H/T Talk Polywell
Unlike many government-sponsored efforts, however, Tri Alpha is working with fusion reactions that produce fewer neutrons and, thus, less radiation, Mr. Rothrock says. The company also uses a different method for containing and controlling fusion reactions, which happen at million-degree temperatures. “It’s a long way from reality, but the trend line is going in the right direction,” he says. “The science is rock-solid; the calculations continue to bear out the results.”
Mr. Prouty estimates it will take his company “not 15 to 20 [years], but not 3 to 5 either” to go from the research stage to power generation.
TriAlpha is the brainchild of Norman Rostoker, a senior fusion researcher. He had previously collaborated with another researcher, Maglitch, on the MIGMA approach to advanced fuels. This approach involved shooting two counter-circulating beams of ions at each other in a confining magnetic field. It was not very workable, as the ion densities would always be very low. Rostoker combined this idea with another device, the Field Reversed Configuration, sending the beams into the FRC.
The FRC is essentially a large-scale plasmoid centimeters rather microns across, with much lower densities and magnetic fields than with the DPF. It does not benefit from the magnetic field effect as its field are far too low. Scientifically, TriAlpha’s results so far are very modest compared with focus fusion’s. The average ion energy, a measure of plasma temperature is a few 10’s of eV. This is a factor of 10,000 short of what is required for pB11 fusion. Of course, we have already achieved the needed ion energies (100keV) with focus fusion, so in this sense are way ahead. In addition, it is by no means guaranteed that their confinement will remain stable if they can reach higher temperatures.
Dr. Hendrik Monkhorst of the Quantum Theory Project and his collaborator, Dr. Norman Rostoker of UC Irvine, designed a novel type of fusion reactor called the Colliding Beam Fusion Reactor (CBFR).
CBFR in Field Reversed configuration has a cylindrical shape, rotates at a high rate about its axis inside a solenoidal magnet, and thus produces a magnetic field that closes upon itself: a kind of self-confinement of fuel nuclei was established, with all confined particles flowing in the same direction. Protons rotate at a high rate, with an energy of about 1 MeV, and Boron 11 are slower, which causes the protons to literally ‘rear-end’ the Boron 11 with an energy at which fusion cross-section is highest. The collaborators found that plasma parameters could be set such that essentially all injected protons and Boron 11 undergo fusion to 4-Helium which were guided into Direct Energy Converter (DEC) devices. These devices turned their kinetic energy directly into electricity, unlike previous techniques where water was boiled, producing steam which drove turbines to eventually produce electricity. Resulting advantages included abundant fuel supply, nearly no radioactivity, no danger of runaway reactions or explosions, scalability of size and output power, easier engineering and maintainability. They have begun a multi-faceted study which is currently underway to establish the full feasibility of the design. Many calculations, theory development and nuclear polarization (to enhance the fusion reactivity), is centered in the UF Physics Department.