Fusion Energy Release A large amount of energy is released by nuclear fusion reactions. It seems that for power generation, the deuterium-tritium reaction is the most practical, but it provides most of the energy to the released neutron. That is problematic because it is harder to extract the energy from neutrons compared to charged particles. The deuterium-deuterium fusion divides its output energy between neutrons and protons. The proton fraction interacts by the electromagnetic force with the medium and converts its kinetic energy to thermal energy very quickly. It is practical to examine the kinetic energies of the products of nuclear fusion in the center of mass frame of reference. This amounts to neglecting the kinetic energies of the reacting particles before the fusion, which is justified by the fact that those energies are usually in the 1-10 keV range, and the fusion yield is in the MeV range. In the CM frame the energies of constituents a and b in terms of the fusion energy release Q are: The magnitudes of the momenta in that frame are equal: Combining these two equations gives: This allows us to determine the relative magnitudes of the energies of the two fusion products: For D-D fusion, the smaller particle carries 75% of the energy. With m(He 3 ) = 2.8084 GeV/c2, m(H 3 ) = 2.8089 GeV/c2,m(n) = 0.9396GeV/c2, and m(p) = 0.9383GeV/c2, the product energies for deuterium-deuterium fusion are shown. With a total yield of 3.27 GeV for the neutron reaction, the neutron carries 74.93% of the yield. For the proton reaction with yield 4.03 MeV, the proton carries 74.96%. For D-T fusion, the smaller particle carries 80% of the energy. With m(He 4 ) = 3.7274 GeV/c2 and m(n) = 0.9396 GeV/c2, the product energies for deuterium-tritium fusion are shown. With a total yield of 17.59 MeV for this reaction, the neutron carries 79.87% of the yield.