I can't say what kinds of security analyses we had to do to meet regulatory requirements, because there's a host of things you have to do to even know what security requirements there are. That's not even close to publicly available, for good reason.
I can say we have to analyze to massive vehicle bombs, armed assault, etc.
Here's what the possibly interesting, counterintuitive analysis showed. If you have a plant where a massive bomb can't cause damage to exceed regulatory standards (...we are talking about a truly miniscule amount of material here in this micro fission powerhouse in comparison with the nuclear plants you are probably thinking of... literally not more than a meter tall and wide, underground, below layers and tonnage of concrete and steel) and if an armed assault can't cause damage like that either, are you doing a favor by having a host of armed people on site? Probably not, in fact. Insider risk is then too large. There you go!
(totally agree with no "move fast and break things" here. I'm about 8 years into working on this company and still see many years ahead. we wouldn't be doing anything great if we weren't bringing forward the safest emission-free power plant to reality)
You're exactly right here, and I'd say this is well put in several areas.
I'll add that supercritical CO2 sounds like science fiction to people, but it's actually been pretty well demonstrated at the small sizes. The scaling up is what needs to happen if it's used at sizes beyond a few MWe. We've worked with vendors who have these available at the <5 MWe scale.
And I'll second what you're saying about subsidy. The incredible subsidies out there, if I didn't care about fission, would make me agree with those that are effectively anti-nuclear. If those hundreds millions and billions to single companies are necessary to * ever * get a single nuclear plant built, it just doesn't add up that it will be successful without all that propping it up. I agree it isn't necessary to subsidize, and that's how we believed it was important to run our company to date.
In this case, I'll name names, and I hope this isn't taken in a malicious sense because it isn't meant that way. But I've always wondered why Bill Gates, one of the wealthiest humans on the planet, would go to Capitol Hill for money for his nuclear company. I think I've learned that it's for reasons along the lines of what you said there. Creating a self-sustaining government program goes a long way to guaranteeing that the government cares about your company, and anyone else along the trail of $. I'm not blaming that, of course it is smart, it is just intriguing what paths occur.
PS also agree on "carbfix" - that while I'm all for all solutions to climate issues, it is wild to me too how much press that carbfix gets too in comparison to at least my perception of its reality of potential. But i suspect it goes back also to a great govt relations piece...
It's a good thing then that we analyzed to such extreme events as completely losing everything above ground, whether due to an avalanche, a tornado, an earthquake, etc, etc. :) The inherent safety in the fuel type means that there would still be zero dose. (for more info on the tests that showed this result originally in historic research reactors in operation: http://www.thesciencecouncil.com/pdfs/PlentifulEnergy.pdf)
PS I realized that you thought the structure was glass. No wonder. It's not, it's steel panels. Modular construction. There are optional solar panels on the exterior, maybe that's what you saw.
At least use an image of a panel, not glass, geodesic dome then and don't try to sell it as a community meeting point. That's a more acceptable current day view on how a nuclear reactor should look. Also cut the bitcoin BS. It's like trying to associate your project with Bernie Madoff. The hardest thing is to change people's perception and radical approaches don't cut it in this case.
I edited the above comment instead of replying here (whoops). I realized that you thought the structure was glass. No wonder. It's not, it's steel panels. Modular construction. There are optional solar panels on the exterior, maybe that's what you saw. Please see the other comments on why having a heated, lighted building space is important in the communities we've gotten to know. Bitcoin isn't BS when it's a first moving customer, even while we are actively working with plenty of other customers you'll recognize well, when the time comes to announce. It takes time.
Hey Gloriana,
I'm sure PR experts would say I'm probably not making a good decision responding here, and I haven't even had anything to drink, but I'll take a stab at sharing a bit on each of your points. I hope this response will be taken in the good faith in which it is given.
