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#601 2023-11-15 23:21:50

Calliban
Member
From: Northern England, UK
Registered: 2019-08-18
Posts: 3,796

Re: Nuclear power is safe

SpaceNut wrote:

Indirectly the rise in cost is due to fixed price for the selling of the energy.
First U.S. small nuclear reactor project canceled as costs soared
SMR project as construction costs climbed from $5.3 billion to $9.3 billion.

One has to wonder exactly how these people manage to spent $9.3bn on a 462MW glorified water boiler?  In what universe is $9.3bn good value for money for a 462MW plant?  This technology is quite old now.  There aren't really that many technological unknowns associated with light water reactors.  We have been building them in one form or another for the past 70 years.  The technology is not complicated.  There are very few moving parts involved.  The chemistry has been well understood for decades now.  We are talking about six stainless steel water boilers, each small enough to fit on the back end of a truck.  I wonder where exactly this $9.3bn is going?  How can these people spend so much on so little?


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#602 2023-11-16 07:28:03

tahanson43206
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Re: Nuclear power is safe

For Calliban re #601

These are important questions, and the person who is also a member of the forum, best qualified to dig into the matter is ** tata ** Calliban!

I am confident every monetary unit invested to this point has been squeezed from anxious investors (Including the US government) with great care, so there should be adequate documentation.  My guess is that you find that the vast majority of those funds were spent trying to retire the massive risks.  Those risks may well have been ** real ** but my guess is that a great number are imaginary, based upon lack of confidence in those who are promoters of nuclear power.

You are most certainly a proponent of nuclear power.

Unfortunately, over time, members of the elite community of which you are a part have managed to squander confidence of the public.  Now, (it appears to me) you have having to pay dearly for past over-confidence and massive mistakes, as well as countless little ones.

It is probably time for members of the elite community of which you are a part to accept the situation of earned distrust with a bit of humility.

The painful costs incurred by the backers of the NuScale project could probably have been reduced substantially, were it not for the heavy burden of past mistakes.

(th)

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#603 2023-11-23 15:07:58

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,796

Re: Nuclear power is safe

A global thorium map of the moon.
https://www.researchgate.net/figure/Top … _227001458

The richest deposits appear to be concentrated a few hundred km south of Mare Imbrium.  The white spots exceed 12ppm in concentration.  This would be a marginal deposit by Earth standards.  But rock with 13ppm Th still contains roughly 50x the mass energy density of coal if thorium is completely fissioned in some sort of breeder reactor.

The Martian surface is more difficult to survey, because the atmosphere scatters the characteristic gamma rays resulting from decay.  But concentrations there appear to be around 1ppm, which is much poorer.  In both cases, thorium and uranium would be extracted from crushed rock by nitric acid leaching.  At 12ppm, the energy density of the rock is sufficiently high that we can say with some confidence that the energy produced by fission will outweigh the energy needed to produce nitric acid for acid leach extraction.  At 1ppm, I think the case is less certain.

The Earth appears to be much richer in Th/U than any other body in the solar system.  Stony meteorites average about 0.06ppm Th.  At these concentrations it is unlikely that fissile materials woukd yield enough energy to justify extracting them, even in breeder reactors.  The Th concentration on Mars is uncertain, but appears to be on the low side.  We may need to import nuclear fuel from Earth for a long time to come.  Not that this will be very much of a problem energetically.  One tonne of uranium or thorium burned in breeder reactors, which amounts to about 1 cubic foot, would yield some 1000MW-years of electricity if all actinides fission.  So a small amount goes a very long way.

However, if the abundance present in stony meteorites is typical of minor planets, it is clear that nuclear fission is not an option for long term energy production in the outer solar system.  Any ambitions of colonising the outer planets, kuiper belt and the distant Oort cloud, are contingent on the successful harnessing of nuclear fusion.

