This is a PW1500G engine on a CSeries
Fan diameter on this one is 1,85m, so an average man can stand straight inside the engine. Notice that you can see light coming through the engine? That is because it has a very high bypass ratio (12:1), which means that most of the thrust is actually produced by the fan (these blades that you can see on the picture) and relatively small amount is produced by the air coming out of the turbine itself. That is what makes these engines very fuel-efficient!