Yanmar Power Technology (YPT), a subsidiary of Yanmar Holdings Co., Ltd., has introduced a game-changing hydrogen-fueled 4-stroke engine designed for coastal vessels. The project, part of the Nippon Foundation's zero-emission ship demonstration experiment, aims to revolutionize maritime propulsion with cleaner and greener technologies. This innovative engine utilizes hydrogen as fuel, ensuring zero CO2 emissions upon combustion, aligning with the growing demand for environmentally friendly maritime solutions. The development of this cutting-edge engine involves two main configurations: a pilot ignition engine that combines biofuel and hydrogen additives, and a spark ignition hydrogen-only engine. The rigorous testing process includes onshore verification tests scheduled to begin in 2024 with a 6-cylinder hydrogen engine featuring pilot ignition, followed by further verification operations in 2026 with spark ignition hydrogen-only engines. Yanmar's hydrogen engine project is part of a larger consortium, including Uyeno TransTech, Kyoto University, Fukuoka Shipbuilding, Mitsui E&S Shipbuilding, and Mirai Shipbuilding. The company has also formed a consortium with Kawasaki Heavy Industries and Japan Engine Corporation to collectively develop hydrogen-fueled marine engines, positioning Japan at the forefront of hydrogen engine technology in maritime transportation. Beyond hydrogen, Yanmar is exploring other alternative fuels for maritime sustainability, such as ammonia, methanol, biofuels, battery-electric, and even nuclear propulsion. The focus on decarbonization and green energy sources reflects a broader industry trend towards adopting sustainable practices in maritime transport. The efficiency and environmental benefits of the Yanmar hydrogen engine are paving the way for a greener future in marine mobility, alongside similar efforts by other companies like Riviera and Wärtsilä, albeit with a focus on ammonia. The experts are optimistic about the commercial potential of this groundbreaking technology, emphasizing its positive impact on the future of sustainable transportation.