Many electric power utilities, such as Hydro-Quebec, are capacity limited despite having enormous energy surpluses. When demand and supply fluctuate, frequency control guaranties that the nominal network frequency remains constant. Frequency control can be applied on generation as well as demand side. This paper investigates the application of optimal demand side frequency based load control (OLC) for primary frequency regulation by comparing the performance of OLC and turbine governor action. This kind of comparison may be of interest to power utilities seeking improvement of the efficiency of their power plants. Also presented is a comparative investigation of the effects of choosing different disutility functions on OLC performance with respect to nadir and steady state error. The detailed simulation is performed using SimPowerSystems (SPS) toolbox, in phasor mode, on the IEEE 39-bus New England test system.