Biogas

photography by Myriam Abdelaziz

Can't help but wonder what could be produced by our landfill? It is interesting to observe that the old city landfill north of town, long capped and seeded, also the landfill adjacent to the Community Forest have not regenerated any vegetation other than sparse grass.


For many years our waste and wastefulness has not been a prime topic of discussion. Out of sight, out of mind was the order of the day. The desperate situation of some in other parts of the world, however, brings into focus what can become another valuable resource.


Our dependence on big systems--big oil, big coal--steers us away from little ones, such as biofuel made from garbage, that are transforming communities in other countries.


So begins an article By Hillary Rosner titled 'The Low-Hanging Fruit' published in the July 2011 Issue of Popular Science.  The full article can be found online by searching under that title.  It continues  ....

Like wildfire in a part of the world largely dependent on firewood and charcoal, a child at the school lights methane directly from the tank. Culhane says these moments are what best communicate the promise of biogas.


The Mukuru slum has little infrastructure: no sewage system, no underground gas lines, no landfills. Residents toss potato peels and plastic bags into the street. Eyes sting from charcoal smoke. But this jumble provides an opportunity to rethink some basic things, and to improvise new forms of energy.


Here, a few biogas systems like Culhane's are turning waste, the world's most pervasive and overlooked energy source, into fuel. In the process, they're also turning households into closed-loop systems of local energy production and reuse.


When microbes digest organic waste-sewage, manure, food scraps- in the absence of air, they produce methane (along with small amounts of carbon dioxide and water), which can run everything from electric lights to city buses. No one has figured out what kind of biogas system it would take to power a whole city. But in Kenya, a plastic tank and some tubing can transform a single household's entire energy cycle.


Culhane runs a nonprofit called Solar C3ITIES (Connecting Community Catalysts Integrating Technologies for Industrial Ecology Systems). It has no paid employees and is funded, barely, by individual contributions. He has built low-tech, low-cost biogas systems in Cairo, Lagos and the West Bank, and trained local people to maintain and replicate them.


To learn more about Thomas Taha Rassam Culhane and his work:
http://solarcities.blogspot.com/