|Fig. 1: Fusion Engine. (Courtesy of Helion Energy)|
Fusion Energy, also known as the energy of the stars, continues to be one of the greatest challenges and promises of the 21st century. The world needs new, cleaner ways to supply our increasing energy demand, as concerns grow over climate change and declining supplies of fossil fuels. In such circumstances, a vision where power stations use fusion to generate electricity could be a reality in 2nd half of this century. Commercial nuclear fusion could change the energy landscape as we know it today, because of several important advantages: 1) no carbon emissions 2) abundant fuels 3) energy efficiency 4) no-long lived radioactive wastes, and most importantly 5) safety - the small amounts of fuel used in fusion devices mean that a large scale nuclear accident is very unlikely. 
However, this is no news to nuclear physics scientist, as fusion has been around for over half a century now. Way back in November 1952, United States was able to successfully test the Tellar-Ullam design in a staged thermonuclear bomb test codenamed operation Ivy Mike.  Today, the ITER (International Thermonuclear Experimental Reactor) - a 500 MW Tokamak being built in South France that aims to make the long awaited experimental studies of plasma physics into full-scale electricity producing power plants - continues to herald the future of fusion energy.  While intergovernmental projects such as ITER, NIF, DEMO enjoy a lot of support from several countries and have budgets often in billions of dollars, in the last couple of years, a lot of young private companies have emerged who are trying to find solutions to nuclear fusion. In this paper, I want to throw light upon some of the most exciting startups in this space and explore their prospects for the future.
This young company is optimistic that it will be able to achieve commercial fusion energy by 2019, a date that is much ahead of most other competitor's projections. Helion develops a fusion engine, inside of which two plasmas - clouds of hot ionized gas containing hydrogen isotopes hurtle toward each other. The clouds collide inside a burn chamber, merging into a single entity. An electromagnet surrounding the chamber squeezes the plasma, raising heat and pressure to conditions required for fusion and energy release, which in turn drives a turbine to produce electricity. 
Tri Alpha is working on an aneutronic form of fusion, which delivers electricity straight from the fusion process without the use of turbine. Although a secretive Californian company, Tri-Alpha, released a paper in 2010 throwing light upon their research findings and the implications for fusion research and magnetic reconnection. They write about a hot stable field reversed configuration (FRC) has been produced in a C-2 experiment by colliding and merging two high beta plasmoids performed by a dynamic version of the field-reversed theta pinch technology, and the merging process exhibited the highest poloidal flux amplification obtained a magnetic confinement system - over tenfold increase. Most of the kinetic energy is converted into thermal energy with a total temperature exceeding 0.5 keV, and the final FRC state exhibits a record FRC lifetime with flux confinement approaching newar classical values. 5 The Tri-Alpha team says it hopes to produce a working commercial reactor some time before 2020 - possibly before ITER fires up for the first time. Although it is believed they have been able to raise 90 million dollars already, we should treat these companies with a fair bit of skepticism but also laud them for their ambitious plans. 
Other notable startups include the likes of a Canadian company, General Fusion that aims to create fusion power based on magnetized target fusion, and Lawrenceville Plasma Physics (LPP) - a small New Jersey based startup that is trying to build a safe fusion energy generator using dense plasma focus (DPF) and hydrogen-boron fuel.
Projects like the ITER and the NIF in California, which have been in planning and implementation for over decades now are gigantic multi-billion dollar fusion projects that will not be delivering commercial scale energy anytime soon. However, more importantly, the pressure to keep funding these large-scale projects has dried up government investments in other alternative approaches to fusion. Even though the DOE has an innovative confinement concept solicitation, it may want those concepts to be something that supports the tokamak. As a result, public research money may not be effectively channelized to give an opportunity or support these private endeavors.
As a result, a few venture capitalists have begun to back these projects. For example, Amazon founder Jeff Bezos has invested in General Fusion, while Microsoft's Paul Allen has supported Tri-Alpha Energy. However, these investments are still capped at a few million dollars, and for smaller companies like LPP funding continues to be a concern. Due to the long time horizon of these projects and the associated risks, it is important to question whether VC funding will be able to sustain the pace of development of private commercial nuclear fusion, given that these companies might need several billions of dollars to convert the prototypes into real fusion-backed power plants. Although it is hard to tell which of the above ideas will come closer to fruition, the government should take measures to either 1) launch a public-private partnership to back these startups with manpower and capital 2) to accelerate the process of testing these technologies for approval, and 3) creating incentives for sovereign wealth funds or other institutions to further invest in these technologies, so that a commercial nuclear fusion backed power is able to catch up to other alternatives such as natural gas, and become a reality sooner rather than later.
© Yash Poddar. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
 R. W. Cohn et al., "Economic, Safety and Environmental Prospects of Fusion Reactors," Nucl. Fusion 30, 1919 (1990).
 C. Hansen, US Nuclear Weapons: The Secret History (Crown, 1988), Chapter 2.
 K. Ikeda, "ITER on the Road to Fusion Energy," Nucl. Fusion 50, 104002 (2010).
 J. Slough John, G Votroubek, and C. Pihl, "Creation of High Temperature Plasma Through Mmerging and Compression of Supersonic Field Reversed configuration Plasmoids," Nucl. Fusion 51, 053008 (2011).
 M. W. Binderbauer et al., "Dynamic Formation of a Hot Field Reversed Configuration With Improved Confinement by Supersonic Merging of Two Colliding High-Beta Toroids," Phys. Rev. Lett. 105, 045003 (2010).