We went to CERN in Switzerland! Or was it France? It’s easy to get confused…when the border between the two countries runs right through the middle of the CERN campus!

Our perspective as a company is the industrial perspective. When we are talking to those who are generating electricity these are the things they’re worried about. An enormous wave of coal-fired power plant retirements in the United States and as you can see, this is particularly concentrated in the eastern United States where I live, particularly on the Ohio River and in the Carolinas, driven in large part by new regulations related to emissions from coal-fired power plants. You know, many people are glad we’re having these emission regulations and part of me is as well, but I’m also a little concerned of just how many gigawatts of generation capacity are being prepared to be taken off the grid in the United States.

US Renewable Options

The options for renewable energy, as you can see from the map of the U.S., are predominantly concentrated *not* in the eastern United States, so this limits our options. There is exciting activity taking place in the U.S. in the nuclear front. In Georgia, two new nuclear power plants are under construction at Vogtle site. These are going to be Vogtle 3 & 4, they’re going to be AP1000s. They’re being added to an existing site of two other pressurized water reactors, so we are going forward with new nuclear power plants under construction in the U.S.

Retirement Cliff

Unfortunately, I don’t think this is going to be quite enough because this is a graph that is already a few years old that shows how, even with renewals of licenses in the late 2020s we’re going to fall off what we call the “retirement cliff.” In other words, we’re going to be retiring reactors much more quickly than we’re bringing them online and as I said this is a few years old, this cliff has actually gotten a little worse since this graph was generated, so we need to be in position in the United States in the late 2020s to be able to add enormous amounts of generation capability to the grid quickly, and if it’s not going to be coal, what is it going to be? One of the things that I think merits consideration especially when I’m talking to an international audience is you have to understand how things work in the United States. Our Department of Energy has a very “hands-off” approach to how things should be designed and developed. In their opinion, it is the responsibility of industry to design, construct, and operate commercial nuclear power plants. It is industry’s decision which commercial technologies will be deployed. The federal government has made it explicitly clear that they don’t choose winners in the nuclear space. It’s up to industry to go and make a credible case for why technology should be developed and to go and take the risk to make that happen. They will offer some support in different ways, but it s not, from their perspective, not up to them to decide.

Modular Construction

So considering this, the needs that we’re going to have to bring new nuclear power plants online quickly, we are very interested in modular construction of nuclear reactors. And modular construction, we’ll be able to build them in a factory we’ll be able to enforce a degree of commonality and quality and uniformity to that. We’ll be able to learn quickly from mistakes rather than the way we’ve done it so many times in the past which is “in the field” construction where a lot of mistakes can get made. And we feel strongly that liquid-fluoride reactors, which are a type of molten-salt reactor, with their low-pressure operation are particularly suitable to this goal, this hope, this objective of achieving modular construction, because one of the hardest things to get around when you’re building a nuclear power plant is the large, heavy pressure vessel that’s required when use pressurized water reactors, so we see molten-salt reactor technology as a way to perhaps come closer to realizing the dream of small modular reactors. One of the first points is we don’t have to fabricate fuel.

The preparation of fuel is very easy in molten salt reactors particularly in the fluoride media. Another aspect is fission product gases are continuously removed by operation, and so that addresses one of the concerns about neutron loss to xenon; that just comes right out of solution during the operation of molten salt reactors. It is also much easier to work on the fuel in its existing form. Molten salt fuel does not have to be chemically converted to something else in order to be processed, like solid fuel does. Solid fuel, we have to turn into something else, molten-salt fuel we don’t. It’s very important to remember the merits and the benefits of molten salt and why molten salt is mentioned
so often with the thorium fuel cycle. So this is the classic design for the molten-salt reactor that came out of the Oak Ridge effort in the 1970s. It’s what we call a single-fluid reactor; all of the fuel components are mixed together in one very large unit. It’s internally moderated by graphite stringers.

