If there were one country that symbolized the adage “Necessity is the Mother of Invention” it’d be Singapore. With their acute water shortage, Singapore needs to literally buy water from Malaysia for day to day purposes. Exemplifying ‘desperate times call for desperate measures’, Singapore’s national water agency implemented the idea of redirecting “used” water to dedicated treatment plants to obtain what they call “NEWater” ! They call it Toilet to Tap technology. Treating waste water to make it potable obviously needs a lot of electricity making this water quite expensive. And here comes an interesting twist to the tale…
Scientists from Singapore’s Nanyang Technological University (NTU) have developed a toilet system that can convert solid human waste (yes, poop) to fertilizer AND electricity. So in a way, the excess electricity needed for the water treatment could be obtained from the very thing that dirties the water! Also, this inventive toilet reduces the amount of water used in flushing by 90% compared to the current toilet systems in Singapore.
Electricity from toilets is catching up as a trend with The Bill and Melinda Gates Foundation investing $42 million to develop such toilets in the poorest regions of the world. One Gates funded project will build toilets that convert feces to charcoal, salt and clean water.
The Gross details:
Coming back to the unusual toilet developed by NTU, it is called “No-Mix Vacuum”as separates liquid and solid waste into two different chambers and employs the vacuum suction technology used in airplane lavatories. The vacuum technology results in the considerably less amount of water needed for flushing. The liquid waste is directed to a processing facility where fertilizer components like nitrogen phosphorous and potassium can be extracted from it. The solid waste is directed to a bioreactor which digests it to produce biogas.
The biogas generated by this bioreactor basically consists of methane which can easily replace natural gas used for cooking- which is the case in Indian villages that extensively use biogas generated from cattle manure. This methane can also be used in fuel cells to generate electricity- an example of such a system being the wastewater plant at Portland, Oregon . So that’s what the Singaporean scientists wish to do- poop to methane to electricity!
Turning vulnerability into a strategic advantage
The resource scare country aims to have a complete recovery of available resources without wasting any. This innovative toilet stands testimony to this fact as if it replaces a public restroom flushed 100 times a day, it can save 160000 liters of water each year. Recently Bradford too started work on its human waste to electricity converter power plant which is expected to be up and running by 2013 and would save the city up to a third of its £45m energy bill. But unlike such large scale plants, separating and processing the human waste at the source saves energy and makes it cost effective. The NTU scientists are now testing this system in two NTU restrooms and if all goes well, our next trip to the loo would truly “energizing”
This entire concept may seem repulsive but considering how electricity generation pollutes our world, it’d be great if some of the muck is put to good use. Electricity from human waste seems to be the latest green technology, and if this is our new generator of energy, one thing is for sure- it is an inexhaustible source…
Feature image: http://bit.ly/PCq2Al