Nuclear News Thread

[cancel2 2022]

.
Kairos and Materion commission molten salt purification plant

The plant, designed by Kairos Power and based at the Materion campus in Elmore, Ohio in the USA, will produce high-purity fluoride salt coolant to be used in high-temperature molten salt reactors.

Salt Purification Plant (Image: Kairos Power)
Kairos Power's fluoride salt-cooled high-temperature reactor (KP-FHR) is cooled by a mixture of lithium fluoride and beryllium fluoride salts known as Flibe, which is chemically stable and operates at low pressure. The molten salt coolant will be used in Karios's engineering test unit and proposed Hermes demonstration reactor as well as future commercial KP-FHR reactors.

Materion is an industry leader in the production and manufacturing of beryllium-based materials and the decision to locate the Molten Salt Purification Plant (MSPP) at its Elmore facility is said to "reinforce a long-term, strategic commitment by both companies to demonstrate leadership in molten salt production".

Ed Blandford, Chief Technology Officer and co-founder, Kairos Power, said: "We are thrilled to announce the commissioning of MSPP, a critical milestone to produce Flibe for KP-FHR technology and the cornerstone of our collaboration with Materion Corporation. MSPP represents a major investment in Kairos Power’s vertical integration strategy to achieve cost certainty by establishing commercial Flibe production. We have confidence in our ability to produce Flibe that meets our nuclear specification for Kairos Power’s testing programme at the scale necessary to supply our major hardware demonstrations."

Alan Kruizenga, senior director of salt chemistry and production at Kairos Power, said: "With MSPP we have scaled up a chemical process developed in Kairos Power’s Salt Lab to produce Flibe in large quantities with specifications that demonstrate our ability to deliver for ETU, Hermes and beyond ... we are grateful for the collaboration of the Materion team, who worked alongside us throughout the pandemic to help set up a critical manufacturing capability for Kairos Power while working through the challenges a new process and technology have associated with it."

Keith Smith, vice president of nuclear, science and government affairs at Materion, said: "The MSPP has been in design and process development for more than a year. This is the largest Flibe production facility ever built and has the capacity to generate commercial quantities of the material."

In April this year, Bruce Power, Constellation, Southern Company and Tennessee Valley Authority joined the Kairos Power Operations, Manufacturing and Development Alliance. The consortium’s goal is to advance the development of the company’s KP-FHR technology.

Kairos Power's construction permit application for the Hermes low-power demonstration reactor is currently under formal review by the US Nuclear Regulatory Commission. Hermes is a demonstration version of the Alameda, California-based company's KP-FHR, a 140 MWe fluoride salt-cooled high temperature reactor using TRISO (TRI-structural ISOtropic) fuel pebbles with the low-pressure fluoride salt coolant. It is scheduled to be operational in 2026.

https://www.world-nuclear-news.org/Articles/Kairos-and-Materion-commission-molten-salt-purific

 

[T. A. Gardner]

I am not a fan of molten salt reactors. There are a whole list of reasons you don't want to use one.

 

[cancel2 2022]

I am not a fan of molten salt reactors. There are a whole list of reasons you don't want to use one.

I think the advantages outweigh the disadvantages. Not least being they generate far less waste than conventional reactors and indeed can use spent fuel as a feed stock.

 

[T. A. Gardner]

I think the advantages outweigh the disadvantages. Not least being they generate far less waste than conventional reactors and indeed can use spent fuel as a feed stock.

No, they don't. It is very hard to operate them without minute leakage and that leads to all sorts of disasters. The molten salts are corrosive and that means far more maintenance. The benefits of compact size are outweighed by the safety and maintenance complexity of these reactors.

 

[cancel2 2022]

No, they don't. It is very hard to operate them without minute leakage and that leads to all sorts of disasters. The molten salts are corrosive and that means far more maintenance. The benefits of compact size are outweighed by the safety and maintenance complexity of these reactors.

Yes the molten salts are corrosive but the problems are well understood and new alloys are being developed to deal with it. This Quora post is well worth reading.

https://www.quora.com/How-dangerous...7&share=61c4ae3d&srid=aclK&target_type=answer

 

[McRocket]

'One of the proposed sodium-cooled fast reactors, TerraPower’s 345 megawatt Natrium, has received considerable media attention recently because TerraPower founder Bill Gates has been citing it during interviews about his new book, How to Avoid a Climate Disaster. In mid-February, Gates told 60 Minutes correspondent Anderson Cooper that the Natrium reactor will produce less nuclear waste and be safer than a conventional light-water reactor.

In fact, according to the UCS report, sodium-cooled fast reactors such as the Natrium would likely be less “uranium-efficient.” They would not reduce the amount of waste that requires long-term isolation in a geologic repository. They also could experience safety problems that are not an issue for light-water reactors. Sodium coolant, for example, can burn when exposed to air or water, and a sodium-cooled fast reactor could experience uncontrollable power increases that result in rapid core melting.

“When it comes to safety and security, sodium-cooled fast reactors and molten salt-fueled reactors are significantly worse than conventional light-water reactors,” says Dr. Lyman. “High-temperature, gas-cooled reactors may have the potential to be safer, but that remains unproven, and problems have come up during recent fuel safety tests.”'

https://www.ucsusa.org/about/news/report-advanced-nuclear-reactors-no-better-current-fleet

https://www.ucsusa.org/resources/advanced-isnt-always-better

 

[cancel2 2022]

'One of the proposed sodium-cooled fast reactors, TerraPower’s 345 megawatt Natrium, has received considerable media attention recently because TerraPower founder Bill Gates has been citing it during interviews about his new book, How to Avoid a Climate Disaster. In mid-February, Gates told 60 Minutes correspondent Anderson Cooper that the Natrium reactor will produce less nuclear waste and be safer than a conventional light-water reactor.

In fact, according to the UCS report, sodium-cooled fast reactors such as the Natrium would likely be less “uranium-efficient.” They would not reduce the amount of waste that requires long-term isolation in a geologic repository. They also could experience safety problems that are not an issue for light-water reactors. Sodium coolant, for example, can burn when exposed to air or water, and a sodium-cooled fast reactor could experience uncontrollable power increases that result in rapid core melting.

“When it comes to safety and security, sodium-cooled fast reactors and molten salt-fueled reactors are significantly worse than conventional light-water reactors,” says Dr. Lyman. “High-temperature, gas-cooled reactors may have the potential to be safer, but that remains unproven, and problems have come up during recent fuel safety tests.”'

https://www.ucsusa.org/about/news/report-advanced-nuclear-reactors-no-better-current-fleet

https://www.ucsusa.org/resources/advanced-isnt-always-better

Lyman is with the Union of Concerned Scientists who are deeply anti-nuclear, I'd take everything he says with a huge boulder of rock salt.

 

[cancel2 2022]

'One of the proposed sodium-cooled fast reactors, TerraPower’s 345 megawatt Natrium, has received considerable media attention recently because TerraPower founder Bill Gates has been citing it during interviews about his new book, How to Avoid a Climate Disaster. In mid-February, Gates told 60 Minutes correspondent Anderson Cooper that the Natrium reactor will produce less nuclear waste and be safer than a conventional light-water reactor.

In fact, according to the UCS report, sodium-cooled fast reactors such as the Natrium would likely be less “uranium-efficient.” They would not reduce the amount of waste that requires long-term isolation in a geologic repository. They also could experience safety problems that are not an issue for light-water reactors. Sodium coolant, for example, can burn when exposed to air or water, and a sodium-cooled fast reactor could experience uncontrollable power increases that result in rapid core melting.

“When it comes to safety and security, sodium-cooled fast reactors and molten salt-fueled reactors are significantly worse than conventional light-water reactors,” says Dr. Lyman. “High-temperature, gas-cooled reactors may have the potential to be safer, but that remains unproven, and problems have come up during recent fuel safety tests.”'

https://www.ucsusa.org/about/news/report-advanced-nuclear-reactors-no-better-current-fleet

https://www.ucsusa.org/resources/advanced-isnt-always-better

Read the OP more carefully!!

Kairos Power's fluoride salt-cooled high-temperature reactor (KP-FHR) is cooled by a mixture of lithium fluoride and beryllium fluoride salts known as Flibe, which is chemically stable and operates at low pressure

 

[McRocket]

I do not know if they are better or worse then other reactors.
But I have - for a few years - had a personal appreciation for lead-cooled fast reactors.

https://www.osti.gov/servlets/purl/1113427
https://en.wikipedia.org/wiki/Lead-cooled_fast_reactor
https://www.sciencedirect.com/science/article/pii/B9780081001493000069

These reactors can be entirely cooled, passively.
Thus, you could literally (apparently) leave a lead cooled fast reactor unsupervised and cut all power to it.
And it will simply cool down, all by itself.
And if the reactor is breached?
The solidifying lead should seal the opening...whilst lead offers excellent radiation protection.

Plus, it apparently is much, more energy efficient than water-cooled reactors.

I imagine there are lots of reasons it is not suitable.
But you sure can't beat it for safety...apparently.

 

[McRocket]

Lyman is with the Union of Concerned Scientists who are deeply anti-nuclear, I'd take everything he says with a huge boulder of rock salt.

This is the first I have heard of them.
But, so far, nothing I have read indicates they are in the slightest bit - 'anti-nuclear'.

And this dude who wrote the link I posted - Edwin Lyman - seems to have received lots of awards and appreciation for his expertise on various aspects of nuclear technology.

From wikipedia:

'In 2018, Lyman was awarded the 2018 Leo Szilard Lectureship Award from the American Physical Society "for using his technical expertise and tireless advocacy to maintain and strengthen U.S. policy on nuclear nonproliferation and reactor safety and security.'

https://en.wikipedia.org/wiki/Edwin_Lyman
https://www.aps.org/programs/honors/prizes/prizerecipient.cfm?last_nm=Lyman&first_nm=Edwin&year=2018

This sure doesn't sound like a guy who is 'deeply anti-nuclear' to me.

 

[McRocket]

Read the OP more carefully!!

Kairos Power's fluoride salt-cooled high-temperature reactor (KP-FHR) is cooled by a mixture of lithium fluoride and beryllium fluoride salts known as Flibe, which is chemically stable and operates at low pressure

Fair enough.
I didn't read the OP at all.
I just saw the discussion between you and TA.

However, according to this link from Oak Ridge National Laboratory?
This KP-FHR - is just another form of a salt-cooled reactor.

'MSRs fall into two classes: salt-cooled reactors, in which the core contains a solid fuel and liquid salt coolant, and salt-fueled reactors, in which the fuel is dissolved within the salt. The term “fluoride salt-cooled high-temperature reactor” (FHR) was adopted in 2010 to distinguish fluoride salt-cooled MSRs from other MSRs.'
https://www.ornl.gov/content/fluoride-salt-cooled-high-temperature-reactors

And since this Lyman guy was referring to 'salt cooled reactors'?
And, since these 'fluoride salt-cooled high-temperature reactor's' have actually been around since 2010.
Then - until I read evidence to the contrary - I am going to assume this Lyman guy is including your reactor in his overall comments.

But I could be wrong.
And your reactor seems to have lots of promise.
We shall see.


Anyway, I have no great interest in getting into some, big discussion about this.
I made my points, posted a few links and I will leave it at that.

It's an interesting subject though.
Glad you started the thread.

Good day.

 

[cancel2 2022]

'One of the proposed sodium-cooled fast reactors, TerraPower’s 345 megawatt Natrium, has received considerable media attention recently because TerraPower founder Bill Gates has been citing it during interviews about his new book, How to Avoid a Climate Disaster. In mid-February, Gates told 60 Minutes correspondent Anderson Cooper that the Natrium reactor will produce less nuclear waste and be safer than a conventional light-water reactor.

In fact, according to the UCS report, sodium-cooled fast reactors such as the Natrium would likely be less “uranium-efficient.” They would not reduce the amount of waste that requires long-term isolation in a geologic repository. They also could experience safety problems that are not an issue for light-water reactors. Sodium coolant, for example, can burn when exposed to air or water, and a sodium-cooled fast reactor could experience uncontrollable power increases that result in rapid core melting.

