[HN Gopher] Nuclear Power at McMurdo Station, Antarctica
___________________________________________________________________
Nuclear Power at McMurdo Station, Antarctica
Author : aww_dang
Score : 199 points
Date : 2021-06-18 12:05 UTC (10 hours ago)
(HTM) web link (large.stanford.edu)
(TXT) w3m dump (large.stanford.edu)
| mattr47 wrote:
| We have been running small nuclear reactors for decades now on
| USN carriers and submarines with an incredible safety record.
| mattr47 wrote:
| Icebreakers are included in this as well. Wow.
|
| https://world-nuclear.org/information-library/non-power-nucl...
| nickelpro wrote:
| Yes, but they're far less cost efficient than diesel. That's
| why the nuclear cruisers were retired. For the carriers and
| especially the subs the nuclear plants provide operational
| capacity that diesel can't match. For a research station that's
| not a concern.
| ComputerGuru wrote:
| Because the "cost of diesel" doesn't factor in any
| externalities whatsoever, of which there are many.
| nickelpro wrote:
| Of course, but those externalities are for more
| expensive/less cost efficient when discussing uranium and
| nuclear power than anything involving diesel. Personnel
| training, fuel production, equipment maintenance, pick an
| angle to inspect and you'll find the nuclear solution is
| far more expensive than traditional power plants.
| Manuel_D wrote:
| Cost of operation isn't an externality. Externalities are
| costs we don't directly pay for, like carbon emissions
| causing global warming. Fossil fuels have incalculably
| higher externalities in this regard.
| ComputerGuru wrote:
| You are talking about direct costs that _are_ priced in,
| and I actually disagree about including personnel and
| training costs in this specific instance because they are
| all - to an extent - fungible in the military or navy, as
| there is no shortage of souls and people will be trained
| for _something_ for some duration of time.
| ncmncm wrote:
| "Incredible" is exactly the right word.
|
| We have only non-classified information to suggest their safety
| record is spotless. Considering the experiences on Antarctica
| and Greenland with naval-inspired designs, an entire lack of
| reported failures really indicates lack of reports, not lack of
| failures.
| slipframe wrote:
| When it comes to reactor accidents, there is a limit to what
| can be covered up. And nuclear accidents from other branches
| of the military are publicly known; particularly, the US Army
| blew up a test reactor (SL-1), the USAF has lost some nuclear
| bombs. Either the USN is uniquely effective at covering up
| their fuckups, or they really do have an exemplary safety
| record. My money is on the later.
| ncmncm wrote:
| Losing an actual bomb is quite a lot different from having
| and fixing a coolant leak.
|
| An exemplary safety record accommodates quite a large
| number of adequately-contained failures.
| beders wrote:
| "While reactor accidents have not sunk any U.S. Navy ships or
| submarines, two nuclear-powered submarines, USS Thresher and
| USS Scorpion were lost at sea. The condition of these reactors
| has not been publicly released"
|
| And
|
| https://apnews.com/article/559da885ca7c3f6252d67e400e92a846
|
| So not exactly an "incredible" safety record, more like an
| incredibly secret record.
| ArcturianDeath wrote:
| Nothing about the 33 Million Year Old Octagon and the dead aliens
| as the real reason they are there
| ncmncm wrote:
| This project was a disaster, no matter how you slice it. It is
| very lucky that it failed only as much as it did. That it was
| down so much of the time made it worse than useless: expensive to
| build, expensive to operate, expensive to maintain, ruinously
| expensive to clean up after, and didn't even provide reliable
| baseload power.
|
| The experience does not suggest that small-format nukes are
| simpler to operate and maintain than big ones.
|
| There is no plausible scenario where small-format nukes are a
| better investment than a solar + wind + storage system,
| terrestrially. On Mars or the moon, leaks might not matter so
| much, although the catastrophic failure likely to follow would
| leave users without power.
|
| Even with insolation on Mars much reduced, solar remains the
| overwhelmingly better choice by any measure.
|
| On the moon, dark for two weeks at a stretch calls for more
| clever engineering. An 11,000 km equatorial superconducting
| transmission line with distributed solar panels could power quite
| a lot of activity. Even a 5500 km system would be immediately
| useful, given a vertically-oriented array at each end. But solar
| and storage would probably be cheaper. A flywheel constructed
| above-ground, hundreds of meters across (dumbell style, at first)
| would store quite a lot of energy. Structure could be just a
| cable on top of a tower; when stopped, the counterweights hang
| vertically, and swing out as it spins up.
|
| https://caseyhandmer.wordpress.com/2021/04/25/powering-the-l...
| Xophmeister wrote:
| I believe the USSR installed nuclear reactors in unmanned
| lighthouses along its remote northern coast. I don't know if
| that's as far north as McMurdo station is south. I also suppose,
| with them being unmanned, they may have had less strict safety
| requirements.
| jackdeansmith wrote:
| Those are RTGs that harvest a couple hundred watts of decay
| heat for really remote applications. Often used in space
| probes, etc... Bit of a different safety profile since they're
| low power and generally don't have any moving parts.
| lightgreen wrote:
| > since they're low power and generally don't have any moving
| parts
|
| Rather since they don't have a critical mass/configuration
| which makes them impossible to explode.
| MurMan wrote:
| I was a nuclear power plant operator on a submarine during this
| period. Wanting another challenge (young & crazy ...), I applied
| for duty at McMurdo Station in 1971. My request was not approved
| and I was told that the Navy had a shortage of qualified
| submarine nuc's. Sounds like the Navy had already decided to
| decommission it.
|
| I've always regretted not going to Antarctica, but this article
| makes me think that I dodged a bullet. This plant was a
| maintenance nightmare. Plus, operating a reactor with a mix of
| personnel sounds bad. We certainly had our personnel issues on
| subs, but at least all of us in Engineering had the shared
| experiences of nuclear power school, prototype training, and sub
| qualification.
| [deleted]
| TameAntelope wrote:
| That's amazing and specific experience, very cool!
|
| One thing I noticed at the top of the article was that they
| used the steam as a source of fresh water as well, did subs do
| this too, when you worked on them?
| nielsbot wrote:
| You might find this series from Smarter Every Day
| interesting. https://www.youtube.com/watch?v=g3Ud6mHdhlQ I
| didn't find a bit about how they make drinking water, but
| here's an episode about how they regenerate their oxygen on a
| nuclear sub.
| MurMan wrote:
| Yes. Subs use low-pressure steam to desalinate sea water.
| Having lots of fresh water for showers was a huge benefit of
| nuc boats over diesel boats.
| Zenst wrote:
| Handy, also for oxygen production. Did you ever have to
| light the candle?
| MurMan wrote:
| Oxygen generators use electricity (electrolysis), not
| steam.
|
| Thankfully, we never had to use oxygen candles. Candles
| are effective only in a small closed space. That would
| have been a serious emergency.
| Zenst wrote:
| Ah yes, was referring to the excess drinking water aspect
| knowing electrolysis upon sea water will produce chlorine
| due to the salt, which really would be an emergency in
| itself.
|
| Glad to hear you didn't have a situation to use one and
| does seem a very rare situation, but neat that there is a
| solid backup.
| qrybam wrote:
| For anyone else wondering what "light the candle" means
| in this context:
|
| https://en.m.wikipedia.org/wiki/Chemical_oxygen_generator
| Zenst wrote:
| If you want too see one in action:
| https://www.youtube.com/watch?v=g3Ud6mHdhlQ around 10:19
| onwards shows the candle being put into action.
| stainforth wrote:
| Every 2 hours in 2 parts of the ship? That seems like a
| lot of labor.
| jshmrsn wrote:
| I knew exactly what video you were going to link :) I
| love when the internet feels small for a moment.
