Offshore Service Gesellschaft, headquartered in Germany, has achieved a significant milestone in maritime sustainability by successfully operating the world's first offshore support vessel, Coastal Liberty, on green hydrogen. This green hydrogen-powered vessel operates in the protected marine reserve area around the Wadden Sea and the North Sea, showcasing emissions-free operations and reduced vibrations. The decision to switch to green hydrogen as the primary energy source came after receiving class approval from DNV in February 2024. The vessel features an eCap Marine containerised hydrogen-electric energy system, highlighting innovative technology in the maritime sector. The use of pressurized hydrogen fuel, fuel cells, and batteries has not only reduced emissions but also enhanced operational efficiency by providing a more direct propulsion system and immediate response in the propeller shafts. The companies involved in this project are focused on scalability, aiming to adapt the technology for larger commercial ships and longer voyages, as well as smaller inland vessels. The local and sustainable production of green hydrogen, powered by offshore wind, further underscores the commitment to environmentally friendly practices. Additionally, upcoming maritime conferences in Bergen, Norway, and Dubai, UAE, indicate a growing interest in green energy and hydrogen fuel cells within the maritime industry, showcasing a promising future for sustainable maritime operations.