The effects of large rapid changes in generation from large arrays of wind turbine generators on the operation of automatic generation control and frequency regulation will be assessed. The maximum change and rates of change of generation from an array of wind turbines due to passage of a thunderstorm front is determined first. The assessment required (1) modeling an array of wind turbines in order to determine power variation for changes in wind speed caused by a storm front; (2) simulation of the model to determine power variation from a worst case coastal farm due to passage of a front; and (3) analysis of the maximum change and rates of change from the portion of the array affected by the front.