Reinvented Toilet Technology in Development
Foss Toilet
Water-Recycling Reinvented Toilet
The Foss Toilet is a flushing toilet that recycles the flushwater and doesn’t require any connection to water or sewer and is completely off-pipe. With a normal flush toilet user experience, it’s designed to be easily installed and require only connection to household electricity and a bathroom air vent. The innovation of the Foss Toilet combines biological processing with a distillation process, so that the treated and recycled flushwater is always clean and clear.
- Normal flushing toilet experience
- Zero-liquid discharge, with no connection to water or sewer required, flush and fill the system on installation only
- Removal of completely sanitary solids once or twice per year
- Installs with only connection to household electricity and a bathroom air vent
Status of Development
- TRL 6 – early commercial prototype
Use Cases
- Household: Designed as a bathroom unit for 2 person all-day usage
Product is Appropriate For:
| 2-4 | $0.50 | 10 |
|---|---|---|
| Capacity(users/day) | Est. Cost $/user/day) | Life Expectancy (Years) |
How Does it Work?
Frontend
A low-flush macerating toilet
Processing
Solids and liquids are processed together in a single flow. A heated and aerated tank is used to biologically digest organic material while a humidification-dehumidification process produces a clear effluent for flushwater reuse.
Remaining undigested solids are dried for removal by the user once or twice a year. This solid is totally sanitary and has a light, inoffensive smell.
Inputs
-
Does the system require an external source of electricity?
Yes -
Does the system require the use of water?
No. only during the installation -
Does the system require any other "consumable" inputs?
No
Outputs
- How much energy will be recovered?
The heat of the degraded organic material is utilized internally to maintain the temperature of the bioprocess. - How much water will be recovered?
The system is designed to provide 100% of the flushwater required to continually use the system. - How much fertilizer or other byproducts will be produced?
None
Treatment
- Solids treatment
Drying - Liquids treatment
Aerobic, thermophilic digestion -
Are chemical processes used?
No - Are mechanical processes being used?
No - Are biological processes being used?
Yes - Does the system require any off-site or additional processing?
No
Business Considerations
- Estimated daily operating cost: $30 per month for 2 people
- Estimated capex: $10,000
- Size: Designed to fit within the typical space of the tank behind a flush pedestal toilet, about 36” wide x 60” tall x 14” deep.
- Maintenance Requirements: Dry solids need to be removed once or twice a year, about 10 pounds. This sanitary solid can be safely disposed in the garbage or compost.
- Life expectancy: 10 years
