ENGINE EXHAUST ENERGY RECOVERY DEVICE, SHIP PROVIDED THEREWITH, AND POWER GENERATION PLANT PROVIDED WITH SAID ENGINE EXHAUST ENERGY RECOVERY DEVICE

An object is to provide an engine-exhaust-gas energy recovery apparatus that can set the fuel consumption rate of an engine to a predetermined value or lower in response to various loads and rotation speeds of the engine, and that can effectively utilize exhaust gas discharged from the engine. Provided are a hybrid turbocharger (3) having a turbine unit (3a) that is supplied with exhaust gas discharged from an engine (2), a compressor unit (3b) that pressure-feeds scavenging-air pressure to the engine (2), and a generator/motor unit (3d) that generates electricity when the turbine unit (3a) is driven; a bypass channel (L2) that allows the exhaust gas supplied toward the hybrid turbocharger (3) to bypass the hybrid turbocharger (3); an engine-load detecting part; an engine-rotation-speed detecting part; a scavenging-air-pressure detecting part; and a control device having a database for calculating a scavenging-air pressure, at which the fuel consumption rate of the engine (2) becomes lower than or equal to a predetermined value, from the detection values of the respective detecting parts. The control device controls an exhaust-gas bypass control valve (V1) so as to control the scavenging-air pressure of the engine (2).