| throwawaybutwhy wrote:
| How many times did you get to talk with Rickover? And yes,
| thank you for your service.
| MurMan wrote:
| Just once, briefly when he did an inspection of our boat in
| Guam. My last memory of him was standing next to the ladder
| as he left. His pants raised as his ankle reached my eye
| level exposing a leg that was smaller than my wrist. To me,
| this was a perfect example of Rickover: a giant in many
| respects, but small and petty in others.
| seanf wrote:
| https://en.wikipedia.org/wiki/Hyman_G._Rickover Fascinating
| read, sounds like Robert Moses of the Navy
| cturner wrote:
| Interesting people come to hacker news. (I'd give another
| upvote for your username if I could.) What is the essential set
| of skills/foundation knowledge for a nuclear power plant
| operator of the sort that you get on a submarine?
|
| What do you think of the submarine systems that were designed
| for you to interact with? Context - I have been thinking
| recently about submarines and wondering how crew size could be
| reduced through automation. (I am aware that a lot of work went
| into this on the Independence class ships, but my working
| assumption is that this was let down by poor structuring of the
| design team, rather than that automation is a fundamentally bad
| idea)
|
| Did you have to manage boredom when you were on-shift but did
| not have much to do? Or is there plenty to do? Or are you
| allowed to study when there is not much in the way of active
| responsibilities?
| krisoft wrote:
| > I have been thinking recently about submarines and
| wondering how crew size could be reduced through automation.
|
| I believe the Alfa class submarines went this exact route.
| According to Sutton it had a crew complement of 32:
| http://www.hisutton.com/Alfa_Class_Submarine.html
|
| Much more modern plans along similar design thinking is the
| SHELF reactor. It is designed to operates in an underwater,
| sealed capsule that is monitored and controlled remotely.
| Source: https://aris.iaea.org/Publications/smr-status-
| sep-2012.pdf
| MurMan wrote:
| You're right about HN. Experts in all domains.
|
| My experience is from the Vietnam era and doesn't apply
| today. I was drafted mid-way through an EE program when I got
| behind in units. Virtually all of us had similar backgrounds.
| The Navy had a knack for teaching nuclear physics & math to
| bright people with a high school education.
|
| The S5W plant that I operated had virtually no automation.
| Just safety interlocks and a few automatic shutdowns.
| Everything was analog. The electrical controls used mag-amps:
| dumb and inefficient, but reliable as hell. Safety was
| achieved by detailed operating procedures and highly trained
| crews. We studied and drilled constantly. Most over-qualified
| group of people I've known.
|
| There's no way that I could describe what it was like at sea
| in a few lines here. It might make for an interesting HN
| thread as there are other nuc's here. :-)
| tnorthcutt wrote:
| I for one would enjoy reading such a thread!
|
| You might enjoy Destin Sandlin's recent series of videos
| made on board a nuclear submarine: https://www.youtube.com/
| playlist?list=PLjHf9jaFs8XWoGULb2HQR...
| [deleted]
| siliconunit wrote:
| When one considers the whole loop from incredibly polluting
| mining to disposing and keeping everything decontaminated in the
| process, fission nuclear should only be seen as a last resort
| option, as much as I see the great progress that has been made of
| course. I would have gone geothermal in Antarctica... with modern
| super depth drilling tech, and hot water as side effect, looks
| like a promising choice.
| gedy wrote:
| > When one considers the whole loop from incredibly polluting
| mining to disposing and keeping everything decontaminated in
| the process
|
| You could make the same comment about modern battery tech and
| solar though.
| Accujack wrote:
| Update your knowledge of nuclear power. Mining can be done
| cleanly or not at all, and nuclear power plants generate very
| little waste - most of the waste that exists is from bomb
| making.
|
| Newer fission tech has a lot of promise... if people who are
| convinced they already know all about nuclear energy can be
| troubled to learn about it.
| ncmncm wrote:
| What we know about it is that it is the most expensive
| alternative. Building, operating, and maintaining a new solar
| installation is cheaper than just operating and maintaining a
| nuke steam generator, ignoring the huge construction and
| decommissioning costs.
|
| We finally got the ramshackle Indian Point and Diablo Canyon
| contraptions shut down, after decades of constant effort, and
| now it will cost a billion dollars and a decade or two to
| take them apart.
| beders wrote:
| Update your knowledge of nuclear power.
|
| The economics don't pan out. The opportunity costs alone are
| staggering.
|
| https://www.leonardodicaprio.org/the-7-reasons-why-
| nuclear-e...
|
| https://web.stanford.edu/group/efmh/jacobson/Articles/I/Nucl.
| ..
| roywiggins wrote:
| We have enough "waste" nuclear material that could be burned
| again in advanced reactors that mining doesn't _have_ to be a
| thing if we really got our act together.
|
| Also, the question really is about carbon emissions vs other
| types of environmental impact. Batteries and solar panels
| require great gobs of mining infrastructure too.
| wumpus wrote:
| Here's an early example of a low-maintenance low-crew small
| reactor: http://large.stanford.edu/courses/2017/ph241/berrios1/
| eigenhombre wrote:
| I deployed to South Pole ten times from 1997 to 2011, each time
| passing through McMurdo both southbound and northbound. Of course
| I knew about the reactor, and walked around that area several
| times, but it is fascinating now to read a more detailed history.
| Especially fascinating is the notion that the reactor had to fit
| in an LC-130, in order to be used at the Pole. I definitely would
| have been less than excited to be at the Pole if that reactor had
| been the main power source. (Not sure how jazzed I would have
| been to be a passenger on said LC-130, either.)
|
| That being said, I wonder if some of the compact reactor designs
| being generated today[1] would actually wind up being a good fit
| for remote sites like the Pole. The current power plant runs on
| AN8 jet fuel and spews smoke/steam into the air 24/7. Clean power
| generation there is difficult because of lack of consistent wind
| and sun energy (pilot programs were in place at various times
| when I was there).
|
| Parenthetically, the Pole's Clean Air facility there has some of
| the cleanest air in the world (upwind of the power plant). Their
| continuous CO2 measurements, graphed prominently on one wall when
| I visited, were sobering indeed to contemplate.
|
| [1] e.g., https://news.ycombinator.com/item?id=27133196 [2]
| https://cdiac.ess-dive.lbl.gov/trends/co2/graphics/South_Pol...
| wpietri wrote:
| This reminds me of a lot of technology work. "It seemed like a
| really promising idea, but when we got into it the practical
| details made it not very practical." I'll leave it to others to
| name examples, but there are reasons I'm a member:
| http://boringtechnology.club/
| Clewza313 wrote:
| There's been talk of shipping a nuclear reactor to power a base
| on Mars. The Antarctic experience indicates pretty clearly that
| from a reliability point of view, we're almost certainly better
| off with solar panels, wind turbines and batteries.
| tyingq wrote:
| Is an experience with a reactor designed and built in the very
| early 1960's really relevant? Would you also use experiences
| with early solar cells to vet out their viability today?
| elsonrodriguez wrote:
| From a reliability point of view, you're better off with
| constant power to keep humans alive, instead of fluctuating
| power that can cause humans to die.
| merpnderp wrote:
| Wind turbines? We're going to ship 30 meter blades to Mars so
| we can barely power a microwave and a few lightbulbs? A 1MW
| installation in a good location on Earth will average ~300kW.
| On Mars that will likely be 1% because of the air density
| difference, or 3kW.
| nicoburns wrote:
| And this is one if many, many reasons why Mars is and always
| will be orders of magnitude harder to habitate than earth.
| xyzzyz wrote:
| Solar power on Mars would also give you around half the
| energy you get on Earth, per unit area. It's basically like
| running solar panels on earth well beyond Arctic circle.
