Tag Archives: California Institute of Technology

Hi-tech toilets save lives – and mean big business

Hi-tech toilets save lives – and mean big business | Source: Matthew Wall, BBC Business News | Oct 8, 2012

In a world where 2.5 billion people still do not have access to basic sanitation facilities, and 1.5 million children die each year from preventable diseases as a result, there is a pressing need to find sustainable solutions to this most ancient of human problems.

But this isn’t just a humanitarian issue – it is also about hard-headed economics.

“The United Nations estimates that achieving the Millennium Development Goal for sanitation could save us $66bn [£41bn] in time, productivity, averted illness and death,” says Sanjay Bhatnagar, chief executive of WaterHealth International, a provider of water purification centres to developing economies.

“Every dollar spent on improving sanitation generates nine times the amount in economic benefit.”

In short, an ill workforce is an unproductive workforce. Improve health, improve productivity.

Flushed away
Flushing loos in one form or another have actually been around since the third millennium BC, as archaeological evidence from the Indus Valley Civilisation reveals.

But modern flush toilets, which use 10 times the average daily drinking water requirement, are hopelessly unsuited to countries with poor access to water or sewerage networks.

So the world’s finest scientists and inventors have been applying their technological know-how to the unglamorous but important issue, and coming up with some ingenious solutions.

In 2011, the Bill & Melinda Gates Foundation launched the Reinvent the Toilet Challenge, awarding $3.2m in grants to promising entrants.

The conditions were tough. Designs had to be hygienic, sustainable, cheap to operate, and capable of working “off-grid” – without connections to water, electricity, or sewerage networks.

Ideally, they should also be capable of reclaiming reusable materials from human waste.

In August this year, Bill Gates awarded the $100,000 first prize to Dr Michael Hoffmann, professor of environment science and engineering at the California Institute of Technology, for his team’s solar-powered loo.

Caltech PhD student Clement Cid with the new solar-powered sanitation system

It uses an electrochemical reactor to break down human waste into fertiliser and hydrogen gas, which can then be stored in electric fuel cells. The treated water can be reused to flush the loo or irrigate crops.

A panel of photovoltaic cells captures light and converts it into electricity stored in rechargeable batteries. One day’s light can produce enough power to run the entire electrochemical sanitation system night and day.

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Caltech’s prize-winning solar-powered toilet – video

A video demonstrates the working of the prototype of the solar-powered toilet that won the first prize of US$ 100,000 in the Reinventing the Toilet Challenge issued by the Bill and Melinda Gates Foundation. The Solar-Powered Self-contained Human Waste Water Treatment System was developed by Prof. Michael Hoffmann‘s research group at the California Institute of Technology (Caltech).

In 2011 the Caltech team was awarded a US$ 400,000 grant to create a toilet that can safely dispose of human waste and reuse water for just five US dollar cents per user per day.

Solar energy powers an electrochemical reactor, which converts human waste into fertiliser and hydrogen, which is stored in hydrogen fuel cells as energy. The treated water can be reused to flush the toilet or for irrigation.

The toilet, which could cost US$ 1,000 or more per unit according to the Seattle Times, is still a prototype and would need to be adapted before it can be launched commercially.

Source: Marcus Woo, Caltech, 15 Aug 2012 ; Theodoric Meyer, Seattle Times, 14 Aug 2012

Winners of the Reinvent the Toilet Challenge

August 14, 2012 | By Bill Gates

Today I attended the Reinvent the Toilet Fair— a fascinating learning experience and an important step in providing safe sanitation for everyone in the world.

A solar-powered toilet that generates hydrogen and electricity – California Institute of Technology

A year ago, the foundation launched an initiative to tackle the problem of sanitation in the developing world. We called it the Reinvent the Toilet Challenge. In this photo gallery you can learn more about each of the grantees and their sanitation solutions.

This week in Seattle, the foundation is holding a Reinvent the Toilet Fair. Today I awarded prizes to three universities who responded to our challenge a year ago to come up with solutions for capturing and processing human waste and transforming it into useful resources.

The winners included:

  • first place to California Institute of Technology in the United States for designing a solar-powered toilet that generates hydrogen and electricity,
  • second place to Loughborough University in the United Kingdom for a toilet that produces biological charcoal, minerals, and clean water, and
  • third place to University of Toronto in Canada for a toilet that sanitizes feces and urine and recovers resources and clean water.

A special recognition was awarded to Eawag (Swiss Federal Institute of Aquatic Science and Technology) and EOOS for their outstanding design of a toilet user-interface.

Watch this AP video report on the Reinvent the Toilet Fair.