Embodiments provide systems, apparatus, and methods for power distribution operated under automatic generation control (AGC) based on reliability based control (RBC) green zone control. Embodiments include a plurality of power generating resources operating within a control area; a plurality of power consuming loads; a power transmission network coupling the resources to the loads; and an energy management system (EMS) in communication with the resources and configured to control operation of the resources within the control area, wherein the EMS is operative to: determine a reliability based control (RBC) green zone; operate an automatic generation control (AGC) system of the EMS within the determined RBC green zone; and output electricity to the loads from the resources under the control of the AGC of the EMS operating within the RBC green zone to correct area control error (ACE). Numerous additional aspects are disclosed.