Boat-to-Grid for Marine Leisure Drivelines: A Swedish Case Study on Evaluating Lifecycle CO ₂ -Equivalent Emissions and Profitability

Lithium-ion batteries (LIBs), particularly Nickel-Cobalt-Aluminum (NCA) variants, are widely recognized as essential for applications such as electric vehicles, renewable energy storage, and portable electronics. The superior energy density, extended lifespan, and thermal stability of NCA batteries make them a preferred choice for demanding applications, including electric marine propulsion. In this study, the performance, lifetime, environmental impact, and economic feasibility of NCA batteries in electric boats are examined. Battery degradation is analyzed under varying operational conditions, including chargedischarge cycles and power management strategies. The findings indicate that optimized charging approaches can significantly prolong battery life. Additionally, a life cycle assessment (LCA) is conducted, comparing CO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf>-equivalent emissions between NCA battery-powered boats and conventional diesel-powered vessels. The results reveal a $\mathbf{9 2. 7 \%}$ reduction in emissions for electric boats when operated in the low-carbon energy grid of Sweden. The economic analysis explores the profitability of integrating battery systems with the grid, considering dynamic electricity pricing and projected declines in battery costs. The study concludes that NCA batteries offer a sustainable and economically viable solution for maritime electrification, supporting the transition toward cleaner transportation alternatives.