
engineering from University Of Alabama in Huntsville, he spent several years as a research
scientist and senior research engineer at the UAH Propulsion Result--Research Center,
where he served as a principal investigator and manager for the Solar Thermal Laboratory.
He has worked as a senior mechanical designer at Pratt & Whitney supporting aircraft engine
manufacturing at--and at the Lawrence Livermore National Laboratory within the Laser Fusion
program. He's a graduate from the United States Military Academy. I think you'll find out
that he knows what he is talking about and I am eager to hear what he has to say. So,
please give him a warm welcome. Thank you. >> BONOMETTI: Thank you. That was a great
introduction. It's a blessing to be here. I have a lot of material to go over so I'm
going to suspend some of my normal comments and jokes and go right to it. I planned to
be talking about this in context of fusion but I'm going to hold back some comments for
there to get through the material and get to the questions. One note in the beginning,
I come here as an individual. I don't represent any agency or organization. There's a loose
fitting group of people around the country mainly specialist, technologist. They're interested
in this field; both in energy and in particular thorium and that we all have day jobs, fortunately
good paying day jobs for the most part. And so, we come to give this information out freely
and examine this idea and the use of thorium as an energy source. Outline; I'm just going
to mention that I talk about systems engineering because I've taught that as well as my thermodynamics
and nuclear background. You only see a little bit there of that. Some assumptions; I'm assuming
that most people understand the energy crisis. It's global in nature, it's--nobody's got
a quick fix, at least nobody would agree what the quick fix is. Thorium is not going to
be commonly known especially as an energy source. Increased electrical capacity is very
important to the overall energy consumption. And the last thing is, energy equates the
state or the standard of living and one of the last green energy forums I was at listening
to, they equated 258 slaves if you will working full time and hard labor, 365 days a year
for each person in the United States. You can see that that level of energy is what
gives us a standard of living. This slide comes from Lawrence Livemore Laboratories.
It's one that I would spend a long time on. I think it has a lot of great points to be
made. I just say that if you don't know what quad is 10th of the 9th, BTUs. It's a lot
of blot of energy and if you just take all the energy we have in the United States and
break it up into 100, you get 100%. So you can see, oil is around 40% and that line is
the thickness--equivalent to that. You can see that most people would say we want to
increase these desirables, okay. And notice that the desirables are pretty thin and it's
kind of hard to increase them. These are the ones we would probably want to phase out more
as well as less oil. We have huge energy losses and electricity production, about 25% efficient
overall. Conservation is great, we do it at home. Mostly engineers, if they don't have
to create any entropy increase percent in the universe; they would like to minimize
that. But at the same token, you can see that we've paid the price up here. And that conservation
as much as we want to, there's not a whole lot of gains there, in these two areas. The
other thing is, if you notice right here, you can't make that line go to zero. Thermodynamics
says you always have to have a cold sink. You always have to move energy. One example
I talk about is wind; that you can put up a windmill and you can put another windmill
behind it and you're going to extract a little more energy and slow that air down but there's
a fundamental limit. If you put too many of them in there, you'll not only get the last
one to not move because there's no air flow, okay, you've actually affected all the windmills
in front of it, until you get no energy. So, there's a fundamental limits to thermodynamics.
You always have to have some lost there. And of course, most people would consider that
you want to increase the electricity flow into cars or transportation areas as well.
So, what you really want to do is, if you can't roll these things fast enough on the
order of this size, you really want some new energy source, something big, something, you
know, it comes in, it can be readily built and provide that very big, wide line. Something
like fusion, right? Everybody would like to see that. Well, I'm here to talk about thorium
and whether thorium can be that line. And also, what's the best way to extract that
energy? Now, we're now getting to--go out of details, you can take a little bit of thorium,
put it in a normal reactor and you get some benefits out of it, okay. But it's not an
end-all and it doesn't extract all the energy out of that thorium that you'd like to and
it doesn't mitigate all the problems you have with today's nuclear power. Thorium; just
for background, is an element. 1828, it was discovered. It is slightly radioactive. It
got a very long half-life, that's why it's around and it provides real background radiation
along with uranium, most of it comes from that. Just a little bit of thorium that's
always around in the soil and in rocks and minerals. The only thing I'm going to say
here is that thorium is not really commercially used for anything of much these days. It is
a metal. It's got a very wide liquid range, some other interesting properties. I'm not
going to go into any other details to know that--commercially, it's not a big deal. Now,
this is a log scale of what's available in the Earth's crust and you see that the beginning,
you have oxygen, silicone, aluminum. Down here, at a 100 parts per million, in this
box here, you have copper in the middle and at--towards the bottom, you got lead and thorium.
