Power line disturbance hold up times are dynamically adjusted based on battery capacity of a plurality of batteries in a plurality of racks by determining which one of the plurality of racks has a fewest number of remaining batteries of the plurality of batteries having the battery capacity. A determination of an amount of the power line disturbance the one of the plurality of racks, having the fewest number of remaining batteries of the plurality of batteries with the battery capacity, is able to support.