E. Lowe mentioned:

The ability to use renewable  bio
fuels and thus contribute zero to global warming tips the balance.
Biofuels don't have to come from subsidized soybeans.

So I tossed in my tinke-tinke:

Seems to me the global war-ming is caused by excess greenhouse gases, CO2
being the most significant.  Diesel cycle engines produce CO2 as an exhaust
component in approximately the same quantity per stroke regardless of the
fuel source D1,D2, McDooDoo or Chik-fil-a or soybean oil.  I fail to
understand (my usual excuse) how using "organic" "free range" "home grown"
oil sources would significantly affect the CO2 fraction of the exhaust gas.

pensioner