Magnetized Target Fusion - Challenges

Challenges

MTF is not the first "new approach" to fusion power. When ICF was introduced in the 1960s, it was a radical new approach that was expected to produce practical fusion devices by the 1980s. Every approach to date has sooner or later found unexpected problems that greatly increased the difficulty of producing output power. With MCF, it was unexpected instabilities in plasmas as density or temperature was increased. With ICF, it was unexpected losses of energy and difficulties "smoothing" the beams. These have been addressed in modern machines, but only at great expense.

MTF's challenges appear to be similar to those of ICF. To produce power effectively, the density must be increased to a working level and then held there long enough for most of the fuel mass to undergo fusion. This is occurring while the foil liner is being driven inwards. Any mixing of the metal with the fusion fuel will "quench" the reaction (similar problems occur in MCF systems when plasma touches the vessel wall). Similarly, the collapse must be fairly symmetrical to avoid "hot spots" that could destabilize the plasma while it burns.

Problems in commercial development are similar to those for any of the existing fusion reactor designs. The need to form high-strength magnetic fields at the focus of the machine is at odds with the need to extract the heat from the interior, making the physical arrangement of the reactor a challenge. Further, the fusion process emits large numbers of neutrons (in common reactions at least) that lead to neutron embrittlement that degrades the strength of the support structures and conductivity of metal wiring. These neutrons are normally intended to be captured in a lithium shell to generate more tritium to feed in as fuel, further complicating the overall arrangement.