Another heat wave running through, so I've been trying to organize my thoughts around what my ideal closed-loop system entails. This isn't something that I can execute perfectly out here because of elements that are out of my control, but I'd like to achieve something vaguely akin to this. Here's what I've got (you'll have to excuse my crude drawings.)
This revolves around a composting
toilet system not unlike Paul's current iteration. The difference being that instead of using an off the shelf trash can, it uses a custom bin with at ramp that spirals up along the outside (or a ramp could probably be fashioned out of PVC cut lengthwise.) That's so that the black soldier fly larvae that are processing the waste can exit when they're mature. Not only would human waste be fed to the system, but also any food waste that isn't suitable for feeding directly to animals (butchering waste, spoiled food, anything toxic to livestock, etc.) The black soldier fly larvae are and to exit through a pipe at the top of the bin and walk along it before dropping directly in the animal enclosure where they can be eaten by chickens. I'm curious about using biochar
as a carbon
source/odor control agent in such a system. A drain in the bottom allows the effluent to exit through the existing septic system. To keep adult black soldier flies from coming up through the toilet an RV style toilet could be used and a small asking of gray water used to flush solid waste.
is diverted into a storage tank where it can be drawn off as needed as a liquid fertilizer as well as being plumbed to a pond
where it can be used to fertilize azolla/duckweed. A swivel pipe allows control over the water level in the pond, with overflow being plumbed to drain into the existing septic (a reed bed might be another option.) Fish might be another option in the duckweed/azolla pond, but care would be needed to ensure that they don't overconsume the plant population.
Animal safe food waste, biochar, weeds, hay
, leaves, and any mix of other carbon rich materials are added to the animal enclosure as part of a deep litter composting system. The azolla/duckweed contribute a major part of the diets of both chickens and rabbits
, as do the black soldier flies contribute to the diets of the chickens (and help control waste and their associated odors.)
The bathroom would be situated above a wallipini greenhouse
which then houses the black soldier fly bin and the azolla pond so that warm enough temperatures are maintained for year round production. At peak production, as bucket
can be hung from the black soldier fly outlet pipe and a portion can be dried for winter feeding. So too can a portion of the azolla be dried for winter feeding when it's at peak production. The wallipini provides the conditions for growing exotic tropical and subtropical fruit.
cannot be grown over the septic field, it's instead arranged in a series of narrow rows of vegetables (maybe not roots
, though I don't think it's a problem with a functioning septic system? But at least seeds, grains, fruits, and possibly greens) all arranged on contour. The septic system provides the area with consistent moisture for steady growth. The rows would be planted by broadcasting a seed ball mix that's appropriate for the time of year. Shallow swales could act as fit paths on the uphill side and wood
could be buried in the berm
as a kind of micro hugelkultur. In between the vegetable rows are wide paddocks which the chickens would have access to one at a time. 7 paddocks match an adjacent 7-year coppice system and allows the chickens access to each paddock for a week, rest the paddock for a month, and then scythe it ahead of the chickens being put back on it. About a quarter of the scythings would go to mulching the contour bed above the paddock, about a quarter would be fed fresh to the rabbits in the enclosure, and about half would be dried for winter feeding/bedding.
Vegetables would be planted roughly on a one week succession so that you're generally only harvesting from the row that's above the paddock that the chickens are currently on. That way any vegetable refuse or surplus and weeds could be removed and fed to the chickens as you harvest simply by tossing it over the fence
. An abundance of corn, amaranth, sunflower, etc. can be grown in these rows as a supplement to what the chickens are foraging and bring fed in soldier fly and azolla. Comfrey and other perennial
herbs could be planted on the downhill side to stabilize the contours and provide additional mulch/forage.
The animal enclosure has a series of gates that allow access to the individual paddocks. The gates are either high enough that the chickens can hop out but the rabbits are contained, or else a short inner fence
is added that the chickens can hop over to get to the gates but the rabbits cannot. One or more large mounds of dirt gives the rabbits that opportunity to burrow and make natural nests that can drain urine from the kits, unlike with plastic or metal nest boxes. It also allows them to regulate their temperature. The rabbits are fed on azolla/duckweed, fresh and dry hay, and whatever vegetables, seeds, and grains are tossed into the enclosure and they feel like nibbling, though such things will mostly be for the chickens.
