Plant capacity factor (P.C.F) or capacity factor is the ratio of actual energy generated or supplied by a power plant over a specified time period to the maximum possible energy that could have been generated if power plant would have been operating continuously at maximum rating during that period. The plant capacity factor mainly depends upon the types of fuel used. The plant capacity factor is given by the following equation.
Plant Capacity Factor = (Actual Energy Generated or Supplied in Time T ) / ( Maximum Rating * T )
If we consider a period of a year then, the plant capacity factor will be,
Annual Plant Capacity Factor = (Annual energy Generated or Supplied) / ( Plant Capacity * 8760 )
Plant Capacity Factor indicates the extent of use of the generating station. If the power generation unit is always running at its full capacity then their capacity factor will be unity (1) i.e 100%. It is also given by the following equation.
P.C F = ( Peak Load / Plant Capacity ) * Load Factor
also,
P.C.F = ( Average demand ) / (Maximum Demand)
The plant capacity factor always has reserve capacity for the future expansion like increase in load or for maintenance. If the plant capacity is equal to peak load then the capacity factor will be equal to load factor.