Last edited by Calliban (2023-11-23 15:27:32)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#604 2023-11-23 17:35:08

SpaceNut
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Posts: 29,433

Re: Nuclear power is safe

repost

Mars_B4_Moon wrote:

Another thing to consider with Ore resources, Nuclear Material, Waters and Power on Mars is putting your power station reactors. The region of highest thorium content is found in the northern part of Acidalia Planitia. The region of Acidalia Planitia is a North a plain on Mars, between the Tharsis volcanic province and Arabia Terra to the north of Valles Marineris. Thorium would be an option to start building villages towns and then cities powered by Nuclear energy, it is present on Mars, but its surface concentration seems to be lower than on Earth's surface.


Nuclear energy expert sees thorium as perhaps most viable maritime future fuel
https://www.seatrade-cruise.com/environ … uture-fuel

Saves the fights to send a fueled reactor if we can do the processing on site to make a sent empty unit function for sure.

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#605 2023-11-23 23:35:18

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,796

Re: Nuclear power is safe

It is possible that Acidalia Planitia will one day be the energy hub of the Martian economy.  But unless thorium is recovered as a biproduct of other ore processing, I suspect we will be importing it from Earth for a long time to come.  A single kg of thorium would release 79.4 million MJ of energy in a breeder reactor.
https://en.m.wikipedia.org/wiki/Energy_density

That is 22 million kWh.  If it costs $1000/kg to ship thorium to Mars, it will add 0.0045 cents to the cost of each kWh of heat.  This is such a small amount that it is doubtful that it will be a priority.  Concerns about relying on Earth based powers for energy supply could motivate Martians to mine native thorium.  But Martians will depend upon Earth for so many things.

Last edited by Calliban (2023-11-23 23:44:55)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#606 2023-12-02 11:23:49

tahanson43206
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Registered: 2018-04-27
Posts: 19,443

Re: Nuclear power is safe

Here is an update on the Idaho National Labs and reactor #53 in development ...

The article concludes with mention of a reactor that might operate at one megawatt ... Now ** that ** sounds like something that would work for small towns, and for city blocks within larger ones, as well as many private industry plants, government installations and countless other users of power.

Such a reactor need not necessarily be run at full power either ... it could be run at a much lower power level to support a remote facility such as a resort or even a private home or a farm.

https://www.yahoo.com/finance/news/futu … 01640.html

Bloomberg
The Future of Nuclear Energy Will Be Decided In Idaho
Will Wade
Sat, December 2, 2023 at 8:00 AM EST·8 min read

<snip>

Many of the new reactor designs are much smaller — including some potentially as small as 1 megawatt — and are expected to be built in factories and assembled on-site. That approach may make it easier and faster to deploy the systems, and may also open the door to nuclear power entering new markets around the world. However, that also means that validating the technology will be critical, said INL’s Crone.

“The things we’re working on today are going to have a major impact on the world,” said Crone.

Apache Internal Server Error objected to something in the article quoted above.

(th)

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#607 2023-12-03 08:14:12

tahanson43206
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Re: Nuclear power is safe

Plot 0007 in My Hacienda is kbd512's nuclear power facility for Sagan City.  I asked ChatGPT to identify dependencies that Plot 0007 would have, that would need to be met by appropriate organizations in other plots.  The resulting discussion led to recognition that some services in support of a reactor are ** so ** specialized they will only be needed at the reactor.  This led to consideration of where to put the reactor, since most human activities will be underground on Mars.

User
I think you have hit upon a valuable insight!  Due to severe natural radiation levels on the surface of Mars, it is expected that all human habitation and most work areas will be located well underground.  It may may make perfect sense to locate the reactor above ground, where severe natural radiation is already present.   In that scenario, the specializations needed to support the reactor could be located in the volume underground. 
ChatGPT
Locating the reactor above ground on Mars, while keeping most of the support facilities and habitation underground, is indeed a strategic approach that leverages the unique environmental conditions of Mars. This setup would capitalize on the natural radiation environment on the surface and the protective shielding offered by subsurface structures. Here's a breakdown of how this could be structured:

Above Ground: Nuclear Reactor
Reactor Core and Primary Systems: Situated on the surface to directly handle the high radiation environment. This includes the reactor vessel, control rods, coolant systems, and primary safety systems.