And you can see I expanded this little area out. Uranium is about four times less than
thorium. Boron, which some talks have a--even at Google, we've talked about fusion using
boron, all right. It's there. It's readily available but what's interesting is the uranium
that you're really interested, the one fissile material, it actually split, is way down here,
orders of magnitude less. So, thorium, on theory--theoretical basis; the United States
has about 20 % of the world's reserves. To put this in perspective, one would say, if
you replaced all the energy--electrical energy generation in the United States that you saw
before and I'm not suggesting we do that. A lot of other energy sources will play but
that's about 400 metric tons. One mine can produce about 40--500 metric tons per year,
you can see that's 10 times the amount. The United States has actually--the government
has buried a bunch of thorium. They didn't know what to do with it. After paying for
it and storing it, they just put it in the ground literally in these casts. And you can
imagine that's--even at this--huge amount energy usage that last 8 to 10 years. In a
practical sense, this would last us probably 25 to 50 years. And you've certainly have
plenty of thorium available around the world. That's not enough. Like fusion, we can go
to moon. The difference is there, we don't have to mine the entire surface looking for
it. Thorium gives a nice signal and you can detect that from space and so we can map it
and where the hotspots are, you know that there's a pretty good thorium deposit there,
same with Mars. So, we know that it's out there and the asteroids, thousands of years
worth of power. Now, because of my systems engineering background, a little bit of the
flavor I'm going to give you is in the vain of how do you select things or systems engineering
criteria. And this comes from the aerospace that about 80% of a projects life cost and
benefits are going to be locked in the first initial decisions you make. And that pretty
much for all technologies especially hi-tech technologies; that holds pretty well true,
70%-90%, somewhere in there. And the reason is that it sets your theoretical limits, it
also--at the time, you have your least real world knowledge of how you're going to build
or how you're going to go about doing this project. So you--the thing I try to teach
is you look for the inherent balances, something untouchable, at least--reasonably untouchable
and a growth factor that your concept will gain and exceed what your goals are. So let's
take nuclear technology that we see today. You know list the pros and cons that are shown
here. Most people recently have looked at, you know, no green house emissions and that's
because in this case, about 3rd comes from electricity and before majority of that is
coal. Nuclear doesn't have that. Now, to be very honest, one would have--and analyze,
well, how much resources does all this make when I go to build a plant and how much CO2
do I produce? In the case of a nuclear energy, there is some but over the lifetime and the
amount of energy a nuclear plant produces, this is probably--pretty a fair game to say
it produces no CO2, but it's something you need to be honest about and compare. What
if you can take some of the cons out of there, the safety fears and long term sustainability
and terrorist or proliferation issues and make them go away or at least minimize them.
It sounds like what fusion wants. Another thing on systems engineering is the concept
of power density and efficiency. I can't go through all these but obviously land usage,
you know, the maintenance cost, anything that you have to deal with, the overall cost of
a lifetime a project--smaller is not just convenient. It drives--90% of the time, it
drives the cost and therefore--at least, the social cost, maybe not in a particular market
but across the board, it usually does. And you'll see that that's very important for
power density and efficiency. And example that comes into mind is the cost material
labor and then the distance from the end user, and all these other factors that factor in.
I'm not going to go into a big detail. This is, you know, information that's available
and have been readily been talked about. Natural gas turbine engines is about one-tenth the
amount of steel for example in a nuclear plant and a nuclear plant is actually pretty good
compared to some of the others. But you see that in recent years, what are we building?
We're building these very expensive, difficult gas using machines that are very hi-tech,
yet we're building more of those. Why? Well, because overall, the resources necessary to
produce that and to meet the demand now makes you go for these things. And that's what--that
what's been happening. So, in the light of the--what fusion wanted to be; safe, proliferation
resist, et cetera. That was one of the jokes. Today, we have basically large plants although
there were a couple of Google talks that's talking about making fusion in a way that's
smaller. I would love that to happen but basically, we've got these very large plants and of course
they use a lot of it--they produce a lot of energy but they also absorb a lot of energy
in producing the energy. So your net gain is not as good as you would want. Kind of
get into the history as well as the physics at the same time and talk you through a little
bit about thorium and why we ended up with a--the LFTR concept. Three basic nuclear fuels
everybody should know, you know, uranium-235 is what's naturally found, that's what we
can start with. These two have to come from fertile material, we have to make them, they
aren't found in nature. And in history, everybody was working on weapons and so you have an
enrichment facility, you need a weapon designed, you need fabrication techniques. For the uranium-238,
you need a neutron source which also usually starts with the uranium-235. You chemical
separate, you need a new weapon design, new fabricating techniques, you get a slightly
better bomb, so I'll say on that. And thorium, well, they discovered, you need the same thing
you need with the uranium-238, chemical separation, but then there's some contaminant in this
usually and which should go to an enrichment facility but it's a hot enrichment facility.
