Operational and energy consumption pattern definition for the decarbonisation of small-scale fishing vessels

Understanding the operational and energy consumption profiles of fishing vessels is essential for proposing individualized decarbonisation alternatives based on historical operational data. This study analyses the operational and energy consumption patterns of various small-scale fishing vessels in the Basque fleet. Key parameters such as engine speed, vessel speed, and fuel consumption were monitored across 506 fishing trips from six different vessels throughout 2023 and 2024. The results reaffirm that each vessel has distinct energy requirements, which also vary with different fishing gears and vessel characteristics (e.g. LOA m or installed power kW). For instance, the mean duration and fuel consumption per trip for vessel V#1 were 17.4 hours and 183.7 litres when using trolling lines during the tuna fishing season, compared to 11.4 hours and 48.8 litres when using longlines to catch hake. Additionally, results differed between vessels using the same fishing gears (e.g., 9.32 hours and 65.2 litres per trip for V#3 versus 6.2 hours and 25.1 litres per trip for V#6, both using gillnets for the same target species). One potential solution for the studied vessels is the electrification or hybridisation of their propulsion systems, given their daily return to port and relatively low energy requirements compared to other fleets. After analysing historical data, the fishing trips with the highest fuel consumption were identified for each vessel and gear type. The required kWh for electric propulsion were calculated, along with the space needed for battery banks. Among the six vessels studied, V#2 (using only gillnets) and V#5 (using longlines and vertical hook and lines) showed the lowest energy requirements of 246 kWh and 263 kWh per trip, respectively, requiring 1.71 m3 and 1.83 m3 for battery banks if electric propulsion were installed. Other vessels, such as those employing trolling lines, would require too much space to cover the entire energy requirement of some trips (e.g., 13 m3 to cover the maximum demand fishing trip for vessel V#1). Following this study, once the potential candidates for electric or hybrid solutions are identified, the specific components (battery banks, electric motors, gensets, etc.) that best fit each vessel’s design and energy requirements will be determined.