Reinvent the Toilet, sponsored by the Gates Foundation, asked designers and engineers to develop self-contained toilets. They do not need sewers yet dispose of waste cleanly and efficiently. This is crucial in areas where sanitation can be a problem. Many of these new toilets turn poop and urine into fertilizer and water for more flushing and washing hands.
There are also major social benefits, especially for women.
Melinda Gates explains:
They’ll also improve lives—especially for women and girls. Life without a toilet is hard for anyone, but it tends to be women and girls who suffer most.
Bill and I have both met women who have suffered kidney damage from holding in urine all night to avoid a risky trip to dangerous public facilities. We’ve met others whose only place to defecate is in an open field, so they restrict their food intake all day and wait for cover of darkness to relieve themselves in relative privacy. There’s also some qualitative evidence that suggests that girls are more likely to miss school during their periods when their school doesn’t have a decent toilet. (When you learn just how entrenched stigma around periods still is in many places, you can start to understand why someone would rather fall behind on her studies or miss wages than risk humiliation.)
Bill Gates discusses the Reinvent The Toilet Expo:
The toilets at the expo aren’t just fascinating gadgets—they have the potential to save millions of lives. More than half of the world’s population uses unsafe sanitation facilities. Even in places where people have access to toilets or pit latrines, their waste isn’t disposed of safely. The pathogens from the waste find their way into the local water supply and makes people sick.