Grid Tie systems still use a battery to store generated power. However, they "Buy" power from the grid when you are using more than you are generating and your batteries are quite flat. If you have full batteries and you are generating, they "Sell" extra power. To "Sell" power and get paid, you need a special meter. If the grid gets turned off, in your house it is business as usual. However, buying power is no longer an option. If you turn off the fridge and the A/C, you might be just fine for a couple of days without the grid. Grid tie lets you save on batteries (which are really expensive)

As far as I am concerned, political correctness is the act of phrasing your own speech in a less offensive manner. Censorship is muzzling someone else's speech which you don't like.