You need yet a new weapon design, a new fabrication techniques to get the same kind of bomb. Well,
obviously, these two are what the world has shows in the --to work on. Well, at the same
time, most of the people that worked on those projects also were good people trying to say,
"What good can we do besides weapons?" An electricity production was one of them early
on and they had the same problem. They had the same materials to start with. You need
enrichment or heavy water production, a new--a fuel design, okay. A little bit different--but
it's still solid fuel, fabrication and then electrical power. I say short-term electrical
power because at the time, they really underestimated how much uranium-235 was in the world. It
was a little bit more than they actually are accounting for originally. But at world usage
at the U.S. levels, it's still a very true statement to say, you know, there will be
peak uranium if you--if you base everything on uranium-235. Well, you can go with breeders;
fast spectrum breeder reactor, you need some sophisticated controls. We'll talk about that
in little bit more. Some fuel design and you get electrical power but you also get a whole
lot more production of plutonium which has been used for nuclear power and run other
reactors produce electricity or of course, you can use that for weapons. Thorium, on
the other hand looks a little different at each time. Thermal spectrum, chemical processing
and you get electrical power, it's very hard to get any extra out of it and I'll explain
that here. Enrico Fermi argued for the plutonium-based economy essentially. And one of the reasons,
you get three neutrons on average per fission and the real key number you want to look at
is this blue line and that is the number of neutrons that come for absorption and you
need at least two. You need one to spilt, and one to breed your next fuel. And so, in
reality, you need a little bit more than that because losses through the reactor, you got
to make it reasonable. So you have to work this thing, it doesn't work here at all in
thermal spectrum, you have to work up here in the--near the--what I would call the bomb
spectrum, okay. You're using now the fast neutrons coming off the reactor from the fission.
You're not slowing them down in a thermal--in a thermal sense. And you can see that this
number really climbs very good, which means you get a whole lot more than two, which means
you get production of plutonium or you can use it for production of plutonium. Well,
Eugene Wigner at the time argued, "Well, you know, it's great for weapons but we really
want to base our economy on thorium." It's more available and more important. It runs
on a neutron spectrum--a thermal spectrum such that it's a lot safer, a lot easier to
control and you can, you know, use these reactors. It is--this is a very difficult reactor, very
touchy reactor to work. But of course, it doesn't produce much because you see the average
from the fission is only two and a half and the actual absorption averages a little bit
below that, okay. So you're above two which is enough, but with real, real losses, you're
not going to breed a whole lot of extra material out of this--out of this system. Well, historically,
what did we do? We went from weapons to--they're not on the list. There is Eisenhower's Atoms-For-Peace
program which is trying to say, well, we've spent all this money, we want to look a little
bit better in the eyes of the world. Let's produce electricity. But you're using the
same infrastructures, the same people, the same needs and desires you poured into here
to--Shippingport was our first electrical plant and sure enough, that is the base product
for our surface ships. So, a little bit of entangled there, it wasn't exactly Atoms-For-Peace
and a conventional sense of what's the best way to produce electricity. Well, is that
a good or bad decision? Well, I'm not sure I want to sit here and debate that but, you
know, at the time, urgency of war, the fact that the weapons were unsophisticated designs,
you needed a lot of material for it, the delivery systems were horrible, okay. And so, you needed
a large number to be a credible defense, safety environment; those kinds of things weren't
considered as much. Compared to today, obviously, the very efficient designs ICBMs are highly
accurate, they need to scale down. We almost have too much material for weapons. And of
course, safety environment proliferation issues are [INDISTINCT] concerns. Maybe it was right
then, maybe wrong today, people can decide that. Well, in the tale of the nuclear reactor
thorium, engineers don't want to give up. When they see a good idea, they dog it, even
though programmatically and the money and the funding was completely cut off, they went
around and said, "Look, air force, you don't--you don't have ICBMs yet. You need a credible
defense to get your weapons out there, something that could fly a long time, how about this
nuclear airplane?" Now, the only way that this would ever do in a normal reactor is
if you have a liquid reactor. And so, they started a program, they sold air force on
it as crazy it is. And I understand that somebody recently has said something in England, I
believe about this. I would not like to see nuclear airplanes as our base of commercial
flight. I can talk about that at some other time for the reasons for that. When this reactor
program started out, they did 100 hours, a high temperature. I believe that maybe the--still
a record certainly for the overall reactor running that long, that hot and that's 1,500
degrees Fahrenheit, very much hotter than most reactors can run. Two things that came
out of this, one the fission products were naturally removed as you were pumping at it,
which was really nice, to get rid of the poisons. And two, the load-following capability which
was essential for the airplane application--in fact that you wanted to throttle something
without control rods have instant response from the reactor and then throttle back if
you needed to, to get your power. This reactor in the fluid method was able to do that on
