a few fundamental things will differ, with different fusion approaches: among them the reaction rate, and the energy conversion efficiency.
for fusion to occur, atoms either have to strike each other hard enough (high temperature), or be held in close proximity for long enough (high pressure); and these cost energy. heat can leak out of the reaction chamber, materials and fields can only be so strong, and plasmas are extremely corrosive. these facts affect the size and shape of the reaction chamber.
many fusion approaches attempt to scale the reactor based on a steady, sustained reaction. whereas DPF does fusion in short pulses.
then, after fusion occurs, how do you extract energy? perhaps with a heat engine, or by transforming electromagnetic fields.
efficiency of a heat engine depends on the difference in temperature between the hot chamber and the cool one. this is limited by the materials you choose, to make the chamber.
efficiency of an electric transformer depends on voltage, current, pulse width and shape, and period of firing, and likewise is also limited by the materials chosen.
a single proton-boron reaction produces 8.7 MeV of energy, from a collision in the hundreds of keV range. while this is a gain of more than ten to one, a single reaction is only about a trillionth of a joule. obviously, you need to get many of them going at once, before you can make the reactor do useful work.
all these approaches introduce variables that differ, affecting break-even.
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