1) There's certainly many hundreds of pages/slides in the fully public docket on the NRC website, but the easiest source for the most information in one place is our application itself: bit.ly/AuroraCOLA. I don't expect anyone to want to read that entire thing either, but it's there. The only main things that are withheld are generally either: export controlled (defined by the Department of Energy, and we take it seriously) which includes detailed core maps, or security-related information (defined by the NRC). But the rest of it is all there. If there's something you want to know that isn't there, I'm happy to respond.
2) We are building our designs off the 30 years of experience and data with EBR-II and other fast reactors (http://www.thesciencecouncil.com/pdfs/PlentifulEnergy.pdf). EBR-II was ended prematurely for political reasons and had plenty of life left. The EBR-II showed how electricity could be put on the grid with higher uptimes than even the commercial fleet at the time. Unfortunately, I can't give details, but let's just say other major developers of historical fast reactors didn't release their economics because they didn't want it to cannibalize their other plants. But you don't need to believe that either. Our business model is to provide power via PPA so if the economics don't work for the customer we simply won't have a deal. Our FOAK plants are economic already in remote or higher cost areas, but the real key to our economics is when we are able to recycle existing waste, a fact unique to fast reactors.
3) 1% was really to be conservative for the FOAK, to try to make the licensing of the FOAK simpler within the datasets we had. I assume you know a number of SFRs have worked toward establishing datasets for up to and beyond 15% burnup. I really don't know where the number of 100 MT of uranium comes from. We would have <5MT total of fuel for 20 years, with <1T of that being uranium. 1.5MWex24hrx350days/yrx20 years is something like 250 GWe?
4) Oof. Yes, fast reactors can consume the fuel from today's reactors, and even though that supply chain isn't established, the FOAK is using waste fuel from EBR-II. I can assure you it is not pristine. No one else wants it. :) But we are working together with the DOE on a project with Argonne National Lab to begin work on the recycling from today's reactors (https://www.energy.gov/articles/doe-announces-over-65-millio...).
5) Hm. well, I want to be positive here: I'd argue there's a difference between our first customer announcement being Compass and a TEDx with my alma mater, and moving forward for years with something that fellow students and professors said had fundamental issues since grad school, which a professor finally leaked to the press out of frustration (and yes, we might have been fellow students). It's funny, I always said we should never do a TED too because they seem so smarmy, but a friend at my undergrad and the students there were organizing a TEDx and honestly it was cute and was just a fun opportunity to go back there for various reasons. We've been working with other more traditional customers in ways that we can't announce yet. But, we are working with other customers you'll likely approve of more. Remote communities as well as big companies just truly do need reliable power and they do want it to be emission-free.
6. They did seem to go out of their way didn't they. More will come on this once we are able to put out our own account too after 30 days, just because we should have the opportunity to set the record as well. But, to put myself in their shoes, they are trying to defend against an appeal or legal action. Neither of which we really have interest in, we just want to try again, move forward.
7. I responded to this with Paul. TL;DR: I don't think an attractive and functional building with all required security and operational characteristics means we are "down playing the seriousness." If you've been out to these truly poor, remote communities in the Arctic circle as I have, you'll see why they care about having heated, lighted, indoor areas in the long winters. And when the analysis shows the safety and security required, why wouldn't we offer that to them?
Well, there you go. Feel free to pick it apart but hopefully it added some context to the press releases and pretty pictures and whatnot.
