Hacker Newsnew | past | comments | ask | show | jobs | submitlogin

It's an extremely misleading half-truth. Worse, Q must be an order of magnitude greater than 1 IIRC to be economically viable.


They did not mention Q at all in the article and their claims cannot be compared to any intellectually honest definition of "break even" in good faith without more information


IIRC from a recent HN discussion, ITER has attained Q of 0.65 and NIF is nowhere close to that.


Are you sure you're not thinking of JET[1]? ITER's not scheduled to be operational until 2020 AFAICR.

Incidentally when I went to see JET (it's up the road from me, not that far from Oxford) the scale of the thing was enormous. They mentioned that they'd had been able to sustain plasma for 600 seconds. I've got some pictures up[2] on flickr.

[1] - http://www.i15.p.lodz.pl/strony/EIC/ne/future_2_1.html

[2] - http://www.flickr.com/photos/z3r0kl3w/sets/72157623979315835...


I'm jealous you got to see JET.

One of my favorite stories is the disruption. This happens when things don't go just right, and all the plasma with its energy squirts onto one spot. This typically puts the equipment in jeopardy. People try to prevent it, but as they push the boundaries of what's been done, it's going to happen.

Keep in mind that there's only about as much mass in the entire chamber as in a few cubic centimeters of air; it's basically a vacuum. But what little there is is so hot, and there's so much energy wound up in the fields. When JET had a disruption, the entire machine, the largest tokamak in the world, LIFTED ITSELF OFF THE GROUND AND JUMPED A FEW FEET OVER.


The LHC beam-dumps[1] at CERN are also at that holy-shit-physics scale. A more explanatory article[2] also covers the superconducting magnet quenches, in which up to 10GJ of stored energy suddenly decides it really ought to be following Ohm's law again.

Any good refs for this disruption situation?

[1] http://lhc-machine-outreach.web.cern.ch/lhc-machine-outreach...

[2] http://www.symmetrymagazine.org/article/december-2007/protec...




Guidelines | FAQ | Lists | API | Security | Legal | Apply to YC | Contact

Search: