Japan has successfully tested a system that could provide a constant, steady form of renewable energy, regardless of the wind or the sun. For more than a decade, Japanese heavy machinery maker IHI Corp. has been developing a subsea turbine that harnesses the energy in deep ocean currents and converts it into a steady and reliable source of electricity. The giant machine resembles an airplane, with two counter-rotating turbine fans in place of jets, and a central ‘fuselage’ housing a buoyancy adjustment system. Called Kairyu, the 330-tonne prototype is designed to be anchored to the sea floor at a depth of 30–50 metres (100–160 feet). Source: https://www.business-standard.com/