[HN Gopher] The Nuclear Lightbulb (2020) ___________________________________________________________________ The Nuclear Lightbulb (2020) Author : othello Score : 53 points Date : 2021-04-11 17:28 UTC (5 hours ago) (HTM) web link (beyondnerva.com) (TXT) w3m dump (beyondnerva.com) | tyingq wrote: | _" For those of us of a certain age, there was a toy that was | quite popular: the Easy-Bake Oven...Rather than having a more | normal resistive heating element as you find in a normal oven, | though, a special light bulb was mounted in the oven, and the | waste heat from the bulb would heat the oven enough to cook the | food."_ | | I can't find any evidence that the Easy Bake oven used a | "special" light bulb. It just used 2 normal 100 watt incandescent | bulbs as far as I can tell. Tungsten is a normal resistive | heating element, pretty common in electric furnaces. | | https://upload.wikimedia.org/wikipedia/commons/1/1e/Premier_... | | Though there was a 2006 redesign that apparently didn't go well: | https://www.cpsc.gov/Recalls/2007/new-easy-bake-oven-recall-... | Baeocystin wrote: | The one I played with as a kid used oven light bulbs. They look | pretty much the same, but solderless construction, and IIRC | quartz glass and a slightly more robust filament. | tyingq wrote: | Hmm. Any idea roughly what year? The manuals I can find | online all say "standard light bulb". | | Like: | | https://imgur.com/a/uF9ffe1 | | https://imgur.com/a/F7WwpGg | Baeocystin wrote: | Huh. Interesting. This would have been the late 70's/early | 80's. | Black101 wrote: | I just want a nuclear car... | SigmundA wrote: | A Tesla with nuclear power plants... | Black101 wrote: | but you have to stop to charge... I guess wireless charging | is coming though | nosmokewhereiam wrote: | "Our water pump went out" would go from being a 2 hour side of | the road fix or tow to potentially a mutli-decade incident... | | Either add a second pump or just power it from a legit non- | mobile federally rated reactor plant. | klyrs wrote: | Sure, but imagine it -- the road would be traffic-free for | decades! Nevermind the trees growing in the street... | Scoundreller wrote: | "If we stop, we'll overheat. We must go faster". | coolandsmartrr wrote: | In case you can't see the original link: | https://web.archive.org/web/20210130190443/https://beyondner... | philipkglass wrote: | I read some of the old United Aircraft Corporation reports about | the nuclear light bulb reactor the other weekend. The design | parameters are delightfully extreme. You can see why it wasn't | tested in later years. By the 1970s there was already much | diminished tolerance for experiments that ejected fission | products into the environment, and effective release prevention | for testing this design would be expensive. | | Here's one of the reports, from 1969: | https://core.ac.uk/download/pdf/85241637.pdf | | Some highlights from this report: | | - The fully gaseous core would operate at a pressure of 200 | atmospheres. This is somewhat higher than the pressure in a | pressurized water reactor core. | | - The vapor/plasma fuel temperature would be 42000 Rankine. | That's about 23300 Kelvin, roughly 4 times as hot as the surface | of the Sun. | | - The fiberglass pressure vessel was projected to last about 6000 | seconds (100 minutes) of full power operation before its strength | was compromised by neutron irradiation. | | - The preferred fuel was uranium 233, which does not exist to any | considerable degree in nature. It has to be bred from thorium. | Since U-233 never had significant use in civil or military | nuclear applications, the US has not produced any U-233 since the | 1980s [1]. Highly enriched uranium 235 or plutonium 239 would | also work, just not as well. All fueling options needed "bomb | grade" fuel purity. That was the only way to make the reaction | zone so compact. | | Other details that I recall from other reports -- sadly not ready | to hand: | | - Later iterations of the design kept thinning the quartz | envelope to maintain adequate transparency to UV radiation after | accounting for color centers induced by radiation damage. This | required aggressive/optimistic estimates of how perfectly | pressure could be equalized on both sides of the envelope, | particularly during start-up. | | - The optimal core fuel temperature would have been _even higher_ | except that it was difficult to find materials that would be | adequately transparent to even shorter ultraviolet radiation. | | - Fission products were supposed to be separated from the fuel | centrifugally before the fuel recirculated into the reaction | zone. This seems chemically optimistic to me. | | - There was little consideration of chemical factors in any of | the reports I read. Given that the environment was extremely hot, | rich in fluorine, and would soon contain most elements of the | periodic table from fission products, this seems like an | oversight. One that would probably be testable only by actually | building and operating test reactors. | | [1] https://www.world-nuclear.org/information-library/current- | an... | Causality1 wrote: | Things like this make me wonder how cheap a truly commoditized | nuclear industry could be. What kind of lifestyle are we giving | up by requiring orders