con--unlike on conventional or conventional reactors. Well, that program died pretty quickly
as soon as the air force realized they could do the job much better with missiles. A missile
program was--went full ahead and that one was cancelled. The engineers still wouldn't
give up, okay. They [INDISTINCT] down in--or Oak Ridge National Laboratory in a small program
but they ran a small program from '65 to 1969. And the main thing I'll say about this--we're
not going to go to the great details of molten salt reactor Experiment was affected. They
ran it 24 hours a day, three shifts everyday but nobody wanted--none of the engineers wanted
to stay for the weekend. So, they shut it down on Friday night and they started it up
regularly on Monday morning. Something that's totally, you know, not even thought about
today in nuclear power plants. It is a base load, when it goes down, it goes down for
a long time, you don't get to restart it. The end result today, most people think of
molten salt as this gigantic reactor, something very large. They even have some control rods
that's so large. Single fluid which means your thorium is thrown in with the uranium
in the reactor itself. And you do--you do have a processing system; you have a freeze
plug which I'll show a little bit later and you have this Brayton Closed-Cycle Turbine
System unlike steam that is an advantage to this idea. Well, if this was so good and the
common question is why wasn't it done? Well, hopefully I kind of hinted at that along the
way the establishment on the plutonium industry and the needs there. The fact that this is
a liquid system, it's daunting, it's different than just nuclear energy, it's a lot of chemistry
involved, there's an existing mindset that had to be broken. And Dr. Weinberg who also
hones the patents for the reactors we have today, who helped basically train Admiral
Rickover and suggested what the reactor for the Nautilus, was. He was hoping that this
reactor which he worked on for a long time would be the eventual power reactor technology
that would use for electricity. Another person--his memoirs, deputy director at Oak Ridge also
pointed out that it was an Oak Ridge project and therefore, it was considered just their
own pet project and it was very hard to break out of that mold. Again, the existing bureaucracy--I've
heard a lot of talks on the fusion as well, the same kind of mindset we are trying to
break, what the common large program has in the government. All right, why is it so different?
Liquid core, I mentioned that and the fact that it is thorium and that you have this
chemical processing system. And you can see at room temperature--this is a crystal, it
is a salt and when you heat it up, it becomes a liquid, a little bit thicker than water,
you can pop it around. Last thing on the history, Admiral Rickover in his program, he managed
to put together a gigantic organization to build not only the Nautilus but the whole
nuclear navy and it stands today. He's done a very good job as far as establishing safety
record and the navy is excellent in that but understand--inherently, it's not found in
the reactor. It's found in the very strict rules, the blind obedience, the very well-trained--long-trained
process that you have to do with the sailors that run these reactors. So here's the path
that we've taken, the typical nuclear reactor with this giant vessel and the question is
have we made the best decision then or are we making the best decision now? And I'm going
to--then propose that LFTR is something that is what fusion promises. Some technical details;
LFTR is a technology or architecture of a technology, I should say, it's not a specific
design but it has certain design characteristics. Two fluids, the fact it's atmospheric pressure,
very low pressure on the vessel. It's going to be high-temperature. It's going to have
chemical extraction; I'll explain why that's necessary, thermal spectrum and then the Closed-Cycle
Brayton System instead of steam. The reason why you have--this is the chart of the nuclides--the
reason why we have to have extraction is that thorium with the--this is protons 90, it absorbs
the neutron, it becomes thorium 233 which beta decay on 22 and a half minutes. Everybody
knows what beta decay is--goes to protactinium. Protactinium, 27 days half-life, it also beta
decays and becomes your fissile fuel. Uranium-233, that's what you'd want to get in your reactor
fuel. Now what if we leave the thorium--I mean the protactinium in the reactor, this
is what happens. You get the same beginning, you get thorium beta decaying the protactinium
but now you have the problem of absorbing a second neutron which is fairly highly likely.
And seven and a half hour--or seven hour--or half-life, it will also beta decay to uranium-234
which is not fissile. Now, you could absorb yet another neutron here and jump to 235 and
with another neutron split the 235 but obviously, that chain is using way too many neutrons
and the reactor would stop under that--on those conditions. And there's all this probabilities
of how much absorption and there are other decay methods that you have to take into account.
So, that's the main reason why you want to take out the protactinium out of the reactor.
So, the architecture for LFTR starts out with the minimum core of fissile material that's
hot. The four corners just kind of remind you of the--the basic print is what are you
trying to--the goals you're trying to get to which is a safe compact reactor, something
that--proliferation-resistant, waste reduction, covers that amount of electricity you need,
that great big blue line and do it quickly as well as cost-effective being--effective
connecting to the grid. So, the core is just hot, you can pump in and out, drives the turbines,
you understand that. The blanket around it reflects the neutrons back in or the thorium
that's in the blanket absorbs and becomes your protactinium. You have to take out the
protactinium, there is the chemistry and let it decay and then that produces the U233.
