REFEST is focused on the most promising scalable technologies with low CAPEX, easy to deploy and suitable to be installed in a broad range of traditional fishing ships to provide hydrodynamics, electrical power management, alternative propellers, solar electricity generation and propulsion (batteries), sensoring and digitalization, hull appendages and air lubrication. REFEST aims to achieve TRL6 – procedures and technologies to secure the reduction of fuel consumption and GHG emissions up to 40% reduction compared to the original design. The solutions proposed will be designed to ready to deploy in a broad range of small fishing vessels and they are characterized by a low CAPEX and OPEX requirements to significantly reduce the payback time). Ensuring upscaling of the proposed solutions after project implementation till 2029. The main innovations are summarized as follow: i) Innovative design by the use bulbs and spray rails that allow to improve hull hydrodynamics, to minimize the water friction and reduce external and underwater noise, ii)Recyclable thermoplastic composites for maritime applications, iii) Air lubrication systems, iv) Integration of multi-functional optical fibre sensors for hull fishing ships monitoring, v) Propulsion systems based on RIM drive solutions and its hybridization with current diesel engines, vi) Battery pack optimized to be used under cold weathers and with high percentage of reusable/recyclable components, vii) BMS, EMS, and PMS to maximize the energy consumption in the vessel, viii) Cloud-based Eco-driving software and ix) Low-weight and flexible silicon PV panels. viii) Three retrofit demo traditional fishing ships in North Sea (Denmark & Norway) and Baltic Sea (Lithuania).