As listed in the milennium goals, basic sanitation is a big challenge for developing countries. With an expected population boom in Africa and Asia this remains an issue and an urgent need for technology and new products to raise sanitation standards. Needless to say, the amount of water used in 21st century toilets should be absolutely minimized. The new mega-cities in developing countries cannot put all the city dwellers on the sewage system. So future toilets could provide an answer to many, many problems.
Toilets could be designed to recycle nutrients that are in our food and ‘flushed away’ in the toilet. Potassium is one of those nutrients, which is absolutely vital for agricultural production and becoming scarcer in the next century. Also think of the energy that faeces could provide, when released in a sophisticated way. Grietje Zeeman, professor at Wageningen University is dedicated to design new sanitation systems to recollect resources to the maximum. Vacuum toilets and a vacuum system to collect organic kitchen garbage, could be part of that. She has already demonstrated this closed cycle system in a neighbourhood in Sneek, the Netherlands.
The potential of toilet design has also been recognised by the Bill and Melinda Gates foundation, who has selected eight universities to develop prototypes for the Toilet of the future contest. The winning toilet by California Institute of technology re-uses water and turns urine and feces into fertilizer for crops and into hydrogen that can be used as a backup energy source. It even runs on solar power! Second place winners, Loughborough University came up with a design of a toilet that turns excrement into charcoal. The third place went to the University of Toronto who came up with a toilet that treats excrement and recovers resources and clean water. TU Delft’s toilet design uses microwave technology to convert human excrement into gas which is then fed to a fuel cell. All in all, the Bill and Melinda Gates foundation gave a huge impulse to the design of toilets that are needed for the growing populations of the 21st century.
If these types of toilets would be installed on a massive scale, and if the whole sanitation system of cities is adapted to the need to recollect natural resources, then this could have a tremendous impact on city live in the mega-cities of Asia and Africa.