May 01, 2007

Follow up on rapid-fire Z-machine Fusion

Pessimistic timetables for commercializing the rapid fire are 30 years or more. However, one of the skeptics is Ian Hutchinson who is a strong supporter of the Tokomak ITER (International Thermonuclear Experimental Reactor) project.

Even if money were no object, it could take 30 years to build a system, says Keith Matzen, director of pulsed power projects at Sandia.

Others think the engineering challenges involved in harnessing rapid series of large explosions are likely to prove just too difficult. With the new device, says Ian Hutchinson, professor of nuclear science and engineering at MIT, the Sandia and Tomsk researchers have scaled a 500-foot hill. The work they've yet to do is the equivalent of a 25,000-foot mountain. Several other researchers concur, noting that the Sandia researchers must also demonstrate that the system can produce the levels of fusion that their models predict.

The Sandia device stores energy in a group of large capacitors and releases it very quickly, in just 100 nanoseconds. A new kind of physical arrangement of these capacitors prevents magnetic fields from forming and slowing electrical current, a major problem with previous devices. But while acknowledging that the technology is an important advance for delivering pulses of power, several experts say a power plant based on such technology faces significant hurdles, not the least of which is building the plant sturdy enough to withstand the strong explosions going off every 10 seconds.

One thing to note is building the plant sturdy enough to withstand the explosions is less of a problem when using the system for pulsed nuclear rockets.

Whether it is 10, 20 or 30 years or more until fusion is scaled up we should press on with scaling up nuclear fission including thorium reactors and solar and wind power

The New Scientist magazine online also has an article on this

The LTDs were developed by researchers at the Institute of High Current Electronics in Tomsk, Russia, in collaboration with Sandia colleagues. Each "spark plug" is about the size of a shoebox and contains a switch coupled to several large capacitors. A circular ring of 20 such units, wired in parallel, can produce half a million amps and one hundred thousand volts. Linking several rings together increases the final voltage produced. Researchers estimate that about 60 rings should be enough to power a fusion reactor.

Here is a link to my original article on the rapid fire z-pinch fusion system