Who would have expected a toilet to one day filter water, charge a cellphone or create charcoal to combat climate change? These are lofty ambitions beyond what most of the world’s 2.5 billion people with no access to modern sanitation would expect. Yet, scientists and toilet innovators around the world say these are exactly the sort of goals needed to improve global public health amid challenges such as poverty, water scarcity and urban growth.
Scientists who accepted the Bill & Melinda Gates Foundation’s challenge to reinvent the toilet showcased their inventions in the Indian capital on Saturday. The primary goals: Sanitize waste, use minimal water or electricity and produce a usable product at a low cost.
The World Bank estimates the annual global cost of poor sanitation at US$260 billion, including loss of life, missed work, medical bills and other related factors. India alone accounts for US$54 billion — more than the entire GDP of Kenya or Costa Rica.
India is by far the worst culprit, with more than 640 million people defecating in the open and producing a stunning 65,317.3 tonnes of human waste each day — the equivalent weight of almost 10 Eiffel Towers or 1,800 humpback whales.
Pooping in public is so acceptable that many Indians will do it on sidewalks or in open fields. Gaze out the window of any Indian train and face a line of bare bottoms doing their business on the tracks.
Meanwhile, diarrheal diseases kill 700,000 children every year, most of which could have been prevented with better sanitation.
“In the West, such things are a nuisance, but people don’t lose their lives,” Christopher Elias, president of global development at the Gates Foundation said. “People don’t immediately realize the damage done by infections coming from human waste.”
India has been encouraging rural communities to build toilets and last year launched a US$1.6 billion program to help. However, building sanitation systems in developing countries is not easy. Flush toilets are not always an option. Many poor communities live in water-stressed areas. Others lack links to sewage pipes or treatment plants.
To be successful, the designs being exhibited at Saturday’s Toilet Fair had to go beyond treating urine and feces as undesirable waste to recognize them as profit-generating resources for electricity, fertilizer or fuel, scientists said.
The designs are mostly funded by Gates Foundation grants and in various stages of development, though others not created as part of the Gates challenge were also exhibiting on Saturday.
Some toilets collapsed neatly for easy portability into music festivals, disaster zones or illegal slums. One emptied into pits populated by waste-munching cockroaches and worms.
One Washington-based company, Janicki Industries, designed a power plant that could feed off the waste from a small city to produce 150 kilowatts of electricity, enough to power thousands of homes.
The University of the West of England, Bristol, showcased a urine-powered fuel cell to charge cellphones overnight.
Another team from the University of Colorado, Boulder, brought a system concentrating solar power through fiber optic cables to heat waste to about 300°C. Aside from killing pathogens, the process creates a charcoal-like product called biochar that is useful as cooking fuel or fertilizer.