And you can actually extract the products--the fission products and other things out of the
reactor as it's running in this liquid state. Look at the inherent advantage, this is against,
systems engineering, everybody has desired goals and you kind of just specifically list,
well, what are those goals were, the cost. Well, it's a low fuel price, low capital cost,
long life, low maintenance so those kinds of things--transportation. You break all those
down and you trace out what your inherent properties are to those and you see whether
they're--you're matching up or you're getting what you really want to. So, if we pick a
couple of these, here's liquid core, you've got homogeneous mixing which means you don't
have any hot spots, which is a real concern in conventional reactors. If one spot gets
hotter and it continues to get hotter until you have to melt them. You get to burn up
all the fuel because it's constantly being moved around in the reactor and no fuel shut
down because you can fuel this continuously. The expandability of the fluid gives you a
large negative temperature coefficient which is where your safety is at. No separate cooling
system, that's one less system and the big thing is the safety; the fact that if you're--there
is no coolant to get rid off in order to have a meltdown or a problem. And of course, drainable,
you know, I'll give you an example of that. If you have this very small reactor core and
you leave a tube out there and this is very hot liquid--as long as you keep that at room
temperature by blowing some air across it or in this case, helium--forced helium tubes,
that salt will freeze. It'll make a plug, if you got a crack in this thing, actually
it will actually leak out and probably seal itself, okay, depending how the design of
this is. But the point is if you lose power, if anything happens; somebody throw a grenade
in this thing this--or this gets hot, too hot for any reason, that plug will always
melt and drain into a passive pan which is going to hold the heat and then the radiation.
If everything is okay, you just heat it back up or even turn it right back on and if it's
liquid state, it takes a little while for that heat to dissipate and you can pump it
back in to start up. So, instead of being like really cautious about shutting down your
reactor because you'll black out half the neighborhood or whatever and take days or
months, if not years to restart, you can go ahead and shut things down and go, "It was
just a mistake." And immediately go back on line. So, actually there's inherent safety
in there because you could use your safety system all the time. Actually, I need to go
back. All right. Thorium advantages here, that it was abundant, I mentioned that and
the fact that it's not fissile, okay, it means it's not weapons usefulness in which case
the less terrorist interest again goes to cost and safety, security, can't explode.
Look at the uranium cycle compared to the thorium cycle, you start out with a whole
lot more mining with the uranium cycle, you have a whole lot of yellow cake that you make,
everybody recognize that but then you got to enrich that and then make these pellets.
It's a very expensive process; the security to do this process is very expensive much
less the actual process. You end up with a whole bunch of depleted uranium, it's still
useful in some ways and not useful in others so I don't know what people were doing with
that other than letting it sit on the ground, it doesn't go to Yoko Mountain. You need a
very big plant, as you saw before, you--a very large reactor with a vessel that can
hold a ball of steam or any explosion that can happen here because of the very high pressure.
Big turbine plant next to it and you produce a whole lot of spent fuel and you need Yoko
Mountain for 10,000 years. The thorium cycle, you need one ton, this is for the same amount
of energy, one giga watt for one year and much more plant, low pressure, the Brayton's
are much smaller, much more efficient as much as 50% efficient or better compared to about
35% best you can do for steam, one ton of fission products. But the big deal here is
that in--within 10 years, most of that, 83% is going to be backed down to safe radio--background
levels, which means you can take those products which actually were produced in the reactor,
there's some very interesting things you can get out of that and you'd sell some high quality
materials. And the remainder only needs 300 years approximately for storage, which you
can imagine that--the finding a many places around the world that can handle that and
you can imagine making storage vessels that are, you know, casts that can last 300 years.
Well, proliferation risk; one of the things that happened with this particular process
with the LFTR processes as we see it, there's going to be a little contamination of uranium-232,
you just can't help it, I'll show you that in minute. And it has a decay chain; it gets
you down to thalium-208 which has a hard gamma emitter which makes it a very nasty stuff
to deal with. This is where the uranium gets in--the 232 becomes. There are certain reactions
that can happen. I don't have time to go through the details. If you have 1% of uranium-232
in the material and you're holding it, you have about three--or three minutes, I believe--well,
less than three minutes before you get your full five rem dose which is considered, you
know, your top level. I think it's within a half in it--no, within--yeah, half an hour.
