The “diversion” toilet needs no sewer and no outside energy source and is cheap to operate.
It was developed by a team from the Swiss Federal Institute of Aquatic Science and Technology (Eawag) and the Austrian design firm EOSS.
The team beat out submissions from 21 other universities and research facilities to win the “Reinvent the Toilet Challenge” set by the Bill and Melinda Gates Foundation.
The foundation, established by Microsoft co-founder Bill Gates and his wife, sought designs for toilets that could be part of a recycling system for waste and that would cost no more than five cents per day and per person.
An estimated 2.6 billion people — more than a third of the world’s population — lack access to a decent toilet, a situation that adds to disease and unhealthy living conditions.
The Swiss design team was led by process engineer Tove Larsen, who explained that the award-winning model is a “modern squatting toilet”.
It allows for the separation of urine and has an ingenious seal against odours while using just 1 to 1.5 litres of water for each use.
“This is absolutely decisive for cleaning the toilet, hand washing and the anal hygiene with water practised by Muslims and Hindus,” Larsen said in a news release.
The toilet needs no connection to a water supply.
Every time a user operates a foot pedal, water flows into a small water reservoir and used water is pumped upwards behind the toilet.
The used water is cleansed by means of a membrane filter, with germs removed through electrolysis from a solar powered electrode.
The Swiss-Austrian team’s design was honoured at an award ceremony in Seattle on Tuesday with a $40,000 prize.
The next challenge is to build and test prototype toilets for use in the real world.
Larsen said the team has already developed a business model for use of the toilet as part of a “total sanitation system” that can be managed by local people.
The toilets are designed to be modular, with containers holding faeces capable of being transported hygienically to treatment plants.
The plants in turn can turn the waste into fertilizer and biogas under the model proposed.