Evaluation of Low-Cost Evaporative Cooling Technologies for Improved Vegetable Storage in Mali -Presented at the 2018 IEEE Global Humanitarian Technology Conference (GHTC) in San Jose, CA
In Mali, a lack of affordable and effective post-harvest vegetable storage solutions often leads to vegetable spoilage, loss of income, reduced access to nutritious foods, and significant amounts of time spent traveling to purchase vegetables, particularly in rural communities.
This research study investigates the potential for non-electric vegetable cooling and storage devices to address the post-harvest storage challenges in rural Mali. The two classes of devices evaluated in this study are commonly known as "Evaporative Cooling Chambers" (ECCs) and "clay pot coolers", which rely upon the evaporation of water to create a cooling effect. In this study, we used a combination of electronic sensors and structured user interviews to gather information about users' needs for improved post-harvest vegetable storage, current methods of post-harvest vegetable storage, and the performance of the evaporative cooling devices.
The evaluation of six types of ECCs and clay pot coolers provided insights into user preferences as well as performance related to metrics such as interior temperature and humidity, ease of watering, and protection from animals and insects. The results of this study indicate that low-cost evaporative cooling devices such as clay pot coolers and ECCs have the potential to benefit both off-grid populations with limited access to electricity and on-grid populations with high electricity and/or high equipment costs for refrigerators.
The reduced post-harvest losses - achieved through the improved storage environment - can lead to impacts including monetary savings, less time spent traveling to the market, and increased availability of vegetables for consumption. Based on this research, the key factors (operating conditions, need, and value) that should be assessed to determine the suitability of evaporative cooling devices for a specific context were identified and discussed.