The U.S. plasma science community has achieved a major milestone in its effort to forge a long-term consensus strategic plan, agreeing on a set of priorities that will now be shaped into formal recommendations for the Department of Energy.
U.S. plasma science researchers concluded the first phase of a major strategic planning effort last month with the publication of the “Community Plan for Fusion Energy and Discovery Plasma Sciences.” The report was assembled through a 15 month process organized by the American Physical Society’s Division of Plasma Physics, soliciting broad community input through workshops and white papers.
The Fusion Energy Sciences Advisory Committee (FESAC) will now use the report to develop formal recommendations for the Department of Energy’s Office of Fusion Energy Sciences (FES). The work will be done through a FESAC subcommittee charged with producing a 10 year strategic plan outlining investment priorities under two budgetary growth trajectories and an unconstrained scenario. The subcommittee aims to deliver the final product by the end of this year.
Modeled on successful planning processes used by DOE’s nuclear and high energy physics programs, FES hopes the two-phase exercise will help forge consensus within a community that it believes has lacked one for too long.
Plan recommends new facilities, collaboration networks
The community plan’s recommendations are divided into two main categories: “discovery” plasma science, encompassing research on fundamental plasma properties and non-energy applications of plasmas, and fusion science and technology, encompassing work related to fusion energy generation. It also identifies crosscutting opportunities such has harnessing new computing technologies and expanding public-private partnerships.
For discovery plasma science, the plan encourages DOE to support a balanced portfolio of single and multi-investigator projects at universities, national labs, and companies, and to expand collaborative networks. Pointing to the example of LaserNetUS, a recently established network of high energy laser facilities, the plan calls for upgrading its capabilities and forming analogous networks for facilities that support pulsed power and magnetized plasma experiments. It also specifically recommends building a mid-scale facility to study magnetized plasma phenomena relevant to the solar wind, which would complement recent space-based missions.
For fusion science and technology, the plan notes its goals are “broadly consistent” with the 2018 National Academies strategy for research on magnetically confined plasmas. That report called for the U.S. to remain a full partner in ITER, an international tokamak facility under construction in France, and to begin planning for a U.S.-based fusion pilot plant that would begin operating as early as the 2040s.
Like the Academies strategy, the community plan recommends the U.S. aim to construct a pilot plant. While it states a tokamak design is currently the “leading concept” for such a facility, it adds that other approaches should also be explored, such as stellarators, which like tokamaks employ magnetic confinement principles but have more exotic geometries. It notes that inertial fusion concepts also merit consideration, stating that although the tokamak and stellarator concepts are “relatively mature, and a focus of this report, neither is ready to meet the requirements for a fusion pilot plant.”
The plan also recommends the U.S. remain in the ITER collaboration, stating the project “remains the best option for accessing burning plasmas at the scale of a power plant.” It further suggests that planning should begin immediately for a new U.S. tokamak facility that would address additional physics knowledge gaps relevant to creating a compact pilot plant, with the goal of beginning operations by the end of the decade. In calling for building a new tokamak facility, the plan takes a step beyond the National Academies report, which left open the option of upgrading an existing facility.
The plan also emphasizes the importance of expanding research on relevant construction materials and recommends building a new irradiation facility to study materials degradation under conditions similar to those in a fusion plant. In addition, it encourages close partnership with private industry to “drive innovative technologies that ensure the development of a commercially competitive product.”
Community hoping to avoid past pitfalls
FESAC last attempted to produce a set of shared priorities in 2014, but the resulting strategy failed to win widespread support. That effort was completed in a much shorter timeframe during a period of more constrained budgets, impeding efforts to build consensus. It also stoked tensions within the community over the degree to which FES should be a “science” program or a “fusion energy development” program. This time, DOE emphasized that the strategy should address both fusion energy activities and “the broader FES mission to steward plasma science.”
DOE Undersecretary for Science Paul Dabbar retraced this history at a FESAC meeting last month, recounting how when he joined DOE in 2017 he was struck by the FES community’s “lack of cohesion” relative to the communities served by the department’s other science programs. He attributed that situation in part to a “zero sum game” mentality that took hold within the community as factions sought their share of scarce resources.
Noting that budgets are now markedly higher, Dabbar offered an upbeat outlook and praised the community’s efforts, saying he feels the new plan comes “as close to representing the true consensus as possible.”
Asked if FESAC could go beyond the community plan in its recommendations, Dabbar encouraged the committee to provide additional ideas as long as it maintains community consensus. He particularly welcomed ideas on options for building additional facilities in the U.S., noting recent budget increases have already enabled FES to pursue midscale facility projects that had been “on the back burner,” such as the planned upgrade to the Matter in Extreme Conditions instrument at SLAC National Accelerator Laboratory.
At the same meeting, the eight co-chairs of the community planning exercise emphasized the importance they placed on reaching a true consensus. “It’s not a majority vote,” said Lauren Garrison, a nuclear engineer at Oak Ridge National Lab. “It is widespread agreement throughout the community.”
Another co-chair, Princeton Plasma Physics Lab theorist Nate Ferraro, said they intentionally avoided conversations about cost. “We didn't want the discussion regarding scientific and technological opportunities to turn into a discussion about who has better cost estimates for their initiatives,” he remarked.
“There's consensus to pursue all of the recommendations in this report in a blue sky scenario,” Ferraro added, while noting that budget constraints could force decisions on competing priorities. As an example, he said there is a tension in the community between wanting to move quickly to develop a pilot plant versus allowing for design concept innovation to better identify commercially viable candidates before settling on a particular approach.
“Within a blue sky plan, these two things can live together. But when you start putting constraints, this tension becomes more apparent,” he said.
FESAC takes the baton
The task of fitting the community’s priorities into constrained budgets now falls to the 23 member FESAC Long Range Planning Subcommittee, chaired by UCLA plasma physicist Troy Carter. In a presentation at the FESAC meeting, Carter said the subcommittee intends to create a concise, “punchy” report that points to the community plan for supporting details.
Praising the community’s efforts to date, Carter suggested they “set the bar higher than P5” — the strategic planning process for high energy physics — by offering community members more opportunities to shape the community plan and using a more extensive peer review process. He said the subcommittee will continue to engage the community as it develops its recommendations, including through targeted solicitations for input on cost and schedule estimates.
Carter stressed that the success of the project is likely to affect how Congress treats the field. “Before this process, a problem that our community faced as we went through budget pressure was we had no consensus plan, there was nothing on the table for what we wanted to do as a community,” he said. “We heard it from congressional staff that basically if they don't know what our priorities are, it's very difficult for them to decide that for us, but they had to, and so we are changing that now.”