A value which refers to the probability of an outcome. The higher the “P” factor, the more likely that a certain outcome will be met or surpassed.
Commonly used in wind or solar resource studies, a P factor may represent the minimum number kWh which WTGs or solar panels of a certain nameplate rating at specified places will generate, at a probability of 99% or 50%, etc. For a P99 probability, there would be only a 1% chance that WTGs placed in those locations would generate less than the stated number of kWh. Lenders and other investors use these factors for various purposes, including to determine the amount of debt a project can support.
P factors are also used in the estimation of ultimate recovery from oil & gas reservoirs. Thus the P90 recovery amount would be the value which has a 90% probability of being achieved or exceeded.