Complex reprocessing

Unfortunately, as was mentioned by Dr. Rubbia, it is a rather complex reprocessing system; in order to turn this one-fluid reactor into a breeder reactor, it’s got the number of different steps in order to go and make this a reality involving the separation of that uranium from the fuel and protactinium separation, decay, and rare-earth separation, a number of things that were that were mentioned earlier today, so I will just agree that it is a complex chemical undertaking in order to go and prepare one of these reactors into a thorium breeder reactor.

Two-fluid reactor

Now previous to the one-fluid reactor work, there had been Oak Ridge studies done on what’s called the two-fluid reactor, and the two-fluid reactor is fundamentally different in that it separates the fuel, the uranium-233 fuel in FLiBe salt from a blanket material, which is also FLiBe salt carrying thorium tetrafluoride. The challenge of this two-fluid reactor design though is the internal geometry of the reactor and to keep these two fluids separate from one another. This was an Oak Ridge design for that reactor.

Simplification

The advantage, though, of keeping them separate is the simplification that can be realized in the reprocessing step and this is what I think is really worthy of consideration. Right now we have to make an economic case for why should we consider thorium as a fuel source. We can go and we can mine uranium and we can enrich it, and we can essentially burn out the small amount of uranium-235 in that, and you can put an economic quantification on the value of a gram of fissile material in the form of LEU. It’s on the order of ten to fifteen dollars out of the ground. That’s what a gram of U-235 in that fuel represents. So if you want to make an economic case for why you’re going to use the thorium fuel cycle you’d better figure out how to turn a gram of thorium into fissile and fission it for less money than that. Otherwise, despite the grand objectives of the thorium fuel cycle nobody’s really going to care from an economic basis. And so this is why we want to pursue radical simplification in the reprocessing; we want to make it as simple as we possibly can but no simpler. With the two-fluid reactor,

Fluoride Volatility

It is a rather straightforward thing to move the fuel that has been bred in the blanket out of the blanket through a fluoride volatility step and get it back into the core, which is where you want it, you want it in the core salt and this has to do with the chemical properties of uranium and thorium in fluoride media. Thorium does not have a volatile hexafluoride. You can fluorinate it and fluorinate it and fluorinate it all you want and it will not change chemical state. It will stay thorium tetrafluoride. Uranium, on the other hand, does have a volatile hexafluoride, and this is why many of us feel that the uranium-thorium fuel cycle is a perfect fit with a molten-salt reactor. This same trick doesn’t work, by the way, in uranium-plutonium fuels; they both have volatile hexafluorides, and so you can’t undergo a separation using the simple technique of fluoride volatility like you can with a thorium fuel cycle. So it’s that radical simplification that we’re pursuing.

Modular Design

This two-fluid reactor design was also designed to be modular back when Oak Ridge was working on it. In fact, they were into small modular reactors before small modular reactors were cool. These were some modern renderings we did to help us visualize their design and to understand its advantages and disadvantages a little bit better. These are two modules, two reactor cores with their heat exchangers, steam preparation system that would be connected to a steam turbine. This is not the design we are personally pursuing, but we did it as a step to help us work on our design and help us understand the geometries of this reactor better.

Internal Geometry

Inside the reactor these blue regions represent graphite channels into which the fuel salt is flowing. These green regions represent graphite channels into which just blanket salt is flowing and these black graphite structures represent the reflectors. This is to give you an idea of what the internal geometry of Oak Ridge’s two-fluid reactor design looked like.

Flibe Energy

So we formed Flibe Energy as I said to help realize this goal of designing modular, two-fluid molten salt reactors that implement the thorium fuel cycle and also a response to the way our government expects things to be done in the United States, to be industry-led, to have a business case behind it, to go and make an argument for why private investment and private industry should be interested in these technologies.

Thorium is a miracle

But our fundamental motivation is that we share the dream that was put forward by Dr. Alvin Weinberg long ago of a “world set free” by the use of thorium as a essentially unlimited energy source, and I know it was said earlier that thorium is not a miracle, to me it is a miracle. It’s a miracle that there’s a material on Earth that has such remarkable energy density that even worthless dirt is transformed into an energy resource greater than the richest crude oil or anthracite coal or any other resource you can imagine. To me, that is that is truly a miracle.

