PROGRESS AND DIRECTIONS IN MAGNETIC FUSION ENERGY.

Abstract

A variety of magnetic confinement schemes are under investigation as candidates for the core of a fusion power reactor. Diversity has been encouraged to ensure the emergence of the optimal long-term solution. At the moment, the tokamak and tandem mirror are the mainline programs in the United States, whereas the Reversed-Field Pinch (RFP), the Elmo Bumpy Torus (EBT), the compact torus, and the stellarator comprise the major alternative concepts. Worldwide, the tokamak has enjoyed the greatest success as a plasma confinement device, overshadowing its competitors in this respect. Yet, questions of reactor viability have forced the tokamak program to seek innovations and improvements in the concept that would make the reactor embodiment more acceptable; this issue has kept open the competition among confinement approaches. Energy break-even should take place in the Tokamak Fusion Test Reactor (TFTR), now in operation at the Princeton Plasma Physics Laboratory (PPPL), during deuterium-tritium (DT) operations in 1986. The tandem mirror concept has not reached the same level of maturity as the tokamak because it is very new. However, notable success has been achieved in the few years since its inception. With the Tandem Mirror Experiment (TMX), Lawrence Livermore National Laboratory researchers have verified the theory behind the basic tandem mirror, namely the electrostatic plugging of ions at each end of the machine.