This project describes the process conducted to develop an off-grid food processing system reliant on solar energy for micro-enterprises in Johannesburg, South Africa, following the Human Centred Design process. Around 20% of South African households do not have enough food available to meet their daily dietary requirements, while food processing and preserving allows for it to be available during dry seasons. Furthermore, this decreases post-harvest crop losses. Food processing relies heavily on energy consumption, mainly due to heating the food or the boiling of water to sterilize bottles or jars. Energy is often expensive, unreliable, and sometimes unavailable. This research project was conducted in four phases, with the collaboration of three micro-food-processor enterprises as well as experts in the field of renewable energy. The four phases consisted of problem identification, followed by concept generation including sketches and prototypes. In the third phase laboratory prototype testing was undertaken which was followed by the last phase, participant testing. During the first phase, a literature review was conducted to understand the principles and methods to preserve food and the energy requirements of the machinery used to process food in micro-enterprises; recognizing that solar energy is a viable source of renewable energy in Johannesburg. With this background, field research was conducted with three micro-enterprises that preserve and process raw ingredients into Chilli Sauce, Body Soap, and Ginger Beer. During the visits, the step-by-step process was observed, and the machinery used and their energy requirements were noted. The need for a stove, a kettle, and a blender was identified as the main machinery required in the process. Based on the requirements of energy identified for these machines, the second phase consisted of the conceptualization of the three appliances: a Heliotropic Solar Stove, a Solar Thermosiphon Water Heater, and a Photovoltaic Food Processor Workstation, with a prototype for each machine being developed. During the third phase, the prototypes were tested in a laboratory setting, evaluating how effectively they performed the required activities. Finally, the fourth phase consisted of the testing of the prototypes in the field, with the participants of the study preparing their products and receiving feedback during the sessions. This allowed for final improvements of the prototypes to be considered in a final design outcome.

Thesis OPEN ACCESS