“When it comes to safety and security, sodium-cooled fast reactors and molten salt-fueled reactors are significantly worse than conventional light-water reactors,” says Dr. Lyman. “High-temperature, gas-cooled reactors may have the potential to be safer, but that remains unproven, and problems have come up during recent fuel safety tests.”'

https://www.ucsusa.org/about/news/report-advanced-nuclear-reactors-no-better-current-fleet

https://www.ucsusa.org/resources/advanced-isnt-always-better

I do not know if they are better or worse then other reactors.
But I have - for a few years - had a personal appreciation for lead-cooled fast reactors.

https://www.osti.gov/servlets/purl/1113427
https://en.wikipedia.org/wiki/Lead-cooled_fast_reactor
https://www.sciencedirect.com/science/article/pii/B9780081001493000069

These reactors can be entirely cooled, passively.
Thus, you could literally (apparently) leave a lead cooled fast reactor unsupervised and cut all power to it.
And it will simply cool down, all by itself.
And if the reactor is breached?
The solidifying lead should seal the opening...whilst lead offers excellent radiation protection.

Plus, it apparently is much, more energy efficient than water-cooled reactors.

I imagine there are lots of reasons it is not suitable.
But you sure can't beat it for safety...apparently.

MSRs have a plug of salt at the bottom of the reactor which is kept cool whilst in operation. Any situation causing overheating results in the plug melting and emptying into a containment vessel at the bottom of the reactor, simple and entirely automatic requiring no human intervention.

 

[Bigdog]

Read the OP more carefully!!

Kairos Power's fluoride salt-cooled high-temperature reactor (KP-FHR) is cooled by a mixture of lithium fluoride and beryllium fluoride salts known as Flibe, which is chemically stable and operates at low pressure

I have a dumb question. Why is the highly electronegative element fluoride so critical to MSR operation, if it is in a chemically stable bond.

 

[cancel2 2022]

'One of the proposed sodium-cooled fast reactors, TerraPower’s 345 megawatt Natrium, has received considerable media attention recently because TerraPower founder Bill Gates has been citing it during interviews about his new book, How to Avoid a Climate Disaster. In mid-February, Gates told 60 Minutes correspondent Anderson Cooper that the Natrium reactor will produce less nuclear waste and be safer than a conventional light-water reactor.

In fact, according to the UCS report, sodium-cooled fast reactors such as the Natrium would likely be less “uranium-efficient.” They would not reduce the amount of waste that requires long-term isolation in a geologic repository. They also could experience safety problems that are not an issue for light-water reactors. Sodium coolant, for example, can burn when exposed to air or water, and a sodium-cooled fast reactor could experience uncontrollable power increases that result in rapid core melting.

“When it comes to safety and security, sodium-cooled fast reactors and molten salt-fueled reactors are significantly worse than conventional light-water reactors,” says Dr. Lyman. “High-temperature, gas-cooled reactors may have the potential to be safer, but that remains unproven, and problems have come up during recent fuel safety tests.”'

https://www.ucsusa.org/about/news/report-advanced-nuclear-reactors-no-better-current-fleet

https://www.ucsusa.org/resources/advanced-isnt-always-better

I have a dumb question. Why is highly electronegative fluoride, if it is in a chemically stable bond, so critical to SMR operation.

Fluorine is highly reactive and thus forms extremely strong chemical bonds and highly stable metallic salts. Because of that it means corrosion is less likely than with molten sodium and its salts.

 

[T. A. Gardner]

I have a dumb question. Why is the highly electronegative element fluoride so critical to MSR operation, if it is in a chemically stable bond.

There are two reasons a particular molten (when operating) salt or metal is chosen for the moderator and coolant:

1. As a moderator, the physical properties of that atom are good for interacting (I'm trying to avoid a lot of physics terms here to keep it simple) with the neutrons produced by the nuclear reaction. This is important to making those reactions stable and ongoing.

2. As a coolant, it remains a liquid at the operating temperature and pressure. Steam (a gas) is a lot less effective at cooling the reactor unless a gas was intended to be used in the design.

