P2P-Ironing is dedicated to advancing sustainable cold-ironing solutions in line with European directives and international regulations, thereby promoting the decarbonization of the shipping industry. Our project focuses on designing, developing, and evaluating a Peer-to-Peer (P2P) Transactive Energy System (TES) that leverages blockchain technology to create an automated energy trading market among Energy Producers, Aggregators, and Consumers (Ships). This innovative market aims to balance energy supply and demand, reduce electricity costs for ships and operators, and facilitate the integration of alternative green technologies, such as compressed biomethane—a solution currently under development for cold ironing in Cyprus. Given the lack of a specified operational model for cold ironing, our project activities will define the roles and responsibilities of all involved actors, aligning them with the market entities considered. While blockchain-based TES have been widely adopted across various applications, their implementation in the cold-ironing process is unprecedented, making our project unique both nationally and internationally.