Japan and the United States are teaming up to develop a submarine that would be powered by fuel cells. It would have the ability to run under water for an entire month, on just a single charge.
The submarine is said to be unmanned, 33 feet long and would be preprogrammed to complete a course. According to reports, the submarine would be used for patrolling -- it will be equipped with sonar capabilities to detect potential threats, as well as torpedoes and other weapons.
Japan's defense ministry will invest $25 million over the next five years to develop the high-performing fuel cell for the submarine. These cells will generate emission-free energy through a chemical reaction of hydrogen and oxygen -- a method commonly used in eco-friendly vehicles.