Alternative Fusion Concepts: Helion Energy

Fusion research benefits from its variety of labs and approaches. Not all of the ideas and concepts belong to EUROfusion or publicly funded research. Private companies, even far beyond European borders, are also trying to bring fusion energy to life. In this series, Fusion in Europe introduces different approaches and provides an outline indicating what is hidden behind catchyclaims designed to attract the attention of investors. This time, we introduce Helion Energy.


Name Helion Energy Inc.
Tagline The future of energy
Management Dr. David Kirtley, CEO, Dr. John Slough, Chief Science Officer, Dr. George Votroubek, Principal Scientist
Funding Mithril, Y combiner, Capricon investment group
Headquarters Redmond, WA, US: The University of Washington hosts the basic scientific research
Established 2013


Helion Inc. is a spin-off of MSNW LLC, a company that is developing space propulsion technologies, including fusion plasma thrusters based on the Helion concepts. Helion uses Magnetised Target Fusion. Their “Fusion Engine” is similar to a diesel engine with electromagnets replacing the pistons. It is based on Field Reversed Configuration (FRC), created by an initial axial magnetic field rapidly reversed by a purely toroidal Theta Pinch current, diamagnetically balancing the plasma pressure gradient. Twin plasma guns fire opposing FRCs to coalesce in a central burn chamber. Here the deuterium-helium3 plasmoid is rapidly magnetically compressed. It fuses and the expanding particle energy is directly converted to electricity by reacting on the magnetic field, pulsing at up to 10Hz.3.


FRCs have been under investigation since the 1960s but they did not achieve high performance plasmas. They have some asymmetric instabilities and the full effects of the fusion products are unknown. The plasma confinement time is about 50% of the ~1ms pulse length. Reactor efficiency thus requires an unusually high plasma density and temperature.

Directly converting the energy of all the fast ions is problematical, especially since electromagnetic radiation and fast ion losses will decrease the useful power output by approximately 30%.The fuel is also a challenge: a 70MWth reactor burns approximately three kilograms of 3He pa. Helion would need about 25kg of tritium stock (equal to the world’s civil stock today) to create just half its 3He fuel by decay. Helion’s plans to demonstrate a 50 MWe power plant in about three years from now must also cover developing the Direct Energy Conversion and plasma science, plus remote handling and a tritium plant.

But fusion research has many surprises in wait for us, and I truly hope that one day cheap, fast-track fusion power can be achieved!


Tom Todd joined the Culham Science Center in 1975 prior to a one-year secondment to the DIII-D tokamak at General Atomics. He has also served on many design reviews for European devices, including ITER, and beyond. In 2004, he became Chief Engineer at Culham and was appointed Chief Technologist in 2011. After retiring in 2014 he became a fusion consultant and an MSc course lecturer for several universities.