Letter Re: A Composting Hot Water Heater Experiment

Dear James Wesley,
The following is a method of obtaining hot water in an off-grid situation. Even more exciting than the 6.5 earthquake this week was our new hot shower! We still have “no” indoor plumbing on our rather recent homestead. Showers in hot weather consist of a hot garden hose. Cold weather requires heating water on the stove and pouring it over ones self while standing on the yurt porch. Or just a spit bath with a washcloth if it’s too cold to stand on the porch.

But I have seen what other clever off-grid folks cook up for showers, and so we now have a compost water heater. We built a pile about 8′ across and 2.5′ deep, then laid a 300′ roll of 3/4″ poly pipe in the center and piled on more leaves, manure, hay, coffee grounds and household scraps, leaving the ends exposed. Hooked one end up to the garden hose, and the other end to an outdoor shower
stand I bought some years back but never used. We set it up inside the greenhouse so it is private and weather protected.

Presto! After “cooking” for a few days, our water was up to the mid 90 degree range, and 300′ makes a decently long shower. By today,I found that it is hot enough to require mixing in some cold water! I have never built a compost pile quite this large before, but most of my big piles have been getting up to 150 – 160 degrees for a week or more, then gradually cooling back down. We expect to get a few
weeks worth of hot showers out of this pile. As it begins to cool down into the low 90s again, I will build another pile adjacent to it and use the second 300′ roll of pipe we bought on sale awhile back. By running the pre-warmed water through the second pile, we should have a great supply. Sheer luxury. And free, except for the labor, since all the equipment was purchased months or years ago and for other purposes. And when it is all said and done, I’ll still have the compost for the garden. Kinda helps balance out all the gray skies and mud. – Respectfully yours, T. & D. in California