Compost as Bio-Fuel

Those of you who have been following my posts on Renewable Energy will have seen that I focus primarily on Solar and Wind power generation projects. I have a passing interest in hydro-generation, but it is merely a curiosity for me. Today, my web-trolling took me in a new direction !

The French Innovator, Jean Pain, pioneered a new form of bio-fuel, which he used to provide all the energy he required to run his modest farm. At the heart of his system was compost !
Composting is the biological process by which organic matter is broken down. It can then be used as a rich soil additive and natural fertilizer.

Pain was not a scientist - rather, he was a keen observer. He realized that if he reached into the center of his compost heap, the temperatures were high enough to burn his skin. Further, he found that a bi-product of the composting process was methane gas. He then used a little gonzo engineering and devised a process to capture both the heat and the methane, so that he could harness their energy on his little farm.

It should be noted that his yield was not insignificant. He could produce some 500 cubic meters of methane gas in just 90 days. Enough to power two gas ovens and a three-burner stove for a year. He also made a simple carburetor modification to his truck so that it too could be methane-powered. Lastly, he had a methane-powered generator to produce electricity for his farm. For clarity's sake, methane is more commonly referred to as Natural Gas.

His was an interesting contraption: the heart was a hermetically-sealed tank, filled three-quarters full with organic matter (macerated tree limbs and brush) which had been steeped in water for 60 days. As the contents decomposed, creating methane which he siphoned off, the heat byproduct was captured by a 200 food coil of tubing - a crude heat-exchanger. The whole works was buried in a 50 ton compost heap, which in turn generated it's own heat. The main "plant" (sorry, but I really couldn't resist !), was some six meters wide and three meters tall.

The compost heap itself was a mix of all sorts of organic matter, including finely chopped tree limbs, brush, clippings and the wastes from their kitchen - all of which was freely available on his farm. He built his contraption using tools and equipment commonly found on his farm, including some 24 truck inner-tubes, which served as the bladder he collected the methane gas in.

Pain was a scientist and an engineer. He was also a conservationist. He is the modern inspiration of the so-called green movement.

*** Author's Note :: Astute readers will note that I have highlighted the term "organic matter" a number of times. The proper definition is that of matter which is capable of decay. In the last year or so, Marketing-types have tried to create a definition to mean "free of pesticides and fertilizers". I personally despise that term & challenge any and all marketing types to show me a NON-organic carrot ! ***

The opinions expressed are purely those of the author. Opinions are like noses - everyone has one, and they are entitled to it !