The Reinvented Toilet


Our unassuming toilet is due for a revamp.

Yes, this is a blog post about poop. Indeed, the toilet has left something to be imagined in the world of innovation. While some toilets have heated seats or even an attached bidet, it's fair to say toilet innovation has lagged behind that of vehicles, robotics, medical devices, appliance connectivity, you name it. The flush toilet was invented in 1596.

bill gates

bill gates

Toilets have been largely ignored for hundreds of years, despite the fact that the lack of proper sanitation systems is estimated to be responsible for the annual death of 1.5 million children (500,000 under the age of five), and over $200 billion in annual healthcare costs. Human waste is riddled with diseases and germs and, unfortunately, developing nations do not have the same sanitation luxuries as do developed nations.

In fact, only 27% of the entire world's population has a toilet in their home that sends waste to sewers and subsequently treatment plants (World Health Organization). 

The implications? Over 5.5 billion people are not privy to proper sanitation. The very poorest 2.5 billion people are without any toilet nor latrine whatsoever, forced to defecate in rivers, street gutters, and household yards, paying a tremendous daily price in health, safety, and dignity.

Bill Gates has been bullish on toilets for the better part of the last decade, striving to solve a massive global health crisis. If ever there was a true win-win, Gates believes the toilet industry will be worth $6 billion by 2030. The WHO has calculated improved sanitation equates to approximately $9 in social and economic value per every $1 investment, due to reduced healthcare cost, illness, disability, premature death, and increased productivity.Similar to many other innovations, simply exporting developed world toilets to the developing world is not an option. For starters, conventional toilets use too much water. In the U.S., toilets account for almost 30% of an average household's indoor water consumption (Environmental Protection Agency). Even if the toilets of today were more water efficient, the developing world does not have the infrastructure to support said toilets, tremendously lacking sewers and waste treatment systems.In 2011, the Bill and Melinda Gates Foundation launched the Reinvent the Toilet Challenge, asking innovators to redesign the toilet to be able to capture and process human waste without piped water, sewer or electrical connections, and to turn human waste into clean energy and clean water. Oh, and the toilet must be affordable. Talk about waste to wealth. Since Challenge launch, Bill and Melinda Gates have already funded over $200 million into toilet inventions and have committed an additional $200 million to help scale.

"All the participants are united by a common desire to create a better world - a world where no child dies needlessly from a lack of safe sanitation and where all people can live healthy, dignified lives." - Bill Gates

Gates often compares the toilet revolution to computing development in 1975 when he founded Microsoft. "In the way that a personal computer is sort of self-contained, not a gigantic thing, we can do this chemical processing at the household level," Gates explains.The toilet as we know it sends waste away with water through a sewer system, ending up at a treatment plant. All with a simple flush by its user.The toilet of the future is self-contained, odorless, kills germs, converts human waste to clean water, fertilizer, and electricity, and is not reliant on water.

At the 2018 Reinvented Toilet Expo in Beijing, Gates and technology partners revealed two major breakthroughs: 1.) The Omni-Processor: a small-scale treatment plant that takes in human waste and converts the waste into valuable products like electricity, fertilizer, and clean water, killing dangerous germs during conversion, and  2.) The Reinvented Toilet: a self-contained unit that has an extremely small treatment plant built in, working very similarly to the Omni-Processor and destroying germs in the process of converting waste to electricity, fertilizer, and clean water. Twenty different toilet designs were featured at the Expo. Technology partners also presented breakthroughs in odor management, urine/solid separation, and liquid treatment. Bill Gates described the products shown at the Expo as the most significant advances in sanitation in nearly 200 years.

The Nano Membrane Toilet, designed by Cranfield University and backed by Gates, is one of the leading inventions. After the user is finished and closes the lid, the seat's hinge turns a series of gears 270 degrees depositing the waste into the bottom of the bowl and squeegees it, with no water or power. This is the "flush", and it is completely odorless. The waste enters into a holding chamber below, where solid sinks and liquid floats. An Archimedes screw lifts the solid waste to the top into a holding chamber, where it is converted to ash and energy and covered in a scent-suppressing wax. Urine is separated, cleaned, purified, and deposited into a different holding chamber.

The nano-structured membrane wall enables the water (from the urine) to transport in vapor form, rather than its natural liquid state, which helps to kill pathogens and odorous compounds. The water is saved in a separate chamber and can be used for outdoor irrigation and cleaning. Every week, a local technician removes the solid waste and replaces the toilet's batteries if it needs it. One toilet can accommodate up to 10 people for less than 5 cents per day, per user, which was part of Bill and Melinda Gate's original challenge criteria.

Short video below explains in much greater detail. [youtube]

Other terrific designs were presented at the Expo. The California Institute of Technology won $100,000 for designing a solar-powered toilet that not only runs off renewable energy, but also produces hydrogen and electricity. Loughborough (United Kingdom) won $60,000 for a toilet that produces clean water, minerals, and biological charcoal.The critics (ahhh yes, there are always critics), question whether or not these toilets can be scaled and affordable for the people that need them the most. There are certainly still limitations. The Nano Membrane toilet, for example, requires scheduled maintenance, which will be hard to accommodate in very remote areas. The Nano Membrane toilet also requires toilet paper to be tossed into a nearby waste bin. But - it is a tremendous improvement for households with no toilet at all.

A waterless toilet, you say?

Perhaps, if you are one of the 27% with a toilet and effective sanitation system, you are wondering how these new toilet inventions impact you personally.Let us not forget water scarcity is one of the greatest risks our society has ever faced. If we take the sanitation revolution one step further, consider the following.

If enough effort is put towards the mission of water-less toilets and toilets that can turn urine to clean water, could we not only bridge a massive gap in the developing world, but also replace toilets in the developed world to decrease water use and turn waste into energy?

Kudos to Bill and Melinda Gates, and all of the companies inventing our future toilets, for working ferociously to solve a massive global issue.