The cooling system relied on an 8-hour battery supply, which are reportedly being supplemented by other similar batteries being airlifted by military aircraft if operators are unable to get the diesel generators or grid power back up in time.

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This is what happened at Fukushima the cooling system failure after the tsunami caused the system to switch to battery power.

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In extremely high external temperatures, the cooling circuit for the battery can be additionally boosted with the aid of the air conditioning system.

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