Environmental impact offset 1.4 months
Batteries are becoming a relevant and cost effective means of reducing emissions of both greenhouse gases and NOx from the maritime industry. However, not much has been said about the environmental impact of the material extraction, production, and transportation of the batteries. With COP23 talks in progress this presents a great opportunity to explore the full emissions picture of batteries in hybrid and electric ships.
Recently the Maritime Battery Forum in cooperation with Grenland Energy, ABB, and DNV GL for the Norwegian NOx-fund published a report on the life cycle assessment of batteries used in ships. The study was structured as a cost-benefit analysis, where the environmental costs of creating the battery system (the energy storage and power conversion) was compared to the emissions savings of using the battery, and an environmental payback time was calculated.
For a typical electric ferry, the environmental impact of producing the batteries will be offset by emission reduction in the ship within 1.4 months. If batteries are used in a typical offshore supply vessel and used as a partial replacement for a main engine, it takes 1.5 months.
The environmental repayment period is remarkably short. The result clearly shows that marine electrification is environmentally friendly, at the same time it has been shown to also be a profitable solution for ship owners. Furthermore, a DNV GL study, which modelled the entire Norwegian fleet based on AIS data, showed that even if all known energy efficiency techniques are employed in all ship types of the entire domestic fleet, it will not be possible to reduce emissions from domestic shipping by the 40% target. Alternative propulsion such as the use of fully electric vessels is necessary to achieve emission reduction goals.
You can read the full study, published in both English and Norwegian here.