What they’re not saying is that this helps put bioavailable nitrogen and carbon back into the soil, reducing dependence on chemical fertilizers, which come from fossil fuels. Compost is a valuable resource, particularly with more people deciding to source their food closer to home (it’s bulkier than chemical fertilizers to transport). And at scale, it’s probably a lot cheaper in terms of direct costs (no social cost of carbon added), but I don’t know for certain. (I’ll look it up or run the numbers.)
Parisians converting food waste into compost
Marcus James Thomson, Ph.D. 