You also want to use stuff (a highly technical term) that will make the reactor work worse the hotter it gets. That means if it starts to overheat, it starts to shut itself down. The Chernobyl design using graphite as a moderator and water as coolant, worked better the hotter it got. That didn't work out so well...

One of the bigger problems with these exotic salts and metals as moderator / coolant is they potentially create long-lived radioactive isotopes and that in turn creates more stuff (there's that term again!) that you have to deal long-term when you get rid of everything after the reactor is no longer in service. That means you have to be careful in choosing such materials to avoid this issue if possible.

Water is a good choice since it only takes about two months for all the isotopes created to pretty much decay to nothing. After that, you have--water...

 

[Bigdog]

Fluorine is highly reactive and thus forms extremely strong chemical bonds and highly stable metallic salts. Because of that it means corrosion is less likely than with molten sodium and its salts.

Thanks, I thought Fluorine was the main source of the corrosion issue. I would have guessed it was worse than sodium.

 

[Bigdog]

There are two reasons a particular molten (when operating) salt or metal is chosen for the moderator and coolant:

1. As a moderator, the physical properties of that atom are good for interacting (I'm trying to avoid a lot of physics terms here to keep it simple) with the neutrons produced by the nuclear reaction. This is important to making those reactions stable and ongoing.

2. As a coolant, it remains a liquid at the operating temperature and pressure. Steam (a gas) is a lot less effective at cooling the reactor unless a gas was intended to be used in the design.

You also want to use stuff (a highly technical term) that will make the reactor work worse the hotter it gets. That means if it starts to overheat, it starts to shut itself down. The Chernobyl design using graphite as a moderator and water as coolant, worked better the hotter it got. That didn't work out so well...

One of the bigger problems with these exotic salts and metals as moderator / coolant is they potentially create long-lived radioactive isotopes and that in turn creates more stuff (there's that term again!) that you have to deal long-term when you get rid of everything after the reactor is no longer in service. That means you have to be careful in choosing such materials to avoid this issue if possible.

Water is a good choice since it only takes about two months for all the isotopes created to pretty much decay to nothing. After that, you have--water...

Nice explanations.

I didn't know that about water and radioactive decay.

And some of the other Stuff

 

[Into the Night]

This will be a regular thread highlighting good news to offset the bullshit regularly spouted by scientific illiterates.

NuScale Power Signs Collaboration Agreement with the U.S. Reactor Forging Consortium

NuScale Power Signs Collaboration Agreement with the U.S. Reactor Forging Consortium
04/22/2022

This remarkable collaboration will strengthen supply chain capabilities as NuScale Power approaches commercialization

Grant secured through Commonwealth of Pennsylvania for work with Concurrent Technologies and North American Forgemasters

PORTLAND, Ore.--(BUSINESS WIRE)-- Today, NuScale Power and the U.S. Reactor Forging Consortium (RFC), comprised of North American Forgemasters (NAF), Scot Forge, and ATI Forged Products, announced they have signed a Collaboration Agreement to leverage the existing robust forging supply chain in the U.S., to prepare NuScale to deploy its small modular reactor (SMR) technology to customers worldwide and to support, retain, and expand U.S. manufacturing jobs.

The RFC is the combination of highly qualified expert suppliers of nuclear-grade forgings for the worldwide nuclear industry. The combined three companies act as the only fully integrated manufacturer of large alloy and stainless steel open die, seamless rolled ring, and large uniquely-shaped forgings (heads with integral nozzles) in the Western Hemisphere with as-forged piece weights exceeding 160 tons.

Under the Collaboration Agreement, the RFC and NuScale will cooperate in design for manufacturability reviews for forged geometries to reduce welding, chemical composition tailoring and optimized configuration for fabrication. The collaboration will support the U.S. supply chain planning as NuScale approaches near term commercialization of the NuScale Power Modules™ (NPM).

The Collaboration Agreement supports the U.S. Department of Energy’s (DOE) report released earlier this year, “America’s Strategy to Secure the Supply Chain for a Robust Clean Energy Transition,” designed to retain and develop U.S. jobs through the exploration of mutually beneficial domestic business relationships. This includes, but is not limited to, U.S. and State Government grants and funding opportunities, development of FC member company capabilities and capacities, and other U.S. manufacturing opportunities.

