The DC capacity of any solar power station in megawatts peak (MWP) is the accumulated peak capacity of all the solar modules which it contains. Solar modules are typically individually tested at the end of the production line so that the peak capacity of a system can be determined very accurately.
The capacity utilization factor (CUF) of a solar power plant is calculated by dividing the actual energy generated by the plant over a given time period, by the maximum possible energy that could have been generated at the plant’s rated capacity over that same time period. It is calculated using the following formula: Where:
For solar, the net maximum electrical capacity increased 700 times as it increased from 176 MW to 120 000 MW between 2000 and 2019 (see Figure 3). Electricity production capacity from wind mainly relies on onshore infrastructure.
Nuclear power plants are at the high end of the range of capacity factors, ideally reduced only by the availability factor, i.e. maintenance and refueling. The largest nuclear plant in the US, Palo Verde Nuclear Generating Station has between its three reactors a nameplate capacity of 3,942 MW.
Capacity factor is the electrical energy output over time relative to the maximum electrical output over time. For example, a 100 MW solar plant generating 225,000 MWh has a ~26% capacity factor (225,000 MWh / (365 days * 24 hours/day * 100 MW).
Every power plant has a listed nameplate capacity indicating its theoretical maximum electricity output. The capacity factor indicates how often a power plant operates at peak efficiency. A power plant with a 100% capacity factor means the power plant is producing electricity at its full potential all the time.
OverviewSample calculationsDefinitionDeterminants of a plant capacity factorCapacity factor of renewable energySee also
Nuclear power plants are at the high end of the range of capacity factors, ideally reduced only by the availability factor, i.e. maintenance and refueling. The largest nuclear plant in the US, Palo Verde Nuclear Generating Station has between its three reactors a nameplate capacity of 3,942 MW. In 2010 its annual generation was 31,200,000 MWh, leading to a capacity factor of: