Vacuum toilets use air to transport sewage, reducing water consumption. Within the Run4Life project, an ultra-low flush toilet was developed by JETS, reducing the water consumption to 0.5-0.7 litre per flush. In comparison, a modern gravity flush toilets uses 3-10 litres. More information on the ultra-low flush toilet can be found in this factsheet.
The lower flushing volume gives not only a notable water saving effect, but also results in highly concentrated sewage. The high concentration increases the efficiency of resource recovery technologies.
For more information on vacuum toilets please download the factsheet.