Science Daily titles their post New Toilet Turns Human Waste Into Electricity and Fertilizer; It's based on a presser from Nanyang Technological University titled NTU’s new loo turns poo into power. Neither is accurate.
What the scientists from Nanyang Technological University are standing around is a urine separating toilet that uses a vacuum to evacuate it instead of water. All you get out of this is urine and poop, much like you do with the Swedish No-Mix toilets
What matters is the whole system, what they do with it. The scientists at NTU have connected it to a vacuum system, like those used in airplanes or in the Roedigner No-Mix vacuum separating toilet, described our post Waste Not, Want Not: The Future of Toilets
Vacuum toilets use a fraction of the water of conventional toilets, needing just enough to clean the bowl. Minimizing the use of water makes it easier to deal with the poop and pee at the other end. The project leader notes:
Having the human waste separated at source and processed on-site would lower costs needed in recovering resources, as treating mixed waste is energy intensive and not cost-effective,” Prof Wang said. “With our innovative toilet system, we can use simpler and cheaper methods of harvesting the useful chemicals and even produce fuel and energy from waste.
The urine goes to a processing facility where they convert it into fertilizers, like they do in Sweden. The poop is sent to anaerobic reactor where it is digested to make methane, like they do in Boston, Vancouver, California and Uganda. The methane can be converted to electricity.
As one Swedish researcher noted, "Don't mix what God separates". Poop without a lot of water or urine makes for " richer sludge and produces more methane, which can be turned into gas or electricity". We are approaching Peak Phosphorus and will need all the fertilizer from pee that we can get.
The NTU scientists have put it all together in the kind of complete system that should be used everywhere. They've got $10 million to build a demonstration project, which is wonderful. The world needs this.
What the world doesn't need is to think that they have invented a new magic toilet. They haven't.
The History of the Bathroom
This is a subject dear to my heart, I was going to write a book on it; instead I did this series. The important thing is that the toilet is just a small part of the system, the human interface.