In the context of electricity generation, a measure of a plant's productivity. A plant's capacity factor is equal to the amount of electricity it produces over a specified period divided by the amount of electricity that would have been produced if the plant had been running at its installed capacity during that same period. For example, a one megawatt generator that is operating at full capacity would produce one megawatt-hour (MWh) of electricity every hour or 8760 MWh in a year and would have a capacity factor of 100%. If instead it produced 5000 MWh of electricity for the year, its capacity factor is 57%. Different types of plants have different capacity factors based on:

Natural gas-fired, coal-fired plants, and nuclear power plants have the highest capacity factors.