Tokyo Electric Power Co.’s crippled reactors in Fukushima are in a state “equivalent to cold shutdown” even though the definition would be different in the case of an undamaged plant, Goshi Hosono, the minister in charge of responding to the disaster, said today.
“We understand that there is a difference between the cold shutdown state for a normal nuclear reactor and the state of cold shutdown that we have achieved at Fukushima Dai-Ichi,” Hosono told reporters in Tokyo. “The goal is to have nuclear fuel where it is kept in a cold state and to ensure that radioactive materials are not emitted. That is the whole point of the cooling system that we have in place.”
The government on Dec. 16 announced Tokyo Electric had achieved the milestone, which has been disputed because some scientists have argued that cold shutdown doesn’t apply to melted reactors.
Cold shutdown describes a reactor’s cooling system operating at atmospheric pressure and below 93 degrees Celsius (200 degrees Fahrenheit), according to the U.S. Nuclear Regulatory Commission. Tokyo Electric has released data showing it meets these criteria at Fukushima, Hosono said.