Investigation of the energy efficiency of fishing vessels: Case study of the fishing fleet in the Adriatic Sea

The reduction of ship emissions is one of the most important and current research topics in maritime sciences. Different technical and operational measures as well as various business strategies are being investigated to reach future decarbonization goals. Fishing vessels generally do not belong to the categories of vessels covered by the regulations of the International Maritime Organization (IMO), but their effect on humans and the environment is very important since fishing operations are mainly performed in coastal waters. Besides, fishing is considered an energy-intensive activity that produces vast amounts of greenhouse gas (GHG) emissions. Most fishing vessels are equipped with aged, low-efficiency diesel engines resulting in relatively high CO2 indices. This paper investigates the environmental impact of purse seiners and trawlers in the Adriatic Sea, based on their technical and oper-ational characteristics, and taking into account the attained benefit for society. The energy efficiency index is formulated as a tool to compare different fishing vessels from an environmental viewpoint. The technical properties of purse seiners and trawlers operating in the Adriatic Sea are analysed from the relevant databases, and, based on the recorded realistic operating profiles, their energy needs and resulting emissions are assessed. The results show that trawlers have higher emission indices than purse seiners, mainly due to rather high energy needs and lower amounts of landed fish. However, when the income is taken into account, the difference be-tween the emission indices of trawlers and purse seiners is lower.