Abstract: A method and installation is proposed for generating electrical energy in an open circuit for a gaseous fluid, comprising a compressor unit driven by a turbine receiving the compressed fluid after its passage through an exhaust gas heat exchanger, said method and installation further comprising a power generator driven by a gas turbine, the circuit also comprising a fuel cell receiving natural gas in its anode from an external source and receiving and gaseous fluid from the compressor unit as an oxidizing agent in its cathode, the electrical power originating from both the generator and the fuel cell forming the output of the method and installation.