- About 2.5 billion people around the world do not have access to modern sanitation.
- Bill and Melinda Gates Foundation challenged the scientists to reinvent toilet.
- The main goals of this challenge are:
- Sanitize waste,
- Minimal use of electricity and/or water,
- Produce a usable / re-usable product which is cheap.
- Designs by various scientists were showcased at “Toilet Fair”.
- Some of the interesting designs were:
- Urine powered fuel cell to charge cell phones.
- 150 megawatts of electricity could be produced, which in turn could provide energy to 1000s of houses.
- Another design, used fibre optic cables, built solar power concentrating system. Heat up to 300 degrees Celsius could be generated which could be used to kill pathogens and generate biochar which can either be used as fuel for cooking or as fertilizer.
- Gates Foundation funded all the projects in various stages.
Exams Perspective:’
- Sanitation
- Hygiene
- Biochar