‘Off-grid’ toilet to be tested in Durban, South Africa

18 million people in South Africa lack access to toilets or improved sanitation, and the country lacks water resources

Toilet processing system - waterless toilet
Toilet Processing System

RESEARCH TRIANGLE PARK, NC – A prototype “off-grid” toilet system developed by researchers at RTI International, in partnership with Duke University and Colorado State University, will soon begin a testing of the system in Durban, South Africa.

The project is funded through a grant from the Bill & Melinda Gates Foundation Reinvent the Toilet Challenge.

The innovative on-site waste treatment is designed as a closed loop system, with technology to treat and reuse the liquids and generate power for the system through the combustion process.  It is designed to operate off-grid – without piped-in water, a sewer connection, or outside electricity – converting human waste into a burnable fuel, stored energy, and disinfected, non-potable water.  The system is targeting an operating cost of less than $.05 (U.S.) per day.

The prototype waste processing system will be set up in an informal settlement community in Durban, South Africa. The unit will process waste from a community ablution block that includes shared toilet, shower and washing stations. The field testing program will be working in partnership with the eThekwini Municipal Water Services and with the University of KwaZulu Natal in Durban to test the system in a community of about 1,000 residents.

This multi-year field testing partnership will help the team to optimize system performance, gather user insights, and advance potential commercial partnerships. 

Sanitation in the city of Durban, South Africa, is available to approximately 83 percent of the population. However, one in three households live in informal settlements, and access to safe sanitation is much lower in these unplanned, poor communities. eThekwini Municipal Water Services is looking at how new innovative technologies can help close the sanitation gap.

Since late 2015, RTI has been field testing and further developing the technology in Ahmedabad, India. Prototype testing provided key insights from users on the technology and the design, along with feedback on the approach to on-site waste treatment. By testing the system in India, the team gained operational insights on use patterns, weather, and environmental conditions.

“Field testing in India has given us insights on operations and user practices and perceptions, and prepared us for new testing with different use cases,” said Brian Stoner, Ph.D., project director at RTI. “ It is exciting for us to start a new partnership in Durban.”

Use patterns and climate conditions will be different in Durban. RTI also adjusted the India prototype to meet cultural practices in South Africa that use seated toilets and toilet paper.

“Our mission is to support significant improvements in public health, the environment, and quality of life, and to do so we have to get closer to our clientele to better understand their needs and aspirations,” said Myles Elledge, RTI international partnership lead for the project.