These tiny drones are set to film inside the tsunami-hit Fukushima Daiichi nuclear power plant

The operating company of the tsunami-hit Fukushima Daiichi nuclear power plant has unveiled drones to help the company investigate how exactly the 2011 meltdown occurred.

The Tokyo Electric Power Company (TEPCO) says it has been training to operate the drone since July 2023.

Weighing only 185 grammes, the drones are about the size of a slice of bread.

The drones will be accompanied by a 3-metre long, snake-shaped robot which will provide the signal for the drone to send footage.

It’s designed to send a black-and-white live feed to an operation room.

The plant’s operator has previously tried sending robots inside each of the three reactors but the plan was often hindered by debris, high radiation and the inability to navigate them through the rubble.

It has now successfully showcased the manoeuvring ability of the drones at the Japan Atomic Energy Agency’s mock-up facility.

“This will be the first time for us to conduct a survey using a drone, so we will check the procedures and safety thoroughly to ensure that we conduct the survey safely,” said Shoichi Shinzawa, TEPCO's PCV probe project group manager.

A magnitude 9.0 quake and tsunami in March 2011 destroyed the plant’s power supply and cooling systems, causing three reactors to melt down.

Hundreds of tonnes of highly radioactive melted nuclear fuel remain inside the three damaged reactors, almost 13 years after the disaster.

It is hoped that the drones will be able to gather more data from parts of the reactor that were previously inaccessible following multiple meltdowns.

TEPCO says it will deploy two of the four drones first inside the No. 1 reactor's primary containment vessel at the Fukushima Daiichi power plant to see if they can dispatch the other two to go inside with five-minute intervals, the area previous probes could not reach.

“Since the drone operation time is limited, what is important is to decide first where inside we need to check and decide the flight route. We note this in our manual and map the route, from which we base our operation,” said Shinzawa.

TEPCO will focus on filming the main structural support in the vessel, called the pedestal, located directly under the reactor’s core, in the hope it will provide insights into how overheated fuel had dripped.

The operation is expected in February, according to TEPCO.

TEPCO said it will do a test trial to remove a tiny amount of melted debris in the second reactor possibly by the end of March after a nearly two-year delay.

Spent fuel removal from Unit 1 reactor’s cooling pool is set to start in 2027, after a 10-year delay. Once all the spent fuel is removed, melted debris will be taken out in 2031.

Critics say the 30 to 40-year clean-up target set by the government and TEPCO for Fukushima Daiichi is overly optimistic.

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