DOE Launches Inertial Fusion Energy Program After Ignition Breakthrough

The Department of Energy’s Fusion Energy Sciences program announced last month it is soliciting proposals for projects dedicated to inertial fusion energy (IFE), which uses tools such as lasers to compress atomic nuclei in a fuel target until they fuse. DOE has for decades supported inertial fusion research through its nuclear weapons program, but a growing interest in funding R&D on energy generation has compounded in the wake of Lawrence Livermore National Lab’s achievement last year of “ignition,” or net energy gain, in a laser fusion experiment.

The department expects to award a total of $45 million in grants through its solicitation, creating a series of IFE “Science and Technology Innovation Hubs” that will each receive between $2 million and $4 million per year over four years. DOE leaders have cautioned that it will likely take decades to explore whether IFE can be a practical power source, and its solicitation accordingly stipulates that hub proposals focus on foundational research prioritized through a workshop it sponsored last year.

The IFE initiative is part of a larger pivot the Fusion Energy Sciences program is making to pave the way for building a pilot power plant. For instance, the program is ramping up support for private fusion ventures through a new “milestone-based” funding initiative. That effort just awarded eight grants supporting concepts for a pilot fusion plant, including two IFE concepts, with the promise of larger sums as those companies make progress. However, it is questionable how much money Congress will provide going forward given the direction of recent negotiations over federal spending.

DOE hubs mark a new push in fusion funding

The hubs funded through DOE’s new IFE grants will address several goals, such as deepening understanding of the physics of fuel targets and improving methods of manufacturing and rapidly focusing beams on them. Other goals include improving the “scalability, modularity, survivability, compactness, and cost” of lasers and other fusion drivers as well as performing experiments that validate “high-gain target designs on large-scale facilities.”

The hubs are further expected to contribute to developing an IFE workforce through internships and exchange programs. Each hub proposal may include multiple institutions but will have a lead institution that must be based in the U.S. and have “demonstrated experience” in inertial fusion methods.

DOE’s solicitation is the first in a new program called IFE Science and Technology Accelerated Research (IFE-STAR), which fulfills congressional direction first included in the DOE Research and Innovation Act of 2018 . Through the Energy Act of 2020 , Congress subsequently called for DOE to spend $25 million annually on IFE while setting an appropriations target of more than $1 billion for the Fusion Energy Sciences program as a whole. However, recent appropriations for the program have grown much more slowly, to $763 million this year. DOE has also sought to be deliberate in its funding approach to IFE, waiting for guidance from last year’s workshop before launching a grant program.

On top of congressional direction, the momentum behind DOE supporting IFE was also increased by the fact the ignition milestone had been identified by a 2013 National Academies report as the optimal point to launch a “national, coordinated, broad-based” IFE program. DOE is committing up to $10 million to IFE this fiscal year after initially only proposing $3 million , but it is planning to keep funding relatively limited going forward, requesting $15 million for fiscal year 2024 as part of a request of more than $1 billion for the Fusion Energy Sciences program as a whole.

Congress presses for fusion technology development

Authorizing the IFE program is part of a broader change of direction that Congress has outlined for the Fusion Energy Sciences program. Other elements of this push include the milestone-based program, expanding R&D efforts in materials that would be used in fusion reactors, and supporting “alternative and enabling concepts” that depart from the most prevalent, tokamak-based approaches to fusion energy generation.

Among the top backers in Congress of this change of direction is House Science Committee Ranking Member Zoe Lofgren (D-CA), whose district is close to Livermore and who has been pressing DOE to accelerate its implementation of new fusion activities.

At a recent hearing , Lofgren lauded DOE’s $1 billion request and the IFE solicitation, which Energy Secretary Jennifer Granholm announced at a Livermore event celebrating the lab’s achievement in laser fusion. “I’m just wondering whether we ought to think bigger on this in terms of R&D now that we’ve got ignition,” Lofgren remarked.

Lofgren also asked Under Secretary for Science and Innovation Geri Richmond about the alternative and enabling concepts program, which is not in DOE’s budget request, and whether Fusion Energy Sciences should be an applied R&D office similar to the department’s Office of Nuclear Energy.

“This is something I’ve been thinking an awful lot about,” Richmond replied. “And where I land right now is let’s just give it a little more thought because I don’t want to get people’s expectations so high because there’s so much fundamental work to be done.”

Energy Subcommittee Chair Brandon Williams (R-NY), who is new to Congress, also suggested fusion needs more federal funding, saying, “It appears to me that the commercial partners, the private partners, seem to have been left behind in the fusion industry and have received an inadequate amount of federal funds compared to other energy sources.”

Milestone program to complement private capital

Private investment in fusion is well outstripping federal support at the moment: totaling $4.7 billion as of 2022, according to the Fusion Industry Association . DOE’s milestone-based program is its first major foray into supporting private efforts, with its initial awards totaling $46 million spread across eight companies. One of those companies, Commonwealth Fusion Systems, has already raised more than $2 billion in venture funding to build a compact tokamak that can achieve ignition before moving on to a power-generating reactor. Another award went to a U.S. subsidiary of the British company Tokamak Energy, which, like CFS, is progressing quickly with the development of a compact tokamak design.

The other six awards were granted to less-developed fusion concepts, including ones to Xcimer Energy and Focused Energy, which are pursuing IFE designs. Two awards went to stellarator concepts, which are similar to tokamaks but employ a more complicated geometry. Another award is funding a “Z-pinch” system and the last is supporting a “compact magnetic mirror” approach.

“By funding such a diverse portfolio, our ultimate goal is for the strongest solutions to rise to the top and to help us chart a clear path forward to bring clean fusion energy to American homes and businesses,” Granholm said in announcing the awards.

DOE has requested to ramp up its annual support for private-public fusion ventures to $135 million for fiscal year 2024, largely to further support companies as they achieve new technological and programmatic milestones. However, notwithstanding congressional support for fusion energy, such increases may be less likely to materialize in the wake of the recent debt ceiling negotiation, which resulted in Republicans and Democrats agreeing to keep non-defense discretionary spending essentially flat for the next two years.