At the end of the day, I guess which fuel wins will be primarily about EROEI - unless I get most energy out for the energy put in, guess most folks are not going to be interested in whatever the feedstock is - algae, cellulosic biomass, jatropha, whatever...

It's in this context I'd like to get an approximate EROI (energy returned on energy input) for algae biodiesel and algae ethanol. I came across some numbers like 5:1 for both, but I'm not entirely sure about the authenticity of the data presented...

Any inputs will be welcome

I have read that it is about 3.2:1 for algae Biodiesel. For ethanol it is about 1.2:1. I'm also not sure about the authenticity of the data.