FuelEU Maritime necessitates a transition away from fossil fuels (European Commission EC, 2023). The available options include biofuels and RFNBO fuels, which allow ships to operate with lower carbon intensity. In addition to these options, electric vessels can be an effective technology for reducing ship emissions as FuelEU Maritime classifies electric propulsion as a zero-emission technology (EC, 2023). However, the emissions produced in the electricity generation process must be considered, meaning that the environmental impact of electricity produced in different countries can significantly affect the overall outcome. The main challenge for electric vessels is onboard energy storage. The absolute amount of energy required by vessels is large, and it must be stored in batteries for the entire voyage. Battery capacity, investment costs, and the space available onboard impose significant practical limitations. However, on short routes electric vessels can be a realistic option. The route between Helsinki and Tallinn is busy, with RoPax ferries operating almost continuous daily traffic. Crossing the Gulf of Finland takes about two hours and covers approximately 43 nautical miles. In the summer of 2025, one of the shipowners operating in the area issued a press release outlining plans to invest in a fully electric RoPax vessel for this route (Viking Line, 2025). Electric vessels of this scale have not yet been realized anywhere in the world. The objective of this paper is to examine the energy needs of the route and assess the potential of an electric ferry for RoPax traffic in the region. Currently, four RoPax vessels operate on the route under three different shipowners. Two of the vessels are LNG powered, while the other two operate on low-sulfur MGO. Based on the data, the average fuel consumption per nautical mile has been calculated. The vessels do not operate at night, but during the daytime, port calls are short (approximately one hour long) and traffic is continuous. This results in a high annual time spent at sea. Depending on the vessel, consumption varies between 31 and 37 MWh. Electric vessels have higher efficiency than diesel engines, but on RoPax electric vessels in particular, maintaining the ship’s accommodation also requires energy that cannot be supplied from the waste heat of exhaust gases. However, the chosen technical solutions determine how this energy demand is met. Depending on the ship concept (e.g., the efficiency of engines and batteries, installed engine systems, and other onboard energy needs), the required electric energy would approximately range between 45 and 55 MWh. In Finland, CO2 emissions from electricity production are remarkably low (Fingrid, 2024), averaging only 33 g/kWh (compared with specific emissions of around 600 g/kWh for a diesel engine running on MGO). Such a substantial reduction meets the FuelEU Maritime requirements and will do so till beyond the year 2050 (EC, 2023). FuelEU Maritime allows shipowners to comply through pooling, in which the carbon intensity target is assessed across a group of vessels. A very low-emission vessel can lower the pool’s average carbon intensity, allowing older and higher-emission ships to remain in operation as long as the pool as a whole meets the regulatory limit. This promotes the adoption of the cleanest possible solutions and could potentially also provide the investing shipowner with opportunities to generate business through vessel pools.
Altarriba et al. (Mon,) studied this question.