You're feeling the effects of radiation poisoning and a couple--and within two hours, you're
probably likely to die. So, it's very hard to handle, it also means separation of a nation
who wanted to use this as a material for weapons, it would be a hot enrichment environment to
deal with. The radiation hurts the electronics as well as the explosive material within the
weapon so they don't shift--they do not--their long--not very long half-life as far as the
shelf life of the reactor--of the bombs, so. Okay. On the fluoride salt itself, ionic chemical
stability is very important. I'll show that in a minute. The fact that it's very high
temperature and a little vapor pressure means you run very high temperatures. And again,
each one of these things room set, temperature solid, like I explained before leak resistance,
et cetera. So, look at the radiation damage in a conventional nuclear reactor. It's going
to have cladding, all the temperature and heat is built up within that cladding and
that cladding can't break. So--or you lose the noble gases, the krypton and other things
that were radioactive. And so, you end up having to pull out this core all the time
and not burn up all the fuel because there's physical damage being done to the solid, where
is if it's ionically-bonded in a liquid, the ionic bonds don't care. They're going to move
around as they need to and reassemble and you always have that ability to withstand
a lot of punishment in the reactor. Another point of this is that the salt are actually
very low corrosion and the way to briefly demonstrate that, here is a typical salt in
the reactor and the larger the number, the better minus 104 and this the freeb--free
energy--Gibbs free energy here. A chemist will say you need a difference of 20 between
it and let's say a wall material, or a vessel material such as--here's iron and you can
see that's about double the difference between those two. So, it's pretty chemically stable,
considered almost a noble chemical reaction in the reactor. Internal processing; we have
minimal, physical--inventories so if the reactor is small, there is no fuel fabrication, obviously
that drives a lot of your cost and the big thing is you can extract both poisons and
valuable materials out of the reactor. This is a little more detailed than the one I had
before. What you're doing is you're pumping out of the core and your fluoride--just fluoride
gas through the salt and all the uranium products are going to come out as uranium hexafluoride,
which means it's a gas and you pull it out and it re-introduce any uranium that it has
not burned into the reactor. The rest of the salt goes through, you get back some distillation,
get out the fission products and what's left here is you can separate this. And this will
probably take an economic analysis of how much time and effort would you do to separate
these things. You do need a central location plant where you take little bottles every
once in awhile out and centrally process or do you incorporate it like you do the actual
breathing process within the reactor itself? This would all be self-contained in a reactor
vessel. The blanket on the other hand comes out and I'd like to think that is a--it's
a reactive extraction column--if a chemist--it's like a catalyst. But they say that's a bad
word so don't use it. For me, it's a catalyst in nature. In fact, that you put in the thorium
appear and the thorium will go back into the blanket salt and replace the protactinium
which can be extracted out and put in the decayed tank. Same thing here, you just flow
gas through that, fluoride gas, all the uranium that's produced, whenever it's produced is
able to be put in--back into the salt and back into the core. And very quickly on the
Closed-Cycle Brayton, just to say that this could be air cooled, heat rejection as wall
as verbal impact pressure allows you to play with the size and the efficiency of the system.
And this just shows--this is the advanced boiling water reactor typically looked at.
And again, a very large building, no matter how you do these things, the LFTR concept
would be very much smaller, the whole reactor core would be something that size with the
entire Brayton system not much bigger. And it just shows again the difference in size
of a comparison of a Brayton system versus steam plant and some of the listing of reasons
why you would think that the cost of this whole system would be significantly less than
existing nuclear power plants. Okay. Well, the disadvantages, I think I explained some
of these. It's unknown; it's going to be different from what the existing infrastructure is going
to support. It does need a charge of uranium-233 or some other fissile material but we suggest
doing that because it keeps it--the whole reactor clean. And here's a comparison--basically,
I've covered most of these, everything from the waist--relative waist 130th, 10,000 years
versus 300 years, the fact that you can burn almost 100% versus 1% and the best reactors
are planning a couple of percent maybe, two or three of the total fuel usage, as well
as being higher efficiency, lower pressure, air, water cooled. And in unique applications,
this should scale down as well as scale up if you want to make large plants but it also
could spill onto the back of a semi-trailer, that size typical. It would obviously be very
advantage to the navy because even in their smaller vessels, they can't build these--their
existing reactors to fit into the [INDISTINCT] ships that they have. We like to talk about
submerged units because they're really not seen. They put them in rivers and they're
very small, very invulnerable to attack or other things. And then if you really want
to use other processes, high temperature directly from the reactors, it's very useful for--one
is mobile. It can go to a site for shell oil extraction. It's--it couples very well with
desalination for water processes, hydrogen production as well because of the high temperature
nature of the reactor core. So hopefully, I've covered a--the brief background. These
are the main things that we try to achieve with the technology. Those were the driving
goals and then how you would actually put the reactor together or so the specific details
are driven by what you're trying to get out of it. And the primary reason why most people
look at thorium is because of the unique nature of being able to produce a huge amount of
energy for a very small amount of resources per mega watt being produced and can readily
be put together fairly quickly. So this time, I'll take questions. Yeah?
>> The U233 that's re-injected in the core, how do you keep the 232 out of it? I mean,
it seems that you introduced 232 and that it's something you don't want to go anywhere
near it. >> BONOMETTI: All--the--what happens to the
core when you introduce the 233 and the 232 in the reactor core? Well, first of all, a
reactor--or any reactor is very, very hot and you can't go near it. It's going to have
a lot of radiation going on. So, adding the 232 in there is not making any significance
difference in the overall radioactivity in the core itself. Definitely, there is a small
poison that sits in there but it's a very small trace amount. It's when you take it
out that unless you separate it out, you always have hot uranium and the difference is the
separation is chemical separation versus the uranium-233 which is what you want for the
weapon and uranium-232 which produces this gamma all the time and it's the key chain.
