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Muon catalysed fusion.
https://en.m.wikipedia.org/wiki/Muon-catalyzed_fusion
This method appears just capable of reaching breakeven under the right conditions. Not a promising approach for energy production on its own. However, assuming a deuterium tritium mix is used, it would generate a lot of high energy neutrons. These neutrons could then fast fission a depleted Uranium or Thorium blanket generating a substantial net energy gain. Initially, each 13MeV neutron would fission a 238U nucleus, releasing 200MeV of energy, releasing over a dozen times more energy than the fusion reaction alone. The fission events will release secondary neutrons, some of which will breed 239Pu or 233U in the blanket and some of which will breed tritium in the lithium coolant.
I wonder if such a reactor could provide a solution for the enormous power needs of a growing Martian base, estimated to be around 100kW per capita. Mars does possess Thorium and using superfact 13MeV fusion neutrons, allows us to skip the breeding stage and fast fission the Thorium directly. This has numerous advantages.
Last edited by Calliban (2022-03-09 19:17:45)
"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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I do wish they'd stop chasing tokamaks. They've been studied for over fifty years and we still don't have even breakeven. What other approaches are being starved of funding because of it? And if we decided instead to focus on inexpensive neutron sources (for subcritical reactors and burning fission waste) we would probably take different approaches as well.
The Migma design seems to have been abandoned pretty quickly, without even trying the easier D-T and D-D reactions. I wonder if it has promise as a neutron generator?
"I'm gonna die surrounded by the biggest idiots in the galaxy." - If this forum was a Mars Colony
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Terraformer, my thoughts exactly. The Tokamak will never be an economic powerplant even if the much hoped for goal of breakeven is reached. But other approaches could be used to build hybrid reactors very soon. The world is facing shortages of enriched Uranium, but there is no shortage of DU tailings or Thorium. With a fusion neutron source, these resources become fuels. We don't even have to worry about the long doubling times that limit breeder reactors. In a fast breeder reactor, it can take decades to double the initial fuel load, which has to be highly enriched. It is the neutrons that are fast, not the breeding.
"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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All my life fusion energy has been 20 years away. That covers the working life of most senior people in the field, so they can claim their full pension!
I do wish they'd stop chasing tokamaks. They've been studied for over fifty years and we still don't have even breakeven. What other approaches are being starved of funding because of it? And if we decided instead to focus on inexpensive neutron sources (for subcritical reactors and burning fission waste) we would probably take different approaches as well.
The Migma design seems to have been abandoned pretty quickly, without even trying the easier D-T and D-D reactions. I wonder if it has promise as a neutron generator?
Let's Go to Mars...Google on: Fast Track to Mars blogspot.com
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Having Fusion Reactors on Mars might no longer be a science fiction story of the far future?
https://interestingengineering.com/nucl … sma-record
'A nuclear fusion device pushes plasma to a record-breaking 100 million degrees'
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NASA funds nuclear power systems for possible use on the moon
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Major Breakthrough Puts Dream of Unlimited, Clean Nuclear Fusion Energy Within Reach
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Nuclear Fusion At 100: The Hidden Race For Energy Supremacy
https://hackaday.com/2020/01/23/nuclear … supremacy/
It’s hardly a secret that nuclear fusion has had a rough time when it comes to its image in the media: the miracle power source that is always ‘just ten years away’. Even if no self-respecting physicist would ever make such a statement, the arrival of commercial nuclear fusion power cannot come quickly enough for many. With the promise of virtually endless, clean energy with no waste, it does truly sound like something from a science-fiction story.
China to nurture "fusion talent"
https://www.iter.org/newsline/187/823
Why nuclear fusion is gaining steam – again
https://www.thestreet.com/phildavis/new … team-again
Last edited by Mars_B4_Moon (2022-07-01 18:16:37)
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Smaller, stronger magnets could improve fusion devices
https://www.spacedaily.com/reports/Smal … s_999.html
Researchers at the U.S. Department of Energy's (DOE) Princeton Plasma Physics Laboratory (PPPL) have found a way to build powerful magnets smaller than before, aiding the design and construction of machines that could help the world harness the power of the sun to create electricity without producing greenhouse gases that contribute to climate change.
The scientists found a way to build high-temperature superconducting magnets that are made of material that conducts electricity with little or no resistance at temperatures warmer than before. Such powerful magnets would more easily fit within the tight space inside spherical tokamaks, which are shaped more like a cored apple than the doughnut-like shape of conventional tokamaks, and are being explored as a possible design for future fusion power plants.
