How to make the most efficient compost heated shower

This is a thread intended for people to share their experiences building and observing compost piles that are used to heat water. I am curious about the specifics on how to build the most effective pile for heating water (lasagna method,chips/manure, etc.).  I have seen several examples of compost heated showers on youtube and in writing and i would like to hear peoples thoughts about how you have or would specifically design/construct the most efficient pile that:

1) produces very hot water
2) remains hot (functional) for a long period of time
3) gives the highest amount of hot water per extended use
4) has the fastest recharge
5) produces rich finished compost
6) stacks many functions and tie into other systems
7) provides other yields...

drawings of the design of the pile or system itself would be appreciated.

I have no experience, but I saw this trailer for Geoff Lawton's Permaculture Soils DVD and he mentions in it 6-8 weeks of heat etc.  The dvd itself would probably have some answers.

I would aim for a pile with lots of coarse browns, especially twigs or chipped brush, which had been thoroughly soaked in water prior to the addition of greens.

My rationale is:

* coarse materials have more loft, and allow a larger pile to remain aerobic without turning (since any heat exchanger would complicate turning)
* wood holds a lot of water, meaning a less-thirsty pile, and a pile with greater thermal mass (for more throughput with less retardation of compost metabolism)
* carbon from coarse materials isn't immediately available, and so the C:N ratio is effectively lower for the first part of decomposition, but remains more constant as decomposition proceeds

There are lots of options for a heat exchanger. You might build a large reservoir into the center of the pile, like a 55 gallon drum or an old hot water tank, or you could harvest heat through the walls of a garden hose, or maybe look into a salvaged heat-exchanger of some other type, if it doesn't contain heavy metals: home heating radiator, car radiator, the drained rear coils of a scrapped refrigerator...I think it will really depend on what's most available.

I've done some work in this area:
http://www.puffergas.com/pile/pile.html

What are your winters like?

mild, not really any frost...i am in santa cruz, CA zone 9a/b

Sounds doable.

Check this download book out:
http://www.biomeiler.at/explorer/Downloads/AnotherKindofGarden.pdf

Gotta go.

Later.

One of my favorite bloggers is trying to do his whole home's hot water, and just posted on the start of his project. He feels he needs four tons of green brush, with 1" or less trunk diameter. His neighbors are willing to offer that, if he cuts & hauls.

One Straw blog: L'eau chaude

paul wheaton wrote:

this is so fabulous!