[peutetre]

Helion's reactors are smaller and simpler field reversed configuration reactors. They've built multiple prototypes over the last 11 years:

https://en.wikipedia.org/wiki/Helion_Energy#Development_hist...

The prototype currently under construction is Polaris. It's 25% larger than the previous prototype and they expect it to achieve net electricity production:

https://www.helionenergy.com/polaris/