I assume this report indicates progress toward new reactor designs.
How far are these models from commercial scale power plants? Scaled up models. More testing. Licensing. Financing More construction.
Would you guess 10 years?
To repeat from my previous post…
“Criticality proves the physics; power operations prove the engineering,” Valar said. “Power operations require cooling, instrumentation, controls, advanced shielding, and power conversion to function together as a complete system. Ward 250 went critical with those systems integrated and in place.”
Based on this, it sounds like the Valar reactor is already configured for power production. They will need to perform some extensive low power physics tests, to make sure the reactor core performs as the computer models predict. Plus, they will need to thoroughly check out the heat removal and safety systems, to ensure passive safety. For such a small reactor that uses TRISO fuel, that shouldn’t be a problem. But it sounds to me like they might be producing electricity within the next several months. We shall see.
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From the first post in this thread, the Antares reactor is evidently a low power test reactor. However, from the linked article, Antares expects to have a power producing reactor in 2027. Whether or not that happens is a question, but that is their timeline.
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Other, somewhat larger projects, are currently in construction with completion dates of 2028 to 2031 or so.
Siemens Energy of Germany is building a steam turbine and associated auxiliary systems for Oklo’s Aurora plant. Target for start up is 2028.
Kairos Power is currently building its Hermes-2 plant in Tennessee. Target date is 2030 for completion.
TerraPower is currently in construction on the Kemmerer Natrium plant in Wyoming, also with a start up date of 2030 or 2031.
I fully expect there to be delays and problems arising for most or all of these first-of-a-kind projects. That’s the way engineering works for things that haven’t been done before. TerraPower’s plans to incorporate a molten salt heat storage system into their design, in particular, sounds a little risky to me. The sodium cooling for that plant is also something that could create some start up and operational problems. We don’t have a huge amount of experience with molten sodium cooling for commercial nuclear plants in the US. As you know, elemental sodium is a rather chemically reactive, perhaps even dangerous substance if it comes into contact with water.
The new reactor designs using molten fluoride salts are also something new, and the chemical interactions with the materials coming into contact with those salts will need to be thoroughly understood. I’m not sure they have that sort of knowledge base yet. But, again, that’s how engineering works.
It will be an interesting future for nuclear power in the next few years.
_ Pete
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A third microreactor recently started up to meet the July 4 criticality target as part of the DOE Pilot Reactor program. This one is from Deployable Energy.
From the link:
The Unity microreactor is envisaged by Deployable Energy as a compact, 1 MWe water-moderated, gas-cooled “nuclear battery” designed to provide reliable, carbon-free power where conventional energy infrastructure is unavailable, impractical, or vulnerable. It says the technology aims to support a wide range of applications, including remote communities, emergency response operations, defence missions, critical infrastructure resilience, and industrial energy needs.
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First start up: Antares Nuclear, June 4
Second: Valar Atomics, June 18
Third: Deployable Energy, July 2
It will be interesting to see which of these, if any, will be the first to generate electricity. Oklo is still building its first Aurora plant in Idaho, which I believe will be a real power plant.
_ Pete
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Just to be complete on this, a fourth microreactor barely made the July 4 arbitrary DOE deadline for criticality. This one was the Aalo Atomics Critical Test Reactor.
“Our CTR went from groundbreaking to a sustained chain reaction in less than eight months - one of the fastest reactor builds in 80 years - and our company has gone from founding to fission in less than three years,” Aalo said. "The CTR includes a full-scale core, demonstrating the nuclear components of our 10 MWe reactors, which will be deployed in 50 MWe Aalo Pods to power AI data centres.
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From the Aalo website, the Aalo reactor is molten sodium cooled and graphite moderated. This seems like a strange combination. Usually, you would use sodium cooling if you want to operate in the fast neutron spectrum and burn more of the common U-238 for fuel. But such a reactor operates at low pressure, so maybe that is why they want the sodium coolant. A 50 MWe Aalo power plant will consist of five, 10 MWe reactors. They are specifically targeting AI data centers as customers.
_ Pete
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Somewhat counter intuitively, it is actually the opposite for a couple reasons. The first reason is nuclear power is very expensive. So you need to run it 24/7 to make as much money as possible, and even then stand alone nuclear power is not cost effective in the United States. If you are only running at 70% of capacity or something it is a total non-starter.
But the emphasis is on “stand alone.” The second reason is if you have carbon free nuclear supplying all or most of the baseload, then you need less solar, wind, and battery backup. This is especially important on the edge cases where, for example it is hot (therefore high demand) but the wind isn’t blowing. To accommodate that you’d need lots of extra solar and batteries that won’t get used most of the time. So some analysts think adding nuclear will make the whole system cheaper.
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And we still have the nuclear waste disposal problem. Not making much progress. Probably due to political conflict/ grid lock.
Still have the problem that wind and solar are intermittent. Hence must invest in backup systems.
Clearly we should be developing geothermal. Seems to attract little effort.
I don’t think there is a magic bullet. For example, geothermal won’t work in AZ. We’re not tectonically active anymore (all our volcanoes are extinct). Solar works better here since we have over 300 days per year of sunshine. Of course, we also have intense heat which makes the panels less efficient. I think Iceland uses geothermal to great success.
We’re also making progress on dealing with nuclear waste. Surprisingly, one promising approach is using a specific bacteria that appears to render the waste into inert minerals. Not sure of all the details of how that works (not a biologist). But, evidently, it does.
There are some pretty exciting developments in geothermal. Traditionally, there has been a very limited number of suitable locations, basically where there is hot water near the surface. But new technology potentially allows development in a much larger number of locations. Essentially, they frack hot rock formations and inject water in a closed loop system. One advantage of this method is that it is dispatchable. Dispatchable clean energy is the holy grail. Because again, it makes the whole system cheaper.
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Mixed waste maybe. There’s nothing you can do to speed up nuclear decay.
True. I’m not sure how the bacteria do it. As I said, not a biologist. I found an NSF paper (older), and a few others. This article seems to be pretty accessible, and recent. I shouldn’t have used “inert”, though. They say it forms a “stable” compound, FeU(V)O4.
There are ways to speed up the decay of spent nuclear fuel. You could burn the actinides in another reactor. This greatly reduces the time the spent fuel is a radiological problem.
Graph from here.
Spent fuel waste consists of two broad categories of materials; fission products and heavy actinides. Those transuranic actinides are things like plutonium, neptunium, and americium, plus the unburned uranium (which isn’t really a radiological hazard). A molten salt reactor, such as the LFTR, could effectively consume (transmute) those actinides. As seen in the figure above, the fission products decay away relatively quickly, after around 600 years or so. Six hundred years is a much easier timeframe to work with than the 100,000 years or more that some people talk about.
From wikipedia on the LFTR:
When these two benefits of lower transuranic production, and recycling, are combined, a thorium fuel cycle reduces the production of transuranic wastes by more than a thousand-fold compared to a conventional once-through uranium-fueled light water reactor. The only significant long-lived waste is the uranium fuel itself, but this can be used indefinitely by recycling, always generating electricity.
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Spent fuel waste is not a technical problem. There are multiple solutions. All you have to do is choose one, and stick to the plan. We had a plan with Yucca Mountain, but certain politicians decided to play political football.
_ Pete
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The volcanoes in the Cascade mountains in the Pacific Northwest are active. Mt St Helens exploded. Mt Hood is active.
I think most active geothermal operations are in eastern California. Those sites in the PNW also have cheap, abundant hydropower. Making investment in geothermal less attractive for now. Maybe one day. PNW does have Columbia River and abundant water.