| [deleted]
| ncmncm wrote:
| Given the different conditions, you would use a different
| design on Mars: probably a no-moving-parts ion-release
| system.
| slipframe wrote:
| There simply isn't much energy in that wind, no matter how
| you plan to harvest it. It's like trying to get water from
| a stone (possible, but you won't get much.)
| ncmncm wrote:
| You just need to process a great deal more of it. But
| there is no upper limit to the size of an ionizing grid,
| and the mass is negligible.
| mncharity wrote:
| > On Mars that will likely be 1% because of the air density
| difference,
|
| Power goes as v^3, so a few x wind speed compensates for
| density. There are design sketches for a couple of kW at 10
| m/s, ~10 kW at 25 m/s. Getting those speeds does require
| prioritizing it in site selection. IIRC, turbine mass is
| competitive with solar under dust storms.
|
| I'd link to recent work, but sci-hub doesn't have it. :/
| godelski wrote:
| 30m sounds small. Also, not only is the atmosphere thinner,
| but sand particles are 4x smaller. Have fun repairing those
| moving parts with that erosion.
| andyxor wrote:
| Are you talking about the Kilopower project
| https://en.wikipedia.org/wiki/Kilopower
|
| it's completely different design from conventional "pressurized
| water" reactors with drastically reduced complexity, using heat
| pipes and solid core, it's more like a battery really, and
| we've been sending nuclear batteries to space for many decades
| londons_explore wrote:
| Nuclear power requires serious amounts of cooling...
|
| Without easy-access to water and evaporative cooling on Mars, I
| can imagine you'd be needing super big radiators pointing at
| the sky to make even modest amounts of electrical power. Solar
| might work out better...
| robbiep wrote:
| No, it indicates exactly nothing. You're talking about 1970e
| technology (ie when the computing power on Apollo was roughly a
| pocket calculator) vs how we will actually get there, a period
| during which nuclear reactor designs have also evolved, and the
| navy in particular has learned a huge amount.
|
| How does one article on the third portable reactor built tell
| us clearly anything at all about how we should power a
| hypothetical Mars base more than 60 years later
| Clewza313 wrote:
| We've made great leaps in safety measures since then. I'm not
| convinced we've made much in the way of progress in terms of
| miniaturization, simplicity or cost of operation though, as
| you can see from the ludicrous cost overruns seen for
| basically all recent reactors.
| Manuel_D wrote:
| Miniaturization is not desirable for nuclear power because
| of regulation. Each nuclear power plant is required to pay
| 375 million dollars in insurance, regardless of size. So
| this incentivizes building plants as large as possible.
|
| Even without regulation, things like surface area to volume
| ratio still make larger reactors more efficient.
| nipponese wrote:
| I feel like nuclear power is the only tech that people perceive
| to be static in development. Isn't it like saying we should
| have stopped using computers in the 40s because they were big,
| expensive, slow, and we're only frequently used to kill people?
| Gravityloss wrote:
| Nuclear power was great until 1986. Then it was bad. Then it
| was getting a bit better until 2011. Then it was bad again.
| Now it's a getting bit better again.
| andredz wrote:
| Why? Could you source your statement? Not that I'm doubting
| you, but I would like to learn more. :)
| gnulinux wrote:
| Fukushima nuclear disaster in 2011 was among the worst
| nuclear disasters in history; not only because its human
| toll was so high, but also because it was the "final
| straw" -- so to say -- in public opinion in Western
| countries that made people scared of nuclear energy.
| Nuclear energy remains the safest, cleanest way to
| produce energy but Chernobyl and Fukushima significantly
| reduced the funding going into this kind of research,
| because public opinion was very much against nuclear
| power. It is getting better recently, but if history
| shows anything in the next 20 to 30 years we will have
| another disaster that will change public opinion again.
| beerandt wrote:
| >not only because its human toll was so high
|
| 1 radiation death and 18 injuries? (Only 2 of which
| involved possible radiation exposure.)
|
| The "overly-conservative" decision to evacuate such a
| large area killed more people than if they hadn't
| evacuated at all.
|
| Even Chernobyl only killed ~30 people, with maybe another
| 30 cases of cancer that workers had since then.
| gnulinux wrote:
| Sorry I phrased it wrong. I meant to say "not because".
| That "only" is extraneous.
| imagine99 wrote:
| 1986: https://en.wikipedia.org/wiki/Chernobyl_disaster#Nu
| clear_deb...
|
| 2011: https://en.wikipedia.org/wiki/Fukushima_Daiichi_nuc
| lear_disa... and in the aftermath for example
| https://en.wikipedia.org/wiki/Nuclear_power_phase-
| out#German...
| saganus wrote:
| It's a reference to the Chernobyl disaster in 1986 and
| Fukushima in 2011
| grayfaced wrote:
| 1986 is chernobyl, 2011 is fukushima. His comment isn't
| on safety, but perception of safety.
| Accujack wrote:
| ...and up until today, we're still using reactor technology
| from 70 years ago.
| fastball wrote:
| Which to me indicates that it is a fantastic technology
| if they're still around after 70 years.
|
| Nobody is building new reactors with 70 year old designs
| though.
| DannyB2 wrote:
| You forgot about 1979.
| enkid wrote:
| Are wind turbines really viable with Mars's atmosphere?
| qayxc wrote:
| Let's do a simple calculation, shall we?
|
| Wind power is calculated by A * v3 * r * e
|
| A is the area, e.g. p/2 * r2 for horizontal axis designs, r
| is the air density and e is the total system efficiency
| (limited to <59% and safe to assume to be >0.4 for modern
| systems) and v is the wind speed.
|
| Mars' atmosphere is about 1% of Earth's atmosphere in
| density. Given a wind speed of 7 m/s2 (the optimal wind speed
| for most modern wind turbines), on Mars we'd get only 1% of
| the power we'd get on Earth.
|
| A 100m installation (~2.6MW on Earth) would deliver only 21kW
| on Mars. The average wind speed during a year is slightly
| higher on Mars, though, at 10 m/s2 [0]. The average power
| output thus would be about 61kW.
|
| The most important time, however, would be dust storms, which
| render solar useless. Wind speeds have been recorded to
| exceed 30 m/s2 during dust storms. Assuming we can
| efficiently shield the generator from the dust, the power
| output would peak at 1.7MW.
|
| A more conservative 17 m/s2 for dust storms still yields
| about 308kW.
|
| 100m class wind turbines, while rare on Earth (e.g. GE
| Haliade-X [1]) would be easier to build on Mars given the
| significantly lower gravity.
|
| Wind turbines would work on Mars and have great synergy with
| solar - when solar doesn't work (e.g. during dust storms),
| wind turbines would be most efficient.
|
| Wind power wouldn't be the first choice for powering a Mars
| station, though. As can be seen above, installations would
| have to be pretty significant in size to deliver noteworthy
| amounts of power.
|
| [0] https://nssdc.gsfc.nasa.gov/planetary/factsheet/marsfact.
| htm...
|
| [1] https://www.ge.com/renewableenergy/wind-energy/offshore-
| wind...
| Denvercoder9 wrote:
| I don't think 100m wind turbines on Mars are feasible
| anytime soon. Even Starship has only a 18m high cargo area,
| so even if we assume that blades are assembled out of two
| parts in-place, you get only a 40m radius. That reduces the
| average power to just 10 kW.
|
| Furthermore, I think your average 10 m/s is an
| overestimation -- the source gives it as the high limit
| outside of dust storms.
| qayxc wrote:
| > I think your average 10 m/s is an overestimation -- the
| source gives it as the high limit outside of dust storms.
|
| You misread the source then - peaks during sandstorms are
| 17 - 30 m/s2 with 10 m/s2 being the annual average.
|
| > I don't think 100m wind turbines on Mars are feasible
| anytime soon.