Consortium member NAF is currently partnering with Pennsylvania-based Center for Advanced Nuclear Manufacturing, operated by Concurrent Technologies Corporation (CTC), on a full production size shell research project that will focus on the use of austenitic stainless steel for reactor and containment vessels in SMRs and advance reactors. Financed in part by a grant from the Commonwealth of Pennsylvania, Department of Economic Development, NAF in collaboration with its joint venture owners Scot Forge and ELLWOOD Group, INC. will perform melting, forging, heat treating, rough machining, mechanical testing, and non-destructive testing while CTC oversees the development and performs independent technical evaluations of the forged material. This partnership will serve to create jobs by establishing a supply chain in Pennsylvania and ultimately benefit the overall development of SMRs and advanced reactor deployment.

The RFC partners are strategically located across the U.S. and are helping NuScale strengthen its U.S. supply chain. NAF has its principal office in New Castle, Pennsylvania; Scot Forge is headquartered in Spring Grove, Illinois; and ATI Forged Products has its office in Cudahy, Wisconsin. NAF, Scot Forge, and ATI have previously worked collaboratively on the refinement of designs and manufacturing feasibility of large nuclear grade forgings for the NPM.

About NuScale Power

NuScale Power is poised to meet the diverse energy needs of customers across the world. It has developed a new modular light water reactor nuclear power plant to supply energy for electrical generation, district heating, desalination, hydrogen production and other process heat applications. The groundbreaking NuScale Power Module™ (NPM), a small, safe, pressurized water reactor, can generate 77 MWe of electricity and can be scaled to meet customer needs. The VOYGR™-12 power plant is capable of generating 924 MWe, and NuScale also offers four-module VOYGR-4 (308 MWe) and six-module VOYGR-6 (462 MWe) plants and other configurations based on customer needs. The majority investor in NuScale is Fluor Corporation, a global engineering, procurement, and construction company with more than 70 years supporting nuclear projects.

NuScale is headquartered in Portland, Ore. and has offices in Corvallis, Ore.; Rockville, Md.; Charlotte, N.C.; Richland, Wash.; and London, UK. Follow us on Twitter: @NuScale_Power, Facebook: NuScale Power, LLC, LinkedIn: NuScale-Power, and Instagram: nuscale_power. Visit NuScale Power's website.

On December 14, 2021, NuScale announced a definitive business combination agreement with Spring Valley Acquisition Corp. (Nasdaq: SV, SVSVW). Upon the closing of the business combination, NuScale will become publicly traded under the new ticker symbol “SMR.” Additional information about the transaction can be viewed here:

https://www.nuscalepower.com/about-us/investors

One of the better things to come out of the Portland area in a while.

 

[Into the Night]

.
Modular Molten Salt Nuclear Power for Maritime Propulsion

Evolving modern modular molten salt nuclear technology incurs comparatively lower cost while using a zero-pressure reactor and lower non-weapons grade uranium fuel. A module measuring 13 feet by 23 feet using a briefcase-sized load of solid fuel weighing 440 pounds could deliver 100 MW of thermal energy for up to 25 years. This potentially cost-competitive technology has potential for future commercial ship propulsion, along with multiple stationary floating power generation applications.

Introduction

Several navies around the world operate scaled-down versions of nuclear power stations aboard ships and submarines to provide propulsion and ancillary power. The onboard nuclear reactors are cooled by high-pressure water and many (including the U.S. Navy’s reactors) require weapons-grade uranium for fuel. While such propulsion technology is suitable for a naval vessel, it has zero application in commercial civilian ship propulsion.

New developments in nuclear technology are based on an old idea involving the molten salt reactor, which can operate free from high pressure water and offer greater long-term operational safety while being suitable for mass production, reducing capital cost.

The technology uses solid non-weapons grade uranium fuel mixed into a chloride salt that melts at 750 degrees F in a pressure-free reactor. Any mixture that should ever leak out of the reactor would cool and solidify, free from any explosion. For maritime propulsion, the technology is comparable to a battery that holds sufficient charge to provide up to 25 years of propulsion at variable power settings. The carbon-free propulsion system saves many years of expense on fuel oil for transoceanic propulsion, providing the maritime industry with an economic and environmental case for its use.

