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Using percentage of deuterium burned as a measurement of fusion energy, LPPFusion’s results are far ahead of those of competing private fusion efforts, even though those competitors have spent tens or hundreds of times as much money.
Using the same measurement, LPPFusion is not far behind government programs that have spent thousands of times more money that we have. Note different scale from first figure.
Deuterium-Tritium Fusion with Tokamaks
Nuclear fusion has the potential to generate power without the radioactive waste of nuclear fission. But most fusion research today is focused on fusing deuterium and tritium using tokamaks, which are large, highly-complex devices. When deuterium and tritium are heated to sufficiently high temperatures (about 300 million degrees), they fuse, producing helium and high energy neutrons. These neutrons create heat and radioactive materials just as in a fission reactor.
Deuterium and helium are not radioactive and occur in nature. Tritium, however, is radioactive and does not occur in nature. It must be created in the reactor by using neutrons. So deuterium-tritium fusion still has two of the disadvantages of nuclear fission:
- The high-energy neutrons can take ordinary materials in the reactor building and make them radioactive
- Some of the fuel—tritium—is radioactive.
- In addition, tokamaks are by their nature very large, expensive and complex devices, using powerful magnets to keep the hot plasma in place. It is not at all clear that they could ever produce net energy, but if they did, it would be more expensive than that produced in fission reactors, since the steam conversion would be the same, and the energy producing core would be more expensive.
Comparison with Focus Fusion
In contrast, Focus Fusion reactors using the plasma focus device and hydrogen-boron fuel would produce almost no neutrons at all and no radioactivity induced in the structure. The energy comes out as a beam of charged particles, helium nuclei or alpha particles, which can be converted directly into electricity, making the reactors compact and cheap.
In addition, the plasma focus device uses natural plasma instabilities, rather than trying to get rid of them as all other approaches do. Since we are aiming for a very dense plasma, we also don’t have to confine the ions for a long time–just a thousand or so orbits around our tiny plasmoids. The other approaches, like the tokamak have to confine their ions for hundreds of millions of orbits. Plasmas that are that stable simply don’t exist in nature. So our task is far easier that theirs, which is why we can make so much progress with so little money. (Although we can certainly use some more!)