Steady State versus Pulsed Tokamak Reactors

TL;DR

This paper compares steady state and pulsed tokamak reactors, analyzing their efficiencies, costs, and recent technological developments, and suggests pulsed reactors could be competitive with steady state ones.

Contribution

It provides a detailed comparison highlighting the potential of pulsed reactors to be competitive, considering recent advances in superconductors and reactor design.

Findings

Pulsed reactors may be more competitive than steady state reactors.

High temperature REBCO superconductors could reduce reactor size and cost.

Further detailed engineering studies are recommended.

Abstract

We have carried out a detailed analysis that compares steady state versus pulsed tokamak reactors. The motivations are as follows. Steady state current drive has turned out to be more difficult than expected - it takes too many watts to drive an Ampere, which has a negative effect on power balance and economics. This is partially compensated by the recent development of high temperature REBCO superconductors, which offers the promise of more compact, lower cost tokamak reactors, both steady state and pulsed. Of renewed interest is the reduction in size of pulsed reactors because of the possibility of higher field OH transformers for a given required pulse size. Our main conclusion is that pulsed reactors may indeed be competitive with steady state reactors and this issue should be re-examined with more detailed engineering level studies.