General Fusion offers a twist on LANL's research by using spherical force focusing reminiscent of Fat Man's explosives:
http://www.popsci.com/node/30516 "The source of endless energy for all humankind resides just off Government Street in Burnaby, British Columbia, up the little spit of blacktop on Bonneville Place and across the parking lot from Shade-O-Matic blind manufacturers and wholesalers. The future is there, in that mostly empty office with the vomit-green walls -- and inside the brain of Michel Laberge, 47, bearded and French-Canadian. According to a diagram, printed on a single sheet of white paper and affixed with tape to a dusty slab of office drywall, his vision looks like a medieval torture device: a metal ball surrounded on all sides by metal rods and bisected by two long cylinders. It's big but not immense -- maybe 10 times as tall as the little robot man in the lower right corner of the page who's there to indicate scale. What Laberge has set out to build in this office park, using $2 million in private funding and a skeletal workforce, is a nuclear-fusion power plant. The idea seems nuts but is actually, he says, not at all far-fetched. Yes, he'll admit, fusion is generally considered the kind of nearly impossible challenge undertaken only by huge universities or governments. Yes, fusion has a stigma to overcome; the image that it is fundamentally bogus, always and forever 20 years away, certainly doesn't help. Laberge would probably even admit that the idea of some Canadians working in a glorified garage conquering one of the most ambitious problems in physics sounds absurd. But he will also tell you that his twist on a method known as magnetized target fusion, or MTF -- to wildly oversimplify, a process in which plasma (ionized gas) trapped by a magnetic field is rapidly compressed to create fusion -- will, in fact, work because it is relatively cheap and scalable. Give his team six to 10 years and a few hundred million dollars, he says, and his company, General Fusion, will give you a nuclear-fusion power plant." <more> And from their web site: http://www.generalfusion.com/t4_mtf.php "Magnetized Target Fusion MTF is a fusion approach that is in between magnetized fusion (MF) and inertial confinement (ICF). In MF the plasma density is very low (1014 particles/cm2) so the fusion rate is slow and the plasma must be contained for many seconds in order to make more energy than initially invested in heating the plasma. This is hard because the very hot plasma tends to twist and escape the magnetic field. In ICF the plasma density is 1000 times the density of a solid (1025 particules/cm2). The reaction rate is enormous and the fusion energy is released in ~1 nanosecond. That is faster than the time for the plasma to cool down even if there is no attempt at preventing the heat from escaping. The problem here is that a lot of energy must be crammed in a very small spot, and in a very short time to achieve these conditions. The energy driver to do that (laser, particle beam) is difficult. In MTF a relatively cold plasma with an embedded electrical current is generated inside a conductive cavity. The electric current produces a magnetic field that helps confining the plasma in a similar way to MF. The cavity is then rapidly collapsed like in ICF. Because the magnetic field cannot penetrate the conductive wall, the plasma is compressed and heated to thermonuclear conditions. Because of the magnetic field the heat does not escape as fast as ICF so the compression can be slower and the peak density can be less (~1020 particles/cm2). Yet this density is one million times more than MF so the magnetic configuration must keep the heat for only 1 microsecond; a much easier task than MF. The slower rate of compression and larger plasma considerably relax the peak power and focus of the energy driver allowing a simpler, cheaper system to be used. Los Alamos National Lab in the US is working on MTF. In their approach, the cavity is a metal tube and it is collapsed by passing a large electrical current in it. The current reacts with the induced magnetic field to produce a force that crushes the tube." LANL's MTF web site: http://wsx.lanl.gov/mtf.html
