Capacity factor

The ratio of the average load on (or power output of) a generating unit or system to the capacity rating of the unit or system over a specified period of time.

Average output compared to maximum potential output over a given period of time, usually expressed as a fraction. For example, a generating facility that operates at an average of 60% of its normal full-power capacity over a measured period has a capacity factor of 0.6 for that period. It can apply to an individual generating unit or a collection.

The amount of energy that a power plant actually generates compared to its maxumum rated output, expressed as a percentage.

An empirical dimensionless number that represents the ratio of the amount of power produced by a generating facility over a given period of time, to the amount of power that would have been produced over that time period had the facility operated at its rated capacity.