ORNL leads five public-private INFUSE projects to advance fusion technologies

ORNL is the lead partner on five research collaborations with private fusion companies in the 2024 cohort of the Innovation Network for FUSion Energy program. Credit: ORNL, U.S. Dept. of Energy

The Department of Energy's Oak Ridge National Laboratory is the lead partner on five research collaborations with private fusion companies in the 2024 cohort of the Innovation Network for FUSion Energy, or INFUSE, program. These collaborative projects are intended to resolve technical hurdles and develop enabling technologies to accelerate fusion energy research in the private sector.

The INFUSE program, established in 2019, promotes public-private research partnerships with the fusion industrial community and leverages the unique capabilities and world-class expertise of DOE's national laboratories and U.S. universities to address barriers in advancing fusion energy technology. The partner laboratories or universities are awarded between $100,000 and $500,000 for one- or two-year projects, with at least a 20% cost share required from the private company.

This year, $4.6 million in funding was awarded to 17 projects, with ORNL leading more collaborations than any other public research institution.

"ORNL's breadth of capabilities in fusion plasma science, fusion materials, enabling technology and fusion fuel cycle position us to be a strong partner to the fusion industry," said Troy Carter, director of the lab's Fusion Energy Division. "I'm thrilled to see this opportunity from the INFUSE program to work with our partners to advance the science and technology needed to enable commercial fusion energy."

Realta Fusion's Hammer fusion pilot plant concept, top, is a tandem magnetic mirror fusion energy system that confines a plasma, bottom, between strong electromagnets at each end. Credit: Realta Fusion, Inc.

ORNL's five research collaborations are:

• Development of advanced, oxidation-resistant vanadium alloys for fusion blanket applications led by Tim Graening from the Materials Science and Technology Division at ORNL, with Tokamak Energy, Inc.

Vanadium alloys are promising candidates for liquid lithium breeder blanket structures because of their compatibility with lithium and superior mechanical properties at high temperatures, but they are susceptible to oxidation and embrittlement when exposed to elements like oxygen, nitrogen and hydrogen. This project will use thermodynamic modeling to optimize the processing of vanadium alloys with different chromium content, then evaluate the microstructure, oxidation, weld strength and properties of the alloys at high temperatures. If successful, this collaboration could develop an advanced vanadium base alloy that can better resist oxidation and open new design options for breeder blankets.

• Are Magnetohydrodynamic Forces Low Enough to Enable Single Coolant Lead Lithium Blankets in Tandem Mirror Reactors? led by Paul Humrickhouse from the Fusion Energy Division, with Realta Fusion Inc.

Fusion reactors with liquid metal blankets typically require an electrical insulator to prevent issues with magnetohydrodynamic forces, or MHD, which occur when an electrically conductive fluid interacts with a magnetic field. The addition of this insulator presents manufacturing challenges due to the increased complexity. This collaboration with Realta Fusion will examine a tandem mirror fusion reactor currently under development that features a uniform magnetic field that may reduce the MHD forces and eliminate the need for an electrical insulator. ORNL researchers will use state-of-the-art 3D modeling tools for fusion blankets to evaluate the forces within this reactor design and determine whether this simplified blanket concept is viable or needs further design changes to limit excessive MHD forces.

• Developing Matter Injection Technologies for Fusion Power Applications led by Steve Meitner the Fusion Energy Division, with General Atomics

To compete with current power plant technologies, a fusion pilot plant must be able to run for months to years at a time without outages for maintenance. This requires they be constantly fueled via matter injection, where small pellets of cryogenically frozen fuel are shot at high speed into the plasma. This project will address key design issues of a fueling centrifuge developed by General Atomics that holds promise as a matter injection technology capable of operating with the reliability required for a fusion pilot plant. The collaboration will also develop the design for an industrial-scale fusion matter injection manufacturing and qualification center, which will ensure future pilot plant development will not be hindered by matter injection technology production bottlenecks.

The SPARC tokamak will demonstrate commercially-relevant net energy fusion power at a much smaller volume than other tokamaks thanks to new high temperature superconducting magnets. Credit: Commonwealth Fusion Systems

• SOLPS-derived separatrix operating space scalings for informing SPARC integrated power exhaust scenarios led by Bart Lomanowski from the Fusion Energy Division, with Commonwealth Fusion Systems, or CFS

Commonwealth Fusion is currently building the SPARC tokamak, the world's first commercially relevant net energy fusion system. The reactor components in SPARC will be subjected to extreme heat fluxes which need to be mitigated by strategically seeding impurities in the edge of the plasma. ORNL will leverage the SOLPS-ITER code, a high-fidelity edge plasma modeling tool, to investigate the impact of these impurities on plasma performance and produce computationally lightweight models for CFS to use for scenario planning and control.

ARC, the successor to SPARC, aims to be the world's first commercial fusion power plant capable of delivering hundreds of megawatts of net energy to the grid. Credit: Commonwealth Fusion Systems

• In situ Elemental Analysis of Fluoride Molten Salt Using Laser-Induced Breakdown Spectroscopy, or LIBS led by Hunter Andrews from the Radioisotope Science and Technology Division, with Commonwealth Fusion Systems

After the completion of the SPARC device, Commonwealth Fusion will develop ARC, a commercial fusion power plant, that will contain a molten salt blanket used to breed tritium fuel and transfer heat energy from the plasma. Impurities within the molten salt can significantly alter its chemistry and impact its effectiveness. To measure these impurities in situ, in real-time, and with enough sensitivity required for service on ARC, ORNL researchers are investigating the use of Laser Induced Breakdown Spectroscopy, or LIBS. LIBS uses a high-energy laser pulse to excite material into a plasma plume and analyze the emitted light to determine the elemental composition. This project will demonstrate the viability of using LIBS to accurately measure the level of metallic and nonmetallic impurities, such as chromium, iron, oxygen and hydrogen, in the molten salt while the device operates.

"The interest in INFUSE continues to grow. This round we had by far the largest number of applicants in the six years of the program, with companies applying across diverse device and technology concepts," said Arnold Lumsdaine, INFUSE program director.

The INFUSE program is sponsored by the Office of Fusion Energy Sciences within DOE's Office of Science and is managed by ORNL and Princeton Plasma Physics Laboratory.

The other projects from this year's awards can be found on the INFUSE website.

UT-Battelle manages ORNL for the Department of Energy's Office of Science, the single largest supporter of basic research in the physical sciences in the United States. The Office of Science is working to address some of the most pressing challenges of our time. For more information, please visit energy.gov/science. - Sean Simoneau