[SGVLUG] OT: Biofuels energy content: Methodology Dilemma

David Lawyer dave at lafn.org
Wed Dec 27 23:13:06 PST 2006


I previously stated that I would look into the question of fossil fuel
energy embedded in biofuels.  I've not done any of this except look
into the methodology of energy accounting.  A book I recently borrowed
on interlibrary loan is "Environmental Accounting, Emergy ..." by the
late H. Odum.  It's emergy with an M instead of N.

Sad to say, the methodology situation is in total disarray.  In this
book 2 methods are shown to account for the human energy used to
produce goods and services.  One method (metabolic energy) assigns
2,500 kcal per person-day;.  Using total energy (including the energy
one uses up in housing, food production, transportation, recreation,
etc.) it's 231,000 kcal per person-day, almost 100 times larger.  But
some may just use the additional metabolic energy that one exerts in
production and this might be say only 500 kcal/day.  So now the two
extremes of accounting differ by a factor of 500.  I've thought about
how to best account for human energy which results in something
in between the two extremes.  So I'm now trying to see if anyone else has
come up with some of the same concepts  If not, I should try to write
about them.

I don't think emergy is clearly defined in this book but I don't want
to go into that problem.  It's something similar to embedded energy.

Since Linux is mainly the product of human effort, it must contain a
high amount of embedded energy (emergy ??).  How would one allocate
that energy to the the users of Linux (including allocating it to
goods and services produced with the aid of Linux)?

			David Lawyer


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