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Nuclear fusion: Ignition confirmed in an experiment for the first time
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https://www.newscientist.com/article/23 … irst-time/
Last edited by Mars_B4_Moon (2022-08-12 11:02:50)
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Korean nuclear fusion reactor achieves 100 million°C for 30 seconds
https://www.shiningscience.com/2022/09/ … ieves.html
The JET nuclear fusion project spells an exciting future
https://interestingengineering.com/scie … on-project
ITER project: how are cranes helping to build a new sun?
https://www.khl.com/news/iter-project-h … 27.article
Scientists Demonstrate Technique to Protect Fusion Devices from Sudden Energy Loss
https://nz.finance.yahoo.com/news/scien … 00158.html
Why Nuclear Power Is (Quietly) Making a Big Comeback All Around the World
https://fee.org/articles/why-nuclear-po … the-world/
Nuclear Fusion Is Doing the Impossible—Uniting Politicians
https://www.newsweek.com/nuclear-fusion … mp-1736423
Last edited by Mars_B4_Moon (2022-09-07 13:32:13)
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China unveils plans for combined fusion-fission reactor
https://www.scmp.com/news/china/science … er-6-years
Chinese researchers will try to create a nuclear fusion reaction by using the strong electric charge to ignite a small number of hydrogen isotopes deuterium and tritium. And in a departure from previous designs, the fusion energy produced by the Chinese facility will not go to the power grid, but drive a swamp of superfast particles to hit uranium – the fuel which will power the facility’s fission component.
The Z-FFR reactor is expected to be completed around 2025 in Chengdu, Sichuan province in southwest China.
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China unveils plans for combined fusion-fission reactor
https://www.scmp.com/news/china/science … er-6-yearsChinese researchers will try to create a nuclear fusion reaction by using the strong electric charge to ignite a small number of hydrogen isotopes deuterium and tritium. And in a departure from previous designs, the fusion energy produced by the Chinese facility will not go to the power grid, but drive a swamp of superfast particles to hit uranium – the fuel which will power the facility’s fission component.
The Z-FFR reactor is expected to be completed around 2025 in Chengdu, Sichuan province in southwest China.
This sounds like a fusion-fission hybrid reactor. The advantage of this concept is that the super-fast neutrons released by fusion will fast-fission virtually any actinide isotope. These reactors can extract 100% of the theoretical energy content of uranium, compared to light water reactors which are limited to <1%. The fuel does not need reprocessing and such a reactor coukd even be fuelled by actinide nuclear wastes.
"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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Would the final waste materials be relatively safe?
Done.
Done.
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Would the final waste materials be relatively safe?
Done.
No. The spent fuel would be mixed actinides, containing something like 20% fission products. Definitely not safe, but produced in small quantities compared to LWR spent fuel. If the fuel were subject to pyro-processing, fission products could be seperated by dissolving them in cadmium. The actinides would be cast into new fuel. The fission products woukd be highly radioactive, but this radioactivity would decline to about the same level as natural uranium ores after a few centuries. So a hybrid reactor with a closed fuel cycle solves the nuclear waste problem. Instead of needing a repository that traps waste for a million years, a few hundred years would do. It is easy to design and build waste stores for centuries of containment. Geology need not come into it. We can build reinforced concrete buildings that last that long. When you need to contain something for a thousand centuries, the job is much tougher.
"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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China Discovers Mineral on the Moon That Could be Used for Nuclear Fusion
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U.S. Government Offers $50 Million Reward for Private Nuclear Fusion Firms
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Something works ...maybe...Beam Target Fusion Solid State Fusion... Deuterium and titanium samples and Problems muon catalyzed fusion?
https://www.youtube.com/watch?v=ZbzcYQVrTxQ
Old article 2013
China Focus | Fusion: a pipe dream for China's energy craving?
https://chinafocus.ucsd.edu/2013/10/26/ … y-craving/
Scientists, why not simply invent a working fusion plant using $50m from Uncle Sam
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The problems with achieving near term fusion power are not technological, they are political. Western scientists could have built an inertial confinement fusion reactor decades ago. There is just one catch. Whilst lasers or ion beams can achieve the density increase and hot spot temperature needed for ignition, they cannot do both simultaneously. It is much easier to compress the fuel than it is to heat it. So IC experiments usually find it easy to generate the pellet compression needed, harder to generate the required temperature rise and impossible to do both at the same time.
The thing is they never needed to. A few micrograms of fissile actinide isotope at the centre of each pellet would provide hot spot heating precisely when the pellet reaches critical density. Using a fissile trigger would make IC fusion technologically easy. The reason this has never been done is that western politics and scientific circles alike, insist on treating all nuclear fission technologies as if they were dipped in shit. The drive for 'pure' nuclear fusion is ideologically driven and it has kept nuclear fusion far away from realistic practicality for fifty years now.
