A key part of my integrated system is the compost.  Nutrients must be recaptured and returned to the soil.  My compost will include humanure, animal manure, vegetable matter, old newsprint that would otherwise go to a third party recycler, and an algae to invertebrates fish feed system.

Terra PretaEdit


climate kiln for production of Terra Preta.

Terra Preta is soil that has been treated with carbon rich material created by burning cellulose in an oxygen poor environment.  The carbon serves as a moisture and nutrient sponge that enriches the soil by allowing it to make the most of the water and nutrients present while creating an enormous amount of surface area for colonization by beneficial microbes.  One way to obtain it is using a kiln such as the ones sold by RE:CHAR.  A kiln similar in the one in the picture could be used to reduce surplus cellulosic material that is not edible to terra preta.  This has additional benefits of speeding up the composting cycle and of sequestering carbon into the soil for thousands of years.

Additional efficiency can be created by adding a steam engine to capture the heat energy.  Suitable steam engines or at least plans for building them are available from Green Steam Engine.

The steam engine would also be suitable for converting heat from solar concentration and the climate kiln could be run after dark or on inclement weather days.

Composting logEdit

Plenty of  heat in the tumbler but no visible changes yet. Keithjd21 (talk) 01:08, August 8, 2013 (UTC)

The tumbler gets too hot to touch in full sun. Keithjd21 (talk) 00:20, August 5, 2013 (UTC)

Tumbler 12 cu ft

90 gallon capacity compost tumbler

The big black thing is a new compost tumbler of about 90 gallon capacity.  A  cylinder this size will in fact fit in the back of a 2002 Chevy Cavalier.  Barely.  After tilting the front seats forward and using a sandal as a shoehorn.  Getting it back out was the real challenge.  This structure is too hot to touch after half an hour in full sun.  I will be looking for a thermometer that is accurate in the 100+ range and determining if the interior is topping 150 degrees.  If so, no more boiling poo as the main composter will pasteurize daily.

Bucket lined with newsprint

Bucket lined with newsprint

The bucket on the right is lined on the bottom with newsprint.  The idea is to deposit poo in the bucket and while wearing rubber dish gloves retrieve the paper, hopefully without touching any poo so the whole package can be transported for compost.  Basically a single use composting toilet.  If this is practical, I will remove the bottom from a bucket and add a square bottom with a drawer that accepts newsprint more readily.  Maybe add an airtight bucket nearby to hold a day or twos volume in the event of heavy rain.  I'll affix a toilet seat to the top of the bucket for those days when you need to sit and ponder.  I'll be looking for a separate solution for urine collection.  My current method of using old Gatorade bottles (due to the large neck) works for me but would be problematic for female guests.  Ideas anyone? Keithjd21 (talk) 00:03, August 4, 2013 (UTC)

The anaerobic bin is expanding.  The material is swelling upward leaving about a half inch of material that has been shaped like dog food or cranberry sauce coming out of the can.  I'm presuming that swelling of the fibers indicates microbial action.  Sufficient to lift hundreds of pounds of wet newsprint. Keithjd21 (talk) 17:00, July 28, 2013 (UTC)

New part of the experiment.  One 30 gallon can has cracks in the bottom and is leaky and thus drains well.  The other is new and fully sealed and water tight.  I soaked them both good and let one drain and the other develop a quarter inch of standing water on top.  The sealed container will go fully anaerobic.  We'll see which method breaks down newsprint fastest this way. Keithjd21 (talk) 00:34, July 24, 2013 (UTC)

Even more rain today.  Have covered the bins as they are getting soupy. Keithjd21 (talk) 00:02, July 22, 2013 (UTC)

Minor hitch in my process.  When I boil to pasteurize, it turns if you don't stand by to stir, the poo at the bottom scorches to the pan.  I have the pan soaking outside now.  Going to try applying  a thin layer of vegetable oil to the bottom to see if I can overcome this.  Might have to invest in some kind of nonstick coating.  Ideas? Keithjd21 (talk) 00:09, July 18, 2013 (UTC)

Cell pic of mushrooms in bin. Keithjd21 (talk) 12:22, July 16, 2013 (UTC)

A pair of mushrooms that sprouted last night. Already about 6 inches tall.

Compost has mushrooms on top now.  I have to run for now but will try to upload a celly pic tomorrow. Keithjd21 (talk) 00:03, July 16, 2013 (UTC)

The compost bin which is a 30 gallon plastic trash can filled with newspapers, a half gallon of pastuerized humanure, and topped off with a couple inches of finished compost looks like it is not doing anything.  Except I noticed today the upper most layer is about 3 inches lower than before.  Something is going on and sooner than expected as the experiment was started only 29JUN2013.  Exactly two weeks later, I have visible evidence of microbial action. Keithjd21 (talk) 01:55, July 13, 2013 (UTC)

I have been trying to source materials to build a compost tumbler but no luck so far.  May break down and buy one. has a 43 gallon unit that is available for $145 including shipping.  Assuming 5 cycles a year, compost would be about 50 cents a gallon, with the cost falling by half each additional year the tumbler is serviceable.  Keithjd21 (talk) 09:24, July 6, 2013 (UTC)

Compost has attracted very small flies or possibly gnats which is what my compost usually does.  They usually disperse after a week or so.  This tells me the boiling trick does not eliminate all odor however even though I cannot smell it. Keithjd21 (talk) 23:50, July 1, 2013 (UTC)

For anyone who wants to try to duplicate this experiment...turns out newspaper swells quite a lot when watered in.  I now have an overly full trash can.  I'll keep that in mind when adding fresh newsprint in the future. Keithjd21 (talk) 22:12, June 30, 2013 (UTC)

I have about 25 gallons of nearly finished compost in a 30 gallon plastic trash can.  I started a second 30 gallon can today.  That can was filled with grass clippings, newspapers, and about 0.5 gallons of my own feces that had been pasteurized with heat.  The feces went in after the bin was about 3/4 full and received a few handfulls of my near finished compost to seed microfauna into the system for a quick start.  I watered it in well.  Keithjd21 (talk) 00:52, June 29, 2013 (UTC)