In addition to what kungchuking and ThisIsNotSam said, you can export the power waveform as FSDB, and then open it using Verdi. There is an option to export in CSV format.
I did that a long time ago, but I figured out that the CSV file is just so huge that I'm not able to process it.
Anyway, in case you decide to continue, make sure you set the units of {internal, leakage, switching} power int PrimeTimePX before exporting the FSDB file, because otherwise, you will get a CSV file with values in several units (some in mW, some in W ...etc).
Good luck.