Performance analysis of a hybrid micro-grid in Somalia : a real case study

This thesis presents a data analysis of an islanded hybrid micro-grid, placed in Somalia. The micro-grid is composed of Diesel Generators, lead acid batteries and PV fields. The installation of the micro-grid represents a rural electrification solution that combines the necessity to guarantee the continuity of the load supply with the willingness to exploit as much as possible the local resources. The analysis is carried out on the basis of the available data collected during the first months of plant operation, from October 2015 to September 2016. The investigations are divided into two periods, according to a significant load variation due to the connection of a new distribution line to the power plant. At first the operation of each generator is analyzed separately by evaluating the most relevant performance indicators; then the interaction of the components is investigated. Thus, the load demand sharing among generators is observed for two sample days, representative of the two periods; from it considerations on the sizing conditions are done. Benefits in terms of fuel consumption, CO2 emissions and money savings are presented. Finally a comparison between the real plant behavior and the one expected in the preliminary design phase with the commercial software HOMER is conducted. To make the analysis significant, since the demand is changed from the one present at the time of projecting phase, further calculations are performed with HOMER: on the base of the same initial model, the performance of first load-period and second one are simulated separately analyzing the affinities and contrasts with the real plant operation.