I think I have a better solution--what if we train the pigs to "plug" themselves into a gas recovery system, kind of like self milking cows, when they need to release?
Pigs are real smart, you know.
But then again, pigs floating around in the atmosphere would provide additional radiation shielding, and if we tether them, after awhile you would just have to reel one of them in to enjoy some barbecued spare ribs.
Two responses: One; what I was trying to say was ... Global Warming = When Pigs Fly
And secondly, we are already working on a system of creating herbivores that convert biomass into combustible fuel. Oddly enough, they too will fly. -- We call them "Dragons."
Sometimes I walk into the most unusual conversations. LOL!