Systems to sell power back to the grid - to use your own solar power and any that you don't use can run the electric meter backwards - has one deceptive flaw: when the grid goes down your solar power is dead... UNLESS you wire with a special load switch AND add maybe $10,000 worth of batteries.
They make this power sharing deal seem attractive to the average homeowner but leave out important considerations. Consider spending $20k - $30k for a solar system on your roof able to produce 240vac @ 200 amps (a bare minimum.) Then when your grid power goes down - so does your solar system! The reason for that is simple: they don't want your system voltage feeding the grid while they are working on it to fix it.
As I say, you can invest another $10k+ on batteries and a load switch that blocks your power from feeding the grid while the power is down. It is easy to end up investing $50k - $80k - just to have a solar backup to relatively cheap grid power.
With the simple original hookup for most homeowners (without batteries), the investment tends to come to a break even status in about 7-8 years. The solar panels are generally good for 15-20 years. Batteries tend to only last 10 years, a bit longer with some battery types.
Myself, my modest solar system does not connect with grid power at all - except 'grounds' which are naturally the ground. I have a separate breaker panel with (for now) about 6 120vac circuits run through the house. All the receptacles are red in color so there can be no confusion. I may add 240vac circuits when I can afford more panels and batteries. My panels are NOT on my roof!
> when the grid goes down your solar power is dead... UNLESS you wire with a special load switch AND add maybe $10,000 worth of batteries.
Yep! Most people don’t realize this.
-SB