[en] The paper describes the fuel elements as an effective energy conversion technology. The schematic diagram, some basic fuel elements characteristics and theirs priorities over the traditional technologies are given. Several kinds of fuel elements depending on the used electrolyte are briefly presented. According to the data from thirty power plants using fuel elements operating in USA, the annual economic effect is from 16 000 $ to 103 000 $ respectively. In conclusion the author considers that in countries like Bulgaria, importing over 70% of theirs energy resources, the fuel elements use is absolutely mandatory