Feds Have a Plan For Catastrophic Solar Flares (digitaljournal.com)
New submitter Steve Sacco, referencing the newly released National Space Weather Strategy and the National Space Weather Action Plan, written in anticipation of large-scale disruptions from a solar flare or similar event, writes: Released on October 28, 2015, the White House plan involves the coordination of agencies from the federal level, state level, and including emergency managers, academia, the media, the insurance industry, nonprofit organizations and the private sector, all in preparation for the worst-case scenario possible, such as the Carrington Event that took place in 1859.
From what I understand there is really only one preparation, which is the entire reason the Space Weather Prediction Center was created. To know that it's coming and be ready to shut down the grid. This isn't an EMP, it won't overly effect individual electrical systems (like a Hospital running on a generator). It really only effects large networks which have enough surface area to serve as a receiver for the energy of the storm. The biggest threat is operators not reacting fast enough, which would cause the grid voltage to increase to levels that it wasn't designed for which would cause transformers, generators and other control/generation systems to burn out. If that happened replacement of the burnt out systems would take years.