Fusion Power...wait what?

Discussion in 'General Fallout Discussion' started by NMLevesque, May 12, 2017.

  1. NMLevesque

    NMLevesque Commie Ghost

    618
    Jul 2, 2016
    Really confused right now. They had microfusion power ever since Fallout, as perishable ammo and power armor that never ran out of power. Which itself must mean that whatever amount of energy it takes to fuel a robotic exoskeleton for 100 years, is a fraction of the energy that an energy weapon can use in a single day. Which means it really can't be a nuclear battery as we understand it, and that calling both microfusion may be misleading.

    Either way it's pre-war tech, but every instance of an actual reactor appears to be fission until the later titles (e.g Candle fusion power in Hidden Valley, and everywhere in the game that shall not be named). So they had a small scale version that couldn't be scaled up, otherwise why was the Enclave using fission reactors?!?. I just thought the story was that fusion power came too late. Everyone was at war with each other, enemies all around, and America didn't want to share but they had it (hence the powered armor, laser and plasma weapons, and maybe the ubiquity of robots?). So where is it? I just don't understand what they were going for on this one.
     
  2. CT Phipps

    CT Phipps Venerable Relic of the Wastes

    Sep 17, 2016
    Maybe the robots are able to self-maintain themselves. According to Bethesda lore, lots of power lines still work since they connect to underground still-functioning nuclear power plants.
     
  3. Hassknecht

    Hassknecht For hate's sake. Staff Member Admin Orderite

    Aug 16, 2010
    The power armor specs of Fallout 1 say that the microfusion power generator on the T51b generates up to 60kW. That's certainly reasonable for a powered armor. The question is the total amount of energy and how much power does it generate at each moment.
    Normally, nuclear fusion is not something you can just turn on and off, but I'll assume that the microfusion technology of SCIENCE! is capable of quick start and stop procedures as well as output scaling. So we don't know how long the fuel lasts in the T51b under maximum output, but we can do a rough comparison with the output of the laser rifle.
    Lemme quote myself here from a different thread on MFCs:
    It's kinda hard to really estimate what the content of one MFC really is. Does one physical cell fully charge the laser rifle to twelve shots? Or does it make more sense to say that the ammunition counter in Fallout 1/2 is a bit more abstract? We'd have to differ between physical microfusion cells (which would then contain 120 kJ), and microfusion cell charges (which appear to be what the counter in your inventory in Fallout 1/2 shows you), which would be about 10 kJ per unit.
    Let's try comparing it to the Highwayman. I'll assume it to be slightly less efficient than a Tesla Model S, because it's bulkier and less aerodynamic. 30 kWh/100 km means 1080 kJ/km if I'm not mistaken, so let's round it down to 1000 kJ/km because I'm a physicist and I like round numbers. Also slightly less than a Chevy Volt in pure electric mode, which takes 810 kJ/km, so my numbers make sense I think.
    I have no clue what the range of the Highwayman is on flat terrain, but let's say it's 500 km.
    So 100 units of MFC charge give you 500 km at 1000 kJ/km. So the total energy in the full tank is 500,000 kJ, meaning that a single MFC charge is equivalent to 5 MJ, or 5000 kJ. So a few orders of magnitude different from what the laser rifle tells us. Of course, if we assume a single MFC charge to be 5 MJ and still want a single laser blast from that to be around 5 kJ of total energy, we could also lower the efficiency of the laser, which would have to be at about 0.001 instead of 0.5 as I assumed above. That's quite crappy. The laser in Fallout 1 and 2 is red, so it might either be a diode laser or a HeNe laser. 0.001 (or 0.1%) is actually about the efficiency of a HeNe laser in real life, although no high power variants exist (because of the low efficiency).
    If we'd assume one MFC charge to be 5 MJ, and, as in my quote above, one physical MF cell to contain twelve units (assumed from the laser rifle having twelve shots from one reload, which I assume means shoving one MFC into the gun like it's shown in the later games), the total energy content of an MFC would be 60 MJ. Thus the energy density of the MFC, which has a volume of 490 mm³, would be 12.25 GJ/l, which is much closer to nuclear fuel than to conventional batteries, but still magnitudes below it. Not too outlandish.
    And 60 MJ would keep your T51b moving at full power for about 16 minutes. But I assume the microfusion pack of the T51b is bigger than the MFC and more geared towards slow and steady energy production, and the full 60 kW output is not used all the time. So, dunno, if you squint a bit and ignore the fact that Fallout is SCIENCE! which doesn't really need to make too much sense, it actually kinda works out. Microfusion cells and so on don't use "hot" nuclear fusion like we know it, but some sort of fictional "cold" fusion process. It probably can't be scaled up too much, and its energy density is a bit lower than nuclear fission. So it's a great technology for transportation and weapons, but large scale power plants in the MW and GW range for national power grids don't really work too well with it, so they need to rely on "classic" nuclear fission power.

