Cogeneration apparatus

A cogeneration apparatus (10) having a ventilation-introducing channel (61) communicating an electrical-equipment compartment (20) with a ventilation fan (57) is disclosed. Driving the ventilation fan (57) causes air to be led from an exterior (40) of a cogeneration case (11) through the electrical-equipment compartment (20) to the interior of the ventilation-introducing channel (61). The air led to the interior of the ventilation-introducing channel (61) is led to an electrical generator (18). The air led to the electrical generator (18) is exhausted through a power-generation compartment (12) to the exterior (40) of the cogeneration case (11).