Yes, it’s a good news, less-than-good news situation. The good: If you fly IFR in a big-engine single and are concerned about keeping the electrical system alive for longer than any available batteries will live after the alternator gives up the ghost, there is probably a standby alternator retrofit for your airplane. While you may still have to do some electrical load-shedding, we think that’s a great thing.
We’ve lost alternators in VFR and IFR and, especially out West, have been amazed at how slow the airplane suddenly becomes when trying to divert and shoot an instrument approach before the available battery backup(s) also expire.