Energy Management and Charging Portfolio Analysis for Future Battery Powered Harbor Vessels
Vidyasagar Tummakuri, Thanga Raj Chelliah, U. S. Ramesh
Abstract
This article intends to provide key insights to the marine designers and port authorities for adapting battery-operated zero emission electric harbor vessels (ZEE-HVs) and plan the resources for charging infrastructure. The present study is a cumulatively coordinated analysis of various significant aspects concerning the adaptation of ZEE-HVs for short-endurance commercial maritime operations. The sizing of onboard battery energy systems (OBES) is discussed for different short-endurance ZEE-HVs by considering the speed-resistance characteristics of the hull and open-water characteristics of the propeller without limiting their operations for specific load profiles/operating cycles. Charging portfolio selection is critical for a marine vessel as the OBES size is several times higher than a regular electric vehicle's battery. Hence charging portfolio selection criteria are presented to select a suitable battery charging protocol for each ZEE-HV as per the OBES ratings and available idle times on a typical day. Since the port is a commercial spot, uncertainty in resource planning leads to penalties and loss of goodwill. Therefore, Monte Carlo-based iterative analytical method is adopted to forecast the ZEE-HVs' maximum possible charging power demand on a typical day. By the load forecast data, optimal sizing of the load peak shaving battery (LPSB) was performed to limit load fluctuations at the port grid. The synergy of ZEE-HVs with LPSB and bi-directional charge-discharge controller is pivotal for effectively administering the seaport shore charging facility, which is demonstrated for a typical energy management cycle.