Power output

The modular molten salt reactor delivers up to 100 MW of thermal energy at sufficient temperature to generate steam to activate turbines, which drive electrical generators. Unlike earlier nuclear technology that has to operate continually at constant power output, the molten salt reactor can rapidly adjust its power output and adapt to external demand. A single module could deliver between 4,000 and 26,000 horsepower in either propulsive or stationary floating generator station applications.

The generating system would run on steam power and used seawater to cool the condensers when required when operating at elevated levels of output, with potential for organic Rankine-cycle engines to convert a portion of the exhaust heat to useable power.

Many vessel operators reduce sailing speed to 12 knots to save fuel and reduce engine exhaust emissions, while others sail their ships at 18 to 24 knots. A trio of modular molten salt nuclear reactors connected to steam power conversion could provide sufficient power to sail the largest bulk carriers and the largest container ships economically at elevated speed. Slower ships could use a single molten salt reactor as a primary source of propulsion, perhaps with a back-up piston or turbine engine.

Transportation terminals

Many advances are occurring in electric battery storage technology applied to the transportation sector. This includes short-sea maritime, commercial roadway, railway and even short-haul airline propulsion. There are many locations internationally where maritime ports are located within close proximity to airports, both of which connect directly or indirectly to road and railway transportation. Future battery-electric propulsion provides opportunity to install modular molten salt reactor technology at major transportation terminals to provide energy recharge for a variety of short-sea maritime vessels, commuter aircraft, trucks, buses and even railway technology powered by any of batteries, overhead cable or third rail.

At some locations, there may be scope to use floating technology to carry several modular reactors, the result of seasonal peak traffic at some major transportation terminals. Floating technology could move internationally to spend a few weeks to a few months at locations requiring peak seasonal electric power. Land based modular reactors located next to the ocean would provide base-load power throughout the year. Modular reactors would be able to generate hydrogen for mainly aircraft propulsion, with hydrogen also being made available to some forms of maritime, railway and road vehicle propulsion.

Reusing spent fuel

Molten salt nuclear technology has the potential to reuse spent fuel from older nuclear power stations. It can do so at a very high level of safety, eliminating high-pressure water from the reactor while the molten salt material contains the radiation. Reusing reprocessed spent fuel offers a long-term cost advantage in terms of the expense of hydrocarbon oil fuel. As the fuel approaches expiration, much of it is recyclable via reprocessing while non-recyclable material would be cast in concrete and stored until full expiration after a period of about 100 years.

Conclusion

The modern modular molten salt nuclear reactor has potential to fulfill multiple applications in the maritime sector, including propulsion and floating power generation. It has the potential to power a commercial vessel for the entirety of its normal lifespan without refueling.

Power reactors don't use weapons grade uranium anyway. Nothing new there.
Making use of spent fuel is a big plus. This too has been done in some reactors that simply use what the fuel can give (since it's otherwise waste product), regardless of inefficiency. Waste products from these results in material you can put in an ordinary landfill.

The nice thing about THIS design though is the ability to use it for mobile power supplies such as marine use.

 

[Into the Night]

MIT joins a major startup backed by Bill Gates to build a viable fusion machine
The goal is to build the world's first burning plasma net energy machine.

https://interestingengineering.com/mit-bill-gates-build-fusion-machine

Fusion isn't burning anything. It is fusing two atoms into one. The goal to build a prototype fusion reactor is certainly a challenge. Such a reactor is designed to put out a single pulse of fusion, and to harness the heat from it.
Continuous fusion really isn't practical, since it would create material as hot as the Sun. No magnet or anything else would prevent such a reactor from melting (and probably a fair bit of land around it!). Fusion would instantly stop of course, but the residual heat would still dissipate into surrounding structures. There is no insulation that can withstand such abuse. The end result would probably be a steam explosion as it hit the water table.

Bill has always had a mind to help with the dream of creating a controllable fusion reactor since he heard of fusion. Practical power generation from fusion would necessarily make use of duty cycle modulation to control the radiant heat affecting the reactor structure.