I have heard pros and cons with regards to this issue in the past. Basically, that it is not cost effective (right now) to utilize the small amount of methane produced from a septic tank. However, in the quest to become as self reliant as possible, does anyone know how to accumulate the "waste" gas produced or where I could find more info on this particular subject. It seems to me that if enough could be produced to run a small generator for a few minutes a day, just to fire up the well pumps for some water into my holding tank, this would be one less thing to worry about. Thanks!!

-- Lou Stein (theknowzone@mindspring.com), April 06, 1998

Answers

Re: Methane production. Mother Earth News did a series of articles on home/farm methane production and use back in the 1970s. I remember a photo of the editor9s father cooking eggs on a gas stove powered by methane. Many used-book stores have back issues. There were also a couple of books from that era on the subject.

-- J.D. Clark (yankeejdc@aol.com), April 07, 1998.

Septic Tanks would not be a good source of Bio-gas bcause they are not agitated and you can't really control the "mixture". If you want a reliable source of Bio-gas you should build a dedicated digester. However, to be blunt, you will need alot of crap to put into it. Kitchen scraps and waste from a family of four would barely give you enough gas to cook 3 meals a day. To run a generator you'd better have 3 or 4 large animals, a dozen pigs, or 100 chickens and you have to make sure their manure is collectable not left in a field. Bio-gas consists of approximately 50-75% methane, 20-50% CO2, and the rest hydrogen sulfide (rotten egg smell) and other trace gases. Only methane is combustible, and hydrogen sulfide eats valves in gas engines and must be filtered out if you run a 4 cycle gas engine. There is a lot of good info on digesters on the web. Do a search under "Bio" and "gas" together. They must be sized according to how much "waste" you have available on a daily basis and agitated once a day. I gave a bad address the other day for the Survival Center it is http//www.zyz.com/survivalcenter/ There is some good info

-- Douglas V. Dorsey (Douglas.Dorsey@PSS.boeing.com), April 08, 1998.

For more info on methane production/use, you might check out http://solstice.crest.org/discuss.shtml. This is part of Amory Lovin9s CREST Institute web site and has a discussion area devoted to an exhaustive exploration of methane.

-- J.D. Clark (yankeejdc@aol.com), April 15, 1998.

Any small farm can make a methane digester very worthwhile. While a digester is unlikely to provide all power needs (solar electric system is best choice here), a digester is an ideal choice for cooking in the summer months when cooking with a wood stove would be miserable beyond belief. Check under biogas and methane digester at amazon.com, or alternatively, go to your nearest large university library, which should have more than you care to read. When I checked the LSU library, they had eleven excellent books on the subject, more than I could read. I have searched, but have so far been unsuccessful in finding any commercially produced digesters in the USA.

-- Ryan Booth (s.booth@usa.net), June 06, 1998.