It's a good idea to read all studies before taking one study's
conclusion as fact. Negative biodiesel production is a myth being
propagated by those against it. I think you'll find varying results
depending on the source and funding of the study (that goes for
petroleum fuels production as well). For instance, some studies report
biodiesel figures of well over three units produced per one used. If you
consider oil production primarily for SVO usage, that figure is far
higher. There are thousands of folks using SVO successfully, guess it
must not work because someone on a website says it won't. Haha. Number
one using SVO was Rudolf Diesel, guess his engine never ran successfully
on peanut oil either, hmmm.....

Karl

Mike S wrote:
> At 01:04 PM 6/26/2007, Karl Mullendore wrote...
>> One should also take into consideration how much energy goes into the
>> production of gas and diesel from petroleum
>
> Gasoline production is about 86% efficient (~1 unit of energy used for 6
> produced as final product), diesel refining is about 91% efficient (~1
> unit of energy used for 10 produced). Source: "Allocation of Energy Use
> in Petroleum Refineries to Petroleum Products"; Michael Wang*, Hanjie
> Lee and John Molburg; Center for Transportation Research, Energy Systems
> Division, Argonne National Laboratory, table 5; -
> http://www.transportation.anl.gov/software/GREET/pdfs/IJLCA-2004.pdf
>
> Also interesting is figure 4, which shows that "well to pump" diesel
> production produces about 20% less greenhouse emissions than gasoline
> production.
>
> Contrasted with _negative_ production efficiency for current biodiesel
> production, which has already been cited (e.g. 5 units used for 4
> produced with soybeans, much worse with sunflower). No figures have been
> cited for algal oil.
>
>> Some oils, and I believe the algae oils may fall into this category as
>> well, can be used directly after filtering, no biodiesel conversion
>> process necessary.
>
> Not according to the sources you provided: "The major problem associated
> with the use of pure vegetable oils as well as oil from algea as fuels
> for diesel engines is caused by high fuel viscosity.." -
> http://www.oilgae.com/algae/oil/biod/prod/prod.html
>
>