[ineedasername]

I mentioned composting: Composting produces significantly lower amounts of greenhouse gasses compared to simply letting the food decompose in a trash heap: https://www.sanjoseca.gov/home/showpublisheddocument?id=198

[AstralStorm]

And if you do it very well, you can recapture almost all emitted methane, using it as an efficient fuel in fuel cells. (Preferably, rather than just burning it.) It's a very clean source.