A method of electrically powering at least one electrical load in an aircraft, the method comprising: - providing a main source generating electricity and an auxiliary source for storing electricity connected in parallel with the main source via a DC/AC power converter, the method being characterized by: - an operation of the main source, the operation comprising: ∘ electrically powering said at least one electrical load by means of the main source; ∘ measuring at least one instantaneous parameter characterizing the main source; ∘ determining a level of use of the main source from said at least one measured instantaneous parameter; ∘ adjusting the voltage of the main source as a function of the determined level of use; - an operation of the auxiliary source, the operation comprising: ∘ measuring an output voltage from the main source on outputs of the DC/AC power converter; ∘ comparing the voltage measured on the output of the main source with a predetermined voltage threshold value (Vh); and ∘ electrically powering said at least one electrical load from the auxiliary source whenever the voltage measured on the output of the main source is less than the predetermined threshold value, so as to supply additional electric power to the electrical load, the operation of the main source and the operation of the auxiliary source being realized in parallel and independently from each other. - providing a main source generating electricity and an auxiliary source for storing electricity connected in parallel with the main source via a DC/AC power converter, - an operation of the main source, the operation comprising: ∘ electrically powering said at least one electrical load by means of the main source; ∘ measuring at least one instantaneous parameter characterizing the main source; ∘ determining a level of use of the main source from said at least one measured instantaneous parameter; ∘ adjusting the voltage of the main source as a function of the determined level of use; ∘ electrically powering said at least one electrical load by means of the main source; ∘ measuring at least one instantaneous parameter characterizing the main source; ∘ determining a level of use of the main source from said at least one measured instantaneous parameter; ∘ adjusting the voltage of the main source as a function of the determined level of use; - an operation of the auxiliary source, the operation comprising: ∘ measuring an output voltage from the main source on outputs of the DC/AC power converter; ∘ comparing the voltage measured on the output of the main source with a predetermined voltage threshold value (Vh); and ∘ electrically powering said at least one electrical load from the auxiliary source whenever the voltage measured on the output of the main source is less than the predetermined threshold value, so as to supply additional electric power to the electrical load, ∘ measuring an output voltage from the main source on outputs of the DC/AC power converter; ∘ comparing the voltage measured on the output of the main source with a predetermined voltage threshold value (Vh); and ∘ electrically powering said at least one electrical load from the auxiliary source whenever the voltage measured on the output of the main source is less than the predetermined threshold value, so as to supply additional electric power to the electrical load,