Minimal Staffing: Limiting the number of personnel on the surface to essential operational staff only, equipped with protective gear and radiation monitoring devices.

Automated Operations: Utilizing advanced automation to minimize human exposure, with remote operation capabilities for routine operations and emergency handling.

Rapid Transport Systems: Implementing efficient transport means (like elevators or secure tunnels) for quick and safe access between the surface reactor site and underground facilities.

Underground: Support and Ancillary Services
Control and Monitoring Center: A secure and shielded underground control room for monitoring and managing reactor operations remotely.

Design and Engineering Offices: For ongoing reactor design improvements, simulations, and engineering support.

Training Facilities: Utilizing virtual reality and simulators for training personnel in a safe, controlled environment.

Maintenance and Technical Support: Housing equipment and staff for maintenance work, allowing them to prepare and then quickly move to the surface when needed.

Research and Development Labs: Focused on nuclear technology, safety innovations, and radiation protection research.

Medical and Health Monitoring Facilities: To regularly monitor the health of the reactor staff and provide immediate medical care if needed.

Emergency Response Unit: Specialized teams trained for rapid response to any nuclear incidents, equipped with protective gear and necessary tools.

Administrative and Regulatory Offices: For overseeing the operations, ensuring compliance with safety standards, and coordinating with other plots and Martian authorities.

By separating the high-radiation elements (the reactor itself) from the human-centric support functions, this plan mitigates the risk to personnel while taking advantage of Mars' natural conditions for reactor operation. It also creates an efficient operational structure that maximizes safety and functionality.

(th)

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#608 2023-12-03 09:22:29

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,796

Re: Nuclear power is safe

TH, why would you not just dig a pit and put the reactor core in that pit?  That way you get to use rock and soil for shielding without even having to remove it.  If you are concerned with neutron activation in tye rock and soil, then surround the core with a thin water filled tank, which can be as little as a few cm thick.  This will reflect half the neutron flux, absorb much of the remainder and thermalise most of what makes it past the tank.  Gamma radiation will be partially absorbed in the tank with whatever escapes absorbed by the rock and soil.  The gamma field will entend at least a few metres into rock.  So to catch all of it, you want the pit to be as deep as the reactor core is tall, plus about 5m.  But digging a pit of those dimensions will be a much easier job than building an above ground shield, which involves moving a lot of rock and soil.

Much will depend on the specifics of the reactor.  If we are talking about a fast breeder reactor of some kind, then most neutrons and gamma will be shielded out by the sodium and outer blanket assemblies.  So there isn't a lot of additional shielding needed.

Last edited by Calliban (2023-12-03 09:27:29)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#609 2023-12-04 12:39:32

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,796

Re: Nuclear power is safe

Can produce energy from thorium on Mars?

On Mars, thorium is present in some soils at 1ppm concentration.  I take this to mean 1 atom of thorium for every million silicon atoms.  One mole of silicon contains 6.02E23 atoms and weighs 28g.  The number of thorium atoms associated with 1 mole of silicon is 6.02E17.  A single fission yields 3E-11 joules.  I am going to assume we can harvest 90% of this.  Some will be lost as neutrinos.  So each fission yields 2.7E-11J.  The energy yielded from thorium extracted from 1 mole of silicon is therefore:

Q = 6.01E17 x 2.7E-11 = 16,254,000 joules

Martian regolith has a density of 2000kg/m3.  Lets us assume this is dominated by silicon dioxide, which has molar mass of 60.  One cubic metre of soil will contain some 33,333 mols of SiO2 and the same number of moles of Si.  If we could harvest all of the thorium in 1m3 of dirt, the potential energy yield would be 16.254 x 33,333 = 541,800MJ = 150.5MWh.

Next we need to look into acid leaching.  We need to know how much acid is needed per cubic metre of rock and its energy cost.


