Increasing Storage Battery Lifetime in Autonomous Photovoltaic Systems with Power Generation Structure Varying Throughout the Year

摘要

This paper substantiates the use of photovoltaic systems with power generation structure varying throughout the year. This research topic emerged from an in-depth analysis of the operating modes of autonomous photovoltaic systems located in Siberia and the Russian Far East. The paper gives a detailed and concise description of a methodology for modelling such a system with account of issues relating to the operational sustainability of diesel and solar power stations in autumn and winter. In spring and summer, autonomous photovoltaic systems operate using the standard power accumulation algorithm whereas the diesel power station serves as a stand-by power source thereby increasing the lifetime of storage batteries, reducing the number of their replacements and cutting down costs through discounting. The overall levelized cost of energy drops off significantly too. The paper presents the results of modelling an actual autonomous energy system in which a solar power station equipped with storage batteries is planned to be constructed in the near future. The modelling results revealed that using a structure varying throughout the year increases storage battery lifetime from 6 to 11 years, and there is only one (instead of three) replacement throughout the life of the batteries. The obtained results have been taken into consideration and are to be put into practice in setting up the photovoltaic system under review. The presented approach is versatile and can be used to analyze various photovoltaic systems.