It has to be done with separation techniques that are more common to weapon development.
Did I get the question right in it? >> I was just wondering if it makes the design
of the reactor [INDISTINCT] because the U233 is actually part of the process? So, you know,
if the materials you use for example is part of the pumping, you know, we would run into
problems if your plant becomes contaminated with some 232.
>> BONOMETTI: No because there's--again, the question, I--it was--is there an issue with
the 233, 232 in the reactor core or as it comes out through the piping because of this
radioactivity. The decay products in the reactor overwhelm that. There's just one small source.
The reason why it's significant for proliferation issues is the fact that it's hard to separate
because it's from the stuff you want because it's still uranium, chemically. As far as
the reactor itself, any of the pumping of the pipes and everything else is going to
see some level of radioactivity just because of the decay products. Those decay products--what's
nice about this reactor are always kept in a minimum because you can take them out. The
gases, anything like krypton or whatever comes out in the pumping process. So, it's actually
a cleaner reactor if you want inside the reactor and it wears and tear radioactivity-wise less.
Yes? >> What's your estimated cost for the consumers
say, I don't know, a wholesome price or retail price if you were handling--what are the barriers
to presume? >> BONOMETTI: What is the price at the meter
at the end of all this? We haven't gotten that far in economic development of what that
would be. The argument here is that the technology and the research has been done and there is
a systems engineering point of view that you will say, "It will be less expensive." Exactly,
we're estimating 20 to--or I think it was at 30%-50% less a more specific design. Remember,
everything is being done on everybody's own time. This is a grass root effort that, you
know, we hope that somebody with the government or somebody else wants to pick this up, it's
all free knowledge but that's--it was a great question. Did I answer the other part of the
question? There was cost, electricity and then?
>> What are your barriers? So basically, [INDISTINCT] >> BONOMETTI: Well, the barriers--to put this
together? >> Yes.
>> BONOMETTI: Couple of them. One of them would be that, you know, the nuclear industry
is run by the--by the government. You're going to have the government blessing on something
unless you leave the United States or whatever. There are other countries that are looking
into thorium but again, not significantly. And so, I think the barrier is, you know,
those types of things. It is a nuclear process and you're going to have to deal with the
proper regulations to make--meet that. Yeah, you go.
>> [INDISTINCT] and can you explain that [INDISTINCT] >> BONOMETTI: Negative--yeah, let me go back
to the slide. The--basically, it's the ability of the reactor to respond in producing less
power as the temperature goes up. So, as the reactor core--a normal reactor, when the temperature
goes up, okay, there's--usually the core temperature--what do you call it, is moderated with the water
and you get less power being produced. Okay. Maybe you flow more water through the reactor,
for example. This expands itself, the core being liquid squeezes out and the less density
you have, the less fuel you have in the reactor, therefore the less energy you can produce.
>> [INDISTINCT] it's thermal [INDISTINCT] >> BONOMETTI: So it's thermal. It's based
on thermal expansion on how much fuel you're actually having in your reactor. In the same
token, if your generators are producing more electricity because of the higher demand,
it sends back that fluid colder which is denser and therefore it will have more energy and
it is a natural process within the reactor itself. That's a common nuclear, you know,
I guess determination of how safe a reactor is. It's how good that coefficient is. Yes?
>> [INDISTINCT] what are the engineering challenges involved? Like, it strikes me that, you know,
pumping extremely hot in both senses of the word salt through pipes and pumps and such,
it might be a really difficult thing to do. Could we build one of these [INDISTINCT]
>> BONOMETTI: The Engineering challenge is--I guess, is the question pumping hot salts to
pipes and those kinds of things. We do that on a regular basis in the industry. A lot
of processes--a lot of industrial processes use the same kind of hot salt a chemical industry
uses. So, there's presidents that would pump manufactures that do that kind of thing. The
temperatures are hot but not, you know, something that's not done everyday in commercial industries.
The--obviously, the safety requirements for everything--you are talking about a nuclear
reactor, it's going have to be really good pumps and the paperwork is a mile high to
make sure those pumps are, you know, adequate. But again, even if the pump failed, it doesn't--you
can drain the tank and it will naturally get hot if the pump stops pumping. The core will
get hot over heat, pour out into your tray and stop it for you. So, if the--there's nothing
inherently that the industry can't do. It is a big systems engineering problem to make
one that's cost effective, that's safe and meets all requirements and that all the little
details were taking care of but nothing that we've seen. Yes?
>> Yeah. So, I'm guessing there's some kind of GEN-4 reactor development thing happening,
you know, a little brighter or something like this. It looks like six different designs
that they're pursuing and this is one of them but can tell us a little bit about what that
is, like what expenses get funded, how do [INDISTINCT] bigger, you know?
