Solar [coronal] mass ejections occur most frequently at the peak of the 11 year solar cycle. Statistics show that Earth will get a direct hit from a major solar mass ejection every about every 500 years. This estimate comes from the number of solar mass ejections we see and frequency. Now figure in the size of the Earth versus the size of the solar mass ejection. The calculation is similar to the odds of a pin landing on a particular point on a globe, except Earth is the pin and the globe is the sun. In the end, we can estimate that Earth will get hit every 500 years or so by a flare large enough to affect our electronics.
This doesn’t mean that life will end when the next one hits. Solar storms come in different intensities. The impact of a solar mass ejection our civilization will depend on its strength and the technology we think we need to get by.
Satellites in orbit are the most sensitive when it comes to solar radiation. They lack the protection of Earth’s atmosphere. Those satellites on the side of the Earth that is facing the Sun during a major solar flare would have component failures. However, not all satellites would be lost. There are different designs of satellites, with some more shielded [or "hardened"] than others. Satellites on the back side of Earth couldn’t be affected unless the solar flare and its accompanying radiation showered the Earth for many hours as the satellite’s rotation brought it to the day side. And variations in the Earth’s magnetic field could offer protection to some satellites. We would see a mix of charred, failing and fully functional satellites. We can’t know when a flare will hit except for the likelihood of it occurring during the peak of the solar cycle, so no nation can protect all of its satellites by keeping them on the night side of the Earth.
Your Best Defense Against This
Don’t rely on GPS or Global Positioning Satellite Systems for navigation. Know your route or know how to get there with only paper maps. And never rely on GPS-based geocaching to find hidden supplies in an emergency. If we see a massive release of solar radiation that is the natural equivalent of an Electromagnetic Pulse (EMP) weapon, then your GPS capability will probably be gone.
Long AC Transmission Lines
Safety equipment designed to prevent overloads will protect most of the transformers connected to long Alternating Current or AC power transmission lines. However, some transformers will get overloaded by the field strength of a solar flare or solar storm. The bad news is that this means that utility crews will still have to replace hundreds of transformers in addition to resetting thousands of circuit breakers where the safety equipment prevented the transformer from overloading. This is a slow process, and it is hampered by the fact that we don’t have a huge stockpile of transformers for a disaster of this scale. (Although stockpiling spare transformers has been recommended as a step to minimize the impact of a nuclear weapon or EMP pulse weapon unleashed on the United States.) The task is made more complex by the need to bring thousands of [power plants and] power lines back on line and in [phase] sync to restore the [three] power grids in CONUS]. [JWR Adds: The manufacturing lead times for large transformers are as long as 24 months!]
Power distribution systems would be massively disrupted for anything greater than a mid-scale flare, but the power distribution system would be spotty failures for anything less than mid-scale flares. These failure rates will be affected by any improvements in the overload protection devices that hopefully have been made since the Northeast Blackout of 1965. If the recommended overload protections were put in place and maintained, the size and scope of outages would be reduced.
Your Best Defense Against This
You should know how to disconnect your home from the local power grid as soon as you have warning of imminent power disruptions, [via your main breaker.] At a minimum, have the means on hand to live a few weeks without electricity. It would be better to have renewable power sources or a generator and fuel stores on your property.
The Internet itself will go mostly dark. Why? Imagine what happens if 99% of the servers go off line. They have not all been destroyed. They simply need power to be available. Without the power grids up, the Internet will be crippled.
Many servers will be without power due to the damage to the power grid. Those servers that are still running will be isolated by power outages to the hubs they use to transmit information. A functional server in a computer room is a hub in the Internet. If it cannot connect to the major nodes to relay information then it might as well be turned off. And in an emergency like this, facilities running off of generator-supplied power will focus on properly shutting down rather than keeping extra servers running once they’ve backed up their data.
Fiber optic lines will be okay. However, with the disruption of power in the AC transmission lines, means that the fiber optics will be “dark” until they get power again. Those relying on Skype or Internet access will be left in the dark, since fiber optic lines won’t run without power, and the backup option of Internet via satellite will not be an option.
Your Best Defense Against This
Have other methods of contacting family members, such as [FRS , GMRS, or MURS] walkie-talkies and ham radio. Document everyone’s phone number in a [hard copy] address book, and make multiple copies so that you can find their contact information even if the Internet is essentially dead.
Back up your data locally, regardless of whether or not you perform online backups. Have local sources of any information that you frequently reference. And make sure you have entertainment on hand that does not rely on an Internet connection.
Laptops with batteries are relatively immune to solar flares. They receive power from the battery and so will remain operational until the battery runs out. [If disconnected from outside power or data cables] they will not get fried by a solar flare. However, they could be ruined by an EMP weapon [if in very close proximity]. Desktop computers will be in worse shape. The thousands of miles of power, phone, and Ethernet cables connecting many desktop computers act like long antennas, picking up the voltage generated by the solar mass ejection. The cables connecting the computers thus have the potential to damage desktop computers [or any laptops that are connected.]