MODULAR STELLARATOR REACTORS AND PLANS FOR WENDELSTEIN 7-X

Modular stellarator reactors of the Advanced Stellarator type appear to have the potential to offer desirable reactor properties: i) a single NbTi coil system is sufficient; ii) steady-state operation is inherent and rests upon refuelling and exhaust only (no current drive system is needed); iii) there is no possibility for a major current disruption because there is no net toroidal current; iv) reactor volume, mass and magnetic field energy are comparable to those of tokamak reactors. The Wendelstein 7-X experiment will provide an integrated concept test which is needed for producing convincing predictions on the properties of this reactor approach.