NEW DELHI – 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 Saturday. The primary goal: to sanitize waste, use minimal water or electricity and produce a usable product at low cost.
The World Bank estimates the annual global cost of poor sanitation at $260 billion, including loss of life, missed work, medical bills and other related factors.
India alone accounts for $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 72,000 tons of human waste each day – the equivalent weight of almost 10 Eiffel Towers or 1,800 humpback whales.
Meanwhile, diarrheal diseases kill 700,000 children every year, most of which could have been prevented with better sanitation.
But 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, scientists said, the designs being exhibited at Saturday’s Toilet Fair had to go beyond treating urine and feces as undesirable waste and recognize them as profit-generating resources for electricity, fertilizer or fuel.
One Washington company, Janicki Industries, designed a power plant that could feed off the waste from a small city to produce 150 megawatts 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 degrees Celsius.
Aside from killing pathogens, the process creates a charcoal-like product called biochar useful as cooking fuel or fertilizer.