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Helium Leads to Geothermal Energy Resources

Roland Piquepaille writes "When we think about alternative sources of energy, we often forget the potential of geothermal energy resources. In fact, it has been estimated that accessible geothermal energy in the U.S. represents 90 quadrillion kilowatt-hours or 3,000 times the country's total annual energy consumption. So far, it has been difficult and expensive to locate good sources of geothermal energy. But now, two U.S. researchers have found a new method which doesn't require drilling. They are using the ratio of helium isotopes in surface waters to point to the best sources of geothermal energy."

3 of 317 comments (clear)

  1. Actually Canada is the number one supplier of Oil by phunster · · Score: 5, Informative

    Actually Canada is the number one supplier of Oil to the U.S.

    Source: http://www.eia.doe.gov/pub/oil_gas/petroleum/data_publications/company_level_imports/current/import.html

    Energy Information Administration: Official Energy Statistics from the U.S. Government

  2. Re:As a Non-Expert by Zobeid · · Score: 5, Informative

    From my own reading on the subject, "the major roadblock to widespread geothermal use" is lack of motivation.

    Despite all the talk and hand-wringing over global warming, power companies are still not paying any carbon tax. They aren't required to phase out coal-fired plants, and they aren't having any difficulty getting permits to build new ones. They have a business model that is working and making money for them, and no pressing reason to change their ways.

    A study came out of MIT a while back showing that the USA has vast geothermal resources which could be exploited fairly easily. It would require a small R&D investment to prove the concept, but they believe enhanced geothermal energy could be accessed across large regions of the country.

    Is anybody going for it? No. . . No power companies want to pony up that "small R&D investment". Why should they? They can continue using coal and natural gas without any R&D cost at all. As for the federal government, their energy research has been cut to nearly nothing. So nothing happens.

  3. RTFA by MillionthMonkey · · Score: 5, Informative
    ...since pretty much all of Earth's helium results from alpha decay of radioactive metals.

    So?

    Different parts of the Earth are composed of a variety of elements in varying amounts. Earth's crust contains a variety of noble gases, one of those being helium. Natural helium occurs as two isotopes, helium-4 (4He) and helium-3 (3He.) Typically, helium-4 is more abundant in Earth's crust, whereas helium-3 is more abundant in the mantle below. Thus, the helium-3/helium-4 ratio of the gas found in groundwater can provide an indication of the extent to which the water has interacted with volcanic rocks derived from the mantle.
    Most helium in the crust has escaped to space. The helium profile in the crust is dominated by steady-state production of helium-4 by alpha decay. This is mostly the case in the mantle as well but the mantle has some reserves of primordial helium which never escaped to space because it's buried more deeply, and that helium has an isotopic signature that includes helium-3 (the new helium from radioactivity is all helium-4). They're looking for the helium-3 using the helium-4 as a baseline.