lost firmware pw on macbookpro5,5 OS X10.11.6. Cannot accerss system revovery or some other sys commands

Lost power during elecrtrical storm and systems went down for about 2 or 3 hours. After power was restored my mac started request firmware password on boot with Command "R", "S", option key, I have tried many things with gui and with terminal commands just to have them rejected.

The system will boot into my supervisor profile but the error msg here is "you do not have autrhority to make the changes. I have and external backup boot drive but that is no help either but still will boot in el cap session no problem. Anyone who has advanced terminal commands would probably know how to hack the firmware so that a proprietary password can be used. Thanx for your attention.