The reaction of fusion of heavy hydrogen isotopes with the formation of a superheavy isotope and a proton (2H + 2H → 3H + 1H) is studied by directing deuterium ions accelerated to an energy of 1.8 MeV to a deuterium target. The energy of the formed tritium nuclei is difficult to measure, and it is not measured. Only the energy of protons released perpendicular to the deuteron beam is measured, it is equal to 3.5 MeV. Determine the energy released in the reaction.