Waste not, want not as radical sewerless toilet is tested
● The sun and smart technology are set to change toilets into veritable “poo powerhouses” geared at saving water and providing sustainable sanitation for the poor.
A self-contained toilet system that uses a solar-powered electrochemical reactor to break down human waste into clean water and harmless fertiliser is being piloted in Durban.
And what looks like a humble porcelain throne from the outside has the potential to address the problems of pollution, water wastage and access to toilets.
The University of KwaZulu-Natal’s Professor Chris Buckley said the technical workings of the reactor go unseen beyond the bowl.
“From the outside it looks like a normal toilet; you wouldn’t know about all the technology,” he said.
Human waste goes into the electrochemical reactor, which, through electrolysis, strips away harmful elements.
The no-sewer toilets — if introduced en masse — don’t require drains, pipes, continuous electricity or treatment plants.
A failing sewerage infrastructure, beset by age and lack of maintenance, has been the bane of sanitation services in SA in recent years.
“There needs to be a mind switch in the way in which sanitation services are designed and implemented, which takes into account the reality of water shortages and the need to be part of the circular economy in which resources are recovered and reused,” said Buckley.
The system was developed by US-based company Caltech and was funded by grants from the Bill and Melinda Gates Foundation.
The toilets are being tested at a school the foundation would not name as yet.
The R600m programme to “reinvent the toilet” was launched by the foundation in 2011 and has seen a number of prototypes developed and now tested in SA.
“This particular project is not the solution but rather an important step in providing universal sanitation services,” said Buckley.
Jay Bhagwan of the Water Research Commission said radical solutions for water stress were pivotal.
“In the next few decades we will reach a point where … consumption is going to outstrip what we have.”
He said that though traditional and conventional interventions such as new dams and water re-use were necessary, “now is the time to be radical”.
“We use nearly 50% of treated fresh water to move human waste around our settlements. That is moving 200g of faeces for kilometres of sewerage networks through our settlements where sewage is installed,” said Bhagwan.
“This is where a great opportunity exists, specifically for new solutions which use low or no water and are completely off the sewerage grid.”
This would, he said, put nearly half of used fresh water back into the system and eliminate downstream problems associated with conventional waste management.