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

Geothermal energy

  1. Nov 30, 2007 #1


    User Avatar
    Gold Member


    Helium isotopes point to the best sources of geothermal energy
    Unknown to most, the US has enough geothermal energy below its surface to supply three times the amount of energy that the US consumes annually. Up until this point no one has tapped this source because finding the geothermal hot spots is too expensive. Recently researchers discovered that surface indicators can predict if geothermal energy sources are below the ground -- now no more expensive drilling is required.
  2. jcsd
  3. Dec 2, 2007 #2


    User Avatar
    Gold Member

    I see no one has disputed the above, so what is the problem, why are you not drilling away like crazy?
  4. Dec 2, 2007 #3


    User Avatar

    Staff: Mentor

    I'd like to see the math behind the "3000 times" (not three times) claim. That's an awful lot. Regardless, the article doesn't actually say anything about geothermal's viability in the US. It doesn't sound like they've actually tested the method and it doesn't say how far you have to drill. It's an interesting litte research project, but it isn't something that would cause people to start "drilling away like crazy."
  5. Dec 3, 2007 #4

    jim mcnamara

    User Avatar
    Science Advisor
    Gold Member

    This is not my discpline, but I see the same stuff in areas I do know - 'why don't we<...>'
    questions based on one paper from one researcher.

    <...> is usually pretty much in this order:
    'cure cancer'
    'stop global warming'
    'create eternal life'
    'cure aids'

    The assumption you should make, which russ made without mentioning it: 'am I so much more informed on this subject than the 500 PhD's in the field who read the study before me'? Most of the time you should assume 'I am not'.

    And in many case these unseen experts are doing one or more of these without our help:

    1. pursuing it like crazy, getting investors, etc.
    2. doing nothing because they know better
    3. waiting for better data, or better more conclusive studies.
    4. doing some research on their own

    Drilling's expensive ya know. And there really is no global conspiracy preventing a geologist from becoming the Bill Gates of Geotherm, Inc. The people at eurekalert.org ought to know better too.
  6. Dec 3, 2007 #5


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2016 Award

    "It has been estimated that within the continental United States, there is a sizable resource of accessible geothermal energy – about 3,000 times the current annual U.S. consumption." --- Nikki Staab, MEDIA CONTACT, ASU. What's the source of the estimate? Integrate the temperature gradient from earth surface to a depth of 2-3 km and multiply by 4MJ/(m3K) over 107 km2; the qualification regarding quality of the energy (99+% at less than 20 K above ambient, or, useless) is omitted.
  7. Dec 3, 2007 #6


    User Avatar
    Science Advisor

    Does that assume removing all heat from the rocks underneath the entire landmass of the continental U.S.? I'm sure much of the world would applaud such a plan, but I cannot endorse it myself.
  8. Dec 5, 2008 #7


    User Avatar

    Staff: Mentor


    Google is funding research in Geothermal Energy

    Engineered Geothermal Systems (EGS)
    Hot Dry Rock Geothermal Energy Technology

    The Future of Geothermal Energy
  9. Dec 5, 2008 #8


    User Avatar

    Staff: Mentor

    So they are now hoping to get in on alternative energy sources eh? They certainly have enough capital.
  10. Dec 5, 2008 #9


    User Avatar
    Gold Member

    The figure of 3x the USA's energy use is a bit suspect for me. How do they work that out? Is that the total heatflow for the whole continent? It reminds me of the often heard statistic that the earth recieves enough sunlight in x minutes to power the world for a year. True, maybe, but there is no way at all that it will ever be possible to tap all of even most of that energy.
  11. Dec 5, 2008 #10


    User Avatar

    Staff: Mentor

    It's part of Google's initiative on renewable energy.


    They have other areas. In fact, they have an engineering and technology team.
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Geothermal energy
  1. Clean energy? (Replies: 19)