|
| Manufacturing of the wind turbine is assumed to entirely
| take place on-site. Wind power is not something for a
| "starter station/settlement". The question was about
| general viability and given local manufacturing
| capabilities, wind power isn't completely useless on
| Mars.
| Denvercoder9 wrote:
| _> You misread the source then - peaks during sandstorms
| are 17 - 30 m /s2 with 10 m/s2 being the annual average._
|
| Where on the page? The only wind speed related data I can
| see is this:
|
| _> Wind speeds: 2-7 m /s (summer), 5-10 m/s (fall),
| 17-30 m/s (dust storm) (Viking Lander sites)_
|
| Also m/s2 isn't the correct unit for wind speed, since
| it's a unit of acceleration, not speed.
| dylan604 wrote:
| >Given a wind speed of 7 m/s2
|
| Isn't speed m/s and acceleration m/s/s?
| qayxc wrote:
| Yep it is - typo on my part.
| HPsquared wrote:
| A 100m wind turbine would require a lot of material and/or
| energy to construct, though - some of the materials would
| have to be processed locally, I wonder what the embodied
| energy of such a structure would be, and how long it would
| take to be net energy positive.
| godelski wrote:
| > would be easier to build on Mars given the significantly
| lower gravity.
|
| In one sense yes, but in another sense no. Consider
| erosion. It is the bane of existence for any system near
| the ocean. Mars has a similar problem with dust, which is
| smaller than what we see on Earth. This shreds electronics
| and other instruments on Mars. Sealing becomes far more
| important, but also more difficult. The other thing we need
| to recognize is that on Mars there's no electric ground.
|
| So yeah, on surface things look easier but there's a reason
| why including domain experts in the conversation is
| necessary. This is a classic example of napkin modeling
| being representative of how things will work in reality.
|
| So look to the domain experts. They've used solar and
| nuclear for a reason. Maybe dig into why those were the
| choices made.
| ncmncm wrote:
| What does it mean to say "there is no electric ground" on
| Mars? You would not be willing to drive a spike deep into
| the ground, as is done on Earth? Or are you saying that
| without ground moisture, the ground would not be
| conductive enough?
| godelski wrote:
| It has to actually do with the magnetosphere. It's not
| about will to put a spike of metal into the ground but
| that doing so doesn't create an electric ground like it
| does on Earth because there is not this electromagnetic
| differential.
| ncmncm wrote:
| That makes no sense.
|
| What has a planetary magnetosphere got to do with
| electrical ground? The planet itself is a spherical
| conductor. There probably is an ionosphere, although I
| would not be surprised to find that it is much nearer
| ground level than ours.
| qayxc wrote:
| There are solutions for that problem which involve a tiny
| source of alpha radiation and the atmosphere. Basically a
| modified lightning rod.
| godelski wrote:
| Source? I'm not quite sure what you're saying and I
| haven't heard of it myself.
| qayxc wrote:
| Sure thing. Here you go: Safe on Mars
| Precursor Measurements Necessary to Support Human
| Operations on the Martian Surface (2002) Ch.3
| Physical Environmental Hazards, Pg. 21
|
| > A combination of technologies might also be considered,
| such as point-discharge, needlelike devices or even small
| radiation sources to prevent charge buildup. [0]
|
| The small radiation sources refer to weak sources of
| alpha radiation (think smoke detectors), whose low-energy
| alpha particles collide with the atmosphere, ionizing it
| in the process. The now conductive atmosphere in the
| vicinity of the rod-device would then be able to
| neutralize excess charge.
|
| [0] https://www.nap.edu/catalog/10360/safe-on-mars-
| precursor-mea...
|
| The PDF version is available free of charge. The book can
| also be read online for free.
| moreati wrote:
| > on Mars there's no electric ground.
|
| I'm intrigued. Is it due to much drier conditions? Grain
| size? Mineral composition? Combinations? Anywhere I could
| read a bit more?
| godelski wrote:
| It's because Mars's magnetic core isn't spinning, which
| is also why there's no magnetosphere.
|
| As a quick intro that isn't doesn't have much detail but
| has links I'd go with[0]. But if you pick up any book on
| Martian engineering or read any report (NASA reports are
| public) you'll find mentions of this. This is also
| discussed deeply in most astrophysics textbooks.
|
| [0] https://hackaday.com/2017/08/17/living-on-mars-the-
| stuff-you...
| ceejayoz wrote:
| Not very.
|
| https://www.nasa.gov/centers/ames/news/releases/2001/01_72AR.
| ..
|
| > "Only during dust storms on Mars is there enough wind
| energy to operate a wind turbine," said Michael Flynn,
| another NASA Ames scientist. On Earth about 10 meters (33
| feet) per second wind speed is needed to make electricity
| with wind turbines; on Mars about 30 meters (98 feet) is
| needed because of the extremely thin air, according to
| Bubenheim.
| qayxc wrote:
| Incidentally, though, during storms is when power is needed
| most, as solar won't work very well during that time.
| ceejayoz wrote:
| Sure, but a nuclear plant solves that issue _without_
| sitting around being useless 90% of the time.
| qayxc wrote:
| But do you have the necessary infrastructure to maintain
| a nuclear reactor on Mars?
|
| As the article points out, the device required
| significant manpower, had reliability issues and wasn't
| cost effective.
|
| While it'd be relatively simple to build wind power
| locally once infrastructure is in place, the same cannot
| be said for nuclear power on Mars.
|
| Autonomy and self-reliance are critical factors for
| outposts on Mars - a point that cannot be overstated.
| fastball wrote:
| We've made a lot of improvements to nuclear reactor
| design since the 60s, and potentially we'll have working
| fusion by the time we have a colony on Mars, which would
| probably be the best solution (can easily get H from
| water and then would have He which is useful).
|
| I can't imagine a viable self-sufficient Mars colony that
| doesn't involve a lot of manpower anyway (I'm talking
| thousands of people).
| qayxc wrote:
| Well a working fusion reactor would render any current
| power source obsolete anyway.
|
| I wasn't necessarily thinking about complete self-
| sufficiency, just the fact that it might take up to 21/2
| years to get replacement parts.
| ClumsyPilot wrote:
| We have since deployed many nuclear reactors in space,
| with totally different reliability, so those should be
| used as reference. They can be packed on a rocket,
| launched, turned on and work for years unattended ( they
| powered societ radar satellites)
|
| Cost is dominated by weight in space, and a large wind
| turbine needs hundreds to thousands of tons of concrete
| for foundations - are those going to be brought from
| Earth? Can you make concrete on Mars?
| [deleted]
| petre wrote:
| Pray that the rocket doesn't blow up spreading nuclear
| fuel all over the place. Here is a Soviet "success story"
| involving a nuclear reactor on a sat.
|
| https://en.m.wikipedia.org/wiki/Kosmos_954
|
| Concrete would need cement made with limestone and
| massive amounts of heat and water which is scrace on
| Mars.
| ClumsyPilot wrote:
| Nuclear fuel that has never been "fired up" in a reactor
| is almost hamless - its just uranium. You could have it
| under your bed and you'd be fine, just don't eat it.
|
| In this case the reactor would only be started once it
| arrives on mars.
| petre wrote:
| I know, that's why I did not say radioactive waste.
| [deleted]
| erk__ wrote:
| The US did a similar thing at Camp Century [1] on Greenland. They
| installed a PM-2A nuclear reactor there, as far as I know they
| relayed very sparse information to the Danish goverment during
| the time, especially about the secret Project Iceworm [2].
