Nuclear fusion is the process in which light elements are combined under extreme temperatures and pressures to create heavier elements. This reaction results in a release of energy in the form of light and heat. Most commonly, Deuterium and Tritium (which are both isotopes of hydrogen) are combined at temperatures in excess of 100 million degrees Celsius to yield Helium, neutrons and most importantly large amounts of energy.

The current proposed method to achieve nuclear fusion is to heat Deuterium and Tritium to over 100 million degrees Celsius in a large donut-shaped vacuum chamber. This super-heated hydrogen-isotope plasma will be controlled using superconducting magnets surrounding the vacuum chamber. This combination of plasma control, extreme pressure and temperature provides ideal conditions for fusion of Deuterium and Tritium (D-T) to occur.   

The effort to develop a system to host sustained fusion reactions is a global one. The EAST (Experimental Advances Superconducting Tokamak) and WEST (Tungsten (chemical symbol W) Environment in Steady-state Tokamak) are two of the leading experimental reactors. However, neither of these machines produce actual net power fusion reactions. They are used to test and refine conditions that will be necessary for power producing fusion reactions. 

The WEST facility in France currently has the record for the longest sustained hydrogen plasma reaction at approximately 22 minutes which beat the earlier record set by EAST at approximately 17 minutes. This is a massive technological success, and necessary for future power producing reactors to facilitate conditions for sustained power producing Deuterium-Tritium fusion reactions.
The National Ignition Facility (NIF) and Joint European Torus (JET) are the only facilities to have achieved actual fusion reactions. This means they have successfully combined Tritium and Deuterium to produce energy.

The experiment at JET was significant as it represents the most fusion power produced.  In its final experiment before decommissioning, JET produced 69 Megajoules of energy from the D-T fusion over a 5 second pulse.  Only .21 milligrams of fuel was used to yield this amount of energy. For comparison, 2 kilograms would need to be burned to achieve an equal yield.  This means that nuclear fusion is approximately 10 million times more efficient by mass of fuel consumed.   

Despite clear momentum and breakthroughs, much still has to be done to have fusion powering homes across the country and world.  Firstly, there needs to be an increase in investment. Fusion is still decades away from implementation which drives short-term investors away. Government funded research and institutions such as Lawrence Livermore and other DOE labs are crucial to get fusion to a point where it is a valuable investment for private investors.  This prerequisite opens the door for more research and development of not only the physics and materials surrounding making fusion reliable, but also the systems engineering that will be able to convert the energy yielded in a fusion plant and be able to connect it to the grid.   

Looking to the future, using the data and lessons learned from the research done at facilities such as WEST, EAST, NIF, JET and other international partners, there are new fusion plants being built. Foremost among them is the ITER plant in France. Contrary to current Tokamak machines, ITER will fuse Deuterium and Tritium with the goal of being the first power producing fusion plant. The tokamak is currently under construction, and the first plasma experiment is slated to happen in 2034. Despite many remaining challenges related to scalability, consistency, and controllability, the future of fusion is bright, and the next 20 years should reveal the fruits of the scientific communities’ labors as new facilities get online.