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.
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.