>> BONOMETTI: Okay. The question being, what is the GEN-4 or how does that play in with
this. GEN-4 is a department of energy initiative. It's probably a good one in some ways. They're
looking for what's the next generation reactor. Technically, malt and salt not LFTR which
is slightly different is under their category of GEN-4. My personal take on it when I look
at the amount of money they're putting in, I'm not--I'm not sure they're very serious.
I think it's--and a round of--and don't quote me, but $40,000 which is enough for one person
to go out and write a paper and go to a conference, whereas the other projects are getting much
more serious money. You know, I'll let other people decide what the track record of the
Department of Energy is in, you know, solving energy problems at this point.
>> [INDISTINCT] which is--so Kirk Sorensen had got his blog on the [INDISTINCT] so that's
one sort of [INDISTINCT] of work on this kind of thing [INDISTINCT]
>> BONOMETTI: Yes. Kirk Sorensen and I are, you know, this is our--LFTR is that. And that
thorium forum is probably the key repository in which people all get together and work
on. >> So, there was another thing in France and
then there was Per Peterson up in Berkeley working on this stuff...
>> BONOMETTI: There are several people that--you are asking who else is working thorium?
>> [INDISTINCT] still working on this stuff or he--like, results finding and then goes
to something else? >> BONOMETTI: I think he's kind of moved on
to other things. He was at the Department of the Energy, I believe and so I don't--I
don't really know the total status. Everybody's got their little ideas of how to use thorium
and some of them are just to add thorium to a reactor--the existing reactor and qualify
that fuel. Now qualification of a fuel for any reactor is a long, expensive process and
the question is if you're going to spend a lot time and money and put it into the commercial
reactors that are running fine or are safe. I would say maybe that's a little too much
money, a little risk you're doing trying to add it but that's--that is a solution for
thorium. Thorium in a pebble bed is another one that people have talked about. It's a
little bit better than maybe the conventional reactor. It's looking more and more like a
liquid system. My point is I think you should go to liquid system and burn all the fuel
because in a pebble bed or these other concepts, you don't burn all the thorium and you still
have a lot of waste that you get rid off. Yes?
>> Is this something that you [INDISTINCT] design to build through private funds or is
it something that you have to have government funding involved in them?
>> BONOMETTI: Private or government funding. Well, that's up to individuals. Again, the
organization--the [INDISTINCT] organization that I'm really representing or working with
doesn't have any answer to that. It is--it would be daunting for private funding, it
could be done for private funding. Certainly, the navy would be a prime example of wanting
something like this yet the navy has the same problem that the Department of Energy does.
They're kind of fixed in a certain pattern. It's very hard to break that. So, if somebody
wants to take it to the next step which is maybe demonstrating the chemistry without
the nuclear material, a private company would have to have some backing from the government
to say, "Yes. You can use uranium-233." Which there is actually a lot of stored and they
want to blend it down and throw it away. That's a said way the government is looking at this.
They haven't done it yet but there are plans for it. So, if I was a private company or
private funds, the first thing I'd make sure is I had somebody in the government side saying,
"Yes. We will hold that fuel. And yes, we will let you utilize that," because you need
some kind of seed--fission material in order to start the process. Okay, any other questions?
All right, one more. >> So you're not [INDISTINCT] pursuing a path
making--I mean, you're obviously making it invisible but is there a free path of, you
know, getting the government to go in on this to get research?
>> BONOMETTI: I think there are efforts that--I guess, you're question is, you know, what
are the paths that we're pursuing or the path that could be pursued to get this going other
than the education process that we're attempting to do right now? Yes, there is. There's attempt
to talk to people both in the government. When I was Naval Post graduate School, the
students that had designed projects found that it was very interesting what it could
for the navy as far as capability and ships. We need to do some more studies like that.
I suspect that is going to come out, I think in the next six months because of all the
energy research that's going to be done or analysis is going to be done just to find
out which way we want to go. The thorium will be--and LFTR specifically will be thrown in
that mix. What comes out or who stands up and says, "Yes. Let's do this," or provide
funds to do this, that remains to be seen. And I have talked to other people, you know,
privately about, you know, what specific paths we've done, you know, and share that information.
Okay. No--last minute question. One more, okay.
>> Okay. So, in considering--yes, it seems like if the problem is kind of just bureaucratic
like, you know, mindset, roadblock kind of going to the to but, you know, Obama had said
that you [INDISTINCT] anti-nuclear, go to the administration and say, "You know, what
can you do to consider this and make it, you know, maybe--you can actually take it seriously?"
>> BONOMETTI: Yes, going to the top. Again, not really a question but a statement of going
to the top all way, the administration and getting him to look at this and, you know,
point the agencies or money in that direction certainly would help. I mean, that's the easy
path if we can do that. People are working on those kinds of things. Like I said, I think
it's a credible story, enough to keep it in the mix, enough to look at it seriously and
enough to seriously look at why has it not been promulgated to this point? What are those
roadblocks and is it just, you know, the bureaucratic--bureaucracy that we have? That's a good question. Okay.
Thank you very much.