Batteries are Cheap, Backup power is expensive

Seems like good setup.  Of course it requires your manual involvement for switching, but your need would be different if you were away from home and unavailable.

The batteries should be adequate so long as the power is back on before too long.  How long is your typical outage?

@jwei 

We have at least 2 power "incidents" a month.  Sometimes it’s just long enough to reset the power on the microwave and oven.  Othertimes I come back and my surge protectors have turned off and have registered an "Extreme Voltage Shutdown" situation were either a brown out or white out has occurred.  

In terms of long term battery needs, about 1 time every three months.  This is at least the third time this year, and once was due to a storm, and once... was some other random thing.  

The complete lack of predictability is why I keep everything on a surge protector, whether that ruins the imaging or tactile feeling of the music or not.  (it does not).  

I was in a hurricane in New Jersey once that knocked out power for more than a week -- so many downed wires from fallen trees for the crews to clear.  I had a roundabout route over cleared roads just to get to the gas station to keep my generator fueled.  Bad luck.

@jwei - That's why propane generators are so attractive to me.  Even when you get an inverter type with sine wave output, their cost is modest and you can keep the fuel around for years outside if stored properly.  You also don't have to lug gas cans or the generator.  Just swap a tank in. 

For most home solar systems that are on the grid with no battery backup = zero power. The system shuts down automatically when power goes out. Power companies do not want their employees fried if there is solar power coming into their system.