Without safe sanitation facilities many families are forced to wash in and collect their drinking water from polluted waterways, which can lead to epidemics such as diarrheal disease
will still need enough waste to work properly. Professor Sohail acknowledges that the prototype needs refining: “We haven’t resolved all the issues yet,” he says, “but we think we’re on the road to some game-changing technology.”
The cost he’s aiming at is about $60 a month for a family, compared with the £20,000 he says is needed to plumb in a toilet in an industrialised northern country.
He believes the new toilet will be just as attractive there as in the developing world. And he is clear it must be culturally acceptable everywhere: “The world can be divided into people who sit and people who squat, people who wash and people who wipe. This is for them all.”
One of the neatest parts of the concept is that the toilet is entirely self-sustaining, again thanks to the basic material it’s processing. That’s why it has no need of an external source of power or water.
Producing its own water means it is self-cleaning, and the faecal material, provided the temperature and pressure are right, produces energy to make the electricity needed to power the installation.
With a grin, Professor Sohail apologises to his momentarily horrified audience for “forgetting to bring some samples – the finished product smells like coffee”.
He believes his team is close to success in the final stage of the Gates Foundation competition and in his personal quest to make toilets “a desirable space”.
Perhaps the new version is not quite the philosopher’s stone. But it does sound like something close to perpetual motion.
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On present trends global electricity demand will rise by 50% by 2050, the date when fossil fuel use should have fallen by half if we are to limit the impacts of climate change to something tolerable. If we rely on nuclear power to escape the fix, says Professor Düren, it would mean “building a new one-gigawatt reactor every day for the next 40 years”.
As he points out, however: “The sun is a nuclear reactor. It’s down tonight for maintenance, but tomorrow morning it will start up again.” The sun’s dependability and constancy, he says, can be replicated by our ingenuity. Not only will a tiny area of desert produce prodigious amounts of solar energy every day, it will also do it in the dark.
Solar farming in Africa
We’re not really short of energy. The solar power baking the world’s deserts provides more energy in six hours than humans use in a year. Professor Michael Düren, of Giessen University, is co-founder of a German-led plan, DESERTEC, to provide 15% of Europe’s electricity by 2050 from the Middle East and North Africa.
20 | Informed — Winter 2012
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