It bothered me at first, but I think it's about greenhouse gas emission. For example, methane is another power source, with legal restrictions depending on the "cleanliness" of the gas when burnt. I don't remember whether biofuels are still used at the time of the story.
That still doesn't make sense-- if the food stocks were created without mining carbon from oil or coal, then they're carbon-neutral.
There was a recent discussion considering the idea of a monthly Book (later expanded to movies, links, etc) thread. The poll was pretty unanimous (Both before and after I was karmassassinated) that this was A Good Idea (tm), and daenerys's Janurary thread (from which I obviously stole a lot of this) was fairly successful, so let's see if we actually need one per month.
Post what you're reading or watching, and your opinion of it. Post recommendations to blogs. Post whatever media you feel like discussing!
Rules: