In the last 200 years, humans have sent rockets to Jupiter, the Internet has transformed communication, the Human Genome Project has mapped the chromosomes. Yet in that time, toilets have remained the same.
Social taboos about defecation have stymied toilet technology from evolving beyond the ceramic water closet that allowed loos to be located inside homes. Aside from some automation and digital spray control, toilet technology has remained unchanged for two centuries.
Finally in 2011, the Bill and Melinda Gates Foundation launched the Reinvent the Toilet Challenge to provide safe and affordable sanitation solutions to 2.5 billion people worldwide who don’t have access to toilets. The idea was to stop open defecation with a cheap alternative that would also prevent the spread of infections.
The Foundation’s specification was to re-invent the toilet that would destroy the pathogens in human waste, convert it into energy, and not need to be connected to the sewage, water, or electricity grids. And, oh yes, it should also cost less than $0.5 cents per user per day and be suitable for urban poor and rural settings.
Many companies have joined the competition with ideas like: a solar-powered toilet that generates hydrogen and electricity, sanitation systems that convert human waste into biological charcoal, fuel gas, minerals and clean water. The challenge has gained momentum in India and China where engineers are coming up with innovative new technologies.