Japan Is Dropping a Gargantuan Turbine Into The Ocean to Harness 'Limitless' Energy [View all]
Deep beneath the waves there's a source of power quite unlike any other. To tap into it, Japanese engineers have constructed a true leviathan, a beast capable of withstanding the strongest of ocean currents to transform its flow into a virtually limitless supply of electricity.
Ishikawajima-Harima Heavy Industries now known simply as IHI Corporation has been tinkering with the technology for over a decade now, partnering with New Energy and Industrial Technology Development Organization (NEDO) in 2017 to put their designs to the test.
In February, the project passed a major milestone with the completion of a successful three-and-a-half year field test in the waters off Japan's southwestern coast.

https://www.sciencealert.com/japan-s-dropping-a-kaiju-sized-turbine-into-the-ocean-to-fish-for-limitless-energy
Looks like a prototype Enterprise, a body and two nacelles. I wonder if painting it the colors of the Ukrainian flag was accidental or intentional. Either way, cool beans.