I had previously gone though the Oklo COLA, which is indeed hundreds of pages. But quantity is not always quality. I have seen the same types of submissions from other reactor proponents, and they are far more detailed, comprehensive, and informative and they are mostly at earlier stages of NRC engagement in pre-application discussions. As an example, I can't find a basic dimensioned or labeled reactor drawing or system diagram in Oklo's COLA. As far as the COLA illustrates, the Aurora design consists of an A-Frame drawing and a cylindrical vessel in a dugout. The safety analysis provided are generally simplified, rarely showing uncertainties or limitations of the analysis. See the NuScale or GE-Hitachi designs in pre-application or even the Transformational Challenge Reactor (TCR) as an example of a well documented research thrust that has not even begun the regulatory process if it ever will: https://tcr.ornl.gov/publications/
As far as spent fuel goes, the EBR II fuel that Oklo plans to use took decades to reprocess at a cost much greater than 0, which Oklo is not paying for. EBR II is not a civilian power generating reactor like all LWRs and BWRs currently in operation. Perhaps one day, reprocessing spent fuel will be cost effective. But today, it is a totally unnecessary activity as there's plenty of uranium and spent fuel storage is not an issue. I think telling congress that Aurora will consume spent fuel from today's reactors is false and disingenuous, both because it is extremely expensive to do so and because it is not particularly useful.
Aurora is ostensibly a tiny fast reactor, though I have to guess at this as there are no dimensioned figures in the COLA. Neutron leakage is going to be big and burnup low. This might be why Aurora is limited to 1% burnup. Maybe Oklo plans to make much larger reactors in the future, which have very different safety characteristics but can achieve higher burnup. It's curious that of the 70+ reactors in development, there are no fast spectrum and tiny reactors except for Oklo. There are fast reactors like TerraPower Natrium but they 200x larger than Aurora.
The calculation for tons / GWe-yr is as below assuming a 33% efficient power cycle (reasonable given the low temperatures of the heat pipes, but maybe the sCO2 is really good). GWe-yr is a unit of energy.
1.5 MWe * 20 yr means you are producing 4.5 MWth for 20 years, and must have fissioned 35 kg of Uranium (you get 200 MeV per U fission which is 2.6 MWyr / kg U). If 1% burnup is assumed, as indicated, Aurora is using 3500 kg or 3.5 tons of HALEU. I think this would change a bit depending on the spectrum.
Thanks for the followup as well. I'll just respond on a couple of the points:
- you don't see these detailed core schematics with analyses because in our design they are designated export controlled (ECI) as I mentioned. It doesn't mean that they aren't in there or that they haven't been extensively performed and documented.
- the endeavor (and cost) of downblending EBR-II fuel over many years has been based on the national and state nonproliferation agreements to downblend this high enriched used fuel from EBR-II. Don't confuse that endeavor with processing used, low-enriched fuel from existing plants. In the one case, the downblending work was being performed for many years in the interest of downblending before storing as waste (except now, instead, it can be used to produce clean power and demonstrate a FOAK fission plant). In the other case, recycling existing waste, we are already working with DOE (and starting NRC interactions) about deploying recycling existing nuclear waste for fuel. I can tell you it's incredibly cost effective for a fast reactor to utilize the TRU in existing low-enriched waste and that is our goal for not just feel-good reasons but also for economic reasons. It is not false nor disingenuous.
It's true that the burnup is far less than would be ultimately most economically efficient. The FOAK was intended to serve as a bit of an MVP as I already mentioned. But it's key that larger doesn't mean less safety. The fundamentals of the safety in this case lie in how the fuel has inherent shutdown characteristics, which were proven true of EBR-II (at 65 MWth) even as it's true of Aurora (<10MWth). Many different plants have different mechanisms of safety at various size ranges!
Thanks for engaging and your thoughtful responses.
Fair point, but when we examined just having everything underground, it was more expensive actually. Once you consider operational realities in a remote environment (especially in permafrost), it is beneficial to have power conversion equipment indoors, offices, a bathroom, storage areas, etc. and then you're talking a building above ground anyway. There is security protection built in too that I can't elaborate on.
It would seem that both could be possible, but you're the expert here. ;) We didn't have to spend much time or money on an actually nice looking design, and the a-frame has a lot of practicalities I'm happy to talk about more (modular construction, resilience against snow, useful angle for the solar panels, strength for the internal cranes). (and yes, the power generating equipment, offices, and other space, is inside)
I guess then again here I am as part of the leadership engaging in communicating with the HN community on a friday night and hopefully transparently answering questions. I guess I can't help myself! I do think the public needs to both learn about the realities of fission, and I don't think it has to be ugly.