|
| There was a danish article about it with some good pictures of
| the camp including one which looks like a part of the reactor [3]
|
| [1]: https://en.wikipedia.org/wiki/Camp_Century
|
| [2]: https://en.wikipedia.org/wiki/Project_Iceworm
|
| [3]: https://www.dr.dk/nyheder/webfeature/century
| psanford wrote:
| The was also the B-52 crash out side of the Thule air force
| base in Greenland, which was carrying a nuclear warhead[0].
| This, in an area designated as a nuclear-free zone by the
| Danish government.
|
| The cleanup project was unofficially referred to as "Dr
| Freezelove" by the Americans involved, which is a bit
| disturbing when you think about how Dr. Strangelove ends.
|
| [0]:
| https://en.wikipedia.org/wiki/1968_Thule_Air_Base_B-52_crash
| acidburnNSA wrote:
| And there's a great 30 minute video about it as well! [1]
|
| [1] https://www.youtube.com/watch?v=28NYczAuXl4
| MomoXenosaga wrote:
| I have no doubt the Danish government knew exactly what was
| going on just not in an official capacity that would allow them
| to answer any questions in parliament. The Japanse use the same
| sophistry when asked about nuclear weapons on US bases (in
| violation of the Japanse constitution).
| dukeofdoom wrote:
| My Dad was telling me some story how there's a secret military
| base in volcano in Antartica built by by Nazis. I'm convinced he
| was retelling a movie plot line. Anyone see a movie like this?
| ClumsyPilot wrote:
| >"it was plagued with problems which ultimately forced its early
| retirement in 1972"
|
| We really need a small reactor witha well tested design, where
| all the bugs and terthing problems have beeen worked out. It
| would be so usefull for situatioms like this.
|
| "223 reports of abnormal levels of radiation were recorded" Yeah,
| I would not want to stay at that base.
| hkai wrote:
| Here's an idea that Russians did. Put it on the boat!
| Transportable, plenty of coolant.
|
| https://en.m.wikipedia.org/wiki/Russian_floating_nuclear_pow...
| kilroy123 wrote:
| That's a damn good idea actually. Though, not so practical in
| Arctic waters.
| acidburnNSA wrote:
| Shipyard constructed floating nuclear power stations are a
| truly excellent idea. You get economies of mass production
| and scale in the factory to reduce costs and speed up
| timelines, and you get extra safety from being in coolant,
| decoupled from earthquakes, and in deep enough water to not
| have tsunamis. You have more weather to worry about, and
| piracy, but in the balance shipyard nuclear is one of the
| most intriguing ways to really decarbonize the planet at
| scale quickly.
|
| In the US, Offshore Power Systems tried this in the 1970s.
| They hired 1000 people, formed a joint venture with Newport
| News, bought and installed the world's largest gantry crane
| at their construction yard in Jacksonville, FL, and got a
| license to construct 8 gigawatt scale floating reactors from
| the Nuclear Regulatory Commission. Wild story [1].
|
| [1] https://whatisnuclear.com/blog/2020-01-26-offshore-power-
| sys...
| Krasnol wrote:
| Why are they an excellent idea? Where would it justify the
| cost of construction and operation?
| Robotbeat wrote:
| We should do this in Newport News (near the existing
| nuclear shipyard), actually. Great use of the coal terminal
| area once we retire those.
| julienchastang wrote:
| Whats more: "In addition to problems with the drinking water
| and environmental contamination, there were several recorded
| instances of crew radiation exposure, some resulting in injury.
| [7] During the plant operation, 223 reports of abnormal levels
| of radiation were recorded. [7] Of these cases, 14 resulted in
| injury and 123 resulted in exposure in the amount of 0.350 rem
| over a period of 7 days."
|
| What was the nature of these injuries?
| tantalor wrote:
| terthing?
| unwind wrote:
| *Teething, for sure.
| dekhn wrote:
| I think other folks are saying this but the navy solved this
| problem decades ago.
| freeflight wrote:
| That's just not really true.
|
| If that'd be the case then such small nuclear reactors would
| be powering US military bases and outposts all over the
| planet.
|
| This ain't a thing for a myriad of reasons, starting from
| cooling (not much ocean in the middle of the east), to
| profileration risks (navy designs using weapons grade
| uranium).
| dekhn wrote:
| I'm sorry, I should have said the Army:
| https://en.wikipedia.org/wiki/Project_Iceworm shows that we
| were definitely experimenting with nuclear power for remote
| military bases. They struggled with air-cooling. I consider
| reactors with weapons grade uranium to be an acceptable
| risk, but I don't think it's required for the army reactor
| style.
| tkojames wrote:
| Army is defacto banned to work on anything involving
| nuclear energy or weapons for awhile now. Rumor is the
| government does not trust. Pretty interesting. USAF is
| well quite scary with how bad they manage our nukes..
| p_l wrote:
| USAF, or specifically SAC, put priority on nuking as many
| civilian areas in as short amount of time as possible.
| Safety was a distant concern in that mindset, and led to
| fun stuff like first generation PADs (which controlled
| arming process of the warhead) being commonly (iirc, up
| to 50%?) configured to accept _all zeroes_ as arming
| code.
|
| USN at the same time considered PADs to be undue slowdown
| in the same mission _and_ had enough power to just not
| have them mounted, afaik.
| JackFr wrote:
| I would say it must be a cost issue. The US Navy now has 65
| years of experience running portable, robust, self-contained
| nuclear reactors, yet because of cost (and presumably safety)
| they only put them in submarines and aircraft carriers, where
| there are compelling use cases that can't be satisfied by
| fossil fuel power plants.
| duxup wrote:
| Nuclear powered submarine has a highly trained crew, many are
| busy monitoring / servicing the reactor.
|
| And the reactor brings itself home for service if needed.
|
| That seems way different than what you'd want in Antarctica.
| devoutsalsa wrote:
| We can build small reactors if we really want them. Here's a
| recent by the Illinois Energy Prof explaining one such case:
|
| "SMR - Small Module Nuclear Reactors -- Gas Cooled" =>
| https://youtu.be/TYnqJ4VnRM8
| Animats wrote:
| Hopefully better than last time.
|
| - Fort St. Vrain, US[1]. High temperature gas cooled
| reactor. Operated for 12 years. Corrosion problems.
| Converted to natural gas.
|
| - AVR reactor, Germany.[2] Pebble bed reactor. Had a pebble
| jam. Not repairable. Most fuel removed. Pressure vessel
| remains on site, with hope of full decommissioning in a
| century or so.
|
| There's a small reactor of this design working at a
| university in China, and a medium sized one one (200MW
| electrical output) is supposed to come on line this year.
| We'll see how that works out.
|
| Boring old boiling water and pressurized water reactors
| have simplicity in the radioactive part, and water is easy
| to handle. Designs that involve moving pellets or chemical
| processing of radioactive fluids add much complexity to a
| system that is very hard if not impossible to repair. The
| track record of such reactors is not good.
|
| [1] https://en.wikipedia.org/wiki/Fort_St._Vrain_Generating
| _Stat...
|
| [2] https://en.wikipedia.org/wiki/AVR_reactor
| p_l wrote:
| Boring old water cooled reactors (both boiling and
| pressured) are comparatively dangerous compared to quite
| well tested lead-bismuth cooled small modular reactors,
| which not only loadable on train car as self-contained
| part that needs no internal access, but _are self-sealing
| in case of failure_.
|
| Of course it's not as exotic as pebble bed reactor, or
| helium-cooled uranium-thorium reactor.
