This article was written in 2012 by Boston U. geophysicist Robert M. Schoch. It’s no less true in any way today (although power companies are somewhat better prepared thanks to articles like this one - and they were nervous last week).
Auroras would be much easier to see if it this happened and the lights went out for months. Website:www.robertschoch.com
They don’t talk about it a lot, but. If it looks really bad, I suspect that what the grid operators will do is disconnect and shut down as much of it as possible and wait it out. Better to have no electricity for a week than for hundreds of transformers to be ruined …