| The depletion of petroleum will require fuel substitutes that can prolong rising energy
demands. Fuels can be produced using biological commodities; these are called
"biofuels." Some examples of biofuels include ethanol extracted from sugar cane (a
common gasoline substitute) or oil extracted from canola seeds, which can be
converted to biodiesel. Biofuels should be pursued to produce a more
environmentally friendly energy source, help meet today's energy demands, and help
society meet future energy demands. Still, the energy must be used sustainably and
effectively. To meet such requirements, biofuels programs should be designed with
respect to location, which was demonstrated through the analysis of three different
case studies: The United States, Spain, and rural Fiji. In addition to locale, for biofuels
to be successful, population growth must be controlled. While the second derivative
of population is negative, the first derivative of population is positive and is expected
to grow. In addition to population dynamics, it is essential that society strives for energy efficiency to significantly reduce energy requirements that will allow biofuels
to be more effective.
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