Huntsville Alabama

We’re in Huntsville, Alabama, many people don’t know much about Huntsville, Alabama. Let me introduce the the city a little bit. This is the city where Wernher von Braun and his rocket team set up shop in the 1960s. We’re the town that put man on the moon. It’s a very high-tech community. It’s also very well located within the United States; it has extensive river access to the Gulf of Mexico and to all the inland waterways of the U.S. We have a large international freight airport that has daily flights around the world carrying freight straight to Europe and connected to an extensive rail network. So we’re very well-positioned. We’re also well-positioned the fact that damaging storms and hurricanes always “peter out” by the time they get to Huntsville. So we’re protected from some of the extreme weather you might face on the Gulf.

Oak Ridge National Labs

We’re also fairly close to Oak Ridge National Labs, the birthplace of thorium and fluoride reactor technology, and the graphite reactor. That was where the first uranium-233 properties were calculated, where they realized the breeding potential of uranium-233, the first molten-salt reactor, the Aircraft Reactor Experiment, and of course the Molten-Salt Reactor Experiment which ran for almost five years and demonstrated the fundamental compatibilities of the graphite, the salt, and the Hastelloy material that contains the reactor. It was very successful; I’ve had the good pleasure of speaking with some of the gentlemen who worked on this project long ago.

Molten Salt Reactors

Because of our proximity to Oak Ridge we can move things by river, and it’s not too long of a drive and most importantly the handful of folks that actually worked on the Molten-Salt Reactor Program, they live generally in this area, and if you’ll take them to lunch or go sit on the back porch with them, they’ll tell you some stories about molten-salt reactors, and probably save you a lot of trouble and prevent you from making a lot of mistakes. So they’re nice folks, but they’re not interested in full-time work in this, and they’re not interested in any money. You know they’re, the youngest one is about 76 and the oldest one’s about 88, so they’re at a stage of life where their motivations are entirely different.

Gas Turbines

One of the things we want to do with our more modern implementation of the molten-salt reactor is to couple it to a gas turbine and this is something that was really not considered during the days of the molten-salt breeder reactor effort. They were going to couple it to a steam turbine. We think a gas turbine is the right step; there’s a number of reasons: it addresses some of the issues that we’ve been concerned about with tritium migration, but it also gives us the potential to radically reduce the form factor that would be involved in a power conversion system, and this is a chart that originally came from MIT that gives you an idea of the size reduction that you can realize going from steam, 250 megawatt steam, down to closed-cycle helium 333-megawatts, all the way down to supercritical CO2, and we’re looking with great interest in supercritical CO2. What these power systems lack, though, is a suitable heat source. These are not combustion turbines like we’re used to in gas turbines. They have to be externally heated, and that’s where a high-temperature reactor like a molten-salt reactor shows great promise. Now there was some degree of precedent for coupling a molten-salt reactor to a gas turbine. In fact, one of the original ideas was to use a molten-salt reactor to drive open-cycle air gas turbines and power a jet. So this is the crazy idea that kicked off the molten-salt reactor. So there’s just a little bit of precedent to using gas turbines. So how would our machine work? FLiBe salt carrying the uranium would pass through a core where it would be moderated by graphite. It would increase in temperature, pick up enthalpy, exit the core, pass through a primary heat exchanger where it would transfer that enthalpy to a coolant salt and this coolant salt, probably something like bare FLiBe, no actinides in it, would pass in and out of the containment boundary of the reactor. And it would heat the gas that would then drive the gas turbine, the gas turbine being a closed cycle has to be both heated and cooled, and the waste heat from the gas turbine is of suitable temperature and quality that it could be potentially used to desalinate seawater. And that’s another very exciting possibility because you go to a lot of places in the world that are interested nuclear energy, and they’re just as interested in fresh water, and they’re just as concerned about their water situation as they are about their electricity situation. So having a power conversion system that is suitable for desalination, I think, is a great advantage.

