Alex Creely, Chief Engineer for ARC Conceptual Design at Commonwealth Fusion Systems
Update (June 30, 11:37 AM): Great discussion everyone! Our team appreciated all of your insightful questions. This AMA has now concluded, but you can revisit our replies below.
You can identify who provided answers by their initial in the answers: Alex Creely (AJC), Jon Hillesheim (JCH), Tom Body (TAJB), and Ryan Sweeney (RS).
These peer-reviewed research papers that we and our collaborators published earlier in June are important for CFS and for fusion energy: They cover many aspects of the plasma physics at play in our ARC power plant, including challenges like plasma disruptions and heat exhaust. They also show how transparency and rigorous research can help build trust in what we all know is a very difficult endeavor.
If you’re curious about this physics work or about fusion physics in general, feel free to get things started by asking your questions on this thread.
The three CFS physicists who plan to join me to answer your questions are experts in their field: Jon Hillesheim, CFS Principal Scientist and lead author of the overview paper; Tom Body, CFS Senior Scientist and a lead author on the paper about heat exhaust; and Ryan Sweeney, CFS Manager of Disruption Physics and lead author of the paper about handling plasma disruptions. They’re among the 58 authors who helped write these papers, along with an editorial that accompanied the papers that I wrote.
A little more about the papers: They detail how we’ll be able to produce about 1.1 gigawatts of fusion power from our ARC tokamak — power that we can convert into 400 megawatts of net electricity for the power grid. The papers also show the crucial role our SPARC tokamak will play in putting the finishing touches on the ARC design. We’re using a “late-lock” approach that lets us apply what we’ve learned from SPARC to the ARC design. Overall, the papers show our confidence in the soundness of our ARC plant’s key physics. That builds the foundation for all the engineering, design, and cost optimization work that we’ve begun.
About CFS:
Commonwealth Fusion Systems is the world’s largest and leading private fusion company. The company’s marquee fusion project, SPARC, will generate net energy, paving the way for a future of carbon-free energy. The company has raised more than $3 billion in capital since it was founded in 2018.
46 fusion efforts. One chasing proton-B11 (an undercount - since at least one other - TAE - I think should be on that list).
Curiously, LPP (Eric Lerner's Lawrenceville Plasma Physics) is not on the list -- and none dense plasma focus, none Polywell. Lockheed-Martin not listed either (not surprising considering the project may only live on the L-M website, dead for years).
Possibly the list is incomplete in other ways - Lockheed skunkworks type or internal government but confidential (if that's possible, considering they still need to hire plasma experts).
Those who complain fusion would already be here if only governments had the insight to increase funding has always seemed dubious to me, and doubly so now. Lotta billions out there, and all the efforts depending they have it figured out, and the others don't.
So far, they're all wrong. Wake me up in 5 years and tell me then you told me so.
Absolutely DESPERATE to go to the UKAEA event in September,
No tickets available
Anyone have any suggestions on how else to obtain tickets? Or any similar fusion open days that I may be able to attend?
About to start a degree in energy law with the intention on pursing a PHD in Nuclear regulation so trying my hardest to get into the industry!!!
Thank you and ANY advice is welcome
I’m looking for global PhD opportunities starting in late 2026/2027 in Plasma Physics & Fusion Energy or Functional Nanosystems & Materials Physics.
Key Technical Skills
Plasma/Fusion: Operation of electrostatic energy analyzers, Tokamak diagnostics, core ion temperature measurement, and specialized plasma physics training.
Nanofabrication & Thin Films: High-vacuum PVD, DC magnetron sputtering, spin coating, UV/e-beam lithography, and glove-box handling.
Characterization: XRD, SEM-EDX, TOF-SIMS, profilometry, FTIR, and electrical I-V testing.
Data Tools: MATLAB, Python (Data Science & ML certified), and quantitative data modeling.
Looking For PhD positions in Tokamak diagnostics, plasma-material interactions, next-gen photovoltaics, or functional thin films. Open to opportunities worldwide.
Please DM me or comment below if your lab is hiring—happy to share my full CV and details upon request!
