On March 18 at 11:50 p.m., NHK News Web reported that there was a power blackout at Fukushima Daiichi Nuclear Power Station and subsequent suspensions of the cooling system of reactors Unit 1, 3 and 4. According to Tokyo Electric Power Company (TEPCO), part of the power supply to reactors stopped at 7 p.m.. Reactor Unit 1, 3 and 4 contains 2100 spent fuel rods. The pool water temperature will increase by around 0.1 to 0.3 degrees per hour. At the moment, the reactor with the highest water temperature of all the reactors is Unit 4 which measures 25 degrees.
In addition, the cooling system of the spent fuel pool placed by the nuclear reactors which contains 6300 spent fuel rods is also suspended.
NHK News Web 18/03/2013 at 23:50 (Japan)
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