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Nonrenewable Energy Resources

By Arlon Staywell
Test Your Knowledge
    If there are about 452 million acres1 of farmland in the United States and if each acre could produce 125 bushels2 of corn per year and each bushel of corn could produce 2.65 gallons3 of ethanol and the United States used 139 billion gallons4 of gasoline in 2005 what percentage of the farmland would it take to produce in a year as many gallons of ethanol as gallons of gasoline used in 2005?

Click here for answers.

RICHMOND 2005 — Many are concerned how much fuel we might need from renewable sources and how much of the available farmland would it take to meet our needs.
    Of course some acres are better than others and in any given year some will get better weather than others and there are many varieties of corn suitable to different conditions.  There is no detailed, comprehensive survey of all the factors.  These are just very rough estimates.  Research continues to find a variety of corn and method of extracting ethanol that will be more efficient.  Some intelligent, informed people will give you different numbers than these with which to work.
    Still in any case there is something many of you know and none of you should doubt and that is the current U.S. economy depends heavily on nonrenewable energy sources.  Nonrenewable energy sources are crude oil, natural gas, coal, nuclear and other fuels that cannot be replaced. There is a certain amount of them on the planet and when they are used up there will be no more.  It might be more accurate to speak of nonrenewable levels for consumption.  Supplies of some of these fuels can be replaced by nature, but it took millions of years to create the current supplies.  Although they are "renewable" they are not at any significant levels for consumption.
    While ethanol is indeed renewable, from corn crops for example, much of it used today in industry is from the ethylene in crude oil which is nonrenewable.  State requirements for a percentage of ethanol in gasoline might create the illusion that the country is producing more renewable fuel than is the case.  The requirement is not intended to do that.  It is intended for less pollution.  Still some might get the impression there is more renewable ethanol than in fact there is at a time.


    And the economy is likely to expand.  As the population expands the number of farmable acres goes down and the consumption of resources goes up.  That means the dependence on nonrenewable energy will become much greater.
    There is much debate how soon nonrenewable energy sources will run out, but there is no debating that they eventually will.  At that time we will be forced to operate the economy at a sustainable, renewable level.
    There is significant optimism that improvements in technology will continue and that the possible renewable level of consumption will become higher than it is today.  That amounts to spending money we don't have.  Unless those improvements come there will be significant economic and social crisis when the United States hits the nonrenewable energy source wall.
    Too many very young people seem to hope we will get much energy from the hydrogen and oxygen in water.  Yes, water contains hydrogen and oxgen chemically combined, but the energy used to separate them out is the limit of the energy you can get back, as you should learn in high school chemistry.

© MMVI by Arlon Ryan Staywell

      1  Based on data for "arable" land from "Time Almanac 2006"  (published in 2005)
      2  Numbers vary considerably in practice and theory. Record yields in optimum conditions can be much higher. This is an educated guess at an average. See the answer for more details.
      3  Estimates found ranged from 2.5 to 2.75; the figure 2.65 is from a Monsanto website.
      4  Based on data from the Energy Information Administration, United States Department of Energy

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