Provided is a power generating apparatus including an evaporator configured to evaporate a working medium with a heating medium supplied from the outside of a working medium flow path, an expander to which a driven machine is connected and which is configured to convert expansion force of the evaporated working medium into rotational force to drive the driven machine, a condensing mechanism configured to condense the working medium discharged from the expander with a cooling medium supplied from the outside of the working medium flow path, the condensing mechanism having at least one heat exchanger pipe through which the working medium flows, a cooling water sprayer configured to spray cooling water as the cooling medium over the surface of one or a plurality of heat exchanger pipes of the at least one heat exchanger pipe, and a cooling fan configured to blow ambient air over the one or a plurality of heat exchanger pipes to evaporate cooling water attached to the surface of the one or a plurality of heat exchanger pipes, and a circulating pump configured to pressurize and supply the condensed working medium to the evaporator.