Low cost post-harvest technologies for rural communities
A native farmer named Gilberto Tethere in Cabo Delgado Province invented the Zero Emission Fridge for Rural Africa (ZEFRA) by reconstructing a metal silo using only locally available low-cost materials and applying traditional construction techniques.
The basic design of the ZEFRA is a weaved bamboo structure, meticulously covered with clay on both sides. The shape is cylindrical and the two openings (for filling and emptying) are closed with tightly fitting clay-covered hatches. It stands on a base that incorporates vermin traps to protect the grain from rats and mice, and under a simple shelter to maintain cool, dry and even conditions.
The clay carcass of the silo seals the seeds in an almost hermetic chamber and improves the effect of the organic, herbal repellents (produced from ashes, eucalyptus tree and other local plants, and used to inhibit insects such as the granary weevil (Sitophilus granaries L)).