Nuclear fusion is a reaction in which two or more atomic nuclei, usually deuterium and tritium, combine to form one or more different atomic nuclei and subatomic particles. The difference in mass between the reactants and products is manifested as either the release or absorption of energy. This difference in mass arises due to the difference in nuclear binding energy between the atomic nuclei before and after the reaction. Nuclear fusion is the process that powers active or main-sequence stars and other high-magnitude stars, where large amounts of energy are released.
Fusion power is a proposed form of power generation that would generate electricity by using heat from nuclear fusion reactions. In a fusion process, two lighter atomic nuclei combine to form a heavier nucleus, while releasing energy. Devices designed to harness this energy are known as fusion reactors. Research into fusion reactors began in the 1940s, but as of 2024, no device has reached net power, although net positive reactions have been achieved.
Frederick Reines was an American physicist. He was awarded the 1995 Nobel Prize in Physics for his co-detection of the neutrino with Clyde Cowan in the neutrino experiment. He may be the only scientist in history "so intimately associated with the discovery of an elementary particle and the subsequent thorough investigation of its fundamental properties."
This timeline of nuclear fusion is an incomplete chronological summary of significant events in the study and use of nuclear fusion.
ITER is an international nuclear fusion research and engineering megaproject aimed at creating energy through a fusion process similar to that of the Sun. Upon completion of construction of the main reactor and first plasma, planned for late 2025, it will be the world's largest magnetic confinement plasma physics experiment and the largest experimental tokamak nuclear fusion reactor. It is being built next to the Cadarache facility in southern France. ITER will be the largest of more than 100 fusion reactors built since the 1950s, with ten times the plasma volume of any other tokamak operating today.
Aneutronic fusion is any form of fusion power in which very little of the energy released is carried by neutrons. While the lowest-threshold nuclear fusion reactions release up to 80% of their energy in the form of neutrons, aneutronic reactions release energy in the form of charged particles, typically protons or alpha particles. Successful aneutronic fusion would greatly reduce problems associated with neutron radiation such as damaging ionizing radiation, neutron activation, reactor maintenance, and requirements for biological shielding, remote handling and safety.
Magnetic confinement fusion (MCF) is an approach to generate thermonuclear fusion power that uses magnetic fields to confine fusion fuel in the form of a plasma. Magnetic confinement is one of two major branches of controlled fusion research, along with inertial confinement fusion.
A field-reversed configuration (FRC) is a type of plasma device studied as a means of producing nuclear fusion. It confines a plasma on closed magnetic field lines without a central penetration. In an FRC, the plasma has the form of a self-stable torus, similar to a smoke ring.
General Fusion is a Canadian company based in Vancouver, British Columbia, which is developing a fusion power device based on magnetized target fusion (MTF). The company was founded in 2002 by Dr. Michel Laberge. The company has more than 150 employees in three countries, with additional centers co-located with fusion research laboratories near London, and Oak Ridge, Tennessee, US.
TAE Technologies, formerly Tri Alpha Energy, is an American company based in Foothill Ranch, California developing aneutronic fusion power. The company's design relies on an advanced beam-driven field-reversed configuration (FRC), which combines features from accelerator physics and other fusion concepts in a unique fashion, and is optimized for hydrogen-boron fuel, also known as proton-boron and p-B11. It regularly publishes theoretical and experimental results in academic journals with hundreds of publications and posters at scientific conferences and in a research library hosting these articles on its website. TAE has developed five generations of original fusion platforms with a sixth currently in development. It aims to manufacture a prototype commercial fusion reactor by 2030.
Direct energy conversion (DEC) or simply direct conversion converts a charged particle's kinetic energy into a voltage. It is a scheme for power extraction from nuclear fusion.
Sir Steven Charles Cowley is a British theoretical physicist and international authority on nuclear fusion and astrophysical plasmas. He has served as director of the United States Department of Energy (DOE) Princeton Plasma Physics Laboratory (PPPL) since 1 July 2018. Previously he served as president of Corpus Christi College, Oxford, since October 2016. and head of the EURATOM / CCFE Fusion Association and chief executive officer of the United Kingdom Atomic Energy Authority (UKAEA).
Norman Rostoker was a Canadian plasma physicist known for being a pioneer in developing clean plasma-based fusion energy. He co-founded TAE Technologies in 1998 and held 27 U.S. Patents on plasma-based fusion accelerators.
Robert W. Conn was president and chief executive officer of The Kavli Foundation from 2009 to 2020, a U.S. based foundation dedicated to the advancement of basic science research and public interest in science. A physicist and engineer, Conn was also the board chair of the Science Philanthropy Alliance, an organization that aims to increase private support for basic science research, and dean emeritus of the Jacobs School of Engineering at the University of California, San Diego. In the 1970s and 1980s, Conn participated in some of the earliest studies of fusion energy as a potential source of electricity, and he served on numerous federal panels, committees, and boards advising the government on the subject. In the early 1970s, he co-founded the Fusion Technology Institute at the University of Wisconsin-Madison (UW), and in the mid-1980s he led the formation of the Institute of Plasma and Fusion Research at the University of California, Los Angeles (UCLA). As a university administrator in the 1990s and early 2000s, Conn served as dean of the school of engineering at UC San Diego as it established several engineering institutes and programs, including the California Institute for Telecommunications and Information Technology, known as Calit2, the Center for Wireless Communications, and the Whitaker Center for Biomedical Engineering. While at UC San Diego he also led the effort to establish an endowment for the school of engineering, which began with major gifts from Irwin and Joan Jacobs. Irwin M. Jacobs is the co-founder and founding CEO of Qualcomm. While Conn was dean, the engineering school was renamed in 1998 the Irwin and Joan Jacobs School of Engineering at UC San Diego. Conn's experience in the private sector includes co-founding in 1986 Plasma & Materials Technologies, Inc. (PMT), and serving as managing director of Enterprise Partners Venture Capital (EPVC) from 2002 to 2008. Over the years he has served on numerous private and public company corporate boards. Conn joined The Kavli Foundation in 2009. He helped establish the Science Philanthropy Alliance in 2012.
SPARC is a tokamak under development by Commonwealth Fusion Systems (CFS) in collaboration with the Massachusetts Institute of Technology (MIT) Plasma Science and Fusion Center (PSFC). Funding has come from Eni, Breakthrough Energy Ventures, Khosla Ventures, Temasek, Equinor, Devonshire Investors, and others.
Colliding beam fusion (CBF), or colliding beam fusion reactor (CBFR), is a class of fusion power concepts that are based on two or more intersecting beams of fusion fuel ions that are independently accelerated to fusion energies using a variety of particle accelerator designs or other means. One of the beams may be replaced by a static target, in which case the approach is termed accelerator based fusion or beam-target fusion, but the physics is the same as colliding beams.
Toshiki Tajima is a Japanese theoretical plasma physicist known for pioneering the laser wakefield acceleration technique with John M. Dawson in 1979. The technique is used to accelerate particles in a plasma and was experimentally realized in 1994, for which Tajima received several awards such as the Nishina Memorial Prize (2006), the Enrico Fermi Prize (2015), the Robert R. Wilson Prize (2019), the Hannes Alfvén Prize (2019) and the Charles Hard Townes Award (2020).
The history of nuclear fusion began early in the 20th century as an inquiry into how stars powered themselves and expanded to incorporate a broad inquiry into the nature of matter and energy, as potential applications expanded to include warfare, energy production and rocket propulsion.
Fatima Ebrahimi is an Iranian-American physicist and inventor. She carries out theoretical and computational plasma physics research for applications including fusion energy and space and astrophysical plasmas.