Plenty of other fusion technologies, like muon catalysed fusion, lattice confinement fusion, piezoelectric fusion, electrostatic confinement fusion, etc, are all completely impractical as stand alone power sources. But they would work fine as neutron sources driving fission reactions. In the case of lattice confinement fusion, fission neutrons are the energy source that drives the fusion reactions. LCF would be a superb neutron multiplier in a fission reactor. It could lead to a whole new era of fission reactors, with economic and safety benefits that are presently beyond reach of pure fission reactors. But LCF becomes entirely useless as a stand alone energy source, because the energy needed to accelerate deuterons exceeds the net energy yield, most of which is released as pesky neutron radiation.
So long as the political and scientific communities continue to treat fission as a lepper technology, don't expect to see much progress in the achievement of fusion as an energy source. And any start up or industry consortium attempting to build a hybrid reactor that used fission in the smallest way, would have to wait about twenty years to get their experimental reactor approved by the NRC, or ONR or whatever other tedious bureaucracy happens to exist in their country of origin. They would litteraly grow old and reach retirement as these agencies twiddled their thumbs and wasted the decades away.
Last edited by Calliban (2022-10-09 16:21:24)
"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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This paper presents the Chinese design fusion-fission hybrid.
https://www-pub.iaea.org/MTCD/Meetings/ … _p3-21.pdf
A fusion reaction produces fast neutrons which fast-fission the surrounding uranium blanket. These reactors will generate power and their spent fuel will contain sufficient plutonium for several downstream fission reactors.
During the high growth phase of a Martian colony, a hybrid would allow Martians to rapidly increase nuclear capacity by breeding fissile fuel from native Martian uranium.
Last edited by Calliban (2022-10-26 04:28:57)
"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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Advancing fusion energy: Researchers achieve record-breaking temperatures in a tokamak
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US Announces $46 Million In Funds To Eight Nuclear Fusion Companies
https://hardware.slashdot.org/story/23/ … -companies
The US Department of Energy has announced that eight American companies working on nuclear fusion energy will receive $46 million in government funding to pursue pilot plants aimed at generating power from fusion reactions. Reuters reports:
The Energy Department's Milestone-Based Fusion Development Program hopes to help develop pilot-scale demonstration of fusion within a decade. "The Biden-Harris Administration is committed to partnering with innovative researchers and companies across the country to take fusion energy past the lab and toward the grid," Energy Secretary Jennifer Granholm said in a release. The awardees are: Commonwealth Fusion Systems, Focused Energy Inc, Princeton Stellarators Inc, Realta Fusion Inc, Tokamak Energy Inc, Type One Energy Group, Xcimer Energy Inc, and Zap Energy Inc
The funding, which comes from the Energy Act of 2020, is for the first 18 months. Projects may last up to five years, with future funding contingent on congressional appropriations and progress from the companies in meeting milestones.
Looking to launch fusion plants that use lasers or magnets, private companies and government labs spent $500 million on their supply chains last year, according to a Fusion Industry Association (FIA) survey. They plan to spend about $7 billion by the time their first plants come online, and potentially trillions of dollars mainly on high-grade steel, concrete and superconducting wire in a mature industry, estimated to be sometime between 2035 and 2050, the survey said.
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UK Nuclear Fusion company announces space rocket US Partnership
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China plans to drill the moon for minerals, say space chiefs
https://www.thetimes.co.uk/article/chin … -92nlrwt7f
Japan investments, Large Helical Device a fusion research device in Toki, Gifu, Japan, belonging to the National Institute for Fusion Science, the second largest superconducting stellarator in the world, after the Wendelstein 7-X in Germany
https://web.archive.org/web/20111015200 … ifs.ac.jp/
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This abstract hints at the possibility of pion production with very hot plasma (T>1E11K) in massive stars.
https://www.nature.com/articles/223725a0
This got me thinking. Could ultrahot plasma one day be an economically attractive source of pions, which subsequently decay into muons?
Negative pions are produced when protons collide with low Z ions at energy >600MeV. Fission fragments have energy of ~100MeV each. A magnetically confined fission heated plasma could therefore have average particle energy in the 10s MeV range. Plasma thermalises due to internal collisions. This creates a distribution of particle energies, some of which will greatly exceed average particle energy. A composite plasma of protium, deuterium, uranium and fission products, should create many collisions in the energy range expected to generate pions.
"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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