A hybrid energy system including a controller that is coupled to at least one generator set and to at least one energy storage device. The controller is configured to cause the at least one generator set to operate at a first operational speed and a second operational speed in response to a change in the load. The controller receives notice that the at least one energy storage device is providing energy to the load and, in response thereto, to changes the amount of energy that the at least one generator set is providing to the load by causing the at least one generator set to operate at a third operational speed.