The enclosure will be maintained as a deep litter system with the inclusion of biochar to soak up excess nutrient. One or more times a year the biochar enriched compost
can be removed and added to the garden beds
Adjacent to the septic field/garden/paddocks is a 7-year coppice system, also arranged on contour with small swales for walking paths. The coppice system includes nitrogen fixers like black locust
as well as nuts like hazel and chestnut. Each year one row is cut to the ground. Anything that's a suitable diameter will be used as fuel for a rocket mass heater
. For any unsuitable material, a pit will be dug in order to process it into biochar (could also be used for mushrooms
, tools, etc.) If my experiments with clay pebbles price useful, the biochar fires week also be used to fire clay (I'm not sure how quenching the fire will affect the clay, but she it just needs to be fired, not pretty, I suspect it will be sufficient.) The fires can be a maybe weekly event where folks come to roast meat and vegetables over the flame and tend to the burn. High fertility waste could be buried in the pit and a new pit dug every burn or every few burns (since it's likely to fill with water in the rainy season and become unusable.)
In between the rows of the coppice system, a food forest with fruit trees and other perennial species can be planted (assuming there's enough space between the coppice rows to accommodate trees. At the end of the season you can extend chicken
access into this area so they can clean up fallen fruit and break the cycle of pests. Alternatively, the coppice system can be placed on the opposite side of the animal enclosure so that you can keep the chickens off of the paddocks when they aren't actively growing or after only growing slowly; or so you can limit their access to the food forest so they don't have time to do irreparable damage.
Initially the paddocks can be managed with electric poultry net, moving the net to each new paddock each week, but permanent and/or living fence could ultimately be employed (and could be another source of fodder.) A living fence may or may not allow enough light to hit the vegetables, depending on how it's designed and managed. Goats or sheep could potentially be added to the system if designed appropriately.
The ideal house would be long and narrow and oriented to minimize exposure to the western sun. The wallipini greenhouse
is along the south wall of the house. The animal enclosure is arranged on the north and east of the house to supply adequate shade during the hottest part of the day. A deck on the north and east of the house serves as a shady spot for the humans to hang out on hot days and also doubles as a shelter
for the animals. The kitchen opens onto the deck where food scraps can be tossed out to the animals as one prepares food. All of the plumbing is in the east wall and could be set up on a rain collection system. At the very least a rain barrel supplies water below the deck for an automated watering system for the animals. There's access to the cellar from the kitchen and access to the animal enclosure from the cellar. This provides convenient access to eggs and meat, as well as a handy place to drop off fruits and vegetables as one comes in from the garden
. An entryway with a secondary door ensures that animals don't run into the cellar while you have your hands full, provides a storage area for animal feed, a place to take off muddy boots
or clothes, and a deep sink for washing produce.
The bath, as noted earlier, sits above the greenhouse
so that the bin for the composting toilet stays warm enough in winter for the black soldier flies to continue reproducing. A rocket mass heater
is placed along the south wall of the house so that it can absorb the heat of the sun and any waste heat from a fire goes to warming the greenhouse
. The barrel of the rocket mass heater
is oriented toward the kitchen so it can be used to heat water, stock, etc. The bedrooms have direct access to the deck, because why not? Makes it easy to pop out and check on animals, take a call, take a smoke break, or just be able to jump out of bed and start your day without having to navigate the rest of the house. Also a good design for any potential woofers/couchsurfers/airbnbers that allows them to come and go.
The animal enclosure and garden/paddocks obviously aren't to scale. A presentation from the National Center For Appropriate Technology
suggested 50-100 chickens per acre
, so you'd have to figure out the maximum size of your flock and how much total area you'd need for that many birds. Divide by 7 to get the area per paddock. Long and narrow maximizes the amount of garden space but isn't a very efficient use of fence, so it's a trade off. The T-shape for the enclosure isn't strictly necessary, but does maximize the amount of deck that can double as shelter for animals while minimizing the amount on unvegetated space/space that needs to be mulched. And of course, this still leaves plenty of zone 2/3 for additional food forest beyond what's present in the coppice system.