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

Harnessing the power of our planet.

  1. Nov 18, 2006 #1

    taylaron

    User Avatar
    Gold Member

    ok guys,
    we've been fiddiling and fuming about all this nuclear reactors for the past few generations right? when all they essentially do is produce heat.
    this heat drives a turbine which in turn produces electricity
    ta da!

    as we all know, nuclear reactors can pose a very dangerous threat to the environment if not dealt with properly. but we still end up with all the radioactive waist which is really a big downside.......

    why dont we use another source of heat that we dont need to "create"
    we have at our disposal right underneith our feet some sereous heat!

    what if we build a thermo-electric generator underwater, where the crust is thin.,
    i know this has some sereoulsy technical diffuculties.

    or even better, wat if we use these areas on our earths crust that are underwater and essentially build a hollow tube that submerges underwater toward all this heat.
    all this heat (esentially lava and such) would mealt the water that is right above it (no need to worry about how much water you need)
    i say you use this pipe and esentially guide all this steam up to the surface . but the real beauty of this idea is that, because you are putting all this "air" into a pipe that is underwater, and is open at the end. all this air rises through the tube right? but of course it builds up pressure at the top because the turbine is up top. because the water would want to reach equalibrium inside the tube and outside, you just need to get some air in that tube, and leat it build pressure.
    then with your turbine, you open the valve that is over its intrance where the pressurized air is, and generate electricity.
    although the generator cant be really big because you dont want too much air to escape at one seccond as to lose too much pressure within the tube. the exit flow of air must be less or equal to the ammount of air coming in from the bottom (under water)
    all this so you still have some pressure to work with -to drive the turbine-


    a picture would be so much more usefull to describe this.
    sooooo......

    what do you think or am i just insane?
     

    Attached Files:

  2. jcsd
  3. Nov 18, 2006 #2

    Danger

    User Avatar
    Gold Member

    With apologies, I'm way too inebriated, plus Lucy (cat) is not only doing my typing for me, but also trying to lick my face while I proof-read, so this is going to be brief. I didn't actually read your entire post due to the beer, but geothermal energy is definitely a worthwhile endeavour. The only problems that I know of involve access (either physical or political) to the sources, and the efficient distribution of power from those sources once they're developed. I'll take another look at your post tomorrow, when I might possibly be sober, but your best bets along this line are probably Russ, Fred, Integral, Clausius, Brewnog... maybe Zoobie. It's not something that I have a lot of knowledge about.
     
  4. Nov 18, 2006 #3

    russ_watters

    User Avatar

    Staff: Mentor

    That technical difficulty is beyond serious. Iceland essentially gets its geothermal power from the mid-atlantic ridge, but for us, the mid-atlantic ridge is 12,000 feet under water and 2,000 miles offshore.

    It just isn't accessable to most people.
     
  5. Nov 18, 2006 #4

    berkeman

    User Avatar

    Staff: Mentor

    I don't think it's insane, just very challenging. And when you get right down to it, in a few hundred years we're going to be looking for renewable (or very very large) sources of energy, and there are only a few possibilities. Solar is one, and variations on geothermal and water power and wind power are others.

    To harness geothermal in the manner you are suggesting, we need to get better at deep drilling and well maintenance. I'd encourage you to research the state of the art in drilling technology, and see if you can contribute in some way. Drilling for oil and gas obviously drives the current state of the art, and if you can contribute, your initial contributions would probably be with that focus. But if you keep your vision of very deep geothermal drilling in mind, you could definitely help invent the technologies that would be necessary for deep-hole power plants.
     
  6. Nov 18, 2006 #5

    berkeman

    User Avatar

    Staff: Mentor

    Glad that you clarified about Lucy being a cat, Danger. :blushing:
     
  7. Nov 19, 2006 #6

    taylaron

    User Avatar
    Gold Member

    thanks for you imput guys. i'll have to keep this one in mind.
    obviously this design isnt pratical in this stage of technology.
    but in the future, i think thermal power is going to be a big one for us.
    regarding the drilling.........--> why drill bits?
    i know this sounds like its out of a sci-fi book or movie, but why not high powered optical devices or sound waves??
     
  8. Nov 19, 2006 #7

    Danger

    User Avatar
    Gold Member

    Niether of those technologies are practical for such applications given current state-of-the-art. There are simply too many problems with such things as beam occlusion, energy dispersal, etc.. I wouldn't rule them out in the future, but an awful lot more development is needed before they can be useful on that scale.

    edit: I should mention as well that there is an awful lot more to drilling than just making a hole in the ground. Multi-section bits provide pumping action and mud circulation for lubrication, help support the walls of the hole, and can be manoeuvred for angled or even horizontal penetration. It's a very well-developed science that will be hard to replace.
     
    Last edited: Nov 19, 2006
  9. Nov 21, 2006 #8
    There are a number of small scale geothermal units around the world. The process basically requires two bores connected at the bottom to form a U shape. Water is pumped down one heated at the bottom and raised up the other.
    You can do this anywhere with quite shallow bores but you end up with a lot of low grade heat that is difficult to convert to power but is useful for heating your house.
    To generate electricity you really need steam and the steam depth is just too deep in most places. It can be done at natural fault lines but these often have volcanic rocks granites and basalts that are very difficult to drill through.
    I know of one scheme that was installed in Cornwall which provided sufficent power to run a house and enough waste heat to warm a medium sized commercial greenhouse.

    Reality is that economics kills most renewables. By the time you come near to paying back the installation cost of small scale geothermal, solar or wind turbine projects the equipment has worn out and needs replacing so your just paying for your power up front.
    Therefore these schemes are only suitable for people who can afford to have a moral outlook, personally I have a Mortgage and Family instead so I'll have cheap coal power.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Harnessing the power of our planet.
  1. Chip Harness (Replies: 17)

Loading...