Fuel Reprocessing

Let’s talk a little bit about the fuel reprocessing because this has been a topic of some degree of controversy today; the processing that we envision between the core and the blanket is to simply run a stream of fertile blanket salt that contains a small amount of uranium-233 that has been bred into a fluoride volatility column where it is contacted with fluorine or another fluorination agent, potentially nitrogen trifluoride, and then the uranium will come out of that solution as uranium hexafluoride, as a gas. Then that gas is reduced in another column in the presence of fuel salt, UF6, and hydrogen gas and hydrogen will reduce that UF6 back to UF4, putting it back into solution and allowing it to return to the core. Now the core has been refueled by the uranium that has been generated in the blanket. The resultant of this process is HF which can then be sent to an electrolyzer and split back into the reaction components, so this is a very, very simple approach to reprocessing the blanket; it involves two steps, neither of which requires any sort of cooling time or wait time; they’re both “rad-hard” processes that can proceed immediately.

In the event that we need to quench the isotopics of the system, well, in that case, we can actually add uranium-238 if we we feel like we are about to lose physical control of the plant. That is a real option. Now on the core side, similar processes take place: you use fluoride volatility to strip off the volatile fluorides, particularly uranium. And then you go through a distillation column that will separate the uranium hexafluoride from the other volatile fluorides and then the salt which is now been stripped of the uranium goes to a vacuum distillation system. And in this system, lithium fluoride and the beryllium fluoride are boiled out of the salt leaving the fission products behind. That recycled FLiBe salt then is recombined with the uranium hexafluoride in a reduction column. Same technology as here, so these, in fact, these are actually the same unit, so use your imagination here. They’re really the the same thing, and then that salt is returned to the core so the outcome of this system is just fission product waste. We keep actinides in the reactor until they’re consumed, and that’s another very important distinction between having a liquid-fueled reactor and a solid-fueled reactor. We don’t lose material when we take it out and have to dissolve it and reprocess it. If it didn’t come out in reprocessing then it’s still in the blanket, or it’s still in the core, and we can realize a waste stream that consists entirely of fission products. We can also potentially realize very efficient approach to converting thorium into U-233 and into energy by taking this approach. These are simple steps, fluoride volatility in both cases reduction there, and then vacuum distillation. So basically three or four processes to get you a completely closed nuclear fuel cycle.

Safety

Safety is one of the most important reasons to consider very seriously molten-salt reactors, and this is because of the clever implementation that was demonstrated in the Molten-Salt Reactor Experiment of the freeze plug and the drain tank. And what this simply was, it was just a small port in the bottom of the reactor that was kept plugged by a frozen plug of salt. If all power was lost, that plug melted, the fuel drained into this drain tank and the difference between the drain tank and the reactor vessel was the reactor vessel was not meant to lose any thermal energy. The only place you wanted to lose thermal energy was to give it up in the primary heat exchanger. The drain tank, on the other hand, is designed to maximize the rejection of thermal energy to the environment. It does not have any graphite in it, so in this vessel , re-criticality is impossible. This is an important distinction when you have a thermal spectrum molten-salt reactor. A thermal-spectrum molten-salt reactor has to have the graphite moderator of the core in order to sustain criticality.

If it’s drained into that drain tank, or if the vessel ruptures and it falls into this catch pan and drains in this drain tank, re-criticality is fundamentally impossible. How do we keep the drain tank ready to go? Well, we actually use it as the decay vessel for fission product gases, so one of the processes that we need to deal with anyway keeps the drain tank in a ready state to receive the decay of fuel in case that needs to take place. So let me let me sketch out a little bit of a future here, thinking big. Here’s what we’re doing today

Nuclear Approach

with our nuclear approach, we are taking uranium and we are enriching it, and we’re essentially putting that enriched uranium in light water reactors. And when we’re done in the U.S., well, until recently we were going to go and put it in Yucca Mountain. Now that’s a little bit on hold. In the process of doing this, we’re also making plutonium, and nobody really has a good idea what to do with that yet. Our thorium stockpiles and existing U-233 inventory in the U.S. are doing nothing, they’re sitting around. If we look at what does the industry project we want to do, well, they’re interested in saying okay, let’s go and potentially reprocess light-water oxide fuel, perhaps make MOX, and then we would fuel MOX reactors using mixed oxides and that would require MOX fuel fabrication plant which we could potentially send our weapons-grade plutonium to. But in the end, everything still ends up in Yucca Mountain. Again, no mission for the thorium stockpiles and the existing uranium-233 inventory is disposed of.

