## 3 Microgrid Sizing Approaches
### Commercial Software
Research in [44] explored integrating and optimizing multi-microgrids utilizing HOMER Grid software in Goma, DRC. Considering technical and economic aspects, the objective was to minimize the NPV over a 12.5-year horizon. The study highlighted the feasibility of a system configuration without PV, which achieved nearly the same NPV with a significantly lower initial capital cost, albeit with higher operational and maintenance expenses affecting the levelized cost of energy (LCOE). Furthermore, the study in [45] utilized HOMER to determine the optimal configurations for PV/Diesel/Pump-hydro and PV/Diesel/BESS systems. This study emphasized calculating payback periods while identifying cost-effective solutions for energy systems. The study in [46] developed a techno-economic methodology for the development of a standalone, renewable energy-based electric vehicle charging station (EVCS) in Qatar by employing HOMER for optimization. The aim was to minimize installation and lifetime operating costs among all technically feasible configurations that met the daily EVCS demand. The optimal configuration's NPV was found to range between $2.53 M to $2.92 M, with electricity costs varying from $0.285 to $0.329 per kWh. In Vietnam, the optimization of EVCS in major cities was the focus of [47], using HOMER Grid for analysis. The study aimed to reduce NPV and enhance efficiency by considering local solar conditions and economic factors. It proposed optimal system configurations for Hanoi, Da Nang, and Ho Chi Minh City, highlighting the impact of solar irradiation on investment and operational performance. Additionally, the study in [48] optimized an isolated microgrid for rural electrification in India using GA and HOMER. The study aimed to minimize the NPV and the LCOE by comparing various hybrid configurations. The GA optimization yielded an optimal solution with the lowest LCOE at $0.163 per kWh. The potential of DER in off-grid microgrid optimization was explored in [49] using MILP and HOMER. The study aimed to minimize the NPV while highlighting significant cost savings and efficiency improvements from implementing DER. Lastly, HOMER Pro, an advanced version of HOMER [50], was used in [51] for optimizing hybrid microgrids for green hydrogen production in Fiji. The study focused on achieving the most cost-effective configuration for hydrogen production, critical for powering fuel cell buses, aiming to minimize the NPV. The economic viability of microgrids across various geographic locations and with different DER combinations has been assessed using HOMER software. Notably, analyses have been conducted on a PV-WT-hydro-biodiesel hybrid system in India [52], a PV-WT-diesel system in Sri Lanka [53], and a WT-biogas hybrid system in Canada [54]. These studies highlight the adaptability and effectiveness of HOMER in optimizing microgrid configurations to improve sustainability, cost-efficiency, and energy reliability. The advantages of HOMER software include:User-friendly interface;
* Comprehensive financial analysis capabilities, including cash flow analysis and payback period calculations;
* Integration capability with Geographic Information Systems for enhanced project planning and site selection;
* Advanced sensitivity analysis to evaluate the impact of variable parameters on project outcomes;
* The ability to process hourly data for detailed and accurate modeling of energy systems.