Optimal design for an electrical hybrid micro grid in Colombia under fuel price variation

In many ways, the availability of electrical energy is associated with the degree of development of a society. In spite of the recent technological advancements, many Latin-American countries remain with a wide number of towns isolated from the main grid of their electrical power systems. Colombia is one of these countries, and the implemented solutions rely mainly on the use of diesel generators. One possible solution approach includes the expansion of the existing infrastructure with the use of renewable energy sources in isolated microgrids. In this paper, three optimal designs for an isolated hybrid microgrid in the Colombian community of Unguía are proposed using an iterative optimization technique, the interior-point algorithm. The hybrid microgrid is composed by a diesel generator, photovoltaic panels, wind turbines, and batteries. In addition, each design is obtained for a given diesel generating cost. In each design the number of photovoltaic panels, wind turbines, and batteries for a given type of element are calculated. The unmet load and the power delivered by the diesel generator are calculated for each time interval. The optimization objective is to minimize the total system cost. The optimization results show that for a certain diesel cost, the system obtained only uses renewable energy and storage to supply load demand, although the diesel generator infrastructure is already in place, and no initial investment costs associated with diesel generation were assumed.