For the english speaking crowd, a briefly description of some of the ongoing experiments in our micro-farm:

General view of the zones 1 - 2 of the Toca da Coruja (owl nest) micro-farm:

Solar oven/dryer combo:

There are lots of solar oven projects on the internet, but the objective of this experiment is to create a functional and durable solar oven and dryer using the minimal possible external materials. The structure of the oven in made with “Pau a pique” (Wattle and daub?) techinque, using limbs of Mexican sunflower (tithonia diversifolia), a plant that grown scaring fast here. Grass clippings are used as the main insulation. A removable cardboard box covered in aluminum foil is used as the final cooking box. The lid is a salvaged glass door. The wall needs finishing, but we are already cooking meals in it!

The next step is experimenting with other natural insulating materials, trying to produce a working oven without the cardboard/foil layer.

Biogas digester:

How to build a simple, long lasting biogas reactor that uses vegetable waste as raw material? All models of simple bioreactors we found use mainly manure to produce biogas. Using grass clippings and other vegetable matter poses additional challenges to the project. And we also need to figure out ways to improve the air-tightness of the cover, ways to store the gas produced and, if possible, ways to convert it to work in a continuous production mode (now it is in batch mode).

Biodigester loaded with vegetable waste

Biodigester closed with an air tight plastic membrane

It burns!

Water playground:

In this "lab" we are studying low tech alternatives for small scale intensive fish farming and experimenting with aquaponics and associated techniques. The bigger challenges are related with filtration and pumping: What is the least energy intensive system possible? What is the most efficient way to pump water? Is aquaponics a feasible solution?

Pond filters (left) and future aquaponic micro-system (1000l fish tank)

Tilapias in the fish tank, waiting for the aquaponics grow bed

Main fish pond

Agricultural Toolbar:

A Toolbar is a “rig” that permits the attachment of different agricultural tools, and can use different power sources.

We build a small scale rig, to test the concept and experiment with different tools. We tried to keep everything as simple as possible, using wood for the structure and implements made of rebar or simple, easy to find hand tools (hoes, spades, machetes etc).