The
availability factor of a
power plant is the amount of time that it is able to produce
electricity over a certain period, divided by the amount of the time in the period. Occasions where only partial capacity is available may or may not be deducted. Where they are, the metric is titled
equivalent availability factor (EAF). The availability factor should not be confused with the
capacity factor. The capacity factor for a period will always be less than the equivalent availability factor for the same period. The difference depends on the utilization of the power plant.