The invention relates to a method and apparatus that provide autonomous power supply by converting energy of sources of a non-electrical nature into the electric energy using charge generators. For such apparatuses, as charge generators can be used piezoelectric elements, triboelectric elements, as well as radioactive sources of charged particles that do not require periodic replacement of re-charging-in contradistinction to the convention sources of power supply, galvanic batteries. Charge generator (1), when activated, produces a portion of electric charges q having a high electric potential Uin, which portion is applied to the input of charge energy converter (2). The function of the converter (2) is to increase the initial value of charges q up to value of Q, with simultaneous reduction of their potential to Uout value, which less than Uin. For the purpose to store charges Q obtained as a result of the conversion, which charges Q are needed for the electronic systems power supply, electric charge storage (3) is positioned at the output of the apparatus.