Cost Optimization and Design of a Hybrid Distributed Generation System for a DC Microgrid

An enormous percentage of the world's population dwells in energy-underprivileged communities that are isolated, remote and sparsely populated. The hybrid energy systems (HES) based on renewable energy (RE) resources of increasing interest such as photovoltaic (PV) and wind energy are considered to be an effective option to electrify these communities. This is pertinent for areas with good solar radiation potential and sufficient average wind speed. This paper proposes a DC microgrid made up of a solar-PV/Wind/Diesel hybrid system with a backup battery bank. The proposed DC microgrid was modelled, simulated and optimized for Oluundje village, a remote rural area in the Northern part of Namibia. The load forecasting and system modelling process involved a site survey to collect the load demand, wind resource, and solar radiation data. HOMER software was used for system modelling and cost optimization of the system. In view of the simulation results, it is found that the net present cost (NPC), the cost of energy (CoE) and a payback period of the optimal system are $459 545, $0.248/kWh and 4 years, respectively. In view of the economic and environmental analysis, it is apparent that electrifying energy-deprived communities using DC microgrids based on hybrid systems with numerous RE sources are beneficial due to the lower operating costs and the environmental friendliness associated with these hybrid systems.