Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

How will fusion solve all the world's energy problems?

  1. Apr 12, 2008 #1

    KCL

    User Avatar

    Lately I've been watching a few documentaries on the future and fusion is treated as a solution to all energy problems. In the Discovery Channel 2057 documentary they say we'll never have to drill for another barrel of oil once fusion is achieved...

    Now from what I know the majority of oil goes to transportation - cars/trucks/airplanes... how does fusion help with those? I understand that energy to generate electricity for the world wouldn't be a big deal then, but cars? Will we have to drive electric plug-in ones? What about airplanes?

    Thanks for any answers. :)
     
  2. jcsd
  3. Apr 13, 2008 #2
    The ability to generate large amounts of electricity cleanly and efficiently in one spot leads to the production of fuel cells (ie the plants can produce the hydrogen needed) which can be used to power almost anything, although you make a good point about planes, im not sure you could get enough power of electric motors powered by fuel cells to drive em, but maybe you can.
     
  4. Apr 13, 2008 #3
    when there is near-infinite fusion energy, scientists can chemically reproduce liquid fuel using that energy. they can get the elements they want by breaking down anything in waste. in theory, they dont need to drill anything from the ground any longer :wink:
     
  5. Apr 13, 2008 #4
    Can you please provide a reference for that? I'm a big fusion optimist, and would like to know more about this. How exactly could we chemically produce liquid fuels such as kerosene from more abundantly available elements?

    I know kerosene is mostly hydrocarbons, and that carbon, and hydrogen are abundant, but what is preventing us from synthesising these fuels right now? Also, the carbon would still have to mined wouldn't it? Unless you are talking about alternative liquid fuels to those using hydrocarbons? Cheers
     
  6. Apr 13, 2008 #5
    hello optrix, i got this idea from local radio and i agree with that, since it is theoretically possible when one is given the required energy to construct the chemicals. however, i believe currently there is no such plan to develop method for efficient convertion from electricity to popular liquid/gas fuel, since the energy cost vs oil price does not make sense out of it. i tried some wiki and google and it led to nothing :wink:
     
  7. Apr 13, 2008 #6

    LURCH

    User Avatar
    Science Advisor

    I think that the switch to electric is assumed in those predictions. Yes, electrical power can provide sufficient thrust for proeller-diven aircraft, but I don't see it replacing the jet engine.
     
  8. Apr 14, 2008 #7
    Well oil came from somewhere..no? I don't know how oil did generated exactly on earth, but something that involve time ( a lot) and carbon "waste" and some kind of energy.
    Guess a similar process ( of course faster) can be engineerized if this is worth to do.
    So i think is possible, but i'm sure that when there will be no more oil, we will have already found some other way to let our plane flight without it or may be we will be using train fast as planes ( humm i don't belive that :-p).
     
  9. Apr 14, 2008 #8

    malawi_glenn

    User Avatar
    Science Advisor
    Homework Helper


    oil takes some milion of years to be produced altough
     
  10. Apr 14, 2008 #9
    If nature can...we can emulate it, as we always did.
     
  11. Apr 14, 2008 #10
    You can't use fusion in a car. So fusion is only half of an energy solution: fusion solves the problem of energy production. This leaves another problem unsolved: The problem of storage and transport.

    In other words, if you want to use fusion power as a total energy solution, then you have to find some kind of a generalized way of taking energy and storing it for use in a car or somesuch. There are several candidate technologies that could provide this energy transport layer: say electricity stored in batteries, or hydrogen. (Hydrogen is kind of the purest example of an energy transport technology.) However none of these technologies are "ready for prime time".

    This is not really a downside of fusion: It is my opinion we have to solve this problem and create an energy transport layer of this sort no matter WHAT our energy production solution. And the many years it may take to get hydrogen etc working doesn't seem like much of a concern considering it will take probably many more years to get fusion working in the first place.

    Incidentally there *are* technologies which are capable of "making" oil. For example biofuels are basically an example of this, they are a roundabout way of turning solar energy into oil. The downside of current biofuel technologies is that you have to do all that messy "agriculture" stuff to get them, which means they have high energy and environmental costs; but I guess if we had a perfect source of energy production, like fusion, we wouldn't really care how energy-expensive biofuels were to produce, would we?

    There are also interesting speculative technologies, such as thermal depolymerization, which basically "cooks" organic matter (i.e., trash) into oil in a way that mimicks geologic processes (as PhillipH describes) but is much faster. However this is very hard! None of these technologies seem to be going anywhere that I can see, and I find it much less likely that we'll get these working than we will some of the other potential solutions. There is an interesting article here about the promise of, and problems with, thermal depolymerization.
     
  12. Apr 14, 2008 #11

    mheslep

    User Avatar
    Gold Member

    As long as you are speculating, why not? The reality is you can't use fusion anywhere for energy production now, and likely not for some decades yet.
     
  13. Apr 14, 2008 #12
    Thrust is one thing. But the units to compare are Power times Duration per Mass of power plant, power storage facilites and the fuel itself.

    It's hard to beat the condensed liquid energy from petrolium. Half of the energy source you don't even have to carry around or pay for. It's the air the plane flys through. It mixes efficiently with it's oxidizer--you don't have to shovel it into the airplane's fire box to use it.

    I think if you ran the numbers, electric propeller driven airplanes would come in a far, far distant second place. They would run so far behind practical, to be only be an expensive toy.
     
    Last edited: Apr 14, 2008
  14. Apr 15, 2008 #13
    Loosing a fee lunch when you're hungry isn't something you normally wink over, as will become obvious, to even the most ardent, soon enough.

    The general idea of converting organic matter to hydrocarbon based fuel has solidified around the term "biogenesis."
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: How will fusion solve all the world's energy problems?
  1. How to solve a problem (Replies: 22)

Loading...