There is an entire thread about grid charging and the savings/no savings associated with it. My issue is a bit different. I just had a power shut down that brough my batteries from 100% to 36%. Now we're back on the grid, so power is on, but batteries are still at 36%. It is almost 9PM here (so Off-peak), and it would be nice to keep the batteries replenished to a level that I would not be in the dark on the next power outage,
There was a major fire nearby, so powerlines are being repaired, but the grid electricity is on and off, on and off. It would just be a nice peace of mind if I could just replenish some of the batteries for the next outtage.