(CNN) -- In the crowded slums of Lagos, Nigeria, untreated sewage mingles with the chaotic network of pipes that deliver water to the city. Those who can't afford a local borehole or a private vendor know better than to take their chances with the taps -- most preferring to go thirsty instead. That's according to Olatunbosun Obayomi, a Lagosian microbiologist and inventor who has lived in the city all his life. But now Obayomi thinks he's found a solution -- one that not only tackles the slums' sanitation issues, but creates free, clean energy in the process. "With a cheap retrofit, household septic tanks -- the source of the sewage -- can be converted into biogas generators," said Obayomi, 29, whose concept has earned him a TED fellowship, a Nigerian Youth Leadership Award and growing international acclaim.
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Microbiologist says he has simple solution to sanitation problems in Lagos
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Conversion of septic tanks to biogas generators treats sewage and generates power
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Despite recognition, inventor says there are still cultural and political barriers to development
But, although @placeholder's retrofitted biogas generator is relatively cheap to build -- requiring only low-tech materials such as plastic pipes, cement and sand -- and despite all the recognition it's attracted, only a prototype has been installed so far.