Internal combustion engine and cogeneration device

摘要

Provided is an internal combustion engine capable of improving energy consumption efficiency on a full year basis. A gas engine (1) comprising an oil cooler (11), wherein the oil cooler (11) has a channel that exchanges heat between an engine coolant and a lubricating oil, and the gas engine comprises a controlling unit (12) that controls the temperature of the engine coolant to a constant temperature so that the lubricating oil is cooled during high load operation and the lubricating oil is heated during medium load and low load operation. The controlling unit (12) is configured to increase the temperature of the engine coolant to be higher during medium load and low load operations when compared to the same for high load operations. The engine is provided with an oil jet (18a) that injects lubricating oil to the back face of a piston (17).