Spain has introduced a groundbreaking advancement in military technology with the deployment of the S-80 Plus submarine, distinguished by its hydrogen-powered fuel cell system. Developed by Navantia, this innovative submarine operates using AIP-BEST technology, enabling it to remain submerged for an impressive 28 days without the need to resurface. Unlike traditional AIP systems, the S-80 Plus generates its own hydrogen from plant-based bioethanol, enhancing its stealth capabilities and reducing risks associated with storing compressed hydrogen. The origins of this technology trace back to Argentina, where a researcher devised a method to produce hydrogen from ethanol. Spain's acquisition and integration of this method through Abengoa have led to the creation of a highly advanced and virtually invisible submarine. By dissolving exhaust gases in seawater, the S-80 Plus minimizes its thermal and acoustic signature, marking a significant leap in naval engineering. With a strong focus on independence and innovation, Spain has transformed the S-80 Plus into a fully national product based on the Scorpène-class project. This milestone not only enhances Spain's military capabilities but also signifies a strategic repositioning in the global geopolitical landscape. The deployment of this hydrogen-powered submarine represents a notable achievement in the realm of renewable energy and naval technology, setting a new standard for military innovation.