of magnitude fewer deaths-per-megawatt- | hour of nuclear compared to fossil fuels? What if we were | civilized enough you didn't have to worry about anyone building | their own atom bomb? | numpad0 wrote: | I think we need to be a spacefaring species to be able to fully | utilize nuclear energy, and to be a spacefaring species, highly | automated orbital manufacturing has to be established. Doing | nuclear on the planet Earth at all is perhaps too akin to doing | it in the middle of Manhattan island. | vangelis wrote: | I think it be a lot like airliners vs small aircraft in terms | of safety. | ryan93 wrote: | Much cheaper than solar and wind. | URSpider94 wrote: | There is a lot of very complex, and very real human psychology | and sociology at play in those decisions. A lot of it centers | around who accrues the benefits of a given energy source, vs. | who pays the consequences. | choeger wrote: | Not that much. Nuclear energy alone wouldn't really make a huge | difference. Even if we ignore the obvious problems with safety | (big issue with older designs and their spent fuel storage) and | security (huge issue with modern designs) when nuclear power | would be similarly widespread as, e.g., natural gas: There is | still the fact that it is inherently a stationary power source | (with not that many good places to put it). Distribution of | electricity isn't a big problem, but it doesn't help for | mobility applications, so we would need the battery or H2 | industry anyways. | | Factor in the wastly different levels of difficulty between | solar and nuclear power, I'd think we would also have the | latter, if just as a simple alternative when you don't have the | time or the capital to setup a nuclear power plant. Wind energy | might be a different matter, as it comes with a lot more | practical difficulties. | | One could simply compare France and Germany to understand how | things would end up, I think. | marcinzm wrote: | >What if we were civilized enough you didn't have to worry | about anyone building their own atom bomb? | | Then we'd be something other than human. You'd need a species | that values all members equally and has no preference for those | in the same social group (or family, etc.). Likely it also | means members cannot value themselves above other members. | Without all that "civilized" simply means that some group gets | oppressed and isn't allowed to fight back in any way. | baybal2 wrote: | Keeping all core gasses confined is one option. A spec of dust on | the quart, crytaline defect, hydrogen embrittlement, or anything | else and you get R.U.D. | | Another is not to fight it, and let them go. The closest thing to | a torch drive possible with modern day engineering after the NSWR | is the open cycle gas core rocket. | | Thrust in meganewtons, and 1000+ ISP | th8700 wrote: | Nobody would accept the fallout if it's a ground launch. And if | it's a space launch, why not go directly to Project Orion? | baybal2 wrote: | Given economic considerations, both the open cycle gas core, | and NSWR may beat practical Orion drives. | jdc wrote: | It could make an _excellent_ fourth stage, however. | JulianMorrison wrote: | Nobody would accept the fallout if it was a space launch | either, given that crud might either hang about in LEO | poisoning it for everyone else, fall out onto the planet | below, or drift around in space forming a radiation hazard | for future travel. You'd have to get its speed up to solar | escape velocity to ensure it wouldn't be captured | _somewhere_. | api wrote: | Use it for the later stages in a many stage interstellar | rocket. First stages are chemical, then NERVA style | contained nuclear rockets, then open cycle nuclear when you | are already well past solar system escape velocity. | | I'm thinking of something like an interstellar flyby probe | for the Centauri system. It wouldn't be able to stop or do | much course correction but you could send basically an | autonomous space telescope that transmitted back | observations. It would be able to see planets in the system | much better than we can from here. | mrfusion wrote: | > drift around in space forming a radiation hazard for | future travel. | | Do you realize how big space is? | [deleted] | baybal2 wrote: | Radiation hazard of single digit nuclear rocket launches | will completely pale in comparison to total amount of | radiation coming from Sun, and space. | | Do you understand how much radiation it is in space? All | human nuclear experiments in 20th century together wouldn't | be even a rounding error there. | retrac wrote: | This does not follow. Photons from the sun are not | radioactive isotopes that can rain down on us as they | decay from orbit. And the magnetosphere protects us from | the bulk of the solar wind's traces of heavier isotopes. | How much plutonium or whatever, is in near-Earth space, | other than what we've sent up there? | | A more pragmatic argument is that, after the uncontrolled | fission of literal tonnes of plutonium and the release of | that and the byproducts into the atmosphere in the | previous century, the small risk of losing a few kg more | here or there barely registers. ___________________________________________________________________ (page generated 2021-04-11 23:00 UTC)