The ARIES team is currently completing a 3-year study of compact stellarator power plants

(posted 7 July 2007)

The ARIES Program is a national, multi-institutional research activity funded by the US Department of Energy and led by researchers from the UCSD Center for Energy Research. The mission of the ARIES program is to perform advanced integrated design studies of long-term fusion energy concepts to identify key R&D directions and to provide visions for the fusion program.

The ARIES Team is currently completing a three-year study of compact stellarators. A stellarator is a device used to confine hot plasma with magnetic fields in order to sustain a controlled nuclear fusion reaction. It was one of the first concepts conceived (by Lyman Spitzer) for magnetic confinement of plasmas; the first devices were built at the Princeton Plasma Physics Laboratory in 1951. Stellarators are distinguished from the "tokamak" configuration used by the ITER test reactor in that the magnetic fields used to confine the plasma are completely generated by external coils.

Fig. 1 Power producing core of ARIES-CS

Stellarators have many desirable features as fusion power plants: steady-state operation without externally-driven plasma current (low recirculating power) and stability against external kinks and large vertical displacement events without any feedback coils or conducting walls. A detailed and integrated study of compact stellarator configurations, ARIES-CS, was initiated in 2003 to advance our understanding of attractive compact stellarator power plants and to define key R&D areas.

Fig. 2 Unlike their predecessors, compact stellarators approach tokamaks in size and power density

Stellarators with an underlying quasi-axisymmetric magnetic field structure have attracted intense interest in recent years because of the favorable particle drift trajectories in such configurations. In particular, compact, quasi-axisymmetric devices, which combine the feature of good particle orbits of a tokamak and the potential of being able to operate with MHD stable plasmas that are resistant to disruption at high pressure afforded by the three-dimensional shaping, open a new window of opportunity for confining steady-state, high β plasmas in magnetic fusion devices. The ability to operate at a relatively low plasma aspect ratio (~4-5) is of particular importance for burning plasma devices and power plants, as they would be similar in size to tokamaks (see Fig. 2).

For more information on the ARIES-CS project, download the recently published progress report.

Additional links:

NCSX National Compact Stellarator Experiment

Other stellarator links