Excerpt from the daily Bloomberg's Green newsletter (It's free btw):

Summary:
- Investment flows are at a record high as interest grows
- Some startups are nearing the "net-energy gain" threshold
- Innovations on multiple fronts are driving fusion tech forward, such as better heat resistant materials, new reaction and plasma confinement methods, and advanced computing models
- Practical headaches are still great. Safety concerns are a key issue as materials need to withstand stellar heat for decades without failing

Abstract:

- Private-sector fusion companies in North America and Europe attracted $300 million in investment in 2020, about 20% of their historical total. This year's total may beat 2020 and 2019
- TAE Technologies, based in Orange County, California, has raised $880 million over its 23 years in existence; at least 15% thereof it this year
- First Light Fusion, which grew out of the University of Oxford, raised at least $25 million in 2020 for reactor development
- The promise of these start-ups has drawn attention and resources from high-profile investors looking for carbon-free power. Backed by Jeff Bezos, General Fusion is expecting to build a test facility in the U.K. that switches on by 2025; a commercial plant should follow well within a decade
- Energy companies including ENI, Equinor, Cenovus, and Chevron have invested in fusion
- Interest is so high that the U.S. federal government included $4.7 billion in authorized spending for nuclear fusion and related science in a bill passed in December 2020; the total includes $1.5 billion for ITER
- Scientists have yet to start a fusion reaction that sustainably produces more energy than it uses. But excitement has grown as government and private plans move incrementally closer to the breakeven or "net-energy gain" threshold
- Progress has come from several innovations. Some advances are technological, such as using lasers to confine reactions. Another is advanced computing, which has let engineers design machines to a precision previously unthinkable. One beneficiary of such innovation took another step toward reality this month when German scientists made progress on a device called the Wendelstein 7-X
- A third is all the private sector attention. If one of the startups reliably reaches "ignition"—the holy grail of producing more energy than the reaction uses—it can turn to building plants safely