E. Nasr S. Wimbush P Noonan P. Harris R. Gowland & A. Petrov
Spherical Tokamak for Energy Production (STEP) requires high-field magnet designs and has therefore adopted REBCO-based high temperature superconductor (HTS). HTS enables the Toroidal Field (TF) coils to be re-mountable, which unlocks STEP’s vertical maintenance approach, however, re-mountable joints, approximately 18 GJ of stored energy, and lim…
PreprintD. Kennedy M. Giacomin B. Patel C. M. Roach D. Dickinson
The importance of parallel magnetic field perturbations in gyrokinetic simulations of electromagnetic instabilities and turbulence at mid-radius in the burning plasma phase of the conceptual high-β, reactor-scale, tight-aspect-ratio tokamak STEP is discussed. Previous studies have revealed the presence of unstable hybrid kinetic ballooning modes (…
PreprintA. Fil L. Henden S. Newton T. Hender M. Hoppe
Generation of Runaway Electrons during plasma disruptions, and their potential impact on the plasma facing components, is of great concern for ITER and future reactors based on the tokamak concept. The STEP (Spherical Tokamak for Energy Production) programme aims at producing net energy from a prototype fusion energy plant. At its current design po…
PreprintJonathan Keep Chris Harrington Steven Killingbeck Stuart Muldrew Chris Waldon
The STEP design space is an intimidating and hostile arena to operate with extensive uncertainties in the pathway heightened by many moving parts, causality breakdown, and multiple significant decisions to be made. Many strongly interacting elements (tensions) of the requirements/constraints and the design within the physics, technology and enginee…
PreprintJames Roberts Ross MacDonald Alex Russell James Redman Ian Bunce Terry O’Sullivan Ethan Flynn
In future demonstration fusion power plants, plasma facing components will face high steady state and ultra-high transient heat loads from the plasma. Introducing low thermal conductivity features to the component can reduce the peak temperatures seen by the coolant pipe, but at the trade-off of a loss of steady-state performance. Producing low-…
PreprintJ. Foster H. Lux
Estimating costs of prototype or demonstration fusion power plants is difficult enough due to the often still preliminary designs combined with a non-existing supply chain for many bespoke technologies or materials. Extrapolating to commercial fusion power plants without a clear design is even harder and uncertainties are large. As a result, for…
PurchaseA. Quadling D. Bowden C. Hardie A. Vasanthakumaran
The STEP environment will include magnetic, thermal, mechanical and environmental loads far greater than those seen in the Joint European Torus campaigns of the past decade or currently contemplated for ITER. Greater still are the neutron peak dose rates of 10-6displacements per atom, per second, which in-vessel materials in STEP are …
PreprintH Meyer the STEP Team
The programme to design plasma scenarios for the Spherical Tokamak for Energy Production (STEP), a reactor concept aiming at net electricity production, seeks to exploit the inherent advantages of the spherical tokamak (ST) while making conservative assumptions about plasma performance. This approach is motivated by the large gap between present-da…
PreprintNousheen Nawal Hanni Lux Member IEEE Rhian Chapman James R. Cowan Member APM
Being a novel technology, estimating costs for fusion power plants comes with large uncertainties. Cost uncertainties in prototypes arise from various sources and reduce with programme maturity (including the selection of a site), technical and design maturity, maturity of the commercial strategy (e.g., make vs. buy decisions, partnering de…
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