Storage system scheduling effects on the life of lead-acid batteries

Abstract

Storage systems are a key element to take advantage of renewable energy due to its ability to transfer energy consumption from one time period to another. With high charge/discharge ratios one can increase the short term revenue stream from a renewable energy system whereas with a low charge/discharge ratios one can increase the long term benefits. Hence, when compared against nominal charge or discharge operation, the storage system life can be increased/reduced with a low/high charge or discharge ratios. In order to quantify this fact for different storage management strategies, this work analyze the effect on the life of a lead-acid battery system of three scheduling strategies: linear programming, crisp logic and fuzzy logic. The three cases will be compared against a reference strategy which consist on solving a linear optimization problem with perfect forecast of load, energy price and renewable availability. A photovoltaic system is taken as the renewable source and historic values for eight months are used to study the trend in the life of the storage system. it can be concluded that higher storage capacity leads to higher overall benefits, however, this cannot be said for the maximum storage system power, even when considering only the costs benefits, which suggest that a proper strategy and parameter selection can be better than high power ratio.