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Future energy sources

  1. Dec 20, 2012 #1
    Hi everyone.

    I have a few ideas floating in my head for a story I would like to write. I have got nothing concrete yet so my story is still very flexible.

    First of all the story will take place in the nearish future, say in 80-120 years.

    First of all, I want some ideas of possible power sources, but power sources that could generate much more energy than today's power sources, because the energy needs of an advanced society would logically be much larger than today's power sources.

    Some ideas I had:

    #1 nuclear fusion, this is not a very exotic idea and could very well work.

    EDIT: accidentally posted.

    #2 Some type of satellite with some type of solar panels harnessing the sun's power at an high efficiency, and beaming it back to earth as microwaves to a collector.

    #3 This was my original idea and I have no idea if it violates any big law of physics.(please clarify) The idea is that there exists technology that can easily transform matter into its corresponding anti-matter. Then the anti matter and matter could be collided and we harness the resulting pure energy.

    Secondly I need ideas for weapon systems that are more powerful than our modern nukes. I know our nukes are pretty powerful as is, but the earth is in danger guys!

    #1 could it be possible to make a type of bomb with nuclear fusion technology ?

    #2 If I allow for my space satellite harnessing the suns power, and beaming it back as Microwaves you can very well just aim it at your enemies and cook them.

    #3 anti matter would make for quite effective bombs if it would be possible to produce and contain it.

    Any ideas for future energy sources and weapon systems that aren't extremely scientifically implausible are welcome. And comments on my ideas is also appreciated.

    EDIT: Combinations of energy sources is also an idea

    Posted this from my phone so excuse the poor formatting and please ask if you need more info.
    Last edited: Dec 20, 2012
  2. jcsd
  3. Dec 20, 2012 #2


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    That violates conservation laws in particle physics. While it is expected that those laws cannot not exact (as our universe has more matter than antimatter today), it is known that any deviations have to be extremely small (none was observed so far).

    As alternative, you could produce microscopic black holes and throw stuff into it. The accretion disk will give intense radiation, releasing up to ~30% of its mass-energy as radiation (for a rotating black hole).

    They are called hydrogen bombs or thermonuclear weapons. They exist.

    Probably, if you can focus those microwaves good enough. They are easy to deflect to >99% with metallic surfaces, however.

    Antimatter is problematic. Its energy density is good, but it is very expensive (at least in terms of energy), and how do you get it to the enemy?
  4. Dec 20, 2012 #3
    If making anti-matter is not an option then so is an anti-matter bomb.

    I like the idea of nuclear fusion. Although 30% of mass energy is much more than what a fusion reaction could achieve. I think that is a quite good source of energy.

    Thank you for your inputs. I think I can manage with micro-black holes as the prime energy source of the future.
    Last edited: Dec 20, 2012
  5. Dec 20, 2012 #4
    [sarcasm]Energy source? In a century finally renewables would become economically viable.[/sarcasm]

    As main source of energy - fusion. Part (10%?) of energy should be presumably produced from renewable. Maybe a big part of Sahara covered by solar panels or something of that scale.

    Gigantic (including merchant) ships with simple fission reactor should not be ruled out.

    Weapons? As last word, I would still think about old fashioned nuclear warheads. However, as the method of being able to retaliate to surprise attack I'd think about having warheads already prepared on orbit.
  6. Dec 20, 2012 #5


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    Hawking radiation is another option, if the black hole is small enough. See this paper for details. 80-120 years in the future, this looks like a possible technology.
  7. Dec 20, 2012 #6
    This was the general direction I thought my story would take, fusion energy is the norm and maybe even the idea of micro black holes. I'll do a bit of thinking about the plot and so on to decide if I will include the micro black holes.

    Another idea for weapons is lasers. Seeing as we have means to produce massive amounts of energy, could it be conceivable that lasers could be an effective weapon ? Even if it was a factory sized weapon designed for targets near earth's orbit ?
  8. Dec 20, 2012 #7


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    Lasers have an efficiency problem - you get something like ~10% of the input power as laser light (even LEDs are better I think). The attacked ship could have a reflecting surface, so just a very small fraction of your input power reaches its target - and you need big radiators for the produced heat.
  9. Dec 20, 2012 #8
    I thought about the reflective surface problem, but I have always thought lasers were quite efficient and that is why I thought they would be an effective weapon.
  10. Dec 20, 2012 #9
    On a side note there is a naturally occurring sources of anti-matter right in Earths orbit.

    See this Article
  11. Dec 20, 2012 #10
    What about using lasers as fixed point defences against planes and re-entering warheads? I mean you can connect that to your existing grid. You can also cool that easily. (pools with coolant are inexpensive ;) )
  12. Dec 20, 2012 #11


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    An optimistic estimate based on figure 1 in the publication is ~100 antiprotons per m^2 and second. Annihilating them gives ~5nW/m^2, this includes the kinetic energy of the antiprotons. Compare this with ~1kW/m^2 solar radiation - 11 orders of magnitude more.

    The publication itself does not mention any application of those antiprotons - and I think the authors know why.

    @Czcibor: Ground-based lasers: Why not. Lasers on ships and airplanes are tested, too.
  13. Dec 21, 2012 #12
    Wow, the paper is interesting indeed. I wish they've spent more time calculating examples of how far the starship would reach in, say, human lifetime. Also, why don't they consider having an accretion disk at the BH engine? I know that the total efficiency will be lower, but then you could have jets, which would give you better acceleration and smaller shield. Wait, you could drop that 10^9 kg laser altogether, and try to contain the black hole (charged) via EM force.
  14. Dec 21, 2012 #13
    Wow, interesting read. Micro black holes seem very possible. One question that I'm curious about myself is where the initial mass of the black hole comes from ?
  15. Dec 21, 2012 #14
    I think i just realised what the answer to my question was. The initial mass comes from the energy used to create the black hole. Is this correct ?
  16. Dec 21, 2012 #15


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    Right. And you need the massive array of lasers to get that energy density.

    Well, I think it does not change much. The spectrum might be a bit different (did not check this), but you get the same energy anyway. Accretion disks are mentioned in section V B to feed the black hole.
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