[blake1]

Solar cells generate DC, but this is converted to AC with power electronics: the inverter is the main one. These are all just very high wattage semiconductors, but like all semiconductors, they can be destroyed by a transient event like a lightning strike, or a high fossil-fuel power plant dropping offline. To prevent the power electronics from being destroyed when this happens, they are protected by safety systems which "trip," and isolate them from the grid.

There are loads of designs for grid isolation, but most are big circuit breakers, and break the connection by rotating the conductor out of contact, powered by gravity or a spring.

So I think you're basically right, and right to be confused. The solar connection of the risk isn't really clear. But as far as I can tell, they're concerned about a positive feedback loop, where a thermal plant dropping offline will cause a solar plant to trip, which might cause other solar plants to trip. Perhaps solar plants' power electronics are more delicate, and more likely to trip, than thermal plants' switchyard gear. Again, it's not totally clear.

[parrellel]

A lot of the rules for disconnecting solar were written when solar wasn't expected to be a major part of the grid, so the logic has them trip because that was the sane default.

That's no longer the sane default and the utilities have been slow walking software and hardware updates to fix it.

...and now that might be a problem.

[gabereiser]

Worse still are areas where laws were enacted that _required_ you to get your solar from your utility vs your roof. Or there's a "minimum service fee" even though you don't consume any energy. In the early days you could "sell" your excess energy back to the grid. Now you can't and worse still, they don't know how to handle the infrastructure they have to meet the ever changing climates of the western United States.

[benglish11]

Where are you where you can’t sell excess electricity back to the grid? You definitely can here in SE Pennsylvania. Amongst the few people I know with solar panels on their roof it’s the most common scenario. Several of them have no battery either so they cannot store excess electricity.

[gabereiser]

Net-metering has only just been introduced in many southern states after much lobbying from power companies against it. Here in Florida (where I am now) it’s illegal to disconnect your house from the grid if you have solar. There’s a minimum “service fee” of $60 from FPL even if you only used $10 of energy.

In many other states run by a certain political party, they have been making it so your net-metered connections are selling back at wholesale rates instead of retail rates, or limiting just how much you _can_ sell back (sell limits).

When I used to work for an energy intelligence company back in 2017 it was worse with legislation across the Midwest and western states that prohibited solar on roofs and required homeowners to pool together for community solar projects (run by the power company) to get their renewable energy.

Now, most 47 states have some sort of net-metering at least for wholesale prices but more and more of them are requiring a minimum service fees and making hardships for people to live without them.

[tremon]

There’s a minimum “service fee” of $60 from FPL even if you only used $10 of energy.

I don't see how this is a problem: the maintenance of the electricity grid must be paid somehow, and this is more or less a flat, predictable cost. If you're coming from a situation where the maintenance was previously factored into the price of energy consumption (not a bad way), you're going to have to redesign your billing.

Are you arguing against a maintenance fee in general or just how much it costs?