Ilaria Rosella Pagliaro The University of Seville's SMART tokamak has achieved the first plasma, studying negative triangularity to improve the stability of nuclear fusion
©University of Seville
While the demand for energy grows and the hunt for sustainable and abundant sources continues, the scientific community turns more and more to nuclear fusion. Among them is the Small Aspect Ratio Tokamak (SMART), a groundbreaking achievement. The experimental device just hit a milestone by recording its first plasma, a significant feat in the world of science.
SMART was conceptualized by researchers at the Plasma Science and Fusion Technology Laboratory at the University of Seville. SMART is unique compared to standard tokamaks for testing out a new concept: negative triangularity. The configuration could redefine fusion efficiency, with novel opportunities for energy creation.
tokamak and negative triangularity: redefining the book on fusion stability
Tokamaks are doughnut devices that are designed to confine plasma at extremely high temperatures in a stable state. Plasma stability is required for controlled and extended fusion reactions. Traditionally, the tokamak plasma has positive triangularity, i.e., the outward-facing curved edge of the ‘D’-shaped plasma.
But new studies have shown that reversing this orientation to achieve negative triangularity would be a great step in reducing plasma instabilities. Perhaps the greatest challenge facing fusion reactors is posed by Edge Localized Modes (ELMs), which are instabilities that can destroy reactor walls and disrupt sustained fusion reactions.
SMART is the first small tokamak ever constructed to investigate the benefits of negative triangularity. The goal is to verify whether or not this shape can suppress ELMs, increase plasma confinement, and support longer and hotter plasma regimes—potentially over more than 180 million degrees Fahrenheit (100 million degrees Celsius). This innovation is central to a making a condition like an “artificial sun” possible.
In addition, SMART’s ability to produce plasma in a variety of configurations makes it a highly versatile machine for testing and verifying this theory. The significance of negative triangularity is not something relegated solely to theory; even the U.S. Department of Energy has described its potential to enhance plasma stability without compromising fusion performance.
If SMART proves that negative triangularity is a good plasma stabilizer, it could pave the way for cheaper and more economically sound fusion reactors, making commercial nuclear fusion a feasible reality.
Smart and the fusion2grid strategy: shaping the future of fusion energy
SMART is not an experiment but a core part of the University of Seville’s Fusion2Grid strategy. This ambitious initiative aims to make nuclear fusion an industrial-scale energy production option.
Once the first plasma has been achieved, scientists will focus on maximizing the machine’s performance, in collaboration with researchers from across the world. SMART’s compactness integrates three cutting-edge technology approaches:
- spherical tokamaks
- negative triangularity
- high-intensity magnetic fields
The objective is to design an efficient and compact fusion reactor that would have maximum efficiency at reduced expense. If SMART is able to prove the advantage of negative triangularity successfully, it could be the spark to generate a new class of affordable and competitive fusion reactors.
Global interest in the project is growing steadily. A number of research centers are following with great interest the results of the Seville team, expecting collaboration to overcome current fusion challenges. The common goal is to develop new ways to maintain plasma stability for long times and maximize advanced confinement techniques.
Nuclear fusion: the “holy grail” of clean energy
SMART’s new achievement is piquing overseas scientific attention. Nuclear fusion is the “Holy Grail” of green power for decades as it offers a limitless supply without hazardous emissions or long-lived wastes.
The greatest challenge has always been maintaining plasma stability long enough to reach the temperatures and pressures needed for fusion reactions. If SMART can demonstrate that negative triangularity actually enhances plasma stability, it could be a major milestone toward constructing commercial fusion reactors.
The largest challenge remains plasma confinement, but SMART’s revolutionary design may be a true solution. If more research and development and global collaboration occur, the device can potentially make nuclear fusion a viable and massive energy source.
SMART’s achievement is within a larger context of fusion research. Other projects, like ITER in France, and privately funded efforts are in a competitive rush to achieve steady state fusion reactions. If SMART’s design is successful, it has the potential to impact future reactor designs, leading to smaller, inexpensive reactors that can be commercially produced.
Plasma ignition for the first time ever in SMART represents a major benchmark to reaching the goal of fusion energy. Positive triangularity, which exists in the plasma and could be taking us closer toward commercial fusion, is only half the story–there are more challenges to navigate.
The Seville team will continue collaborating with global experts to create fusion science. In a more energy-thirsty world, technologies like SMART promise the true potential for a sustainable and unlimited energy future.
Source: Science Direct
