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How much of the various fuels is there on Earth

  1. Jan 12, 2007 #1
    For instance, how much petroleum? how much plutonium/uranium? how much coal?

    I don't expect exact numbers, just estimates. Even better would be time-estimates of how much longer we can have electricity.

    And I'm aware of the president's goal to achieve fusion energy by 2050 or something. Further information would be well received.

    o| Hiram
  2. jcsd
  3. Jan 13, 2007 #2
    Nobody can give you a straight answer. Actually there's a lot of oil and gas and other things, but that isn't the important thing, they're only useful if we can get to them and the energy we spend getting them out is less than the energy returned after all is said and done. Economics.

    The fact is there's a lot of energy from things like the sun and the wind and even the tides so we're always gonna have electricity at our disposal. One thing seems fair to say though, if our population continues to grow along with our energy demands, unless we develop new sources we will not have enough to continue our consumerist ways. That is, we'll still have electricity but we won't be able to use it as much anymore.
  4. Jan 13, 2007 #3


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    Staff: Mentor

    Estimates on range from 20-100 years (give or take), estimates on coal range up to a couple hundred years, and Uranium or other nuclear fuels (plutonium is not naturally occurring), essentially limitless.
  5. Jan 14, 2007 #4
    Natural oil is more dynamic measuring the rate of consumtion against the rate of discovery of more sources. The outcome of this highly variable process is a surprisingly constant rate of about 30 years.

    A very important potential source of energy is rather unknown, the methane hydrates of the ocean floors, especially some accumulations on the deposit fans of major rivers like the Mississippi and Amazon.
  6. Jan 14, 2007 #5
    Thanks for the interesting responses, everyone.

    russ_watters: When you wrote "limitless", you don't mean the remaining 5 billion years until the Sun fuses itself out, do you? It must be less than that...
  7. Jan 25, 2007 #6
    The amount of fuel there is, is not just an 'inexact' figure (as in determining the rough quantities in earth's soil), you must think in economic terms, that is the costs for exploiting those minerals or resources come into question, always.

    Most figures or estimates you find, are about resources which are economically exploitable under current prices and techniques.

    The figures can be inexact as that there are indications that Middle east oil resources (an economical figure) have doubled at some time in the past.

    Either those oil producing states have just fantasized they have more oil then they originally estimated, or they have made economic calculations on what oil can be exploited at what price level, and since oil prices steadily rise, they may increase their resources.
  8. Jan 25, 2007 #7
    Or use it in a more economical way.....

    Most of your energy for warming houses is simply wasted. Only a fraction is used to increase the temperature of the air in your building, the largest part is necessary to compensate for the loss of energy due to losses (the temperature gradient with the outside atmosphere).
    So we might very well focus on techniques on how to keep the energy in and prevent the heated air from cooling down quickly.
    In that way, we are gonna need less energy, but with the same benefit.

    Energy reduction/transition is a three way path:
    1. Reduce the energy that is not used at all: heating your house when you are away, or all kinds of electric equipment that is consuming electricity without you using it.
    2. Increase the energy efficiency in all energy transitions (from producing the electricity or fuel source to distribution and utilization). Also to regain energy from waste energy.
    3. Transition from fossil energy sources to renewable energy resources. If you have done the first two steps extensively and exhaustively, there is less energy you have to produce to fulfill your needs, which then can be more easily replaced with all kind of resources (from water, geothermic, wind, solar, biofuels, etc.).

    {The most common rebuttal that 'alternative energy sources' like water/wind/solar etc. can't fulfill all our needs are typically based on energy usage statistics which don't take into consideration the need of steps 1 and 2.
    We can't replace fossil fuel usage with any other resource (unless we would have nuclear fussion, but that is still a long way, and not sure) , unless we extensively also take care of step 1 and 2.
    Alternative / renewable energy is available in magnitudes of quantities larger then the current world enery consumption, but most of it we can not tap into, but if only that part would be used that would be achievable, this could fulfill all energy needs.
    As an example: if we cover an area the size of France with solar panels, this would give us the equivalent of energy the world currently uses. }
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