Human centred design of an off-grid food processing system for micro-enterprises within Johannesburg

M.Tech. (Industrial Design)Abstract: This document 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 sterilise 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 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, being 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; recognising that the 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, the machinery used and their energy requirements were noted. The need for a stove, a kettle and a blender were 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 conceptualisation of the three appliances named as: 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