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#610 2023-12-04 13:47:11

tahanson43206
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Registered: 2018-04-27
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Re: Nuclear power is safe

For Calliban ... thanks for the analysis of thorium potential in the regolith of Mars in post #609

If the balance of the atoms in that cubic meter are harvested instead of discarded, there would be pure silicon and oxygen available for sale.  Both would have significant value on Mars.

If you were to allocate a portion of that 150.5MWh to delivering pure silicon and oxygen for sale, how much of that 150.5MWh would you have left for sale as power?

(th)

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#611 2023-12-04 16:24:52

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,796

Re: Nuclear power is safe

Thorium (IV) oxide will convert into soluble nitrates, by dissolving it into nitric acid in the present of flouride ions.
https://www.ipen.br/biblioteca/rel/R39145.pdf

ThO2 + 4HNO3 = Th(NO3)4 + 2H20

The flouride ions appear to function as a catalyst.  The reference discusses one part of HF for every 200 parts of HNO3.  But frankly, hydrogen flouride isn't something I would want to be in the same continent as me.  It is horribly toxic.  I wonder if a soluble flouride salt like NaF would work as well?

The amount of acid needed to dissolve the thorium will depend upon the relative reaction rates of the metal oxides in the presence of nitric acid.  There needs to be a high enough concentration to extract a large proportion of the thorium.  However, other metal ions will be converted to nitrates along with the thorium.

Last edited by Calliban (2023-12-04 16:46:32)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#612 2023-12-10 11:16:26

tahanson43206
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Re: Nuclear power is safe

The NewMars post at the link below contains text reporting on plans for a 40 Kw reactor.

I like this size and hope it becomes practical and then commercially available.  It is described as able to support 40 homes, which would match the number of homes in many small communities in rural areas in the US.

https://newmars.com/forums/viewtopic.ph … 24#p217024

(th)

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#613 2023-12-10 11:24:14

SpaceNut
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From: New Hampshire
Registered: 2004-07-22
Posts: 29,433

Re: Nuclear power is safe

Mars_B4_Moon wrote:

Nuclear power on the moon: Rolls-Royce unveils reactor mockup

https://news.yahoo.com/nuclear-power-mo … 01170.html


That one is planned for thermal rocket use, but I did see an article for Rolles Royce that was planning another such sized unit.

Small Modular Reacgtor

Micro Reactor

Mars_B4_Moon wrote:

Pentagon Awards Lockheed Martin $33.7 Million for Nuclear Spacecraft Project

https://gizmodo.com/lockheed-martin-air … 1851018036

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#614 2023-12-11 06:34:26

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,796

Re: Nuclear power is safe

The Rolls-Royce SMR is expected to generate 470MWe.  That is small compared to the 1200MWe units that Westinghouse and Toshiba are selling.  But it is not what most people would understand as being small.  This is still enough power for a city of a million people at European levels of power consumption.  It would be OK for a city on Mars, but it is oversized for a realistic base.  It also contains a lot of concrete, which makes it rather heavy.  We could redesign to eliminate the concrete.

Last edited by Calliban (2023-12-11 06:41:38)


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#615 2023-12-11 07:20:39

tahanson43206
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Re: Nuclear power is safe

For Calliban re SMR's ....

A 1 megawatt reactor that lasts 20 years between replacement cycles would serve most communities around the world.

It seems likely (to me at least) that mass production of such reactors would allow for significant cost reduction.

In light of the many disadvantages of centralized power facilities, I would ** think ** such a design would be accepted as desirable by enough potential customers to justify the development costs.

It seems to me that the winds are shifting a bit toward acceptance of nuclear fission as a way out of the end-of-fossil-fuels dilemma.

It's been a while since you last reported working on a serious reactor design.  It may be a good time to dust off the needed skills, and enter the competition for funding. 

