For those not familiar with the Polywell design, it's a refinement of the slightly more well-known Farnsworth Fusor. The fusor design is surprisingly simple; small versions can be (and have been) constructed by hobbyists that will successfully fuse hydrogen.
Unfortunately, the fusor has serious drawbacks--probably unsurmountable--that make it impossible to get net energy output from the device, though it does function competently as a portable neutron source.
The fusor design (as well as the polywell, in a modified fashion) differs from conventional approaches to fusion, in that it uses concentric, spherical mesh electrodes in a vacuum chamber with an enormous voltage between them. Positively-charged ions are accelerated toward the center of the device by the interior, negative electrode; any that pass through are repelled by the outer electrode, so ions oscillate through the center of the device at very high speeds until either striking and fusing with another ion or impacting an electrode.
The more sophisticated polywell design uses a form of magnetic confinement to trap electrons in the center of the device, creating a "virtual electrode" and reducing losses from ions impacting electrodes. Unlike the fusor, there don't seem to thus far be any significant theoretical barriers to net energy gain from the polywell design. The main issue limiting further development of the polywell concept has generally been a lack of attention and funding needed to develop and engineer larger and more refined versions.
The other thing to note is that it's small. I believe WB6 was roughly the size of your average CRT monitor.
The estimated cost for a full scale polywell is ~$100 million, less than 1/100th of ITER's estimated costs. It has the potential for commercial fusion energy by 2020, not by 2050 like ITER. This, of course, is assuming the larger scale Polywell designs will break even with WB8.
Thank you, I forgot to mention that. Assuming the polywell design works as hoped, it is likely to be much smaller and cheaper for the same output than other fusion reactor designs.
I've been interested for a while in the potential of IEC-type reactors, so I'm really looking forward to the results of this new work.
Reading the WP article it seems almost frustrating. Even if this doesn't work it still seems like it would be worthwhile to give them some more money and time. I can almost hear Bussard's thoughts.
I first read about this in an article in Analog Science Fiction magazine. The technology sounded cool but the venue of publication seemed inauspicious. . . I really hope this produces something.
Unfortunately, the fusor has serious drawbacks--probably unsurmountable--that make it impossible to get net energy output from the device, though it does function competently as a portable neutron source.
The fusor design (as well as the polywell, in a modified fashion) differs from conventional approaches to fusion, in that it uses concentric, spherical mesh electrodes in a vacuum chamber with an enormous voltage between them. Positively-charged ions are accelerated toward the center of the device by the interior, negative electrode; any that pass through are repelled by the outer electrode, so ions oscillate through the center of the device at very high speeds until either striking and fusing with another ion or impacting an electrode.
The more sophisticated polywell design uses a form of magnetic confinement to trap electrons in the center of the device, creating a "virtual electrode" and reducing losses from ions impacting electrodes. Unlike the fusor, there don't seem to thus far be any significant theoretical barriers to net energy gain from the polywell design. The main issue limiting further development of the polywell concept has generally been a lack of attention and funding needed to develop and engineer larger and more refined versions.
In short, this is excellent news.