Projections for a steady-state tokamak reactor based on ITER

The extensions of the physics and engineering guidelines for the ITER device needed for acceptable operating points for a steady-state tokamak power reactor are examined. Non-inductive current drive is provided in steady state by high-energy neutral-beam injection in the plasma core, lower-hybrid slow waves in the outer regions of the plasma and (30%) bootstrap current. Three different levels of extension of the ITER physics/engineering guide-lines, with differing assumptions on the possible plasma beta, elongation and aspect ratio, are considered for power-reactor applications. Plasma gain, Q/sub p/ = fusion power/input power, in excess of 20 and average neutron wall fluxes from 2.3 to 3.6 MW/m/sup 2/ are predicted in devices with major radii varying from 7.0 to 6.0 m and aspect ratios from 2.9 to 4. 3. Peak divertor heat fluxes range up to 12.2 MW/m/sup 2/ which is somewhat higher than the current ITER design limit of 10 MW/m/sup 2/ with a magnetically swept divertor. These designs were selected on the basis of improvements in physics/engineering consistent with time scales for development of future reactors. The design re-optimization on the basis of cost-of-electricity (COE) was then examined using a reactor systems model. This analysis generally verified the original estimates for the required extensions of the ITER guidelines. Cost of electricity is projected to be less than 66 mills/kW/sub e/h in all of the configurations. The smallest reactor, which has the largest neutron wall flux and mass power density, yields the lowest COE, 56 mills/kW/sub e/h. 37 refs., 8 figs., 11 tabs