Wind, water, earth, and fire are the 4 elements that interact harmoniously. So they're a major derivative of renewable energy. Along with every wave and water current, there's a source of energy waiting for exploration. Japanese engineers have decided to leverage the opportunity by constructing a tidal machine that utilizes the current into an extensive electricity supply.

For over a decade, a Japanese company, Ishikawajima-Harima Heavy Industries (IHI), commenced operation in the project. Along the line, the company made a partnership with New Energy and Industrial Technology Development Organization (NEDO) in 2017 to merge resources and fast-track the prototype design process. Japan, having the world's 6th-largest territorial waters and economic border needs to utilize the ocean’s renewable energy. Early in the year, the project passed a testing phase in the deep waters off Japan's southern coast. The test could prepare it to begin major operations.

The prototype weighs 330 tons and goes with the name ‘Kairyu.’ The word is transcribed into “ocean current.” It consists of a 20 meters long fuselage suspended by a pair of identical-sized cylinders. Each cylinder houses a power system attached to a slender turbine blade. When suspended in the ocean, Kairyu identifies and positions itself to find the most efficient and appropriate stance to generate power from a water current. It channels the current into a grid.

The machine can float to the epicenter of the current. In terms of maintenance, the turbine can float to the water surface for easy access. Generating power from the ocean is a form of ocean renewable energy. Japan is situated near Kurushio, one of the largest and most powerful water currents. If these currents are appropriately harvested, they could produce approximately 205 GW. This figure is slightly comparable to Japan’s entire power generation.

The Kairyu system would be harbored and anchored below sea level. The device is capable of producing a total of 100 kilowatts of power. Compared with a conventional wind turbine power of 3.6 megawatts, it may look like little bubbles. The system hovers approximately 50 meters below the undercurrent. When it wafts towards the ocean’s surface, it creates inertia on the turbines. The blades rotate in opposing directions which accounts for their stability in water. Currently, Japan is grossly dependent on renewable energy. The country relies on importing fossil fuels to generate a significant amount of energy. Since the aftermath of the Fukushima disaster in 2011, Japan has been motivated to harness its technological prowess to utilize renewable resources.

Limitations for Kairyu?

Sure, every device has its shortcomings but some limitations surrounding the use of Kairyu span down to the little area for wind turbines and solar panels. Due to the geographical location, it impedes the opportunity for energy trade with other countries.

The amount of the ocean’s energy makes it a challenge to use as a power source. Most of the tumultuous energy is seen on the surface. Unfortunately, the surface is a breeding ground for typhoons which easily destroy power plants.

Reference

●       sciencealert.com

●       popular mechanics.com