The Coolest Ideas Coming From the Gates Toilet Challenge

The Reinvent the Toilet Challenge has been around now since 2011, making grants for big ideas to solve water and sanitation problems in the developing world. The latest round of winning research teams was announced over the weekend in India. Here’s what the contest has yielded so far. (Note: There will be no bathroom humor or puns in this post. You’re welcome.) 

The Bill and Melinda Gates Foundation is serious about taking on the problems caused by lack of safe and affordable sanitation worldwide. Some 2.5 billion people don’t have such access, and poor sanitation leads to 1.5 million child deaths every year. Gates came up with a competition that would support teams of researchers with bold ideas to improve access to proper toilets. It’s among the most prominent of the Gates “Grand Challenge” contests, which task research teams to solve problems such as building a better condom.  

The goal of this particular challenge is to create a toilet that is cheap, sustainable, sanitary, works off the grid, and recovers valuable resources from waste. Easy-peasy. The latest round of the competition ended recently, with a focus on India. Six teams of researchers were awarded grants totaling $2 million, joining 16 other teams from earlier rounds. Here are some highlights from the India contest:

  • A project to develop a household container of Black Soldier Fly Larvae that can be used to convert human waste into usable product for agriculture. By the Indian Institute of Technology Roorkee in collaboration with Fresh rooms Life Sciences 
  • A solar-powered toilet that features a standalone, off-the-grid waste processing system. By Eram Scientific Solutions Pvt. Ltd., Kerela in collaboration with University of South Florida. This is the second toilet challenge grant Eram has received for its “eToilet” system. The company website cites more than 400 eToilets currently in use. 

Previous winners include:

  • A handful of solar-powered concepts, including one toilet conceived at University of Colorado Boulder that disinfects liquid and solid waste and produces biochar, which can be used as fuel or fertilizer. 
  • Biochar is a popular byproduct of toilet designs, with one particular project from Loughborough University in the UK that transforms waste into the fuel, while recovering water from the feces and urine it processes. The system is powered by heat from combustion of the biochar it creates, which is kind of amazing.
  • Delft University of Technology in the Netherlands won a grant to develop a toilet that would use microwaves to gasify the waste, which can be fed into a fuel cell to generate electricity.

Gates' Silicon Valley-like approach to the problem has met some criticism. One environmental engineer who works in developing countries cited the unlikely chance that such bright ideas could be practical at low cost, and the much higher potential of spreading existing, low-tech sanitation solutions. 

Indeed, many of the winners sound a bit fancy to serve the billions of people in need. But not all of the solutions are necessarily that high-tech. For example, one winner proposes a handheld pump and membrane system. Another uses an air blower and a sand-like material. 

While science research isn’t explicitly the concern of the Gates Foundation, the country’s largest funder has taken to inviting research teams to solve the trickier problems associated with global poverty and health. The toilet challenge is a prime example, and one of the more high-profile, but the Grand Challenges in Global Health program has hosted research competitions on issues ranging from measuring infant brain development to intestinal disruption. Read about the latest round of challenges here.