The United Arab Emirates’ (UAE) first commercial nuclear reactor came up to full power in Abu Dhabi this week. Emirates Nuclear Energy Corporation (ENEC) announced on December 7th that the new reactor, Barakah unit 1, had reached 100 percent power. The reactor’s 1400 MW capacity will supply commercial electricity in early 2021, nine years after construction on the station began in July 2012.

This marks a major milestone for the plant, and for the UAE writ large as the reactor is the single largest power generator in the country. But, it won’t be the only unit of its size operating in the UAE for long.

Units 2,3, and 4, which are the same APR-1400 design as unit 1, are well on their way to joining the grid as well. Unit 2 has been completed, and units 3 and 4 are 93 and 87 percent complete respectively.  The plant’s reactors are all Korean designed APR-1400 pressurised water reactors.

New capacity is incredibly important for the UAE as the country is rapidly growing and modernizing. As massive skyscrapers rise in cities like Abu Dhabi and Dubai, demands on the nation’s electricity grid do as well. The city of Dubai is home to the world’s tallest building, the 2,723 ft Burj Khalifa as well as the world’s largest indoor ski slope, while Abu Dhabi houses some massive structures of its own including the Etihad Towers, a collection of five massive buildings.

UAE has some of the highest energy consumption per capita in the world—in part because it has developed so much so quickly—and its grid is continually adding capacity to meet the growing demand of the country’s 9.63 million people. As of 2017, it had 30 GW of installed capacity, which produced 127,000 GWh that year.

When all four units at the plant are online, Barakah will provide approximately 25 percent of the country’s electricity. The UAE is the third largest exporter of oil in the middle east, and has the sixth largest proven reserves in the world. It also has reliable access to natural gas which it presently uses for 98% of electricity generation.