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There are quite a few interesting aspects about this project. I'll try to summarize as I remember.

The reactor uses molten salt to cool the core. Unlike conventional reactors the generated heat is not pumped directly into a heat exchanger to generate steam, but is instead pumped into a storage tank. The same tank can then be accessed from outside the nuclear building, which they claim, allows them to build the whole power station component to industrial standards rather than nuclear power plant standards, which is a cost saving.

The more interesting aspect of the molten salt storage tank is that it is effective a huge battery. It can be used to ramp up the power to meet demand without having to touch the core. This means that such nuclear power plants could work well in conjunction with intermittent energy sources (wind, solar, ...etc) without the need for a gas peaker plant. In the past a big problem with nuclear was that it was an all or nothing option, as people thought it was not compatible with other kinds of energy sources due to its inability to react quickly to meet demand. This is very promising.




IIRC (correct me if I'm wrong) the other benefit of molten salt cores is that they are self regulating. They stop reacting as the heat rises, and reaction accelerates as temperature decreases. Therefore things like catastrophic meltdowns are not really a huge issue and cooling is much less of a touchy endeavor.

Also, they aren't pressurized like traditional cores are. Therefore if there was a rupture, a bunch of radioactive material doesn't go flying all over the place.

I remember looking into this a number of years ago and I'm excited to see all of the work come to some sort of mainstream fruition.


> IIRC (correct me if I'm wrong) the other benefit of molten salt cores is that they are self regulating

The feature is called a negative temperature coefficient of reactivity. Most (all?) water-moderated cores have this feature.

> Therefore things like catastrophic meltdowns are not really a huge issue and cooling is much less of a touchy endeavor.

Meltdowns such as in Fukushima and Three Mile Island are a result of reactor decay heat. In both cases, the fission has already stopped, but the shortest-lived fission products are generating enough heat to cause a problem. Pretty much every Gen-IV concept reactor has provided for passive decay heat removal as well.


So are LWRs. With MSRs one doesn't get a runaway nuclear reaction like it happened at Chernobyl and no hydrogen explosions (it doesn't use water as a coolant) like it happened at Fukushima. Also the fuel doesn't ignite in contact with water, like in sodium cooled reactors. The reactor vessel doesnt need to be pressurized, which is a huge safety advantage. Fortunately there are no also issues with spent fuel pools? One thing to watch out for is that the molten salt tank doesn't rupture or leak. Flourine based molten salts are quite corrosive.


> One thing to watch out for is that the molten salt tank doesn't rupture or leak

Yeah, from reading [0] this seems like to be a big thing to kill even CSP projects.

> Flourine based molten salts are quite corrosive.

Seems like they are going with "Molten Chloride Fast Reactor "[1] which I have no idea what kind of eutectic mixture will make this up (can't find anything besides marketing), maybe its something similar to what I was exploring back in early 2019 with various ionic chlorides with alkali earth metals [2].

[0] https://www.solarpaces.org/wp-content/uploads/Concentrating-...

[1] https://www.terrapower.com/our-work/molten-chloride-fast-rea...

[2] https://gist.github.com/cinquemb/015f8b0775db2381513f0e20186...


I don't think that's a feature of molten salt specifically? I though this was also achieved with pebble bed reactors via doppler-spreading on neutron velocities?


All true, except I think this is a uranium-fuelled reactor, but cooled with NaCl. This is different to molten salt cores, where in fact the fuel itself is a molten salt.

Both very cool technologies, if they work out.


same as these guys: https://usnc.com/mmr-energy-system/

Molten salt storage buffer like in concentrated solar.


They lost me at "hexagonal graphite blocks". All graphite moderated reactors have issues with the moderator cracking. Pebble bed is fine since the pebbles get replenished.


All kinds of companies do the same thing, Moltex Energy, Terrestrial Energy as well. Its clearly the way to go for nuclear, otherwise you can't compete against intermittent.


Nuclear is one of the easiest to regulate power sources available, better even than gas from what I remember. It is hands down the best option save red tape.


Not sure, but IIRC the last I saw from Moltex Energy also had some mention of intermediate heat storage, for similar reasons.


Is this thorium or uranium?


Thorium it’s just marketing hype. Reactor design matters more than fuel type for things like safety. People get fired up about the large supply of thorium but the fuel is not what drives the high cost of nuclear power.


As a side note, because the common argument for thorium is proliferation, you can do similar things with uranium. Not all uranium cycles will lead to weapon productions (IIRC MIT did a study and found no significant correlation between power generating countries and respective nuclear arsenals). You also can of course do Megatons to Megawatts[0] which is a far more efficient method for dismantling or retiring your nuclear arsenal. Just factors to consider that I don't think many are aware of.

[0] https://en.wikipedia.org/wiki/Megatons_to_Megawatts_Program


Well, my POV was different.

Thorium is what India has in abundance. And we're growing to be the largest consumer of energy in the world (as is China).


It’s abundant everywhere


Overall you are correct.

The only major thing Thorium has that Uranium doesn't is the ability to do a thermal breeder, thanks the Thorium cycle releasing 2.1 neutrons.

If you are not doing thermal breeder uranium is better at most things.


Thoroum gets converted to U233 in the reactor. It's esentially a breeder reactor. It helps with non proliferation somewhat because U232 is also a side product of the Thorium cycle and it's highly gamma radioactive, preventing tampering with the fuel. Which also makes it more dangerous in case of leaks and environment contamination, because it would kill anything around it and also fry electronic circuits, thus preventing cleanup with robots.


Uranium




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