[6] The management team won the 2013 National Cleantech Open Energy Generation competition and awards at the 2014 ARPA-E Future Energy Startup competition,[7] were members of the 2014 Y Combinator program,[8] and were awarded a 2015 ARPA-E ALPHA contract, "Staged Magnetic Compression of FRC Targets to Fusion Conditions".

[12] This system is intended to operate at 1 Hz, injecting plasma, compressing it to fusion conditions, expanding it, and recovering the energy to produce electricity.

An FRC is a magnetized plasma configuration notable for its closed field lines, high beta and lack of internal penetrations.

[20] Helion and MSNW published articles describing a deuterium-tritium implementation that is the easiest to achieve but generates 14 MeV neutrons.

[20] In 2014, according to the timeline on the company website, Grande, Helion's 4th fusion prototype, was developed to test high field operation.

Grande achieves magnetic field compression of 4 tesla, forms cm-scale FRCs, and reaches plasma temperatures of 5 keV.

[14] Helion detailed D-D fusion experiments producing neutrons in an October 2018 report at the United States Department of Energy's ARPA-E's annual ALPHA program meeting.

[23] In 2021, the firm announced that after a 16-month test cycle with more than 10,000 pulses, its sixth prototype, Trenta, had reached 100 million degrees C, the temperature they would run a commercial reactor at.

[28] This prototype is expected to be able to heat fusion plasma up to temperatures greater than 100 million degrees C.[29] Polaris is planned to be 25% larger than Trenta to ensure that ions do not damage the vessel walls.

[34] In November 2021, Helion received $500 million in Series E funding, with an additional $1.7 billion of commitments tied to specific milestones.

He noted that the company is one of several that has continually claimed "power in 5 to 10 years, but almost all have apparently never produced a single D-D fusion reaction".

The report stated that the primary challenge with Helion's approach is "whether they can simultaneously achieve sufficiently high compression while maintaining plasma stability".