Construction of the first phase of the world's first commercial underwater data center (UDC) is nearly complete, with a sealed watertight cabin placed on the seabed off the shores of Lingshui Li Autonomous County in south China's Hainan Province on Friday. The cabin, which weighs 1,300 tonnes, not only serves as a data repository but also operates as a supercomputer. It can process over four million high-definition photos in mere 30 seconds, a workload equivalent to about 60,000 traditional computers. The UDC uses seawater as a natural cooling source, thus increasing the overall energy efficiency by 40 to 60 percent.