| xoa wrote:
| For the USN (and other military's) ones at least there are
| many other differing issues and design goals that are
| divergent enough from civilian usage that it's definitely
| more then just cost. For example on the most basic issue of
| fuel, the A4W reactors (found on current USN super carriers)
| run on highly enriched U235, designed around 93% and as high
| as 97%. In other words, the fuel is flat out weapons grade by
| itself. A typical civilian plant is more like 3-5%. Very high
| enrichment allows more density and very long times between
| refueling, they can go something like 10 years vs 1-2 years
| for civilian. But obviously that would be a big proliferation
| concern even ignoring cost, nor are there many places to get
| that kind of fuel. For the military that is irrelevant, it's
| not a limiting problem since the vessels these reactors live
| on tend to also carry literal nuclear weapons. But it means
| it won't just transfer to other usage. There are plenty of
| other differences in naval reactors, like they also formulate
| with high burn up fuels (metal ceramics, u-al/u-zr) rather
| then uranium dioxide.
|
| Military vessels also have ample trained personnel to throw
| at maintenance and operations, they can make tradeoffs for
| things that are more finicky but provide higher performance.
| They're anything but "self-contained" really, and even the
| Navy wanted to simplify that. A major goal for the new A1B
| reactor in the Gerald R. Ford-class supercarriers, as well as
| normal stuff like "more power, weighs less" was to cut the
| number of people needed to run the reactors and propulsion.
|
| I mean, yeah, all this certainly does add to the cost too.
| But it's not just about the cost, or rather the design goals
| and missions are divergent enough that they _necessitate_
| costs for military reactors that would be a waste, dangerous,
| or both elsewhere. Where the Naval reactors might well carry
| over to I think would be future space usage, a lot of what
| the navy is worried about with sending a reactor out on a
| carrier or sub for years seems to overlap with challenges and
| goals faced by a reactor on a spaceship sent to the outer
| solar system.
| nickelpro wrote:
| Can't put a traditional naval reactor or anything that
| resembles one on a spacecraft.
|
| 1) If it explodes on takeoff you're fucked
|
| 2) Naval reactors (and all reactors) require massive
| heatsinks to dissipate entropy. There's no ocean in space.
|
| Space-based nuclear energy is all based around RTGs,
| reactors have no place in space
| deeviant wrote:
| > Space-based nuclear energy is all based around RTGs,
| reactors have no place in space
|
| It is true that RTGs are the only type of nuclear power
| used in space now, but that is more to do with type of
| craft we send to space rather than practical limitation
| of nuclear power in space.
|
| A large spacecraft will have enough surface area mount
| enough radiative heatsinks to dissipate the heat from a
| nuclear reactor. Designs exist that have the math worked
| out for this since the 50s.
| marcinzm wrote:
| The soviets launched a bunch of reactors (not RTGs) into
| space.
|
| https://en.wikipedia.org/wiki/TOPAZ_nuclear_reactor
|
| https://en.wikipedia.org/wiki/BES-5
| acidburnNSA wrote:
| Almost all space reactor concepts have fresh fuel at
| takeoff and then start-up once they're launched. You can
| hold fresh nuclear fuel in your hand with very little
| hazard. It's only once you start splitting atoms that the
| radiation levels get high. So you launch the fresh and
| mostly inert reactor to avoid this risk.
|
| RTGs, on the other hand, are radioactive from the get-go,
| but are usually quite small.
|
| The USA did run a reactor in space (SNAP-10A) and the
| Soviets did a few dozen.
| nickelpro wrote:
| SNAP was a scaled up RTG, as are the soviet examples. You
| can call these reactors if you want but then we're just
| playing a semantics game. I tried to head this off by
| saying "traditional naval reactor or anything that
| resembles one".
|
| Also the problem isn't running the reactor on the launch
| pad, the problem is if the launch vessel explodes and the
| fuel load gets spread out over your launch area. The
| enriched uranium used in naval-style propulsion is
| absolutely not "safe to hold in your hand" and the weight
| requirements for using natural uranium, which is safe,
| would be prohibitive for use in space.
| cameldrv wrote:
| The odd numbered SNAPs were RTGs. The Even numbered ones
| were reactors. SNAP-10A was the only reactor from that
| program to fly.
| acidburnNSA wrote:
| Most SNAPs were RTGs but SNAP-10A was an honest to
| goodness fissioning nuclear reactor [1].
|
| [1] https://en.wikipedia.org/wiki/SNAP-10A
|
| Highly enriched uranium is still barely radioactive, very
| similar to natural uranium. The half-life of U-235 is 703
| million years. As half-life approaches infinity, atoms
| approach stability. The dose rate of holding navy nuclear
| fuel is modest compared to the hazards of fission
| products.
| djcapelis wrote:
| I don't disagree that in comparison to many other nasty
| byproducts of the U235 chain, most Uranium isotopes are
| not that "hot" but the danger of HEU comes partly from
| the increased presence of the U234 isotope, not just
| U235. So that isotope solely is not the right half life
| to do math around. While U235 is about as stable as U238,
| most purification techniques result in selecting the
| lower weight isotopes, which selects the hotter U234 as
| well. And while there is less of it, if I recall
| correctly eventually U234 dominates in terms of radiation
| output.
| nickelpro wrote:
| Again this is a semantics game, SNAP 10A was still
| driving a thermo electric converter, thus "scaled up
| RTG", nothing resembling a traditional naval reactor.
|
| The on-contact for a HEU billet is over 10mrem/hour. You
| and I have very different ideas about nuclear safety
| apparently and I presume you haven't worked
| professionally in the field with that attitude.
| mumblemumble wrote:
| Frankly, it seems to me that you're the one trying to
| make it a semantics game, by trying to define what is and
| is not a nuclear reactor based on how you collect power
| from the device.
|
| According to that Wikipedia article, SNAP 10A was
| centered on a device that created and maintained a
| controlled, sustained nuclear fission reaction. I would
| call that a "nuclear reactor" even if no attempt were
| made to harvest the power. I think that the rest of the
| world is probably with me on this. The Chicago Pile 1 is
| widely regarded as the first nuclear reactor, and nobody
| particularly cares how it generated electricity. What
| they care about is that it demonstrated a controlled,
| sustained nuclear fission reaction.
| [deleted]
| ClumsyPilot wrote:
| >"Again this is a semantics game, SNAP 10A was still
| driving a thermo electric converter, thus "scaled up
| RTG""
|
| You are getting the absolute basics wrong, so you have no
| standing to question the OP's atittude.
|
| Nuclear reactor runs a nuclear chain reaction, hence the
| name, RTG does not. There is no scope for debate here.
| The difference is night and day and is obvious if you
| look at fuel, power to weight ratio, or do physics 101.
|
| RTGs run on decay heat and use plutonium 238, they cant
| be turned off, their power slowly drops off over decades.
| Reactors use U235, have active control and starting/stop
| procedure and 10-100x higher power to weight
| Retric wrote:
| The issue is these designs are ~3% efficient like RTGs
| and have few moving parts unlike ~35% efficient nuclear
| reactors on earth. While they sidestep most of the
| complications of traditional nuclear reactors like
| radiation shielding, they really aren't useful designs
| having low energy output, terrible energy density,
| relatively short lifespans, and extreme cost.
| ClumsyPilot wrote:
| They have same radiation shielding and powet output as
| any other reactor, electricity generation is a separate
| concern that should not be confused with the reactor
| itself.
|
| The same reactor couod be hooked up to a 20% efficient
| stirling engine to keep it low maintenance, to a >50%
| efficient convined cycle or have 0% electricity output
| and be used for heat or water desalination.
| Retric wrote:
| Nuclear reactors aren't plug and play, and you can sell
| they skipped a lot of radiation shielding simply from the
| weight of these systems.
|
| By comparison SL-1 a 400kw thermal design so 4x power
| used a 12,000 kg pressure vessel including shielding.
| https://en.wikipedia.org/wiki/SL-1
| mumblemumble wrote:
| According to https://www.etec.energy.gov/Operations/Major
| _Operations/Majo... it's even worse than that; 1.83%.
