[knownothing]

> Actually, I wonder how much this will last considering that fossil energy will likely cost more and more and that more and more people from developing countries start to travel too.

When I was flying back from Paris, I sat next to an Airbus engineer who was working on retrofitting jet engines to run on a biofuel produced via fermentation rather than normal fuel.

No clue how far along that project is or how promising it is, but there are folks in the industry thinking about this problem.