The Green Machine

Mcgill J Med. 2009; 12(2): 12.

Stefanie Thibert(1) and Van der Jennifer Wee(1)
1 – Queen of Angels Academy, Montreal, Quebec, Canada 
*Note that each author contributed equally to this project


The purpose of the project was to design a composter that will create humus in two weeks instead of the usual two years. This design will reduce waste going to landfills, therefore reducing the pollution entering the atmosphere and surface waters.

The Green Machine consists of an outer box made of plywood which acts as a shell to both chambers, an air filter and the electric devices. This composter was built in six general steps: the assembly of the upper mixing chamber; construction of an outer box; building of an air filter; assembly of an inside of the box; doors and the electric devices. Decomposition begins within the upper mixing chamber, with the help of microorganisms, during the first nine days. The curing process then continues in the lower chamber for the remaining five days.

The Green Machine was a success for it created organic soil in fourteen days. The air filter was effective and there was sufficient microbial activity. The pH, the moisture and the temperature were in the appropriate range during the thermophilic and mesophilic decomposition.

This composter is a major improvement upon traditional composting techniques. It is simple to build, effortless to use, convenient and has both financial and environmental benefits. This composter is economical since it produces organic soil for the garden; therefore, eliminating the need to buy soil. On a larger scale, if organic wastes are no longer being sent to landfills, less garbage will be put out weekly, thereby reducing the amount of workers needed.


To whom correspondence should be addressed:
Stefanie Thibert
Email: purpleelephantfaces@hotmail.com
Jennifer Van der Wee
Email: laughingpinklions_dancer@hotmail.com