Design of Sizing Algorithms for a Direct Current Off-Grid Photovoltaic Installation

This paper presents a novel methodology for the sizing of an off-grid photovoltaic DC microgrid with emphasis on cost reduction and design simplification. The sizing algorithms used to design and build each of the subsystems of the installation are also presented and validated by the SimPowerSystem tool. The methodology has been tested on a real building, the hall of residence from the University of Deusto, and its novelty lies in the capacity of supplying electricity to a building, which average daily consumption is around 41.10 kWh, located in one of the regions of Spain with low solar radiation. Experiments provide satisfactory results by reducing both the necessary number of panels around 46% and the energy storage down to 50% in comparison with the sizing methods established in the literature. Our proposed methodology includes highly adaptable algorithms that enable a rapid design and posterior adjustment of a new installation for newer buildings.