Systems cost and performance analysis for a spherical torus-based volume neutron source

A cost and performance analysis of a spherical torus-based volume neutron source (ST-VNS) is performed using the supercode systems code. An ST-VNS, proposed as a reduced-cost option for testing the nuclear technologies necessary for tokamak power reactors, will cost about 25% of the construction cost of the International Thermonuclear Experimental Reactor Engineering Design Activities (ITER-EDA) when it is operating in an initial test phase with 0.5 MW m −2 wall load. Advanced operation at 5 MW m −2 wall load is possible with surface elongation κ=3, safety factor q 95=10, confinement enhancement factor H=2.3, and Troyon beta limit β N=5%, at a direct cost of about 30% that of the ITER-EDA. There is a narrow region β N and H space which is useful for attaining high neutron wall loads.