[hobscoop]

SPARC is very important, but it's a physics demonstration facility, not a reactor. Its not going to generate any electricity. CFS (SPARC's parent company) will use SPARC to demonstrate that their magnet technology and plasma physics can be scaled to a reactor -- I think they're aiming for 2030 or 2035 to 'put electrons on the grid' with their 'ARC' reactor. SPARC stands for 'smallest possible ARC'.

Compared to CFS's approach, Helion's approach is different in two or three key ways.

First, it's a different fusion reaction, which has important engineering consequences. The reaction that Helion wants to use generates fewer damaging neutrons, which makes the rest of the reactor easier to engineer and eliminates several tricky subsystems.

Second, it's a different geometry, which does not require huge powerful steady-state superconducting magnets. However, it does require very fast magnets. It's a pulsed machine (they would fire several shots per second; each shot lasts on the order a milliseconds if I recall). So it requires more pulsed power systems and the components may need a different kind of high-repetition lifecycle testing.

Third, they want to use a 'direct energy conversion' scheme, which means eliminating the need for gas turbines (i.e. steam turbines) coupled to generators. This is important since the heat exchangers and turbines make up very roughly half the cost of a traditional power plant, so this would allow the electricity price to be lower by about a factor of two!