Capacity factor
Actual energy output compared with continuous rated output.
The filled quarter represents 25% of a full-output reference. This is an area comparison, not a time series.
Capacity factor is energy produced over a period divided by the energy that would be produced at continuous rated power over that same period. It reflects resource availability, operation, and outages.
Comparing output over the same period
Start with the energy a resource actually produced in a chosen period. Divide it by rated power multiplied by the number of hours in that same period. The result is a ratio, often expressed as a percentage.
Capacity factor is not conversion efficiency, and it is not a direct measure of reliability. Weather, maintenance, outages, dispatch decisions, and other conditions can all affect how much energy a resource produces.
Why it matters
It connects a power rating to energy delivered over time, provided the period and rating basis are stated.