We usually use induction motors to turn electrical energy to mechanical, however synchronous motors are the machines on the other side of the grid (generation).
A week ago we had a student visit to the hydroelectric and ... centrals and afterward we paid a visit to a steel company. I noticed that they use the combination of the synchronous and induction motors to do the exact same job, so the output power of the motors were exactly the same so the task and the hours of operation.
Why just not using induction motors ?