|
| That said, it seems like, all by itself, conversion
| efficiency is a tricky measure of the usefulness of a
| design for spaceflight purposes. Wouldn't it be more
| useful to consider the total cost to deliver a given
| energy production capacity to space? In that case, rocket
| fuel itself, and the tyranny of the rocket equation,
| becomes a major consideration. If an efficiency gain
| comes at the cost of increasing the weight of the energy
| generation system in some way, then perhaps it doesn't
| end up being a net win over the less efficient design.
| Retric wrote:
| Efficiency is a big deal in part because you need to
| radiate out all that thermal energy. A radiator that's
| dumping 100kw of thermal energy for 1.3kw of electricity
| is much heavier than a 1.3kw solar panel anywhere near
| earth. Add 50kg for fuel and and things look even worse.
|
| By comparison the voyager probe RTG used ~1/10th the fuel
| for a little over 1/10th the power.
| https://en.wikipedia.org/wiki/MHW-RTG So the only
| advantage was cheaper fuel.
| ceejayoz wrote:
| 10 mrem/hour seems to confirm the "barely radioactive"
| argument; the CDC says
| (https://www.cdc.gov/nceh/radiation/air_travel.html) that
| a cross-country flight exposes you to 3.5 mrem. No one's
| saying you should hold said uranium in your hand for
| weeks at a time; they're saying the risk of chucking some
| around after a (very rare) spacecraft crash is pretty
| minor, especially as it'll be launched over water.
| discordance wrote:
| Except for the sun
| wpietri wrote:
| This is the kind of comment that keeps me coming back to
| HN. Thoughtful, nuanced, and full of information from a
| field I know very little about. Thanks!
| anon_tor_12345 wrote:
| On the other hand this is the kind of comment that keeps
| me away from HN. Full of self-congratulatory fawning.
| Thanks!
| jabl wrote:
| Except for the USN and RN (which uses US-derived designs),
| other navies using nuclear propulsion don't use such highly
| enriched fuel. Russia AFAIK uses somewhere around 30-40%,
| which is still classified as HEU, so problematic for
| civilian use, but most likely not directly usable in a
| bomb.
|
| France runs on 7% enriched UO2 (although using plate-based
| 'caramel' fuel rather than cylindrical pellets in rods like
| typical civilian nuclear fuel). This requires them to
| refuel every 10 years rather than having life-of-ship
| reactors like the latest generation US submarine reactors,
| but OTOH French law requires reactors to be defueled and
| inspected every 10 years anyway.
|
| As for space usage, launch weight restrictions make LWR
| style reactors impractical. Look at something like the NASA
| Kilopower as an example of what a (very small) space-based
| power reactor might look like. For nuclear propulsion like
| a nuclear thermal rocket, that's again a different kind of
| reactor pretty different from both LWR's and Kilopower.
| xoa wrote:
| > _As for space usage, launch weight restrictions make
| LWR style reactors impractical._
|
| OK, so this is a reply to both you and @nickelpro (your
| comment is newer but also higher), who wrote:
|
| > _Space-based nuclear energy is all based around RTGs,
| reactors have no place in space_
|
| You both seem to have an image in your heads regarding
| future long duration deep space vehicles (I explicitly
| mentioned "outer solar system") here that is a mixture of
| old space assembly and soft science-fiction, wherein
| industrial capacity is all terrestrial and any ship is
| built entirely on Earth, launched and off it goes. All-
| in-one. Even SpaceX with its use of pure chemical rockets
| to Mars and terrestrial construction plans to break with
| that: in-orbit refueling is an absolutely key part. And
| for going farther then that (and as Starship and
| successors/competitors kick starts a new era of space
| economics and industry) the clear and _necessary_ next
| step will be in-space assembly (be it in LEO or a
| Lagrange point dock or whatever ends up being most
| practical at a given time).
|
| In the same way we don't expect our ships to somehow be
| built hundreds of miles inland and then make their way to
| the ocean or fit entirely on a single semitruck, stay
| indefinitely on what can be launched out of Earth's
| atmosphere makes no sense either. The important aspects
| are all at cross purposes. Aerodynamic considerations are
| a waste in vacuum and constrict design in very important
| ways. Engines to get out of a strong gravity well need
| high thrust, whereas for long distances in space one
| really wants very high ISP. A torch drive that can do
| both necessarily bears a striking resemblance to a high
| energy weapon system to whatever happens to be facing the
| business end of it, and all known practical models
| (nuclear salt water, thermonuclear pulse) are ludicrously
| polluting. And outer solar system ships will need strong
| variable electric sources with high power/mass too
| despite solar being entirely impractical. RTGs won't cut
| it.
|
| So sure I don't think we'll ever see one launch off
| Earth's surface (I hope not anyway, if humanity is
| willing to light one of those off here it means we're
| facing a threat big enough that trashing our home is
| considered worth it). But that's a-ok, because what we'll
| do is built empty reactors, or reactor components, and
| launch those separately from fuel, and put it all
| together in space. Or for that matter far enough down the
| road maybe we build that stuff on the moon or in the
| asteroids or who knows. It obviously wouldn't be a
| copy/paste, but to the extent that USN reactor designs
| will get used outside of the military that's where I see
| it making sense.
| m4rtink wrote:
| In some cases you want sorta aerodynamic vehicles even if
| they are space only, as you then can do aerocapture and
| aerobreaking, possibly reducing quite a bit the delta-v
| needed for a flight.
|
| Also high thrust engines if you can get them can make use
| of the Oberhausen effect & some maneuvers, like specific
| orbit captures or crewed radiation belt transits need
| them as well.
|
| Still no problem to build that thing in space if you can
| pull it off. :)
| perl4ever wrote:
| >So sure I don't think we'll ever see one launch off
| Earth's surface
|
| Are you saying you don't think a nuclear reactor powered
| spacecraft will ever be launched into space on a chemical
| rocket in the forseeable future, or that you don't think
| nuclear powered rockets will ever be used to get from
| ground to orbit?
|
| You're probably aware, but nuclear power in space has not
| been limited to plutonium powered RTGs that output a few
| hundred watts.
|
| https://en.wikipedia.org/wiki/US-A
|
| https://en.wikipedia.org/wiki/BES-5
|
| https://en.wikipedia.org/wiki/TOPAZ_nuclear_reactor
|
| https://en.wikipedia.org/wiki/RD-0410
|
| https://en.wikipedia.org/wiki/Nuclear_power_in_space
| jabl wrote:
| My point is that the requirements on a space reactor are
| sufficiently different than a naval reactor that I'd
| think you're better off looking for inspiration at things
| like Kilopower than the PWR's currently used in naval
| vessels. Yes, if you build the thing in space weight
| isn't such a critical factor as if you're launching it
| from Earth's gravity well, but weight still matters as
| it's mass you have to accelerate and decelerate as you
| zip around the solar system. A PWR is inevitably
| extremely heavy due to having to withstand the 15 MPa
| pressure (assuming naval PWR's have about the same
| pressure as civilian ones, I suppose they could be
| somewhat lower). Further, a critical issue for a space
| reactor is how to cool it. Radiative cooling in space is
| very bad compared what we can do down here. Thus to
| minimize the size of your radiators you want a reactor
| that operates at high temperature. Also in this respect a
| PWR is a very poor choice.
| briffle wrote:
| With an almost unlimited heat-sink available right next to
| the reactor, plus, nuclear technician training in the Navy is
| very, very difficult to pass.
| tbihl wrote:
| >nuclear technician training in the Navy is very, very
| difficult to pass.
|
| Rigorous, yes, but not "very, very difficult to pass". The
| Navy needs a consistent stream of replacement operators,
| and their preferred way of getting them is to take
| reasonably capable volunteers and tutor/coach/remediate as
| many people as needed once they're in that group.
