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An Uber to transport poo

TANYA THOMAS | Updated on January 23, 2018

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You’ve got to be kidding!

No, it’s really happening.

Where?

In Senegal, Africa.

And what is Senegal doing with its poo?

It’s a new method of waste management that Dakar, the capital of the west African nation, is experimenting with. Eighty per cent of Senegalese use pit latrines (much like a hole in the ground). Also, pit-emptiers, as they are called, charge exorbitant amounts to clean up used pits. The Senegal National Sanitation Utility thinks it can finally solve the problem with its new SMS service that lets people send a text message to the government when it’s time to empty their pits.

So what’s the connection to Uber?

The government utility then issues a tender to all the pit-emptiers in the neighbourhood (the way Uber informs drivers using its service about a passenger needing a ride).This prompts a bidding war to get the faeces collected and delivered to a central location, significantly reducing the waste management costs that people had to earlier bear in their individual capacities. The SMS service, financed by the Bill and Melinda Gates Foundation, already has about 65,000 users and aims to be not just sustainable, but even profitable.

Wow! And how much have costs come down?

In the first year of the service, a spokesperson for the government agency told The Guardian, the average cost of emptying pit latrines decreased from $150 to $90 a year per user. The target is to bring it down to the $60 range. But according to official estimates, Dakar produces 1,500 sq m of faecal sludge a day of which only 1,100 sq m are collected and processed. If the experiment needs to be successful, it should be available to every Dakar resident.

What happens to the collected poo?

Imagine being able to sell your poo for money! The Gates Foundation has also funded the building of an omniprocessor, which can convert the faecal matter into a saleable commodity, like electricity or ash. Not to mention that the steam produced when drying the sludge can be filtered, condensed and treated, to produce potable water. According to news reports, the omniprocessor can produce net power of 250KW of electricity and 80,000 litres of drinking water a day.

There’s gold in poo, clearly!

Figuratively and literally. In a study funded by the US Geological Survey Mineral Resources Program, scientists have found treated solid waste contains precious metals such as gold and silver. Industrial metals which can be used in electronics and alloys, like palladium and vanadium, can be mined from toilet waste.

For real?

We kid you not. Samples takes from close to a hundred wastewater treatment plants in the US were tested to show that they were rich in silver, gold and platinum-group metals. According to the study, about 1kg of sludge could typically contain about 0.4mg gold, 28mg silver, 638mg copper and 49mg vanadium. A Tokyo plant has already started extracting gold from sludge and says the process beats mining hands down while Sweden is experimenting with making bioplastics from human waste.

So the Senegalese are not bonkers.

They might soon be turning a profit from the system as well. In fact, the model — if it succeeds — can be adopted by other congested regions where people are not connected to a sewage system. Maybe, Africa shall lead the way.

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Published on August 12, 2015

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