You need a way to turn off the power. Normally there's a fuse/switch where the power enters the building, and that's it.
This kind of PV is popular in the city where I live. I feel queasy about there being sources of power that don't pass the main fuse. I'm sure there are ways to make it safe, but I like the simplicity of having one fuse between power supply and power users.
Right. This is my concern, too and it's why you shouldn't _just pipe your generator into the dryer's outlet_ when the power goes out. The electricity will continue to feed back out into the grid and can hurt/kill line workers who aren't expecting power.
Reading between the lines here, though. Maybe the device has a buffer and some mechanism to detect when the grid goes down and will only send it back into the outlet if things are operating normally? This is very clever if it somehow works and is safe but, yeah, it also makes me queasy and is the reason it's only available for sale in Utah.
Grid-tied inverters only push power if it senses the grid. It’s a standard feature and has been around for years. Off grid inverters push no matter what. The situation you fear is somebody not knowing what kind they have and just plugging it in.
This kind of PV is popular in the city where I live. I feel queasy about there being sources of power that don't pass the main fuse. I'm sure there are ways to make it safe, but I like the simplicity of having one fuse between power supply and power users.