Here's a dose of reality...
1) This is a research project
2) You're not drinking the bio fuel so the question is do you really have to wait until the crop matures
3) The study was done in Sydney, right? While Aussies are thinking outside of the box, Agave is grown in Mexico. In fact Te-kill-ya is only Te-kill-ya if it is made from the Agave grown in Mexico.
4) Agave grows in dry climates. Tree Huggers will like this because unlike man made solar plants in deserts, its 100% natural and would have a lesser impact on the environment.
5) Wasting lifestyle? Stop 3rd world nations from over populating the world and creating human bio-mass.
6) Want clean cheap energy? GO NUCLEAR.
That's your reality. Nuclear power is the clean cheap and most efficient source of power. That is, until you have fusion energy which is still yet another 50 years away.