Optimal design of grid connected pvwind power generation for urban healthcare facility using homer environment

Abstract

Microgrid combines effective distributed generation schemes and interconnected loads in a specific location. In modern power distribution systems, microgrids can offer the opportunity to increase the amount of distribution generation and delivery of electricity when there are uncertainties with the national power grid. Hospitals are among the most energy intensive commercial buildings due to the significant air management requirements and high electrical load Equipment. Although hospitals have integrated additional on-site power generation to alleviate this situation, the problem of energy costs remains high. As a result, this study attempted to design optimal grid-connected solar PV, wind and battery storage system focusing on a typical urban healthcare facility in Ghana; Kasoa Polyclinic (KPC). To achieve the objectives of this study, the load profile data, methodological, economic data and components cost details are simulated using HOMER Grid software. HOMER Grid is the only demand rate reduction and optimization tool that considers generators as a peak shaving method. Study Results showed that the annual utility bill (base case) was US$213,439.90 with a Total Net Present Cost (TNPC) of US$7,004,608 and Levelised Cost of Energy (LCOE) at US$0.2414 with 558.8tons/year of carbon dioxide emissions. The optimization (winning case) results also showed that the grid-connected hybrid system (solar/wind with battery storage) was more reliable and cost effective among the five cases compared to the base system. Thus, the reduced TNPC of the system at US$3,098,562 and the LCOE of US$0.093/kWh. Savings over the life of the project was US$4,901,516 with reduced carbon emissions of 70.0 tons/year representing reduced emission cost of 2,100 Euros, translating to a monetary savings of 15,564 Euros (approximately US$18,454/year). Therefore, this optimized model can be adopted to address technical, budgetary and environmental pressures.