Looking at that Wikipedia page, the composting toilet sounds rather more complicated and expensive. Also potentially it does not destroy pathogens completely. The approach of the "Loowatt" keeps the residential installations simple, sanitary, and inexpensive, and locally centralizes the composting in a process that uses high heat to completely eliminate pathogens.
This. Sometimes decentralized solutions are great, but most people don't want to become experts at the sanitary biological processing of human waste (especially inside their own home). For safety and efficiency reasons it makes sense to aggregate that at the community scale. Think of it like the local sewage treatment plant.
Actually it's better than a conventional sewage treatment plant, because
* it safely recycles fertility (interrupting the fecal-oral route, unlike "night soil"), providing a sustainable alternative to phosphorus mining and other fossil fertilizers
* it doesn't discharge fertilizer into waterways where it causes eutrophication and "dead zones"
* it produces biogas energy rather than being a large energy consumer
* it doesn't squander potable water to transport human waste, and
* it doesn't require a huge network of underground pipes, which have enormous embodied energy and replacement cost. If your city can't afford to replace the underground pipes, your water system is insecure and unsustainable for that reason alone.
Yeah those are good points. Also I realized that we have a "subscription service" with indoor plumbing through paying for water. There's no reason something like this couldn't be paid for through a tax which would encourage wide scale adoption.
