First amateur polywell fusion reactor, in a Brooklyn apt

http://prometheusfusionperfection.com/2011/08/02/sydney-experiment-we-have-electron-confinement/

by joewadcan • 15 years ago

75 32 15 years ago

prometheusfusionperfection.com

rubyrescue• 15 years ago

what are the implications of this?

MrMan3• 15 years ago

fusion funds, energyscript, claims that lisp is better than fusion.

MrMan3• 15 years ago

schemaless fusion, lots of advice about "how I got fusion."

"Top 10 reasons your fusion is not reaching customers."

MrMan3• 15 years ago

fusion on rails. VCs telling 22 year-olds that they are changing the world - one electron at a time.

hugh32• 15 years ago

None. It's just a cool amateur electronics project. Energy in >> energy out.

In fact, I'm assuming and hoping for the sake of his neighbours that he's not actually attempting fusion. If I recall correctly, doing actual fusion with one of these requires deuterium and tritium and produces a crapload of neutrons for which I really doubt he has adequate shielding.

I'm pretty sure the experiment which he's attempting to replicate was never done with deuterium-tritium either, for similar reasons.

sp332• 15 years ago

I'm not sure about this one, but I know polywell reactors can be hot enough to use deuterium-deuterium reactions. It's cheaper, easier to extract energy from, and leaves stable helium nuclei with no stray neutrons.

sbierwagen5• 15 years ago

  In fact, I'm assuming and hoping for the sake of his neighbours that 
  he's not actually attempting fusion. If I recall correctly, doing 
  actual fusion with one of these requires deuterium and tritium and 
  produces a crapload of neutrons for which I really doubt he has 
  adequate shielding.

Yes and no.

The very lowest-energy-threshold fusion reaction is deuterium-tritium, so must research tokamak reactors use that. The JET[1], ITER[2], et al.

But tritium is both expensive and excitingly dangerous, (It's an alpha emitter, which is ordinarily harmless, since the alpha particles aren't energetic enough to penetrate skin; but it's a radioactive gas, not a solid, so you can inhale it and get all sorts of amusing cancers) so real amateurs prefer Deuterium-Deuterium fusion, and the kind of fusion reactor that that produce the higher energies needed to accomplish it, known as fusors[3].

D-D fusion does produce neutrons, you are correct. But the PF reactor is a pulsed device, with a tiny coil size: it doesn't make many neutrons, and it produces them for seconds at a time. This guy has been checked out by the NYFD, and they've signed off on the project. If it was a power reactor, neutron emission would be a problem, but it's not, so it ain't.

1: http://en.wikipedia.org/wiki/Joint_European_Torus 2: http://en.wikipedia.org/wiki/ITER 3: http://en.wikipedia.org/wiki/Fusor

WordSkill• 15 years ago

To be remembered down through the ages as the Great Vaporization of Brooklyn, August 3rd, 2011.

sbierwagen5• 15 years ago

Nope.

Fusion reactors are fundamentally different from fission reactors. You have to get a tenuous wisp of hydrogen (the reactor in this particular experiment was running at 10 mTorr, or 0.0013% atmospheric pressure) very, very hot, and keep it away from solid matter, which is millions of degrees of colder than the fuel plasma, and will suck all of the energy out of the reaction.

You shut off the containment coils, and tremendously hot plasma ions leap away from each other, instantly stopping the reaction. If the reaction somehow "runs away", which it absolutely can't, then it brushes the walls of the vacuum chamber, poisoning it with cold metal ions, like injecting lead shavings that have been chilled to absolute zero directly into your heart.

If our magical "runaway reaction" somehow overcomes this, and melts a hole in the vacuum chamber, then the atmosphere rushes in, both freezing cold and at intolerably high pressure, like the North Sea flooding into the hull of a submarine resting on the ocean floor.

Fusion reactors don't melt down, or explode. At all. It just can't happen, much like how a Yugo rear-ending a garbage truck in Brooklyn doesn't instantly consume all of New York City in a gasoline fireball.

It is indicative of the great difficulty of both starting and sustaining a fusion reaction that the only fusion reactions which produced more energy than they consumed, that have ever taken place on Earth were powered by atomic bombs, and still only ran for fractions of a second.

sliverstorm2• 15 years ago

Way to inject lead shavings that have been chilled to absolute zero directly into the best joke I've heard today :)

jcrites• 15 years ago

It's worth calling out that a cubic meter of the sun's fusion reaction generates about the same power as an active compost heap. http://en.wikipedia.org/wiki/Sun#Core - the huge energy output is due to the huge volume

endian• 15 years ago

Nitpick: It's not an apartment, it's a shared lab space near the Marcy Projects. I visited a while back and it was cool.

Awesome work, Mark!

sbierwagen5• 15 years ago

There was no actual fusion reaction occurring in this test. He just confined electrons in an air plasma. No hydrogen was injected.

And, of course, it didn't take place in an apartment.

VladRussian• 15 years ago

well, starting from 20-30KV the plasma may start radiating X-rays (bremsstrahlung).

emeltzer• 15 years ago

Haha, I interviewed this guy for a position a while ago and saw his reactor and workshop. It's totally boss but it wasn't in an apartment but rather in a huge warehouse workshop space.

First amateur polywell fusion reactor, in a Brooklyn apt

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