Revitalization of Fukushima

We deliver the equipment for contaminated water measures and pool fuel removal with regard to the decommissioning program, which are specified in the “Mid-to-Long-Term Roadmap towards the Decommissioning of TEPCO's Fukushima Daiichi Nuclear Power Station Units 1-4 (Mid-to-Long-Term Roadmap)“ and “Mid-and-Long-Term Decommissioning Action Plan 2020“*1, to Tokyo Electric Power Company Holdings, Inc. based on the experiences and achievements accumulated as a plant manufacturer.

We are implementing the following activities for research and development on mid- and long-term issues regarding the decommissioning program specified in the “Mid-to-Long-Term Roadmap” and “Mid-and-Long-Term Decommissioning Action Plan 2020.”

We will continue to contribute to decommissioning of Fukushima Daiichi Nuclear Power Station through technological development.

*1: Tokyo Electric Power Company Holdings, Inc. is conducting decommissioning work based on the “Mid-to-Long-Term Roadmap towards the Decommissioning of TEPCO's Fukushima Daiichi Nuclear Power Station Units 1-4 (Mid-to-Long-Term Roadmap),” which was determined at the meeting of the Inter-Ministerial Council for Contaminated Water and Decommissioning Issues. In March 2020, Tokyo Electric Power Company Holdings, Inc. established the “Mid-and-Long-Term Decommissioning Action Plan 2020“ to present the main processes of the overall decommissioning work (contaminated water treatment, pool fuel removal, fuel debris removal, and waste treatment) required to achieve the goals specified in the Mid-to-Long-Term Roadmap.

Development of Remote Decontamination Equipment

In the “Development of Remote Decontamination Technology in the Reactor Building” project implemented by the Agency for Natural Resources and Energy, we developed Arounder*2, remote decontamination equipment using high-pressure water that improves the radiation-polluted environment at the incident site of Fukushima Daiichi Nuclear Power Station.

*2 Arounder:: a term coined to denote both “All-rounder” and “Around,” because the equipment supports a wide range of contamination forms and can run in and around the building.

Photo 1. Arounder, remote decontamination equipment using high-pressure water

*: This achievement is obtained from the Subsidy for Development of the Technological Foundation for Decommissioning and Safety of Nuclear Reactors for Power Generation by Ministry of Economy, Trade and Industry (METI).
*: The figures and photo are extracted from the materials on the website of Tokyo Electric Power Company Holdings, Inc.

Development of Submersible Crawling Swimming and Shape-changing Robots for inspection prior to removal of fuel to Be Used for a Survey to Remove Fuel at Fukushima Daiichi Nuclear Power Station

Hitachi and Hitachi-GE developed an underwater swimming robot and variable shape robot to be used for a survey to remove fuel at Fukushima Daiichi Nuclear Power Station. The underwater swimming robot will survey the inside of the power station building that is filled with water and can be used as equipment that surveys retained water leakage locations in the nuclear power station from underwater.
In addition, because the nuclear power station has areas with high radiation dose, openings for inserting the equipment into the targeted section must be as small as possible. However, small-sized moving equipment was unstable and had problems running. This robot has a basic shape of stable moving equipment, combining two small-sized crawlers, and can change its shape to pass through a narrow space.

Photo 2. Submersible crawling and swimming robot(left) and Shape-changing robots (right)

Participation in IRID

As a member of International Research Institute for Nuclear Decommissioning (IRID) since its establishment, we are conducting research and development and other projects regarding decommissioning and performing the following activities.

① Development of Equipment for Investigating the Inside of the Reactor Containment Vessel at Fukushima Daiichi Nuclear Power Station

Fukushima Daiichi Nuclear Power Station Units 1, 2, and 3 may have fuel debris inside the primary containment vessel (PCV). To remove it, the internal situation of the PCV must be investigated. We are developing equipment to be used for that investigation.

Photo 3. the PCV (Primary Containment Vessel) internal investigation robot "PMORPH"

*: A word coined with "PCV (Primary Containment Vessel)" and "Metamorphose"
*: This achievement is obtained from the Subsidy Project of Decommissioning and Contaminated Water Management by Ministry of Economy, Trade and Industry (METI).

Photo 4. The boat-type submersible access devices and small-type remotely operated vehicles, which investigate interiors of PCV

*: This achievement is obtained from the Subsidy Project of Decommissioning and Contaminated Water Management by Ministry of Economy, Trade and Industry (METI).

② Research on Application of the Muscle Robot with Flexible Structuring Mechanism for Remote Operation to Fuel Debris Removal

We are researching the application of the remotely operable the Muscle Robot with Flexible Structuring Mechanism that has superior radiation hardness and impact resistance to the fuel debris removal, where work in a high-dose environment is assumed.

Photos 5 and 6. the Muscle Robot with Flexible Structuring Mechanism (Assumed work: Handling of heavy objects, handing over between adjacent arms, assembly and disassembly)

*: This achievement is obtained from the Subsidy Project of Decommissioning and Contaminated Water Management by Ministry of Economy, Trade and Industry (METI).

Photo 7. the Muscle Robot with Flexible Structuring Mechanism (Assumed work: Establishment of environment for installing cameras and handling cables)Photo 8. the Muscle Robot with Flexible Structuring Mechanism (Assumed work: Assembly and disassembly)

*: This achievement is obtained from the Subsidy Project of Decommissioning and Contaminated Water Management by Ministry of Economy, Trade and Industry (METI).

Photos 9 and 10. the Muscle Robot with Flexible Structuring Mechanism (Photo 9: Assumed work: Entry into narrow spaces, lifting/lowering in conjunction with a winch, ascending/descending by clinging and lifting of long objects
Photo 10: Assumed work: Work as a replacement for humans, narrow spaces and moving while hanging)

*: This achievement is obtained from the Subsidy Project of Decommissioning and Contaminated Water Management by Ministry of Economy, Trade and Industry (METI).

Photo 11. the Muscle Robot with Flexible Structuring Mechanism (Assumed work: Cable arrangement for the other robots and work in a narrow space)

*: This achievement is obtained from the Subsidy Project of Decommissioning and Contaminated Water Management by Ministry of Economy, Trade and Industry (METI).