Tepco uses underwater robot to probe inside damaged Fukushima nuclear reactor


Japan’s Tokyo Electric Power Company (Tepco) has deployed an underwater robot to investigate a badly damaged reactor at the Fukushima Daiichi nuclear power plant.

Named ‘the Little Sunfish’, the robot was co-developed by Toshiba and the International Research Institute for Nuclear Decommissioning.

Tepco seeks to discover the exact location and condition of melted fuel debris inside the Unit 3 reactor, reported Japan Today.

Unit 3 is one of three reactors that suffered meltdowns following an earthquake and tsunami in 2011. Extreme levels of radiation inside the reactors make it impossible for humans to enter the area to investigate.

"Tepco seeks to discover the exact location and condition of melted fuel debris inside the Unit 3 reactor."

The water levels inside Unit 3 are also higher than those of other reactors.

Equipped with lights, two cameras, and other equipment, the remotely controlled robot will capture images of the impact of the meltdown, AP reported.

Little Sunfish is about the size of a slice of bread. It will travel to the bottom of the containment vessel, where the deposits of melted fuel debris are assumed to have accumulated.

According to Tepco, the containment chamber has been inundated by highly radioactive water as deep as 20ft.


Image: Fukushima nuclear power plant before the 2011 explosion. Photo: courtesy of KEI/ Japanese Wikipedia.