What was the earliest diesel engine?

[BrandonDella]

The earliest diesel engine was successfully manufactured by Diesel as the world's first experimental diesel engine (bore 15 cm, stroke 40 cm). In 1890, Diesel returned to Berlin and devoted himself to the study of power engines. Diesel hoped to create a diesel engine that was better than gasoline engines. By 1897, theoretically, diesel engines had higher efficiency than gasoline engines and were more suitable as power sources for ships; additionally, diesel engines did not require electronic ignition, and the diesel fuel they used was cheaper than gasoline. The first engine had a power output of 13 kW, with small heat loss and an efficiency of 38%, far surpassing that of steam engines and gasoline engines. Soon, this type of machine became widely used as a stationary engine in power plants. After continuous improvements, it is now not only used in ships but also widely applied in large buses and trucks.