1. Fusion Research Infrastructure
This chapter examines Spain's fusion research infrastructure, which constitutes the country's plasma physics ecosystem. The analysis draws upon the network graph of 6 entities and 5 relationships, focusing on CIEMAT's TJ-II stellarator program and the supporting role of the Instituto de Fusion Nuclear at the Universidad Politecnica de Madrid.
Spain's fusion research infrastructure is notable for its focus on the stellarator configuration — an alternative to the tokamak that offers inherent steady-state operation advantages. The TJ-II flexible heliac stellarator at CIEMAT represents Spain's primary contribution to the global fusion research portfolio and provides unique data on three-dimensional magnetic confinement physics.
1.1 CIEMAT: The National Energy Research Center
CIEMAT (Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, est. 1951 as JEN, reorganized as CIEMAT in 1986) is Spain's national energy and environmental research center, operating under the Ministry of Science and Innovation. CIEMAT's research portfolio encompasses nuclear energy, renewable energy, environmental science, and fusion research, with the fusion program centered on the TJ-II stellarator at the CIEMAT Madrid campus.
Key relationships:
- Operates the TJ-II stellarator (since 1997)
- Participates in EUROfusion Spain framework
- Collaborates with IFN-GV on fusion research
CIEMAT's fusion research division is one of the center's flagship programs, with a staff of approximately 100 researchers, engineers, and technicians dedicated to plasma physics, stellarator operation, and fusion technology development. The center's fusion activities are funded through a combination of Spanish national budgets and EUROfusion program allocations, with additional support from European Regional Development Funds.
Beyond fusion, CIEMAT conducts research in nuclear safety, radiation protection, environmental impact assessment, and renewable energy technologies. The center's nuclear expertise provides a foundation for its fusion research program, particularly in areas such as radiation shielding, materials testing, and safety analysis.
1.2 TJ-II: The Flexible Heliac Stellarator
TJ-II (operational since 1997) is a flexible heliac stellarator designed and built at CIEMAT. The device is a medium-scale stellarator with major radius R = 1.5 m, minor radius a = 0.22 m, and magnetic field B = 1 T. The "flexible heliac" configuration allows variation of key plasma parameters — including rotational transform, magnetic well depth, and shear — enabling systematic studies of how magnetic configuration affects plasma confinement and stability.
Key relationships:
- Operated by CIEMAT (since 1997)
- Contributes to EUROfusion Spain research program
TJ-II's research program focuses on several key areas relevant to stellarator physics and, more broadly, to three-dimensional magnetic confinement:
- Transport studies: TJ-II investigates neoclassical and anomalous transport in 3D magnetic configurations, providing data on how magnetic field geometry affects particle and energy confinement.
- Plasma stability: The device studies MHD stability limits in stellarator configurations, including resistive interchange modes and Alfvén eigenmodes.
- Turbulence and zonal flows: TJ-II has made significant contributions to understanding plasma turbulence and the role of zonal flows in regulating transport, with implications for both stellarator and tokamak physics.
- Plasma-wall interaction: The device studies impurity transport and plasma-wall interaction in stellarator configurations, relevant to first-wall and divertor design for future stellarator reactors.
- Configuration flexibility: The heliac design allows systematic variation of magnetic configuration parameters, enabling controlled experiments that isolate the effects of individual configuration variables on plasma behavior.
TJ-II is one of approximately a dozen operating stellarators worldwide and is the primary stellarator facility in southern Europe. Its flexible heliac design distinguishes it from other stellarators such as the Wendelstein 7-X (Germany, optimized stellarator) and the Large Helical Device (Japan, heliotron). TJ-II's contributions to stellarator physics are scientifically significant but modest in scale compared to these larger devices.
1.3 IFN-GV: Instituto de Fusion Nuclear
IFN-GV (Instituto de Fusion Nuclear, Universidad Politecnica de Madrid / Grupo de Vision) is an academic fusion research group that supports CIEMAT's stellarator program through theoretical and computational research. The IFN conducts research on plasma transport modeling, stellarator optimization, and fusion reactor systems analysis, providing theoretical support for TJ-II experimental campaigns and contributing to broader stellarator physics understanding.
Key relationships:
- Collaborates with CIEMAT on TJ-II research
- Participates in EUROfusion Spain academic activities
The IFN's research is primarily computational and theoretical, focusing on neoclassical transport calculations, Monte Carlo simulations of particle orbits in 3D magnetic fields, and systems studies of stellarator reactor concepts. The group also contributes to fusion education through graduate programs at the Universidad Politecnica de Madrid, training the next generation of Spanish fusion researchers.
1.4 Strategic Context
Spain's fusion research program operates within the European fusion research framework, with CIEMAT serving as the national coordinator for EUROfusion activities. Spain's fusion research budget, while smaller than those of Germany, France, and Italy, supports a focused and scientifically productive stellarator research program. The TJ-II device provides unique data on flexible heliac configurations that complement the research conducted on other European stellarators and tokamaks.
Spain's fusion research is notable for its concentration on a single device type (stellarator) at a single primary facility (CIEMAT). Unlike countries with dual-track programs spanning multiple confinement concepts, Spain has chosen to focus its resources on stellarator physics — a strategy that provides depth in a specific area but limits the breadth of the country's fusion research portfolio.
In the broader context of the 90-round research investigation that informs this paper series, Spain represents a modest civilian fusion research node. The country's TJ-II stellarator contributes to the global fusion knowledge base, but there is no evidence of any weapons application of this research. Spain's fusion program is fully integrated into the European civilian research framework and operates under IAEA transparency.