The United Arab Emirates has completed the initial phase of starting up the region’s first atomic power-generation plant, reaching “first criticality,” where a nuclear chain reaction sustains itself. “We are now another step closer to achieving our goal of supplying up to a quarter of our nation’s electricity needs and powering its future growth with safe, reliable, and emissions-free electricity,” Mohamed Ibrahim al-Hammadi, chief executive of the Emirates Nuclear Energy Corporation, said on Saturday. The Barakah power-generating facility is located in the Al Dhafrah area of the Abu Dhabi emirate. It is being constructed by South Korea’s Korea Electric Power Corporation (KEPCO). The UAE’s nuclear regulator licensed the plant for operation in February. The original plans envisioned it going online in 2017, but development was beset by repeated delays. Another three reactors are slated for Barakah, which will have an eventual electrical output of 5,600 megawatts.