Might future ships run on…seaweed??
This paper in the journel SCIENCE reports on discovery of a process that uses a genetically engineered e coli bateria to metaolize sugars in seaweed to achieve a .281 weight ethanol/weight of dry seaweed (macroalgae).
The question is, can sufficient seaweed be harvested to make a dent in fuel prodution. Might not solve the energy challenge writ large, but seaweed aquaculture off of major ports could provide supplemental fuel for Navies. the question would become how large an aquaculture enterprise would environmental concerns allow?