(th)

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#616 2023-12-29 13:17:32

Mars_B4_Moon
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Registered: 2006-03-23
Posts: 9,776

Re: Nuclear power is safe

Nuclear sector set to power Indian space missions: Isro chief
https://timesofindia.com/home/science/n … 359396.cms

Simulations and checks on ground and space key to Chandrayaan-3 success: Mission Director Srikanth
https://www.thehindu.com/news/national/ … 659063.ece

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#617 2024-01-07 11:40:08

tahanson43206
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Re: Nuclear power is safe

Here's a UK update that seems a good fit for the "Nuclear is Safet" topic ...

https://www.yahoo.com/news/uk-invests-3 … 34760.html

UK invests 300 million pounds in nuclear fuel, eroding Russia's dominance of sector
Nate Ostiller
Sun, January 7, 2024 at 8:43 AM EST·1 min read
2 comments


The U.K. is investing 300 million pounds ($381 million) into the production of high-assay low-enriched uranium (HALEU) as a part of a larger bid to improve the country's self-sustainable energy resources and cut dependence on Russia, the U.K.'s Department for Energy Security and Net Zero announced on Jan. 7.

HALEU is a specialized fuel required to power most modern nuclear reactors, and it is currently only produced commercially in Russia. The U.K., along with the EU, has worked to reduce its energy dependence on Russia since the beginning of the full-scale invasion.

The U.K. reported in June 2022 that it had not imported any fossil fuels from Russia for the first time since 2000, when the data was first collected. The EU also said in October 2023 that it reduced coal imports from Russia by 90% and gas imports by 75%.

Investments into the U.K.'s domestic production of HALEU are part of a strategy to increase the share of nuclear power to 25% of the U.K.'s energy needs by 2050. As of 2022, nuclear energy accounted for 14% of total electricity supplied.

"We stood up to (Russian President Vladimir) Putin on oil and gas and financial markets, we won’t let him hold us to ransom on nuclear fuel," said Claire Coutinho, the U.K.'s Secretary of State for Energy Security and Net Zero.

"This will be critical for energy security at home and abroad and builds on Britain’s historic competitive advantages."

(th)

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#618 2024-01-07 16:36:42

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,796

Re: Nuclear power is safe

If the UK is serious about aiding the transition to Gen 4 reactors, it would restart its reprocessing programme and start producing MOX and metallic alloy fuels.  HALEU fuel isn't ideal for fast neutron reactors.  Plutonium is a much better fuel because it produces more neutrons in a fast flux.  Lots of spare neutrons are needed if we are serious about closing the fuel cycle, burning up actinide waste streams and breeding excess fuel for new reactor cores.  The UK always goes into these things half cocked.


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#619 2024-01-07 19:02:09

tahanson43206
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Re: Nuclear power is safe

For Calliban re #618  ... Does the UK have a fleet already?  I get the impression the problem the managers are facing is lack of supply for the existing fleet.  I'll bet there are two different agencies (or groups of people) in the picture ... One is (I'm guessing) responsible for keeping the existing fleet running as long as possible. The other (I have no way of knowing if this one exists) would be responsible for selecting a path forward.  Your post seems (to me at least) to be about planning for the future.

The article I quoted appears to be about keeping the existing fleet running.

Those two objectives would not be in conflict (I would think)

(th)

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#620 2024-01-11 18:23:46

Calliban
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From: Northern England, UK
Registered: 2019-08-18
Posts: 3,796

Re: Nuclear power is safe

Are nuclear power plants really that slow and expensive to build?
https://m.youtube.com/watch?v=5EsBiC9HjyQ


"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."

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#621 2024-01-27 12:19:36

SpaceNut
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#622 2024-01-27 13:44:32

tahanson43206
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Registered: 2018-04-27
Posts: 19,443

Re: Nuclear power is safe

In post #621 SpaceNut provided a link to an article about work at Princeton on fusion...

I think the article is worth someone's time, but the discovery is that a wall coating of liquid lithium will absorb protons from the plasma better that does an ordeinary wall. About 40% of the protons that escape the plasma captured, which means less heating of the wall, and less cooling of the plasma. Trying to create a layer of liquid lithium is going to be tricky, so it doesn't sound as though every fusion project on Earth is going to be adopting the idea any time soon, but it seems likely most researchers will at least start thinking about it.

