What is the P50-P90 annualized probabilistic production ?

[mmonesterio]

I reviewed a previous posting which almost gets me there (What is the P50-P90 probabilistic production ?) however i have a slightly different twist that i'm trying to resolve:

Using the TMY typical year i can model the P50-P90 (energy)for year 1, however how would i adjust energy statistically for year 10 or 20?. Assuming year 1 P50 production would escalate to year 20 due to confidence over time. I can get the Mean and Variance(RMS) from the first year's 8760 however not sure how i would apply that to adjust for year 2,3...

[André Mermoud]

The statistical distribution underlying the P50-P90 concept applies to a set of years.

If you have a TMY meteo data year, you will get a result corresponding to P50. But you cannot define a P90 value without further information about the statistical distribution of several meteorological years for this site.

The Average and Variance for the P90 definition are averages over several years. It has nothing to do with the hourly distribution.

Now defining a P50 or P90 value for the year 10 or 20 or any other one doesn't have any meaning.

The P90 yield for a given system, means a probability of 90% that the yield of any given year is above this value.