> I guess then again here I am as part of the leadership engaging in communicating with the HN community on a friday night and hopefully transparently answering questions.
Are you trying to guilt trip people by showing your dedication? It's in your own interest to do this, if you don't feel like it go and watch TV or something and don't bother. "Here I am on a Saturday morning commenting on HN etc..."
Haha not really. :) I was pretty much laughing at myself, responding to the commenter's idea that Oklo leadership shouldn't be spending cycles on building parameters with architects (i did - it's arguably important on a number of levels - security, regulatory, cost/finance/constructability, human factors, community relations etc...) but here i am spending cycles on like HN comments instead of other work which of course we do all weekend anyway.
It's a good conjecture, Paul. One might assume that low probability events were a major issue. With a design that is first of a kind, and given that the proven inherent safety characteristics, Oklo could analyze to the most extreme events (as you know, EBR-II showed how this fuel type, with no flowing coolant, and no shutdown systems, would inherently shut itself down http://www.thesciencecouncil.com/pdfs/PlentifulEnergy.pdf).
In this case, that meant assuming that everything above ground was completely gone. The building, the secondary side (power conversion equipment etc), and all human intervention, were all assumed gone. On top of that, Oklo analyzed the simultaneous loss of one of 3 independent shutdown systems. This is obviously a much higher bar than any existing nuclear plant, and for good reason: our mission is to build a new kind of plant with these inherent safety characteristics.
There might be a reason why there wasn't a lot of detail on sodium fires - there is no pool of sodium. The heat pipes use potassium. :) Oklo did tests on what happens in air, if sodium heat pipes were fully breached with huge holes and interacted directly with air. I was there. We just straight up had incredible amounts of energy hitting the heat pipe from myriad solar mirrors. It was pretty fun to test advanced fission with solar thermal. Anyway, there was a little bit of smoke, and actually the heat pipes kept functioning far longer than even the heat pipe expert expected, because the reacted sodium kept self-cauterizing the hole. In this reactor's case, the heat pipes would be in an inert environment, but it was interesting to see what would happen if somehow it were just pulverized in an open outdoor field.
There are roughly 40 external events that had to be analyzed: earthquakes, wind, tornadoes, seiche, avalanches, landslides, wildfires, you get the idea. What happens in our methods was that the worst possible event was analyzed. We took seismic accelerations worse than ever recorded in the history of the entire united states. It turns out, with a thorough risk analysis (based on risk analysis standards set up in the history of EBR-II and PRISM and others), that assuming you lose literally everything above ground is about the most conservative thing that is within the realm of happening once every million years. Keep in mind we were just seeking a 20 year license for a plant smaller than the MIT research reactor, but low-enriched.
But the end result is as you say, we have learned, they've learned, and we resubmit. We believe deeply that if fission is going to make a difference a commercial plant has to be built before the end of the decade! Happy to answer any questions.
NuScale will, after about 15 years of engagement, receive a design certification later in 2022. After that- they will still need to apply with a combined license application like Oklo did.
I can say we have to analyze to massive vehicle bombs, armed assault, etc.
Here's what the possibly interesting, counterintuitive analysis showed. If you have a plant where a massive bomb can't cause damage to exceed regulatory standards (...we are talking about a truly miniscule amount of material here in this micro fission powerhouse in comparison with the nuclear plants you are probably thinking of... literally not more than a meter tall and wide, underground, below layers and tonnage of concrete and steel) and if an armed assault can't cause damage like that either, are you doing a favor by having a host of armed people on site? Probably not, in fact. Insider risk is then too large. There you go!
(totally agree with no "move fast and break things" here. I'm about 8 years into working on this company and still see many years ahead. we wouldn't be doing anything great if we weren't bringing forward the safest emission-free power plant to reality)