Résumé : Energy cogeneration apparatus comprising a gas microturbine fueled by a vortex type combustion chamber (1) for producing a flameless combustion mode and with at least one heat exchanger-heat exchanger (3) for preheating compressed combustion air from a compressor of the microturbine before injection of this preheated air into the combustion chamber (1), characterized in that the combustion chamber (1) essentially comprises a cylindrical chamber (2) comprising: - a central tube (5) such that the preheated air is introduced at a first end of the chamber (10) into a first annular zone (7) located between the outer wall of the combustion chamber (2); ) and the central tube (5); - at a second end of the chamber (11), oriented slots (12) and injections of fuel gas (4) at the central tube (5), arranged to rapidly rotate the preheated air introduced via said slots (12) inside the central tube (5) in a flow vortex parallel to the axis of the combustion chamber and to ensure the intimate mixing of the preheated air, the fuel gas and the combustion gases. combustion inside the central tube (5) at a main zone and central combustion (8); an annular outlet (14) for the combustion gases situated at the level of the central tube (5) at the first end (10) of the chamber (2) and connected to a distributor of the turbine.