The UAE’s first nuclear power plant – currently under construction – is now more than 91 per cent complete, the Emirates Nuclear Energy Corporation (ENEC) announced on Sunday.

Testing remains underway at the $24.4bn Barakah nuclear energy plant in Abu Dhabi, which has four units.

ENEC revealed that the it has successfully completed the crucial Cold Hydrostatic Testing (CHT) at Unit 3 after incorporating the lessons learned from Units 1 and 2.

Prior to starting the test, Unit 3’s nuclear steam supply systems were flushed with demineralised water, and the reactor pressure vessel head and reactor coolant pump seals were installed, a statement said.

During the CHT, the welds, joints, pipes and components of the reactor coolant system and associated high-pressure systems were verified.

The pressure inside Unit 3’s systems was also increased to 25 per cent above what will be the normal operating pressure to test the quality of the Unit’s construction.

Throughout the testing process, inspection teams from Korea Hydro and Nuclear Power (KHNP), the Korea Electric Power Corporation (KEPCO), along with ENEC and Nawah Energy Company (Nawah) performed detailed system inspections, verifying no component and piping system leakage, the statement added.

“The successful completion of the CHT ensures that Unit 3’s coolant systems and high-pressure components meet the highest international standards of quality and safety, as per the regulations of the Federal Authority for Nuclear Regulation,” said Mohamed Al Hammadi, CEO of ENEC.

“The completion of these tests approximately one year after the completion of the same testing on Unit 2 demonstrates the experience we have gained from building four identical Units at the same time.

“Step by step we are moving closer to achieving our goal of supplying the UAE with clean and reliable electricity to power its future growth and development,” he added.

The world’s largest nuclear project under construction, the Barakah power plant has total capacity of 5,600 megawatts (MW) of electricity and will be the first in the Arab world.

The plant was originally scheduled to start operating in 2017 but has faced delays, and currently aims to begin operations in 2020.

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Korea Electric Power Corporation (KEPCO) is building the four reactors simultaneously.

Earlier this year, ENEC and KEPCO completed all major construction work including major concrete pouring, installation of the turbine generator, and the internal components of the Reactor Pressure Vessel (RPV) of Unit 3, which paved the way for the commencement of testing and commissioning.

As of the end of October 2018, Unit 3 is more than 86 per cent complete, while overall progress rate of Units 1 to 4 is more than 91 per cent complete.

All four units will deliver electricity to the UAE grid, and expect to prevent the release of more than 21 million tonnes of greenhouse gas emission every year.