My home is 1930s, it's fuse, in the black Bakelite housing typical of the era was insufficient and we were missing a incoming breaker to/from grid, those were updated. Our meter is much more recent, though still dated; allegedly it would have worked but it wasn't a smart meter, which we wanted so we had that updated.
I've also heard through my many hours of watching Solar videos on YT before our install that some breakers, RCDs(?), RCBOs(?), whichever it is, aren't always suitable for bidirectional current flow, so that's a possible issue too.
All of that is aside the "suicide cord" danger of the old generator method, but that's gone now with modern tech, the output is cut before you can get your hands on the contacts on the end of a plug.
It's just been legalised here in the UK, and I think it will help people with their bills, but the key is to keep installation costs down; if it's DIY you can look at a decent ROI time, but with the cost of trades-people these days, if you have to call out a sparky to inspect before you plug it in, you've added potentially years to your payback period.
At ~800W, I think on the whole we'll be fine; the equipment in our homes has got much more efficient over the years, and our homes were mostly built for times where we were using higher powered devices. If you can draw over a kW to power an electric heater or kettle, I don't see why feeding a mere 800W back in would be a huge risk.
Disclaimer: I'm not an Electrician, but I do have a degree in Electronic Engineering.
The solar is the same way, but with an auto cutoff.
Yes, but that's dangerous for reasons[1] that people often don't bother explaining -- and that aren't important for solar grid-tied inverters[2].
[1]: The seemingly-ideal way to plug a big fat generator into an American house in a hurry is to use a double-ended suicide cord to feed into the 240v dryer outlet. That provides plenty of power to get a lot of things done, it's a single-outlet circuit, and it lights up both sides of the split phase panel. But that's bad.
The most obvious way that it's bad is because we shouldn't have energized male prongs. Like, ever -- that's just extra shit to get hurt with. But this suicide cord idea relies upon their use.
The other way that it's bad is that the generator doesn't know whether the house is still connected to the grid or not. So unless we deliberately disconnect from the grid, there's a wonderful chance that we feed it even though that grid is presently non-functional. This can fuck people up: The transformer on the pole outside (or in the box down the way, or whatever) will cheerfully convert the sleepy 240v from the generator into thousands of volts on the wires outside that were completely dead until someone decided to get clever. Now, the guy cleaning up storm debris down the block or the lineman doing the repair gets the fuck shocked out of them in spooky-dead kinds of ways. (Yeah, yeah: We shouldn't ever do anything near downed lines of any kind, and the lineman should always have appropriate PPE. And we shouldn't plug our generators into our dryer socket, too. Death is permanent.)
Panels with interlocks and wall-mounted male sockets that accept generator input both exist, and the combination of them mitigates both issues. The combination also prevents a third problem: Power coming back on while the generator is running.
[2]: But a proper UL-listed plug-in solar inverter doesn't have any of these problems. The issues are sidestepped because it outputs nothing when the grid is down, as a baked-in function. So there's no energized male plug to be a hazard, and there's also no interlock required to ensure that the grid isn't backfed while it is down. You can hypothetically unplug the solar inverter from the wall on a bright sunny day and lick the prongs, and nothing happens.
This has very little to do with the power meter itself, and more that the power company wants to be able to monitor if the meter is 'running backwards' (i.e., if power is flowing out rather than into the meter). Older meters could only run in one direction.
> Clearly some people think of it differently if they're plugging generators into wall sockets to power the whole house, dumb as that may be.
There's frankly nothing wrong with this if you do it properly. The 'proper' way would be to have a generator input socket near the main breaker panel, and the main breaker is interlocked with the generator input (i.e., only one can be on at a time). You absolutely can just plug a regular generator into a wall, assuming you aren't overloading the wiring or breakers... the safety issue is overblown. The reason why it's 'super dangerous and bad stuff will happen' is because people are stupid and forget to turn off the main breaker. Which, admittedly, is a reasonable concern because... people do forget.
When we had our solar installed, we had to make sure we had a newer power meter that could handle power both ways, so it probably is a problem for some situations, but the power flow for a single solar panel into a plug isn't enough to trip this, or maybe newer power meters are better?
We definitely think of it as somewhere a power comes out of, but I don't think it's the name, just that it's only ever been that way.
Clearly some people think of it differently if they're plugging generators into wall sockets to power the whole house, dumb as that may be.