Solar flares do NOT affect the devices on the ground. All the fast-moving charged particles are completely absorbed in the upper atmosphere. And to give you some perspective, the most energetic flares can produce 10^-3 W/m^2 flux at the Earth's orbit.
The flares do affect the geomagnetic field. And a changing magnetic field induces current, but it becomes non-negligible only for very long conductors. So long-distance power transmission lines might suddenly become biased with a persistent DC voltage, and some long optical cables might start experiencing over/undervoltage problems with amplifiers.
But locally? You won't see anything unusual.
All modern telecommunications are over fibre or radio links.
Power lines might be the most vulnerable part, actually. The geomagnetic field can induce current that will bias the core of transformers, causing them to overheat. This can lead to blackouts if the networks are close to capacity, and it's suspected that the 2003 North East Blackout was at least partially caused by them.
Essentially, components that kick in when a voltage exceeds a certain limit to allow that excess voltage to shunt to ground instead of continue to build up in the circuit.
Similar devices in pneumatics or hydraulics are pressure relief valves [https://en.m.wikipedia.org/wiki/Relief_valve], and they provide similar functionality - giving a easier/lower resistance path for the high voltage/pressure, so delicate things downstream don’t fail.
I have no idea what the correlation is between particle flux (the metric reported here) and actual geomagnetic variation which induces the current (varying magnetic field causes voltage). Basically the charged particles zoom past earth, then loop back from the magnetotail towards the poles. The magnetohydrodynamics cause effects large enough to modulate the magnetic field on earths surface.
”We have this long conducting loop” is the issue. The Earth is one component of the loop.
Not necessarily?
https://en.wikipedia.org/wiki/Single-event_upset
Some Miyake events are also thought have lasted a year or longer. I think there could be a very bad time if an event like this lasted a year?
What solar flares do, they deform the Earth's magnetic field so that more cosmic rays (from outside the Solar System) can reach the surface. But the cosmic ray flux is not that high to begin with. And electronic devices certainly won't self-destruct if the radiation is slightly higher than normal.
After all, you experience far more cosmic ray radiation when you're flying on an airplane than during one of these events!
https://assets.lloyds.com/assets/pdf-solar-storm-risk-to-the...
An X-class flare won't do anything. But in the size of the article? Localised temporary blackouts would be entirely unsurprising.
They actually are. Protection against lightning strikes and atmospheric electricity is a part of the design for the high-voltage lines.
CMEs might cause enough additional load on the lines to cause them to trip if they are close to failure already, and this is well-recognized and can be mitigated by load-shedding early.