A biogas digester sounds like a complicated piece of scientific equipment, doesn’t it? After all, if it takes care of your leftover food while creating renewable energy for your home at the same time, it has to be rather complex, right?
As you can see, the one built by Thomas H. Culhane isn’t. It’s just a small bucket sitting inside a larger one and a few plastic tubes.
And it’s precisely this simplicity that makes it so beautiful.
In the video below, Culhane (an urban planning professor and a member of the National Geographic Emerging Explorer program) demonstrates that with just a few supplies from a hardware store, you can construct your own biogas generator.
“Once you understand the principle you can build a home system that uses all your kitchen garbage and gives you up to 2 hours of gas every day,” he says.
Here’s how it works: When the biodigester is fed organic waste, the bacteria inside the larger bucket eats it up and converts it into methane gas through a process called anaerobic digestion. The gas that’s created can then be used to generate heat for cooking, water, or electricity, while the digested leftover waste can be used as a high-quality fertilizer.
Culhane has taken his invention around the world, from the slums of Cairo and the favellas in Brazil. As the Christian Science Monitor reports, he founded Solar CITIES Solutions, an NGO (non-governmental organization) that provides materials and training for individuals in impoverished communities to create sources of clean, renewable energy in their homes.
While Culhane’s approach is meant for the average home, biogas is being championed for large-scale as an alternative to fossil fuels. The Natural Resources Defense Council says that the use of animal manure biogas is the “ultimate win-win energy source,” as it allows farmers to make their own energy, reduce water contamination, odor pollution, and global warming emissions caused by animal waste.
Turning waste into a resource. Now that’s an idea that shouldn’t go to, ahem, waste.