Fusion It is time to color outside the lines

TL;DR

This paper discusses recent advances in fusion energy, highlighting the success of laser-driven fusion at LLNL and advocating for a shift in focus from magnetic to inertial fusion and fusion breeding to better support future energy needs.

Contribution

It proposes a strategic shift in fusion research emphasis towards inertial fusion and fusion breeding to accelerate practical energy solutions.

Findings

LLNL achieved a fusion energy gain (Q) of 1.5.

Inertial fusion may offer a more viable path to energy production.

Fusion breeding could supply fuel for future thermal reactors.

Abstract

There has been some good news, and some bad news in the controlled fusion community recently. The good news is that the Lawrence Livermore National Laboratory (LLNL) has recently produced a burning plasma. It succeeded on several of its shots where ~1.5-2 megajoules from its laser (National Ignition Facility, or NIF) has generated ~ 1.3-3 megajoules of fusion products. The highest ratio of fusion energy to laser energy it achieved, defined as its Q, was 1.5 at the time of this writing. While LLNL is sponsored by nuclear stockpile stewardship, this author sees a likely path from their result to fusion for energy for the world, a path using a very different laser and a very different target configuration. The bad news is that the International Tokamak Experimental Reactor (ITER) has continued to stumble on more and more delays and cost overruns, as its capital cost has mushroomed from ~$5 billion to ~ $25B. This paper argues that the American fusion effort, for energy for the civilian economy, should switch its emphasis not only from magnetic fusion to inertial fusion but should also take much more seriously fusion breeding. Over the next few decades, the world might well be setting up more and more thermal nuclear reactors, and these might need fuel which only fusion breeders can supply. In other words, fusion should begin to color outside the lines.