Journal Writing Project – Nuclear Fusion: Powering a Brighter Future

By Isaac Vick

Nuclear fusion, the process that powers the sun, has long been hailed as a promising energy source due to its potential to produce clean and abundant energy without emitting greenhouse gases or producing long-term radioactive waste. However, achieving fusion reactions that release more energy than is initially invested has proven to be an elusive goal, requiring meticulous scientific artistry, vast technological innovation, and many long hours.

In December 2022, a significant breakthrough in fusion research was achieved at Lawrence Livermore National Laboratory (LLNL) in California. Researchers successfully created fusion reactions that produced an excess of energy for the first time. This monumental breakthrough has been dubbed “ignition.” This great accomplishment, decades in the making, involved precisely coordinating 192 lasers to blast a small chamber, triggering fusion reactions that released more energy than was initially inputted.

The intricate details of this groundbreaking experiment were revealed in five peer-reviewed papers published online in February 2023. These papers highlighted the extraordinary level of finesse and precision required to optimize conditions for fusion and maximize energy output from the lasers.

Physicist Peter Norreys of the University of Oxford described likening it to conducting a world-class orchestra, where every element of the experiment had to be meticulously coordinated and precisely timed, resulting in a beautifully crafted outcome. Norreys is very excited to see what may come of this technology in the future, hoping it may become, with time, one the greatest and most important scientific breakthrough since the discovery of fire.

To achieve ignition, extreme pressures and temperatures are necessary. The lasers at LLNL’s National Ignition Facility targeted a hollow cylinder called a hohlraum, heating it to a scorching three million degrees Celsius and generating X-rays. Within this X-ray oven, a diamond capsule containing deuterium and tritium fuel underwent implosion, reaching the hot, dense conditions required for fusion.

Previous experiments had come close to ignition, but subtle adjustments were needed to push further. Researchers increased the energy of the laser pulse and thickened the capsule’s diamond shell, altering the implosion’s symmetry. However, these adjustments necessitated further refinements to ensure uniform implosion.

Physicist Annie Kritcher and her colleagues tackled this challenge by precisely altering the wavelengths of the laser beams to compensate for plasma’s disruptive effects within the hohlraum. These meticulous adjustments resulted in fusion reactions that yielded 1.5 times the input energy, marking a significant step forward in achieving ignition.

Despite these advancements, practical fusion power generation remains a distant goal. While subsequent experiments in July 2023 achieved even larger energy gains, fusion still requires massive energy inputs compared to the energy output. However, ongoing research aims to further increase laser energy and optimize fusion conditions to eventually achieve practical fusion power generation.

Additionally, the experiments uncovered a long-predicted heating effect that mimics phenomena observed in exploding stars like supernovas. This discovery could provide insights into extreme environments and phenomena beyond fusion research, such as nuclear weapons physics.

While LLNL’s National Ignition Facility is a prominent player in fusion research, other approaches, such as tokamak confinement, are also making strides. The recent record-breaking fusion energy production at the Joint European Torus highlights the global efforts to advance fusion technology and bring the dream of clean, limitless energy closer to reality.

After decades of incremental progress, scientists are finally beginning to synchronize their “atomic orchestras,” paving the way for a future powered by fusion energy. These technological advancements hope to be applied to many fields, from transportation, in cars or even spacecraft; to consumer energy, producing clean energy for the world to consume; or even electronics, making it so you may never have to charge your phone again.

Isaac Vick is a student at Spring Grove High School, and one of 13 area students participating in the Journal Writing Project, now in its 25th year.