Design Blueprint: A Compact Spherical Tokamak Fusion Power Plant Sized by Energy Balance and Neutron Wall Loading

Design blueprint derived from the source paper (DOI 10.5281/zenodo.24159800): This paper presents a complete, computed design study of a fusion power plant based on a spherical tokamak: a tokamak compressed to low aspect ratio, so the plasma is nearly spherical and the centre column is slender. The fuel is deuterium tritium, releasing 17.6 MeV per reaction, of which 14.1 MeV leaves with the neutron and 3.5 MeV stays with the alpha particle. Heating is by neutral-beam injection supplemented by electron cyclotron heating, and the blanket concept is helium-cooled lithium-lead blanket with silicon-carbide flow inserts. Sizing follows from a zero-dimensional energy balance evaluated in the accompanying computation: fusion power 664.4 MW, auxiliary heating 45 MW, plasma gain Q 14.76, neutron power 532.3 MW, first-wall neutron loading 4.994 MW per square metre, gross electric output 335.3 MW, recirculating power 104.7 MW and net electric output 230.6 MW. Radiated bremsstrahlung removes 11.93 MW and transport removes 306.9 MW, against alpha-particle self-heating of 132.1 MW. The plant verdict on the stated assumptions is net positive. Where a quantity depends on an assumption that experiments have not yet demonstrated at the required value, that dependence is stated numerically so that the design can be re-scored as measurements improve. This study is simulated and computed from stated assumptions; it is not a measurement, and no part of the plant has been built. SIMULATED, NOT MEASURED. Status: DESIGN BLUEPRINT — SIMULATED, NOT MEASURED — NOT BUILT. All numbers are simulated values from the source paper's computation, deposited with this blueprint as compute.py and results.json. AI-use disclosure: Dave, an AI research system, assisted with the computation and drafting under the author's direction; author of record William Alexander Aldred.