Fusion energy is no longer a far-off goal. It is now routinely achieved at laboratory scale but requires more energy to control the fusion reaction than the fusion reaction has released.

The path to viable fusion power from a magnetically confined plasma source requires the creation of a burning plasma, whereby the primary heating source comes from the fusion reaction itself.

To begin to consider the economic viability of a fusion power plant, the reaction must have a significant energy gain, or “Q” factor (the ratio of output power to input heating power), in a reaction that is sustained over a time frame of minutes or hours.

Construction has begun on an international experiment—the ITER tokamak—that aims to achieve a sustained reaction, and numerous privately funded smaller experiments have the potential to move forward toward this goal.

Nuclear News reached out to companies in the fusion community to ask for insights into their ongoing work. All are members of the Fusion Industry Association. Most companies submitted briefs at a specified word count, while others ran long and some ran short. Their insights appear on the following pages.

The ST25-HTS tokamak.

Governments around the world have been interested in fusion for more than 70 years. Fusion research was largely secret until 1968, when the Soviets unveiled exciting results from their tokamak (a magnetic confinement fusion device with a particular configuration that produces a toroidal plasma). The Soviets realized that tokamaks were not useful as weapons but could produce plasma in the million-degree temperature range to demonstrate Soviet scientific and technical prowess to the world.

Following this breakthrough, government laboratories around the world continued to pursue various methods of confining hot plasma to understand plasma physics under extreme conditions, getting closer and closer to the conditions necessary for fusion energy production. Tokamaks have been by far the most successful configuration. In the 1990s, the Tokamak Fusion Test Reactor at the Princeton Plasma Physics Laboratory produced 10 MW of fusion power using deuterium-tritium fusion. A few years later, the Joint European Torus (JET) in the United Kingdom increased that to 16 MW, getting close to breakeven using 24 MW of power to heat the plasma.