Design and simulation of a standalone solar energy system by PV SYST

Abstract

Solar energy is a clean and reliable energy source, particularly in remote areas, where the energy supply is limited. This study aims to design and simulate a 4.95 kW off-grid solar energy system for an automated milking and milk-cooling facility facing power supply issues. A preliminary design was created to ensure that all the necessary data were available for the use of the PV SYST 7.4 software to design and simulate the system. Performing a system simulation helps to identify system flaws and reduces problems and losses during operation. The long-term simulation investigated off-grid photovoltaic system performance and reliability, saving a significant amount of time and money by addressing any issues or flaws before installation. The array's effective output energy reached 23.42 kWh/day, and the system delivered 21.14 kWh/day of useful energy, which is equal to the energy required by the facility. The difference between the output effective energy of the array and the useful energy delivered by the system can be attributed to the losses, with the most significant being the heat-related array losses (10.67 %) and battery efficiency losses (4.99 %). Throughout the year, the average state of charge of the battery was 59 %, which contributed to extending its lifespan. Additionally, the solar fraction achieved an optimal value of 1, confirming the effectiveness of the solar energy system design. This implies that the system can power loads without the need for a back-up power source. • The proper and efficient design of standalone solar power plants ensures efficient and reliable operation. • PVSYST's long-term simulation saves time, effort, and costs by identifying potential issues or flaws before installation. • The PV system exhibited numerous losses, with the most significant being array, unused energy, and battery losses.