What we would propose is to use many of the materials that are otherwise going to go to waste and to incorporate them into a transition to a fully thorium-powered future. We would propose taking existing nuclear waste and fluorinating it, turning it from oxides into fluorides and then separating out the bulk of it which is just essentially low-enrichment uranium and sending that somewhere where it can be disposed of and then removing plutonium and other minor actinides and using them along with existing reactor-grade plutonium, either in fast-spectrum reactors, molten-fluoride, or potentially molten-chloride, and for the liquid-fluoride reactors, the thermal spectrum reactors, we’ve proposed starting them, destroying our HEU stockpiles that way, creating new uranium-233, adding to this U-233 inventory, and then ultimately starting a fleet of liquid-fluoride thorium reactors on this fine material, this U-233 that we heard recently is the best material to start the reactor on. In this scenario, we put both our plutonium, our HEU, our U-233, all to productive use along with our thorium stockpiles.

Final Thoughts

I’ll conclude with one of my favorite quotes from Alvin Weinberg: “During my life, I have witnessed extraordinary feats of human ingenuity. “I believe that the struggling ingenuity will be equal to the task of creating the Second Nuclear Era. My only regret is that I will not be here to witness its success.”

Thank you very much for listening, and I appreciate your patience.

[Question] You separate the uranium from the thorium by the volatility. What happens to the protactinium?

[Answer] In that configuration, the protactinium doesn’t come out of the blanket until it decays to uranium-233.

[Question] So it stays in there even though it may get irradiated by more neutrons?[Answer] Yeah, one of the ways to mitigate that issue is to use a larger blanket inventory, so that the average flux that any particular amount of blanket material sees is drastically reduced. It’s pretty cheap to add more blanket fuel or even to have an external holdup of blanket fuel. That’s one way to really reduce the otherwise the losses that you would have by having a lot of flux, and that’s something you can do in molten-salt reactors, you can’t do in solid fuel reactors. You know you can reduce the realistic flux that a blanket fuel element will actually see over its lifetime.

[Question] For a private company like yours, the funding is probably a problem. Can you comment about the funding of your program?

[Answer] Yeah, we have been entirely privately funded; we’ve been incorporated now for 2 1/2 years. We have a variety of different investors in our company thus far, and are working to procure contracts that are going to allow us to go forward on this work, so small but going forward.

[Question] In America in particular, we have a nuclear regulatory agency that is sort of like a certain football coach that said that winning isn’t everything, it’s the only thing, but the NRC acts as though safety isn’t everything, it’s the only thing. Are you making any headway in making changes, and if so, what changes, what hurdles do you have in this area? And what changes would you like to see in order to make it practically feasible to get underway building things?

[Answer] A great question. We are making headway with the NRC. We have reached out to them, and they have assigned us a case number for our development activities, also made it clear that further interactions will be billed at the going rate of about $270 an hour. So it is not an inexpensive thing to begin to engage with the NRC. That being said, through informal contacts with a number of NRC personnel, they have indicated a great deal of optimism. They, you know talking to some of them privately, they’ve said you know this looks really safe. You guys have have chosen a design that eliminates many of the issues that we are concerned with from the “get-go”, and even though this is very different than a light water reactor, thus far the response from the NRC personnel we’ve talked to has been cautious optimism, and essentially saying, you know, go forward. The NRC is happy to look at anything so long as you pay their billing rate. What they won’t tell you is how long it’s going to take, and I can kind of understand that. Our job is to go and educate them on this design until they feel comfortable enough to issue a license, and that’s fair, and we understand. And, thus, that is the direction we will go. We do realize, though, that this is going to require a lot of education, this is very different than a light water reactor in every way but, sometimes, perhaps, being different isn’t all bad. If you can help them understand why this can achieve a level of safety that perhaps they’ve not been heretofore able to achieve, then.