Alternative fusion devices
Economically viable energy production based on nuclear fusion in a magnetic confinement device has not been demonstrated yet. The mainstream tokamak, stellarator, spheromak and Reversed Field Pinch designs may achieve energy production by fusion in the future, but it remains to be seen whether these designs will lead to economically viable and attractive power plants, as fusion reactors based on these designs will almost certainly need to be very large.
Given this situation, there is considerable interest in developing alternative designs. Their common goal is to achieve fusion power generation at lower cost by exploiting the hypothetical improved plasma confinement properties of a different magnetic field configuration (or other design features), which would allow a reduced size of the power plant.   Currently, none of the alternative designs have achieved these potential benefits.
Alternative designs and associated companies
- Commonwealth Fusion Systems
- Levitated Dipole Experiment
- Compact Spherical Tokamak - Tokamak energy Ltd.
- Colliding beam reactor - Tri Alpha Energy
- Polywell - EMC2 company
- Magnetized target reactor - General Fusion
- Dense Plasma Focus - LPP Fusion
- Compact Fusion - Lockheed Martin (Skunkworks)
- Applied Fusion Systems
- First Light Fusion
- D. Clery, Fusion's restless pioneers, Science 345, 6195 (2014) 370
- M.M. Waldrop, Plasma physics: The fusion upstarts, Nature 511, 7510 (2014)
- MIT launches multimillion-dollar collaboration to develop fusion energy, Nature News, 9 March 2018
- L. Grossman, Inside the Quest for Fusion, Clean Energy’s Holy Grail, Time, Oct. 22, 2015
- D. Clery, Updated: Are old secrets behind Lockheed's new fusion machine?, Science, 17 October 2014
- A former Made in Chelsea star is looking to raise £200m to build nuclear fusion reactors
- The Fusion Reactor Next Door, New York Times, May 13 (2019)