Ever heard of a biodigester?

[Paschale]

I heard on the radio about a group of people down in Guatemala who are working with the indigenous Mayan cultures to help them become somewhat self-sufficient through shop built technology.

They were talking about communities that use biodigesters, something I've never heard of before.  Apparently, they'll put compost and manure into these things, which will produce enough methane gas to power their gas stoves for four hours a day.

That's pretty impressive!   8)

I just wonder how much poop you need to get her going...   :D

[beenthere]

Similar (??) ideas on farms in the US have been promoted and tested for at least 30 years, but suspect not so successful that many farms do it, or use it. But sure sounds like a good idea.
Bottom line, like many good ideas, is that they take too much investment money that needs a payback to be more than just a 'good idea'.  Most a them come from grants to pay for the development and an application or two, which doesn't fly much beyond this point. Don't know that for a fact, but also don't see much methane being used from farms either. Still mostly seem to be running on diesel fuel. 

[Fla._Deadheader]

It's used for lighting and cooking.  Biggest drawback in the states is, ya have to actually "tend" the thing, occasionally. Energy is cheap and plentiful in the states, and VERY convenient. Take away any one of the three, and you will see more people "into" it.  : :

  Tap into your septic system and burn the Methane you produce.  : :

[Tom]

I was going to say that I had a bio-digester as a septic tank.  I just didn't open it up and tap the gasses.

When Tyson Chicken was in the neighborhood, and before, the chicken farmers built digesters to take care of the dead chickens in the chicken house.  The regular day had a lot of them.  They would die from heart attacks (growing too fast), broken wings, legs (Developing too much weight before the bone matured) and being pecked.  These were thrown into big containers similar to septic tanks that were kept on the back of the farm.  Supposedly, they would be pumped out on occasion and the contents spread on the fields.  Part of the program was for the methane to be tapped to heat the houses, but I don't think any of the farmers ever did it.

[Fla._Deadheader]

My cousin had a "Dry well", where they "used" to dump dead one's. Quit using it before I started hanging around. Switched to Rhode Island Reds and the premature dying was cut DRASTICALLY.

  Anybody ever been on their roof, and smelled a "gas" coming from a vent pipe ??? 

   Methane.         

[stonebroke]

It is pretty much a mature tech. Big dairy farms are starting to use it where they have odor problems. One drawback is on a large scale it costs a lot of money( 250,000$ to several million)

[Woodcarver]

There's a dairy a couple of miles down the road from us that has a digester.  The methane from the digester is burned to generate electricity.  The dairy generates all of it's own power and sells the excess to the local utility. It's been in operation for two or three years.  I'm probably using cow power as I type this.

We buy the dry matter from the digester by the pick-up load to use as a soil amendment in our vegetable garden and flower beds.  Some phosphorus and potash in it and lots of organic matter. The heat of the digester sterlizes it and kills any weed seeds that might be in it.

[Tim]

There is a farm near here that has built a bio digester several years ago. They are generating electricity from it with diesel back up. They are generating enough electriciy at times to sell into the grid.

They recently wanted to expand their digester and the Ontario Ministry of Environment and the Ontario Municipal Board jumped all over them. This was last summer. I don't know how they are fairing with thier plans. I guess the MOE and OMB would rather have all that methane exaust into the atmosphere otherwise they would not be able to justify the 2 grand per week pay check each of them receive...  >:(

I am currious if there would be enough gas generated off a septic tank to warrant an investment into a smallish generator to power a few lights in the house...

About a year and a half ago, Lore and I were shingleing a roof below Bancroft on a cottage. (You can see the pictures on my site) Lorne was working near the stink pipe. I hear this wretching and complaining about the smell... I hear the technicolour burp over the edge of the roof... Lorne tells me that I am not paying him enough to work around that pipe... I guess tht he was still feeling the effects of the beer, beans and rye bender from the night before, 'cuz he wasn't thinking all that clearly. I traded spots with him, stuffed the stink pipe and finished that part. Honestly though, for the smell coming out of that pipe, they could have generated enough elec tricity to compare with a small nuclear reactor.

[Thomas-in-Kentucky]

I built a small methane digester last fall, and it worked.  (I have on average now, 40 head of cattle).  I plan to scale up the experiment this summer.  Temperatures have to be high enough for the process to work, and I don't have a heating capability on mine - yet, so this is a warm weather hobby.  This summer, I hope to build a digester that will hold 1,000 gallons of cow poop.



I wrote about it on my blog. 
http://massiehouse.blogspot.com/2006/09/butt-holes-contributing-to-self.html
Anyone have any advice regarding how to build a small scale digester??

-thomas