Lawrence Livermore National Laboratory (LLNL) at the National Ignition Facility (NIF) is researching the use of advanced 3D printing to mass-produce fuel capsules for fusion energy power plants. It could be a significant breakthrough in the field of fusion energy, which is considered the “Holy Grail” of clean and abundant power.
The LLNL has already achieved a major breakthrough with the ignition inertial confinement fusion (ICF) ignition experiment in 2022. However, producing fusion energy on a commercial scale presents significant challenges.
One of the biggest hurdles is the production of fuel capsules required for ICF. These capsules contain the deuterium and tritium fuel ignited by lasers.
The fuel capsules must be nearly perfectly spherical. They currently take months to manufacture. A viable fusion power plant would require nearly a million of these capsules per day. As mentioned above, these capsules must be manufactured with extreme accuracy.
The LLNL said in a press release that “The need for perfection is such that, if a NIF capsule were enlarged to the size of the Earth, an imperfection higher than the Hollywood sign in Los Angeles would be disqualifying.” To meet this challenge, LLNL has launched a research project to develop 3D-printed fuel capsules.
Tammy Ma is the lead for LLNL’s inertial fusion energy institutional initiative. She said, “Now that we have achieved and repeated fusion ignition, the LLNL is rapidly applying our decades of know-how into solving the core physics and engineering challenges that come with the monumental task of building the fusion ecosystem necessary for a laser fusion power plant.”
The project is developing the first prototype of a dual-wavelength, two-photon polymerization (DW-2PP) approach to 3D printing. This technique utilizes two different light sources to selectively print different materials. This allows the creation of complex geometries with sub-micron resolution, potentially enabling the production of fuel capsules at the scale required for a commercial fusion power plant.
Xiaoxing Xia is co-principal investigator and a staff scientist in the LLNL’s Materials Engineering Division. He said, “We are focusing on a specific type of wetted-foam capsule, in which liquid DT can be wicked into a uniform foam layer on the inside of the spherical capsule by capillary action. “The current DT ice layering process takes up to a week to complete with extreme meticulousness. It’s possible that 3D printing is the only tool for this kind of complex geometry at scale.”
The project has already shown promising results. 3D-printed targets have successfully been used in two NIF experiments in 2024. The use of 3D printing for fusion energy is still in its early stages. However, it represents a potential solution to a critical manufacturing challenge. If this new technology is successful, it could accelerate the development of fusion power plants. This could help bring the world closer to a future with clean, safe, and abundant energy.
Jeff Wisoff is principal associate director for LLNL’s NIF & Photon Science Directorate. He said, “Unlocking fusion is a strategic asset for US competitiveness. It’s imperative that we invest in fundamental science and technology to build on the historic achievement of fusion ignition.”