I was using a different site: http://hypertextbook.com/facts/2003/RoxanneGarcia.shtml
http://hypertextbook.com/facts/2005/JennyHua.shtml
26.8 MJ/kg vs 20.16 MJ/kg = 1.329x the energy by weight.

Perhaps using the energy per volume is more appropriate when using ml and oz. of liquid for stove testing? smile In that case your figures make more sense.