Accelerating Low-Cost Plasma Heating and Assembly
Fusion energy holds the promise of cheap, clean power production, but up to now scientists have been unable to successfully harness fusion as a power source due to complex scientific and technological challenges and the high cost of research. ARPA-E’s ALPHA program seeks to create and demonstrate tools to aid in the development of new, lower-cost pathways to fusion power and to enable more rapid progress in fusion research and development.
Fusion has been pursued for decades because it is perhaps the ideal power source, with abundant fuel, effectively zero emissions, manageable waste, and minimal proliferation risk. However, researchers have yet to achieve a self-sustaining, controlled fusion reaction that consistently produces more energy than it consumes. Fusion is a nuclear reaction where two small atoms like hydrogen combine to form a larger atom and produce an enormous amount of energy as a byproduct. In controlled thermonuclear fusion, these reactions are facilitated by heating and confining fusion fuel in the form of a plasma, which is created when a gas absorbs enough energy to separate the electrons from the nuclei, making it susceptible to electric and magnetic fields. It requires a great deal of energy to attain the temperatures and pressures required for fusion, and confining plasmas to sustain these conditions is a monumental technical challenge. Most mainstream fusion research currently focuses on one of two approaches to confining plasmas: magnetic confinement, which uses magnetic fields and lower-than-air ion densities, and inertial confinement, which uses heating and compression and involves greater-than-solid densities. The ALPHA program aims to create additional options for fusion research by developing the tools for new, lower-cost pathways to fusion, and with a focus on intermediate densities in between these two approaches. These new intermediate density options may offer reduced size, energy, and power-density requirements for fusion reactors and enable low-cost, transformative routes to economical fusion power.
ALPHA project teams will develop and build prototype tools that demonstrate new methods of reaching fusion conditions and that build the scientific and technological basis for future reactor designs. ALPHA teams will not develop complete fusion reactors in this program, but if successful, innovations created in this program will open the field of fusion research to a broader range of approaches by a variety of institutions, both public and private, facilitating more rapid progress toward economical fusion power. Although the technical challenges for fusion are immense, the opportunity it could provide for a stable energy future is unparalleled.
Successful development of economical fusion reactors could provide a nearly limitless supply of domestic power, eliminating dependence on foreign sources of energy and limited fuel supplies.
Fusion reactors offer nearly zero emissions and produce manageable waste products. If widely adopted, they could significantly reduce or nearly eliminate carbon emissions from the power production sector.
Fusion reactors could offer abundant, reliable power and if widely adopted could result in reduced electricity costs across the country, as well as facilitate domestic manufacturing of fusion plants.