(th)

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#623 2024-02-03 19:39:44

tahanson43206
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Re: Nuclear power is safe

This post is about NASA's encouragement of private nuclear fission concepts ...

https://www.msn.com/en-us/news/technolo … 43418&ei=5

Apparently this is NOT about KRUSTY ... it does (apparently) involve the Brayton Cycle (whatever that is)...

NASA's Fission Surface Power Project, a nuclear fission reactor that generates electricity, has successfully completed its initial phase, marking a significant step towards powering future Moon and Mars missions.

This futuristic project aims to develop a compact nuclear fission reactor capable of generating power for astronauts, a critical resource for long-term space exploration.

In 2022, NASA awarded $5 million contracts to three commercial partners.

Each partner was tasked with creating a comprehensive initial design, encompassing the reactor, power conversion, heat rejection, power management, distribution systems, cost estimates, and a development timeline.

Nuclear fission reactor vs. solar power
This initiative is crucial for establishing a sustainable human presence on the Moon for at least a decade.

Trudy Kortes, the program director of Technology Demonstration Missions within NASA's Space Technology Mission Directorate, emphasizes the importance of this endeavor.

Related video: Nuclear Fusion Reactor For Cleaner Energy (Dailymotion)

"A demonstration of a nuclear power source on the Moon is required to show that it is a safe, clean, reliable option," Kortes stated.

She highlighted the technical challenges posed by the lunar night and the necessity of a Sun-independent power source like this reactor for long-term exploration and scientific efforts on the Moon.

The limitations of solar power systems on the Moon are well-known, particularly in permanently shadowed regions and during the lengthy lunar nights, which last about 14-and-a-half Earth days.

In contrast, a nuclear reactor could offer continuous power in these challenging conditions, potentially unlocking new scientific and exploration possibilities.

Project requirements and flexibility
NASA's approach to this project has been notably open and flexible, allowing commercial partners to employ creative solutions.

"There was a healthy variety of approaches; they were all very unique from each other," said Lindsay Kaldon, Fission Surface Power project manager at NASA's Glenn Research Center in Cleveland. "We didn't give them a lot of requirements on purpose because we wanted them to think outside the box."

Despite this flexibility, NASA established critical specifications for the reactor: it must weigh under six metric tons, produce 40 kilowatts (kW) of electrical power -- enough for various lunar operations, and operate autonomously for a decade.

To put this in perspective, 40 kW can power an average of 33 households in the U.S.

Safety, particularly regarding radiation dose and shielding, remains a top priority. Beyond these stipulations, the partners also explored remote activation and control of the reactor, fault identification, and various fuels and configurations.

Collaborations between terrestrial nuclear companies and space experts led to a broad spectrum of innovative ideas.

Next steps towards a nuclear fission reactor

The next step involves extending the Phase 1 contracts to refine these concepts before launching Phase 2. This phase will involve selecting a final reactor design for lunar demonstration.

"We're gathering a wealth of information from our partners," Kaldon noted. "This will guide us in setting realistic, risk-averse requirements for Phase 2."

NASA plans to open solicitation for Phase 2 in 2025. The goal is to have a reactor ready for a lunar launch in the early 2030s.

The reactor will undergo a one-year demonstration on the Moon, followed by nine operational years. If successful, this technology could be adapted for use on Mars.

Parallel to this, NASA has recently awarded contracts to Rolls Royce North American Technologies, Brayton Energy, and General Electric for developing Brayton power converters.

These converters are essential for transforming the thermal power from nuclear fission into electricity. However, current models are inefficient, losing much heat.

NASA's challenge to these companies is to enhance the efficiency of Brayton converters, a crucial step towards optimizing nuclear power usage in space.

