The third photo is fascinating and macabre, the hay bundles look like the plastic bags used to hold corpses in my dissection room in the university (I am a med student) and it makes a strong impact between the actual sunny and cheerful scene and the memories it rises in me :(

regarding biofuel - I think that science should develop methods to use industry leftovers and home waste in an ecological way to produce fuel, since this waste will be created anyway, we should use it! there is some info in this MIT article:
https://www.technologyreview.com/s/413606/converting-garbage-into-fuel/

But - the methods you prefer are surly the best ones ecologicly because they make almost no harm to our dear planet. what should be considered is whether they can be used big scale and provide masses and masses of people. interesting :)

thank you for an interesting, thought provoking article and lovely photos!