    Wow, that was a long and pointless post, but after thinking about all that stuff it occurs to me that despite Fallout not being written by scientists and probably just hammering in random numbers and buzzwords, it actually works out quite well. It's at least somewhat consistent. I'll have to ask some of the writers about scientific backgrounds if we can get one of them on the Podcast again...
    Anyway, I think I'll write a full article about the reasonable aspects of Fallout's SCIENCE! for NMA o_O
     
    • [Like] [Like] x 3
  4. NMLevesque

    NMLevesque Commie Ghost

    618
    Jul 2, 2016

    Well that was revalatory. Thanks! Now I just need to find some mentats...
    Edit: Oh um, when you wrote MJ/l I assume that means per Liter?
     
  5. Hassknecht

    Hassknecht For hate's sake. Staff Member Admin Orderite

    Aug 16, 2010
    Yes, Megajoules per liter.
     
  6. Ben Soto

    Ben Soto Professional Salt Shaker

    731
    Jul 7, 2014
    What bugs me about fusion technology is (like you handwaved, @Hassknecht ) the ability of a fusion cell to quick start/stop. You don't just stop fusion and it's really hard to get it started again. There must be some sort of secondary power source included to start up the fusion again.
     
  7. Hassknecht

    Hassknecht For hate's sake. Staff Member Admin Orderite

    Aug 16, 2010
    Actually, stopping is the one thing that's easy with (controlled) nuclear fusion. The reason for that is that controlled nuclear fusion requires extreme conditions that are immensely hard to achieve. In fusion reactors you either have to painstakingly create these conditions (and keep them up) to keep the fusion reaction going, and it's hard to just break even with the energy spent on that. As soon as something goes wrong the plasma will immediately cool and nothing will happen.
    It's incredibly hard to start them due to that, of course.
    But that's for nuclear fusion in our world. I think in Fallout microfusion cells are based on "cold" fusion (or LENR, as the apologists like to call it these days, Low Energy Nuclear Reactions or Lattice Enhanced Nuclear Reactions). The idea is that fusionable material adsorbed in condensed matter (like heavy water in palladium) will fuse easily. Basically, the original (and discredited) experiment on this was a palladium cathode in heavy water. The deuterium would adsorb into the cathode where it settles in interlattice positions. Since these interlattice positions are actually quite close to each other, it was thought that due to quantum mechanical uncertainties the deuterium atoms could achieve a low but significant rate of fusion. As I said, it was discredited, but there are still experiments going on in that direction. Mostly scams, though.
    That process could start and stop quite quickly, though, and could be made reasonably small, too, since you only need heavy water and a palladium cathode and a way to convert the resulting heat into electricity.
     
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  8. Ben Soto

    Ben Soto Professional Salt Shaker

    731
    Jul 7, 2014
    At first, I was about to say that it's explicity stated that cold fusion isn't a thing in the Fallout universe... but that's totally wrong. The G.E.C.K. is powered by cold fusion.
     
    • [Like] [Like] x 1
  9. Hassknecht

    Hassknecht For hate's sake. Staff Member Admin Orderite

    Aug 16, 2010
    It's all handwavium anyway. The Fallout Bible says that the cold fusion generator in the GECK could power a city, which is kinda weird. Handwavium and MacGuffinite are the main elements of SCIENCE!, after all, even though you can find many grains of truth in it if you squint hard enough.
     
    • [Like] [Like] x 2
  10. Ben Soto

    Ben Soto Professional Salt Shaker

    731
    Jul 7, 2014
    Yeah. I remember watching one of those "The SCIENCE! Of..." videos where Austin was talking about fusion cores, and math actually made it so that fusion cores would start going out after about 110 years (IIRC,) which is how long Fallout 1 said the fusion cores in power armor would last.
     
  11. NMLevesque

    NMLevesque Commie Ghost

    618
    Jul 2, 2016
    I kind of wish they stated this kind of thing clearly. If they said you know, the same experiment was done in the Fallout world except it had a different result. Therefore a particular theory is valid, and one that we use IRL is a bit off. Well, that would make for a good sci-fi foundation. It's one thing to just say physics works differently, but it's another to actually have an actual concept. Something that is a facet of the world and not just some kind of warning label that just says 'ignore all immersion breaking nonsense' b/c SCIENCE. Also, personally I prefer calling it superscience. Idk if anyone else here is really into the Venture Bros. but incidentally speaking, they do a good job of making shit up as they go along, and fixing issues thereof at the same time.
     
  12. peadar87

    peadar87 Still Mildly Glowing

    244
    Jun 4, 2015
    I think having reliable, widespread small-scale fusion creates more problems for the setting than it solves, so usually handwave away "Microfusion" as a brand name for what is just a very good battery.