Tepco Falls on Risk of Delay to Restart World’s Top Atomic Plant

(Bloomberg) -- Tokyo Electric Power Co. slumped the most in almost five months after the utility said it would delay upgrades at reactors, risking to push back plans to restart the world’s biggest nuclear power plant.

The company will postpone until August 2029 construction of anti-terrorism equipment at its Kashiwazaki Kariwa power plant that’s required to restart the Unit 7 reactor. Tepco had previously planned to finish the project by next month.

The shares slumped as much as 5.6% to 371 yen ($2.49), the biggest intraday decline since Sept. 30. Post-Fukushima safety guidelines require operators to construct separate buildings that include backup power and water pumps for reactors in the event of a terrorist attack, such as being hit by a hijacked airplane.

Tepco, the utility that powers Japan’s capital, installed fuel in the reactor last year and has said it could be ready to produce power within a month of receiving final approval from the local government in Niigata prefecture north of Tokyo. Kashiwazaki Kariwa has seven reactors, making it the biggest nuclear plant in the world, but has been fully shut since early 2012 following the disaster at Fukushima Dai-Ichi, another Tepco facility. 

Completion of safety construction for the Unit 6 reactor at the facility was postponed to September 2031 from September 2026, Tepco also said. The dates were pushed back due in part to a shortage of construction workers, NHK reported, citing unidentified sources.

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