Unlike most Autonomous Underwater Vehicles (AUV) which are powered by rechargeable batteries like lithium ion/ polymer and nickel metal hydride, this particular AUV is solar-powered. If you are wondering what an AUV is, then it primarily a robot which travels underwater and can operate in depths of even 6000 meters. AUV’s are also commonly known as Unmanned Underwater Vehicles. AUV is chiefly an oceanographic tool which is used by the oil and gas industry to make detailed maps of the seafloor (this is required to build under the sea infrastructure). Not just the oil industry, but the AUV is even used in military operations to identify the presence of mines on the ocean floor. But, don’t confuse them with Remotely Operated Underwater Vehicles (ROVs), which are similar to the AUV’s except that they are controlled and powered from the surface. 
Since the solar-powered AUV is not capable of working in waters deeper than 500 meters, they are very useful in monitoring lakes and rivers and analyzing their chemical makeup to check for security and environmental concerns. I would say this solar-powered AUV is not only very useful and eco-friendly, but unlike a traditional battery run AUV it is wallet-friendly too because of its low maintenance costs. Source
