adam2's post is pretty spot on for what is going to happen.

This is why I don't like everything being digital. You're going to have to protect the grid by shutting it completely down. You'll have to start with all of the nuclear plants, because they require the grid to operate their safety systems. They have diesel generators, but once those are turned on, the reactor is scrammed from what I understand. So, in order to shut down the grid, you are going to have to have a coordinated power down otherwise someone is going to burn something out. Not sure how long that will take. You would also have to make sure everyone that relied on electricity (i.e. hospitals, people on ventilators, etc. ) are taken care of. You _will not_ have the benefit of satellite or HF communication during and after the event, so gonna have to fall back to the "sneaker net".

Regarding the transformers (maybe it's been mentioned here) but from my understanding the worldwide production is 35 to 70 transformers A YEAR. There are 100,000's of these larger transformers in the world. From my understanding (I didn't look today), we do not have any domestic (U.S.) production of these transformers. We'll have to buy them, or take them my force, from somebody else. Not even sure that will work with our 60Hz, 120VAC system. Doesn't everyone else have 220VAC, 70Hz or something?