the local power company wants to charge out the ass to solar customers that are grid-tied, basically to make it as expensive as if you're buying power from them, and they want to pay jack and shit (and jack left town) for power that you sell back to them.
Of course this will vary by situation, but why not use the grid for things that need it, and use solar for things that don't?
For example, you might power an air conditioner totally with solar. That could be one of the biggest energy consumers in your house. The air conditioner could just be connected directly to the solar. The power company doesn't even have to know. From their PoV, it's just this guy that doesn't use much. Let the power company have the crumbs, like night-time lighting and the fridge, which don't work well with just solar.