These are great questions. Perhaps we should try to work through
these as a group in more detail during the spring semester. Here's
my two cents:
I think it is probably fair to conclude that familiar industrial
agriculture crops are not a sustainable alternative energy answer
for many of the reasons you suggest. Plants that are naturally
productive and do not require such intensive irrigation and
fertilizer inputs (most of these plants are often thought of as
"weeds") would clearly seem to be a more promising alternative.
Also, as a recent posting suggested, technological and/or
regulatory advances that significantly ratchet down consumption of
fuels (i.e., greatly improved fuel mileage for cars) are an
absolute necessity if we're serious about reducing greenhouse gas
emissions or just about anything else having to do with
I think one issue you raise that I can address in some detail is
the carbon effect associated with the utilization of bio-waste
material. While it is true that CO2 is released through
combustion, the carbon released through this process was, in
principle, fixed in recent times through biological activity.
Thus, no "new" carbon is being introduced into the atmosphere
through this process - in essence, carbon that is already part of
the global cycle is being recycled. Of course, carbon is not being
permananently sequestered out of the global cycle through this
process, either. Therefore, bio-waste utilization is often
referred to as a "carbon neutral" process.
By contrast, the burning of fossil fuels literally introduces new
"fossil" carbon into the atmosphere. The advantage of bio-waste
utilization over fossil fuels in terms of greenhouse gas emissions
fundamentally boils down to the idea that it is a carbon neutral
process, as opposed to a carbon loading process. The advantages
are even higher when dealing with human and/or animal wastes,
principally because large amounts of fossil fuels are often used
in traditional wastewater treatment. Utilization of these wastes
not only produces carbon neutral energy, but also eliminates most
of the fossil fuel energy used for wastewater treatment. In
addition, efficient recycling of nutrients such as nitrogen and
phosphorus contained in these wastes has further greenhouse gas
benefits because less fossil energy has to be expended for
production of fertilizers.
Hope this is at least somewhat helpful. Happy holidays to
Ph.D. Candidate, Interdisciplinary Ecology
School of Natural Resources and the Environment
University of Florida
(352) 466-4549 - home office
(352) 328-1199 - cell
BioEnergy and Sustainable Technology Society
On Thu Dec 21 01:18:47 EST 2006, "MARTIN,ELIZABETH J"
<[log in to unmask]> wrote:
> To anyone willing to address my question:
> I was wondering if someone would mind directing me to some
> information regarding the pros and cons of biofuel vs. petroleum
> in terms of land use and water consumption.
> While I fully agree that there is a dire need to reduce reliance
> on petroleum and other non-renewable resources, I am concerned as
> to how it balances out on the other end of the spectrum.
> Currently over 1 billion people do not have access to safe
> drinking water, resulting in millions deaths every year due to
> unsafe and unsanitary water conditions. The main problem is the
> agricultural techniques used to produce crops such as corn,
> wheat, soybeans, etc. The largest problem is the net loss of
> water and the destruction of land due to irrigation. From what
> I?ve been reading, it appears that the main alternatives to
> petroleum lie in the use of these organic materials as potential
> fuels. So my main point is this, even if biofuels replace
> petroleum and reduce green house gases and air pollution, won?t
> the result be an even bigger problem due to water scarcity? I
> understand that no one can know if this will even be a problem,
> but I can?t help but wondering if biofuels are the answer, or if
> they are a catch 22.
> I also have a slight problem with the burning of natural and
> human wastes. While this does eliminate the growing problem of
> landfills and the release of methane gas into the atmosphere,
> isn?t it still slightly retroactive because combustion of any
> material releases carbon dioxide?
> I'm terribly sorry if these questions seem ridiculous or
> completely off base, but I'm having trouble finding answers.
> Incase anyone was wondering where I got my information on water
> There is also a very informative article available at:
> Click running.pdf
> MARTIN,ELIZABETH J