3 Nuclear Fusion Research and Development
For Practical Use of Fusion Energy
DEMOReactor

Demonstrate
Fusion Power
Q=30-50
Power Generation of500-1000 MW

ITER Project: Demonstrate the Scientificand Technological Feasibilityof Fusion Energy
Construction
Site;FranceExperimental
Reactor

Broader Approach:
Develop Technological Basisfor DEMO with supporting andcomplementing ITER

Achievement ofFusion Burn with Q≧10for 300-500 seconds

Hosted by Japan

Q: Energy Multiplication Factor

Contribution as a Semi-Host Country (20% of Equipments and Staff)

AOMORI

International Fusion Energy
Research Center

Fulfillment of ITER Large R&D
Projects:
Development of CentralSolenoid Model Coil,
Vacuum Vessel, etc.

IBARAKI

World Highest Energy Multiplication
Factor: 1.25
World Highest Temperature:
520 million K

Fusion Engineering:
Material, Blanket, etc.

Engineering Validation andEngineering Design Activities forIFMIF
Hosting international design teamBlanketFusion Plasma:JT-60

DEMO design and R&D coordination center
Fusion computer simulation center
ITER remote experimentation center

Satellite Tokamak
Fusion plasma research for the effective
start of ITER experiment and the DEMO

Fig.3-1 Development Steps Toward the Fusion DEMO Reactor

At the Fusion Research and Development Directorate,crucial R&D for practical use of fusion energy (fusion plasmaand fusion engineering R&D) is being carried out in wide scaleinternational cooperative projects such as ITER project andBroader Approach, aiming at realization of the fusion DEMO
reactor (Fig.3-1).
ITER (International Thermonuclear ExperimentalReactor) Project
The ITER project is an international cooperative project todemonstrate the scientific and technical feasibility of fusionenergy through construction and operation of an experimentalreactor. The participants are Japan, EU, US, Russia, China,Korea, and India. The participants account for more than halfof the world population. The experimental reactor, ITER, isbeing constructed in Cadarache in France. The ITER agreement
entered into force in October 2007, and JAEA was designatedas the domestic agency of ITER project in Japan. Topic 3-5 andTopic 3-7, “World Record Achievement in Plasma HeatingDevice” and “Demonstration of Final Installation to within
0.5mm of a 4-ton Blanket by Remote Handling” are research
results achieved in the course of preparation for ITER
equipment procurement.
Broader Approach (BA) Activity
The BA activity is a joint project by Japan and EU executingresearch supporting ITER and the research and development
for the DEMO reactor, the next step of ITER, aiming at theearly realization of fusion energy. It is being implemented inJapan during the period of ITER construction (about 10 years).
It consists of three projects; the activities of the International
Fusion Energy Research Center, the engineering validationand engineering design activities of the international fusionmaterial irradiation facility (IFMIF), and the research activities
of Satellite Tokamak (upgrade of JT-60 to a superconductingmachine). The former two is being conducted at Rokkasho
village in Aomori Prefecture, and the satellite tokamak projectat Naka city in Ibaraki Prefecture. The agreement launching
32

JAEA R&D Review 2008

BA entered into force in June 2007, and JAEA was designatedas the implementing agency of BA activity in Japan. The BA
activity includes a remote experiment of ITER, and Topic 3-3,
“Development of the Plasma Movie Database System forJT-60”, is a result which contributes to realize it.
Fusion Plasma Research
The critical requirement for the future fusion reactor isto attain a high level of economical efficiency, namely, tosustain a high fusion power in a reactor core of compact size.
It is necessary to improve the plasma pressure (temperature ×density) to accomplish that. Topic 3-1, “Establishment of LongPulse Operation for “ITER” Burning Plasmas”, experimentallydemonstrated that a high plasma pressure can be maintained
stably using JT-60. Furthermore, Topic 3-2, “Finding theIntrinsic Rotation by Plasma Pressure”, clarified the guiding
principle to achieve high plasma pressure.
Fusion Engineering Research
The fuel of fusion energy is deuterium and tritium. A large
quantity of deuterium exists in seawater. The tritium hardly
exists naturally at all, but it can be produced from lithium,which is also contained plentifully in seawater. Topic 3-8 andTopic 3-9, “Materials Necessary for Stably Supplying Fuel
Tritium to Fusion Reactors” and “Tritium Extraction Usinga Fuel Cell” yielded results which contribute to the steadyproduction of tritium.
It is necessary to heat plasma to cause the fusion reaction.
Topic 3-4 and Topic 3-6, “Achieving High Power in the JT60U RF System” and “Development of a Large Negative Ion
Source” are results which enable the plasma to be heated more
efficiently.
It is necessary to streamline the maintenance of the fusion
reactor in order to raise its operation rate and thus improve its
economic efficiency. Topic 3-10, “Torus Configuration andMaintenance Concept of Compact Fusion DEMO Reactor” is a
result which raises the operation rate of the plant by executing
regular maintenance in a short time.