Wendelstein 7‐X: An Alternative Route to a Fusion Reactor

Abstract With the ITER tokamak magnetic confinement fusion is making the decisive step to realize a burning fusion plasma and prepare the basis for a demonstration power plant (DEMO). Despite the advantages of an intrinsically steady state magnetic field and better stability properties, the development of stellarators lags behind by about 1 1/2 device generations, because of the difficulties to realize the desired magnetic field configuration. The goal of the optimized stellarator Wendelstein 7‐X is to overcome the principal deficiencies of the stellarator concept and demonstrate its reactor capability, combining sufficiently good thermal and fast ion confinement with reactor relevant ß and collisionality under steady state conditions. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)