Coupling Maritime Electrification with Renewable Power Systems: The Potential of Battery Vessels

Battery vessels (BVs) have been proposed to partially electrify long-distance shipping by connecting to ocean-going vessels at sea and recharging at port, ensuring frequent cycling of the battery. While previous work has examined their maritime economics, we quantify their system-wide effects in a detailed multi-regional capacity expansion model of the Australian east coast in 2050, under multi-year weather variability. BVs have two revenue streams of comparable value - powering ships at sea and temporal grid arbitrage - and can relocate between ports. Thus, they are deployed even at costs per MWh well above stationary batteries, lowering electricity system costs (-1.3%) and reducing renewable curtailment (-31%). As peaker gas generation and electricity-sector emissions are reduced (-12%), decarbonisation through partial ship electrification is reinforced by a cleaner electricity supply.