This thesis investigates the pyrolysis of marine litter plastics to produce fuel, offering an innovative approach to managing ocean plastic waste while recovering energy. Two case studies, representing 100 kg and 1000 kg per cycle, examine the scalability of this waste-to-fuel process. The mass balance results reveal high oil yields, comparable to other mixed plastic pyrolysis methods, with a significant portion recovered as marine gas oil (MGO) a potential alternative fuel for the shipping industry. Energy balance analysis demonstrates efficient energy recovery, with the majority of energy contained in the feedstock recoverable in the form of oil. Additionally, the gas produced during pyrolysis can supply enough energy to sustain the process, reducing external energy requirements.