You are describing a rational, reasonable regulatory system. :) Sadly, not the one in force.
I don't know where the full building code which would require this is, but this describes it in part:
> Florida State Generator Law 526.143 > Alternate generated power capacity for motor fuel dispensing facilities
> As of June 1, 2007, all retail outlets selling motor fuel must be able to operate its distribution loading racks using an alternate generated power source ... Installation of appropriate wiring, including a transfer switch shall be performed by a certified electrical contractor.
It has a single emergency outlet that will provide up 1500w when the grid is down. With the power being down last week from Irma it was able to output at least a 1000w load even with heavy overcast. It will off course shut off if it can't provide the attached load.
If you have a solar system for home its going to have an inverter, but most likely no batteries, some inverters can provide emergency power without them.
Batteries obviously work much better for that scenario allowing them to buffer energy. But nearly all grid tie systems installed do not have batteries due to extra cost and maintenance.
If so, it demonstrates that the article is, uh, not well researched.
The inverter doesn't backfeed for emergency power, it just has a separate output wired to a single outlet for emergency power.
But the article would have us believe that it is illegal to use those inverters in Florida.
Main issue I have seen with the law in FL for them is that they are net metered but the power bill can't go negative. So if they produce more than they use the power company doesn't have to pay them for it, also they always get a service charge no matter what. So their power bill ends up being about $20 a month no matter what which is just the service charge.
Now that 280 watt panels are becoming common, up to 7kw is a "standard" install.
I don't know about three phase.
That has nothing to do with powering you own home from you own solar panels.
When the grid-tie inverter senses the grid is down (it could even be scheduled outage for maintenance) - it stops feeding the grid and only powers the house. When it senses the grid is back it ties to the grid again.
If you need to work on the house, there can be a master switch where the panels come into the inverter (law in Australia) so you can manually turn them off, thus ensuring none of the house has power.
Simple.