This ambitious project represents a significant leap forward in space exploration. By harnessing nuclear power, NASA aims to overcome the challenges of sustaining human life in space, paving the way for prolonged lunar stays and, eventually, human missions to Mars.

-----

I asked Bing about Brayton Power Converters ..

Space Brayton power converter units are a closed-cycle version of a gas turbine engine or aircraft auxiliary power unit (APU). Typically, an inert gas binary working fluid, usually a mixture of He and Xe, is recirculated through a compressor and turbine coupled to a rotary alternator as shown in Figure 3.
Nuclear Electric Propulsion Brayton Power Conversion Working Flu…

ntrs.nasa.gov/api/citations/20220002293/downloads/E-20018P.pdf

(th)

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#624 2024-02-03 19:47:29

tahanson43206
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Re: Nuclear power is safe

This post focus on Stirling vs Brayton cycles...

About 26,300 search results
Search results
Image courtesy of users.wpi.eduusers.wpi.edu
Dynamic power cycles can achieve conversion efficiencies of greater than 25% due to their close approximation to the ideal Carnot cycle. Generally, closed Brayton machines can achieve 40% of Carnot at cycle tem-perature ratios between 3 and 4, while free-piston Stirling machines can achieve 60% of Carnot at temperature ratios between 2 and 3.
ntrs.nasa.gov › api › citations
A Historical Review of Brayton and Stirling Power Conversion

and ...

People also ask

Do Brayton Rankine and Stirling power cycles operate in space?


What is a space Brayton converter?


Why do Brayton and Stirling cycles use a gaseous working fluid?


Why is a regenerative Rankine cycle better than a Brayton cycle?

ntrs.nasa.gov › api › citationsAn Analysis of the Strayton Engine, a Brayton and Stirling ...
– Generally greater efficiency gain for lower power generating engines because Stirling power level scales with temperature ratio, not Brayton power production. – Controls study demonstrates system sensitivity to design parameters and illustrates Stirling off design operation. 20 • Key Technologies – High temperature materials

File Size: 544KB
Author: Jeffryes W. Chapman, Donald L. Simon, Ezra O. McNichols
Page Count: 21
Publish Year: 2019
ntrs.nasa.gov › api › citationsA Historical Review of Brayton and Stirling Power Conversion ...
A Historical Review of Brayton and Stirling Power Conversion Technologies for Space Applications Lee S. Mason and Jeffrey G. Schreiber Glenn Research Center, Cleveland, Ohio November 2007 NASA STI Program . . . in Profile Since its founding, NASA has been dedicated to the advancement of aeronautics and space science.

File Size: 2MB
Author: Lee S. Mason, Jeffrey G. Schreiber
Page Count: 15
Publish Year: 2007
www.sciencedirect.com › science › articleAn evaluation of power conversion systems for land-based ...
Apr 1, 2022 · Power conversion cycles (Subcritical Steam, Supercritical Steam, Open Air Brayton, Recuperated Air Brayton, Combined Cycle, Closed Brayton Supercritical CO2 (sCO 2), and Stirling) are evaluated for land-based nuclear microreactors based on technical maturity, system efficiency, size, cost and maintainability, safety implications, and siting cons...

Author: D.P. Guillen, P.J. McDaniel
Publish Year: 2021
www.researchgate.net › publication › 237139028_AA Comparison of Brayton and Stirling Space Nuclear Power ...
Feb 1, 2001 · … Summary of Specific Mass Projections for Brayton and Stirling Power Systems … Mass Comparison of Radioisotope Power Systems for Rovers and Robotic Science. … Mass Comparison of Reactor...

If a member has time (and this is of interest) please explain why one would choose one or the other of these systems. There must be good reasons why NASA is encouraging improvement of the Brayton cycle.

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#625 2024-03-03 14:51:34

Mars_B4_Moon
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Registered: 2006-03-23
Posts: 9,776

Re: Nuclear power is safe

something triggers a 404 or filter error

China Thorium Ship
https://archive.fo/oldRt

France and EU energy council

https://archive.fo/NP4tc

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