Doomsayers may argue that issues such as overpopulation, climate change and ever-scarcer food and water are guaranteeing the Four Horsemen of the Apocalypse an easy ride. But science may offer solutions to some of the biggest threats facing our planet. Organised by Intelligence Squared and Deutsche Bank, the Tomorrow’s Horizons event showcased work from four innovators intent on building a better future. Former BBC Environment Correspondent Alex Kirby reports.
Poop into power
It sounds too good to be true, like the medieval philosopher’s stone that reputedly turned base metals into gold. But Muhammad Sohail, Professor of Sustainable Infrastructure at Loughborough University, is developing a toilet that will radically improve the health and dignity of millions of people by turning human waste into charcoal, salt and clean water – and run itself.
Nearly 40% of the world’s people – 2.6bn of us – have no access to basic sanitation. That means some desperate remedies, like East Africa’s “flying toilets”: you defecate into a plastic bag, then hurl it as far away as you can. The consequence is suffering on a massive scale: the World Health Organisation says 115 people in Africa die every hour from diseases linked to poor sanitation, poor hygiene and contaminated water.
What if safe and affordable toilets were available worldwide? That’s what Professor Sohail’s Turning Poop into Power project aims
to provide – with some valuable by-products along the way. Loughborough University won $60,000 in an international competition organised by the Bill and Melinda Gates Foundation to reinvent the toilet, making it clean, safe and available to all – and with no need for a connection to electricity or a sewer.
Loughborough is developing a prototype to prove its concept and hopes to have a working version soon. Using a process called continuous thermal hydrocarbonisation, the university’s multi-disciplinary team has produced a toilet that can convert human waste into
charcoal for soil conditioning or for use as fuel, water for flushing and hand-washing and several other by-products – including chlorine for sterilising the installation and urea and phosphates for agricultural use.
The secret lies in what comes out of us and goes into the toilet. “There’s a link between what we eat and what we excrete,” says Professor Sohail. “There’s still some calorific value in excreta. So as long as you have a critical mass of it – or a critical quality – the system will work. It’s really a sort of continuous pressure cooker.”
This ‘cooker’ operates at 200ºC and 20 times atmospheric pressure, conditions that kill all known germs. The prototype is designed for use by anything from 30 to 100 users, but the team’s aim is to produce a household version.
For that, achieving the critical mass required could be one of the puzzles still to be solved: it
2.6bn
of the world’s population have no safe sanitation facilities
1 in 7 80%
Source: Bill and Melinda Gates Foundation
people worldwide don’t use a toilet
of human waste currently goes straight into rivers and streams