A new principle is outlined for generating electrical power by ultilizing decay energy of the waste radioisotopes. The electromagnetic radiation emitted by βparticles in a magnetic field can be used in the energy conversion process. If this principle is combined with the beta voltaic effect

the theoretical energy conversion efficiency limit would be 62% for using 90Sr-90Y β source. The practical efficiency would be on the order of 27%. The preliminary experimental results showed that the efficiency of the beta voltaic process might be more than 14.2%.