Technical and economic analysis of solar pumping irrigation system for rural areas in Ethiopia

摘要

Although progress has been made in every area of sustainable energy, energy poverty still involves a large proportion of the population living in developing countries which are often grid isolated and scattered. To overcome this situation, renewable off-grid distributed energy systems, that are sustainable also without donor funds and that can grow together with the community awareness and wellness, still have to be developed. Within off-grid renewable distributed energy systems solar irrigation systems allow to boost local food production, answering to basic needs and improving in a direct way the standard income, thus, representing a first solid step in creating a self-sustaining circle.Starting from a close and comprehensive knowledge of the territory, of the targeted users' needs and social conditions, given by the "Employ project", an irrigation system for a specific area is described. Technical-economic feasibility of different solar pumping solutions (water storage, direct photovoltaic coupling, battery storage) have been analyzed for the irrigation system.Direct solar irrigation system is found to be the simplest, most efficient and lowest cost solution. However, it needs to be properly evaluated with data on water needs and specific weather conditions. Thus, efficient, economic, adaptable and scalable solutions, not only in Soddo, Wolayta Region, but even in other rural areas of neighboring regions can be implemented. The study aims to underline that smaller and simpler systems, if studied in-depth and sized in accordance with the local conditions, can represent a solid base to build off-grid modular, scalable and replicable solutions for developing countries. This avoids the initial barrier created by high capital costs and fight the dependence on external grants, fostering thus a more comprehensive, step by step development.