Improving Sustainability of Hybrid Energy Systems Part I: Incorporating Battery Round-Trip Efficiency and Operational Cost Factors

Storage systems are often employed in hybrid systems alongside generation sources. In the most basic configurations, coupling generation and storage in this manner can improve combined performance. Moreover, in advanced applications, such as for microgrids, the employment of storage offers the opportunity to diversify system objectives and pursue multiple performance goals. In this paper (part I), the authors explore formulations of storage system round-trip efficiency and operational cost, along with a model that can be determined from manufacturer data sheets and used in a real-time simulation environment for evaluation of these objectives. The battery model will be used in a real-time power management study for hybrid systems where a decentralized multiagent system (MAS), developed in part II, addresses the multiobjective tradeoff optimization for a hybrid system.