A NERC report issued in February 2012 and now referred to in the Wikipedia entry for “geomagnetic storm” downplays the impact of solar coronal mass ejections on the grid:

According to [an earlier] study by Metatech corporation, a storm with a strength comparative to that of 1921 would destroy more than 300 transformers and leave over 130 million people without power, with a cost totaling several trillion dollars. A massive solar flare could knock out electric power for months. These predictions are contradicted by a NERC report that concludes that a geomagnetic storm would cause temporary grid instability but no widespread destruction of high-voltage transformers. The report points out that the widely quoted Quebec grid collapse was not caused by overheating transformers but by the near-simultaneous tripping of seven relays.

If NERC is right, then our primary concern should not be EMPs caused by the sun, but EMPs caused by high altitude nuclear blasts. So if you trust the good intentions of the leaders of Iran, North Korea, and Pakistan,you can rest easy.