Executive Summary

Fusion is the merging of nuclei to release the energy that powers stars; plasmas are ionized gases, the fourth state of matter that makes up stars. The two are inextricably linked. Their shared history exemplifies how basic scientific research translates from a deeper understanding of the universe to technologies that benefit society.

Now is the time to move aggressively toward the deployment of fusion energy, which could substantially power modern society while mitigating climate change. Scientific and technological innovations enable a unique US vision for economically attractive fusion energy, with the goal of a fusion pilot plant by the 2040s. The foundation of a US fusion energy industry is central to this vision and the industry has already taken root, with approximately $2 billion of private capital invested to date.

The technological and scientific achievements arising from plasma research are significant and far-reaching. The US vision for fusion energy is enabled by breakthroughs in the physics of magnetically confined plasmas, in which record confined pressures have recently been achieved. Plasma physics helps us understand not only the confined plasmas that could power an energy-generating fusion reactor, but distant stars and other objects, such as supernovae and black hole accretion disks, that capture our imagination. Understanding the exotic states of matter created using the most intense lasers in the world requires deep knowledge of plasma physics. Plasmas transform society, enabling the development of industry-changing technologies, especially the plasma-enabled manufacturing at the heart of the trillion-dollar information technology industry.

Partnerships will accelerate progress. Partnership in the international ITER fusion project is essential for US fusion energy development, and so is supporting the continued growth of the private-sector fusion energy industry. Public-private partnerships have the potential to reduce the time required to achieve commercially viable fusion energy. The diversity of topics addressed by plasma science is reflected in the wide range of federal agencies that are committed to supporting its development. Increased coordination among those agencies is warranted to maximize progress in research and development.

Fusion and plasma research in the US are leading the world, and continued leadership requires nurturing and agility. The US is poised to take the global lead in the development of a private-sector fusion energy industry, but that opportunity will be lost without strong support. Similarly, the US leadership position in some key research areas is threatened by the absence of investment in major new facilities to address critical gaps in the relevant science and technology.

For the first time, scientists have created a long-range plan to accelerate the development of fusion energy and advance plasma science. Earlier, the community undertook a year-long study that identified new opportunities and developed guidance for prioritization. That effort resulted in the Community Planning Process report, which forms the basis for the strategy detailed here. This report calls for important redirections in the Department of Energy (DOE) Fusion Energy Sciences (FES) research programs and is embodied by six technology and science drivers in two thematic areas.

Fusion Science and Technology

The Fusion Science and Technology area should focus on establishing the scientific and technical basis for a fusion pilot plant by the 2040s:

  • Sustain a Burning Plasma. Build the science and technology required to confine and sustain a burning plasma.

  • Engineer for Extreme Conditions. Develop the materials required to withstand the extreme environment of a fusion reactor.

  • Harness Fusion Power. Engineer the technologies required to breed fusion fuel and to generate electricity in a fusion pilot plant by the 2040s.

Plasma Science and Technology

The Plasma Science and Technology area should focus on new opportunities to advance fundamental understanding and, in turn, translate these advances into applications that benefit society:

  • Understand the Plasma Universe. Plasmas permeate the universe and are the heart of the most energetic events we observe.

  • Strengthen the Foundations. Explore and discover new regimes and exotic states of matter and utilize new experimental capabilities.

  • Create Transformative Technologies. Unlock the potential of plasmas to transform society.

This plan makes the difficult choices necessary to embark on these critically important journeys. From the process, recommendations emerged that express an optimized path to achieving our goals. Overarching recommendations are made that identify important programmatic changes:

  • Addressing the technology and science drivers will require continuing investment in the design, construction, and operation of facilities that provide important new capabilities. Therefore, resources for ongoing investment need to be established in the program. Opportunities for developing small and midscale facilities aligned with the plan are also needed. Preconceptual design toward new experimental facilities should be a part of regular program activities to better prepare for future strategic planning.

  • To achieve efficiencies and maximize technical progress across all the elements of this strategic plan, it will be necessary to build on the existing successful partnerships with the National Science Foundation (NSF), ARPA-E, and the National Nuclear Security Administration (NNSA) and explore opportunities to form new partnerships with other agencies and with industry. The successful Innovation Network for Fusion Energy (INFUSE) program should be expanded and new public–private partnership programs, including milestone-based cost-share programs, should be developed.

  • This long-range planning process should be repeated regularly to enable periodic review and update of the strategic plan with strong community engagement.

  • Policy changes should be developed and implemented that improve diversity, equity, and inclusion within the research community and allow discipline-specific workforce development.

The strategic plan is developed through a series of recommendations, not in priority order, on needed programs and experimental facilities:

  • A fusion pilot plant design effort should begin immediately to develop cost-attractive fusion solutions on the fastest time scale possible.

  • The fusion pilot plant goal requires increased investment in research and development of fusion materials and other critical technology. Emphasis is needed on fusion materials science, plasma-facing components, tritium-breeding blanket technology and the tritium fuel cycle. Several key experimental facilities are recommended. The Fusion Prototypic Neutron Source (FPNS) will provide unique material irradiation capabilities, and the Material Plasma Exposure eXperiment (MPEX) and high-heat-flux testing experiments will enable solutions for the plasma-facing materials. Blanket research and the associated Blanket Component Test Facility (BCTF) will provide the scientific understanding and basis to qualify fusion power system blankets for an FPP.

