Bill Gates isn’t afraid of potty talk.
On Tuesday, he got onstage in front of business leaders, investors, and government officials from around the world and unveiled what he politely referred to as a “little exhibit.” It was a glass jar filled with human feces.
“It’s good to be reminded, in there could be over 200 trillion rotavirus particles, 20 billion Shigella bacteria, and 100,000 parasitic worm eggs,” Gates told the crowd, which had gathered in Beijing, China, for an event called the Reinvented Toilet Expo.
The jar of poo was used to make a point: Around the world, in places without proper sanitation or sewage systems, there’s much more than a jar’s worth of unsanitary human waste sitting around.
“That’s what kids, when they’re out playing, they are being exposed to all the time,” Gates said, noting the link between bad sanitation and disease, death, and malnutrition.
To address that problem, the Bill and Melinda Gates Foundation started its Reinvent the Toilet Challenge in 2011. The initiative funded $200 million in grants for universities around the world to develop a next-generation toilet. The goal: develop a waste-processing system that doesn’t need to be hooked up to a typical sanitation and sewer grid.
The new systems that have been created with those grants turn what we put into the toilet into fertilizer, energy, or recycled water — some of which is good enough to drink.
The Gates Foundation now intends to invest an additional $200 million into research that can yield additional ways to deal with human waste at the source.
Living without a good toilet can be unsafe. People who come in contact with fecal matter face a risk of deadly infections and chronic health problems, since human feces carry pathogens like E. coli, Streptococcus, hepatitis A and E, and more. Those can cause pneumonia and diarrhea — the top two killers of kids around the world.
Plus, if people don’t have a place to go at home, they have to travel alone into woods or a field to relieve themselves, which can be risky for women and children living in conflict zones.
“When you think about things that are basic, right up there with health and enough to eat, I think having a reasonable toilet certainly belongs on that list,” Gates said.
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He estimates that illness from poor sanitation costs the world over $223 billion per year in lost wages and extra healthcare.
With stratospheric rates of population growth in cities across Africa and Asia, the problem is only set to get worse.
“Unless we do something, the cycle of disease will actually be accelerated,” Gates said.
Gates doesn’t think it’s practical to expect the entire world to connect their homes to yet-to-be-built sewer systems and wastewater-treatment plants. That’s why he has been on a quest to do for toilets what he argues Microsoft did for computing: get the business off a centralized, “mainframe” system.
Gates started by asking engineers at universities around the world a simple but unanswered question: “Could you leapfrog the long-accepted ‘gold standard’ of sanitation?”
“A decade ago, I didn’t think I would be able to tell you so much about poop,” Gates said.
One of the first new toilets is the solar-powered Eco-san system, pictured below. Based on technology developed at Cal Tech, the Eco-san extracts clean water from human waste and reuses it for future flushing.
Other models are also in the works from companies and universities around the world.
The University of South Florida’s NEWgenerator treatment system also runs on solar energy and can be hooked up to any existing toilet. It uses a nano-membrane filter (kind of like a coffee filter) with feces-digesting anaerobic bacteria inside to filter clean water out of the waste.
Another toilet from Cranfield University in the UK comes equipped with a little trap-door odor barrier and scraper so that it requires no water for flushing. Clean water is filtered out of waste via a large, orange screw in the tank, and solid waste is burned inside the toilet’s combustor, which converts the waste into ash and energy. (Thankfully, this all happens out of sight of the people who are using the toilet.)