Innovative system turns human waste into sustainable fertilizer Stanford ReportResearchers using biochar to help farmers, clean water, power cars Auburn UniversityFertiliser separating system could usher in a urine revolution cosmosmagazine.comPrototyping and modelling a photovoltaic–thermal electrochemical stripping system for distributed urine nitrogen recovery NatureLiquid gold: Prototype harvests valuable resource from urine Tech Xplore