  • The successful tokamak plasma confinement concept must be advanced to meet the stringent requirements of a fusion pilot plant. A sustained burning plasma at high power density is required simultaneously with a solution to the power exhaust challenge of mitigating the extreme heat fluxes to materials surrounding the plasma. US partnership in ITER provides access to a high-gain reactorscale burning fusion plasma, and an accompanying US ITER research team and program to exploit that facility must be developed. Present tokamak experiments in the US and abroad can address key issues in the near term, and new opportunities in the private sector should be leveraged and supported. Addressing the core/exhaust integration challenge requires a new tokamak facility, the EXhaust and Confinement Integration Tokamak Experiment (EXCITE).

  • The plan embraces the development of innovative ideas that could lead to more commercially attractive fusion systems and address critical gaps. The quasisymmetric stellarator is the leading US approach to developing disruption-free, low-recirculating-power fusion configurations and should be tested experimentally with a new US stellarator facility. Liquid-metal plasma-facing components have the potential to ameliorate some of the extreme challenges of the plasma-solid interface and may reveal new plasma operating regimes. Inertial fusion energy research can leverage significant investments in the US to establish new technologies and approaches to energy production. Private investment in alternative fusion plasma configurations has enabled breakthroughs that have potential as fusion energy sources. Strengthening those elements will provide both scientific opportunity and programmatic security.

  • A sequence of mid- to large-scale facilities will establish a leadership role in frontier plasma science. To strengthen plasma foundations, the Matter in Extreme Conditions Upgrade (MEC-U) will provide a world-class user facility in high-energy-density science by co-locating a high-intensity (petawatt-class) laser and a long-pulse shock compression laser with the Linac Coherent Light Source free electron laser. Additionally, a multi-petawatt laser will push the frontier of laser intensity and reveal fundamental quantum electrodynamic processes of creating matter and plasma directly from light.

    To understand the plasma universe, a new Solar Wind facility will close key science gaps in plasma turbulence, connecting laboratory experiments with space and astrophysical observations; and a mid-scale Z-pinch facility will allow access to strongly magnetized high-energy-density matter relevant to astrophysics and fusion energy research. To create transformative technologies, a high-repetitionrate high-intensity laser system will dramatically increase the rate at which high-energy-density plasma experiments can be conducted, with the potential to significantly advance the development of plasma-based accelerators.

  • A plasma-based technology research program will provide the scientific basis to enable the next generation of technological inventions. Plasmas can enable transformative technologies in manufacturing, microelectronics, biotechnology, medicine, and aerospace. Fulfilling this potential will require a dedicated, nimble research program able to take advantage of the translational nature of this research by connecting the basic science with the breadth of applications.

  • Programs that support foundational plasma science research should be emphasized. Foundational science fosters creative exploration that sets new directions for the field, addresses fundamental questions of nature, and explores novel states of matter.

Our prioritization of needed programs and facilities was applied to address three funding scenarios: constant level of effort, modest growth (2% yearly), and unconstrained but prioritized.

In the constant level of effort scenario, programs in fusion materials and technology are grown, the MPEX facility is completed, and construction of FPNS begins. Important scientific and technical progress continues in other areas. However, US leadership in fusion and plasma science is at risk in this scenario. New activities to address other key gaps are significantly delayed, and many opportunities for innovation and enhanced US leadership cannot be acted upon. To provide needed resources for fusion materials and technology programs and facilities, operations and research programs on existing domestic tokamak facilities DIII-D and NSTX-U, which aim to address fusion pilot-plant design gaps, will have to be modestly reduced in the near term. One domestic tokamak facility will likely need to cease operations mid-decade to free the resources required to make progress on FPNS. A nascent ITER research team is developed, and some shift of resources to collaboration with international and privatesector facilities is possible. A limited plasma technology program will be established. Almost all other strategically selected enhancements of experimental capabilities and new program activities will be delayed. Importantly, completing the ongoing MEC-U project is not possible under this constrained scenario as defined by the charge. New facility concept studies will be pursued to build a basis for deliberations on these important facilities.

The return on the investment of the relatively small increment from the constant level of effort to the modest growth scenario is substantial. Fusion materials and technology research is further strengthened and FPNS is accelerated. Increased focus is given to addressing the core/exhaust integration challenge, such that design and start of construction of the EXCITE facility may be possible. Fundamental plasma research and plasma technology program areas are modestly grown, and networks are established and bolstered. However, substantial risks and missed opportunities remain. A similar reduction of activity on existing tokamak programs as in the constant level of effort scenario is envisioned. Other new major facilities are not possible in this scenario, so important research gaps are unaddressed and US leadership opportunities are unfulfilled.

In the unconstrained scenario, the complete strategy as summarized above can be implemented, but prioritization and staging of items beyond the constrained scenarios is proposed. Additional investment beyond the modest growth scenario will have significant return. Major scientific advances would be enabled, and progress toward realizing practical fusion energy would be accelerated. FPNS would be further accelerated to ensure operations as soon as possible. Additional facilities and program enhancements have been identified that capture the opportunities provided by the full breadth and creativity of the program. Priority order for additional facility investment is expressed thusly: the MEC-U project and the EXCITE facility at equal priority; a new quasi-symmetric stellarator device; the blanket component test facility; the Solar Wind facility; a facility for full-size component-level high-heat-flux testing; a multi-petawatt laser facility; and, in collaboration with other agencies, the high-repetition-rate laser facility and the midscale Z-pinch could be pursued. Research programs would be bolstered first to accompany new facility investments. With careful staging of new facility construction, program pivoting, and aggressive utilization of partnerships, we believe that what is recommended in this scenario can be accomplished in a timely manner and under realistic budgets.