| indymike wrote:
| As someone who was a reactor opreator in the US Navy I'm
| laughing my ass off at this: "very, very difficult to
| pass". 90% of the people I started training with were
| gone in the first two years!
| MurMan wrote:
| > 90% of the people I started training with were gone in
| the first two years!
|
| My experience too. Do you remember the "skyhook"? We'd
| return to the barracks after class and find that the guy
| next to you had vanished without a trace.
| merpnderp wrote:
| A lot of the cost is regulatory. Starting a project where
| 3/4ths of your time will be your construction crews idling
| while waiting on your army of lawyers to get injunctions
| lifted, makes the idea incredibly unattractive to investors.
| Which is the whole point of people who use the court system
| as a strategic barrier to new construction, even when they
| realize they'll likely ultimately lose.
| njarboe wrote:
| The problem is that it is insanely costly and cumbersome to
| get regularly approval to build an experimental reactor in
| the US (and elsewhere I presume) so nuclear tech is stuck in
| the 1970's, just 20 years after the first commercial reactor
| was built. Imagine still using cars, or trains, or computers
| after only 20 years of development.
|
| One has to design the whole reactor on paper before building
| it and get it approved by the Nuclear Regulatory Commission
| (NRC). If, when you build it, you find you need to make
| changes to the design that are above a certain threshold, you
| have to recertify (not sure of the details. Can't find a good
| link about this). Imagine trying to build something as
| complicated as a nuclear reactor and you can't make iterative
| improvements. NuScales design approval process, the approval
| to be able to build the first reactor, cost $500 million
| dollars, took 2 million man hours, included over 2 million
| pages of documents, and after submitting in Jan of 2017 did
| not get approval until around 4 years later in August of
| 2020[1]. This is just to be able to build the first design.
| No wonder nuclear power has seen no progress in the last 50
| years.
|
| Fortunately this company did persevere and now is planning to
| build the first power plant in Utah, hoping to be operational
| in 2030. The people/governments stating that climate change
| is a crisis, and I do believe there is way too much CO2 in
| the atmosphere, should be fast tracking this approved tech
| with as much money as usable to build thousands of these
| reactors as quickly as possible.
|
| [1]https://www.nuscalepower.com/technology/licensing
| beisner wrote:
| There should be pretty strict regulation for fission
| reactor development, simply because radioactive materials
| in runaway reactions can have totally uncontrollable,
| millennia-spanning consequences. Very few other
| technologies have this potential - even a regular chemical
| explosion poses little risk to future generations in a
| large radius. Certain materials (plutonium, for instance)
| can reach criticality very quickly and in tiny quantities,
| and plutonium is a byproduct of fission. (I'm not a nuclear
| physicist, so my understanding of the real potential here
| might be wrong, because I have no sense of the quantities
| that might be experienced).
|
| This isn't a defense of the current regulatory process. The
| time frames, in particular, sound pretty egregious (4 years
| to approve a prototype, and 2m pages of documentation feels
| like a lot, too, but again I don't know how these things
| are designed). But I would be extremely uncomfortable with
| lax regulatory oversight, given that nuclear accidents have
| permanent, irreversible impacts on society and geography.
|
| Now, small-scale reactors may be a different beast
| entirely. If the quantity of materials is pretty much
| guaranteed not to have potential to cause problems for
| anyone but the operators for a short period of time....
| Then there certainly seems to be a case for a shorter
| regulatory cycle. But I would be shocked if scale isn't
| already taken into account for the current regulatory
| burden.
| njarboe wrote:
| The US should set up a special zone for companies that
| wish to work with nuclear material and provide well
| designed containment labs to work in. I would nominate
| the nuclear test site in Nevada. That area was already
| used to test devices that purposely went super-critical
| and spread their nuclear material into the environment
| with the most powerful explosions man has ever created.
| cycomanic wrote:
| Those numbers are completely meaningless without comparison
| to how long it takes to get approval for other power
| plants. I could not find definite answers but this report
| [1] for Australia says it can take up to 15 years between
| original prospecting and operation of a windfarm. I found
| another source that said it takes on average 3.1 years for
| approval in Sweden (it was not clear if that applied to
| windfarm only). Several other sources talk about multi year
| time frames as well. Considering the comparable impact of
| nuclear vs e.g. wind 4 years is quite short. Also this also
| disproves that nuclear is 3xpensive because of regulation,
| other energy sources face similar regulation delays.
|
| [1] https://www.nwfc.gov.au/observations-and-
| recommendations/cha...
| njarboe wrote:
| What I am talking about is the approval to build the
| first version of the reactor. The demo reactor. Imagine
| if one had to wait four years and spend half a billion
| dollars to get approval of your design of a windmill (not
| windmill farm) before you could even build the first one
| to see how well it would work. Progress on windmill
| design would be slow.
|
| Actually building the power plant with the reactor at a
| specific location is a different problem.
| wyldfire wrote:
| > "223 reports of abnormal levels of radiation were recorded"
| Yeah, I would not want to stay at that base
|
| That's nothing, you should've seen what the local wildlife did
| to the Norwegian and US bases down there.
| perihelions wrote:
| I'm not familiar with this subject, what incident are you
| referring to?
| coolsunglasses wrote:
| It's probably a wry reference to John Carpenter's The
| Thing.
| redler wrote:
| That particular wildlife was actually not local.
| wyldfire wrote:
| Oh I dunno about that. IIRC it had been there for far far
| longer than the first human settlements on Antarctica.
|
| Who's the invasive species? The creature minding its own
| business for 100k years or the humans who start stirring
| Things up as soon as they get there? ;)
| Denvercoder9 wrote:
| _> We really need a small reactor witha well tested design,
| where all the bugs and terthing problems have beeen worked
| out._
|
| NASA's Kilopower is sort-of aiming to be this, though it has a
| long way to go to get there.
| Robotbeat wrote:
| Kinda too small, though. Those are just 1-10kWe each and
| extremely expensive.
| godmode2019 wrote:
| Was this public knowledge? That base is located on New Zealand
| territory and they are nuclear free by law.
| thewopr wrote:
| It was public knowledge. Further, there is no such thing as New
| Zealand territory (or anyone's territory for that matter) in
| Antarctica. There are existing territorial claims, but they are
| overlapping and basically nullified by the Antarctic Treaty.
|
| https://www.antarctica.gov.au/about-antarctica/law-and-treat...
| nuccy wrote:
| Moreover the New Zealand nuclear-free zone was established
| only in the 80s [1].
|
| [1] https://en.wikipedia.org/wiki/New_Zealand_nuclear-
| free_zone
| MattGaiser wrote:
| It is not really recognized as NZ territory as Antarctic claims
| are not recognized by most nations.
| andylynch wrote:
| This predates the New Zealand Nuclear Free Zone created in 1984
| and in any case this is not New Zealand territory. _But_ land-
| based nuclear power is perfectly legal in New Zealand, just
| unpopular & undeveloped, in favour of oil, gas, hydroelectric,
| and more recently wind. One unusual barrier to NZ nuclear power
| is that the common designs would be too big to maintain a
| balanced grid; a single 1GW commercial reactor could supply 1/7
| of NZ's electricity.
| mprovost wrote:
| While legally allowed it would be politically and culturally
| impossible at this point to build a nuclear power plant in
| NZ. The population has a strong Nuclear Free identity. For
| example, when you fly into Wellington, the sign on the way
| out of the airport says "Welcome to Wellington, Capital of
| Nuclear Free New Zealand".
| justin66 wrote:
| I didn't downvote you but it takes about 30 seconds to discover
| that the New Zealand Nuclear Free Zone, Disarmament, and Arms
| Control Act was passed in 1987, well after the reactor
| discussed in the article was decommissioned.
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