I think it would be hard to damage the electronics since you don’t already have a current going to them, but it can still certainly happen if the EMP is strong enough to overpower the electronics. If it can induce enough current into the electronics it doesn’t matter if they’re powered up or not. That’s my understanding anyway.

Correction we do have test results. Look into a method purposed for police to shut down vehicles. Not road spikes but EMP. At 100,000 volts per meter MOST vehicles were permanently damaged. You will also note that these were NEVER purchased by police departments and deployed. Guess why.

Yep, aluminum foil can definitely make a faraday cage but you have to make sure it’s sealed up everywhere and there isn’t even the smallest of gaps or it’ll be useless. No, a fully sealed Faraday cage does not need to be grounded to work. The electrons will flow around it, not through it.

Well said

High altitude EMP’s are nuclear bombs detonated high enough to not cause any physical ground level damage. But going too high could (worst case) essentially terraform the earth to not let us inhabit it anymore or (best case) cause ground casualties anyway (due to RF burns and shock). 50kV/m was the highest practical ground level intensity the IEC could work out and why they selected that intensity for the tests. There is no EMP “specifically for electronics.” It effects everything

Lightning strikes are generally in the 300-450kV/m range. And even in those short durations, could most definitely kill anyone on the receiving end of it. So if one detonated above us at 1000kV/m ground effect above the center of North America, there would be mass casualties ranging from California to Florida and NY, also in parts of Canada and Mexico. If it didn’t have drastic worldwide effects like radioactive storms, downing almost all satellites, etc. The shear stupidity that would take makes it more improbable than that of a solar storm.

Not to mention detonating a nuclear bomb over another country is deemed the worst act of war by the international community that a country or terrorist organization can do currently, and would get stomped by the rest of the world.

Also many car manufacturers submit their vehicles to EMP testing at nuclear bomb test sites. If they had no intention of improving how their cars survive EMP, they wouldn’t even bother with it. Even though they choose not to publish results. On top of hardening them for lightning strikes, which also have a powerful EMP component to them. See the testing VW does to their modern models with manmade lightning. Others do the same but don’t actively publish results.

In a grid down scenario car choice wouldn’t matter too much because fuel would become scarce quickly. Even alternate fuels like ethanol, alcohol, and cooking oils. In that case a bicycle, tricycle, or horses would be the best option.

And solar storm EMP would cook us alive before it disabled even 20% of cars on the road directly. As it’s mainly the E1 component of an EMP that is the most damaging to cars and portable electronics. Solar storms have a bit of E2, and mostly E3, which only effect things connected to long, long runs of wire and jam radio waves. So it would only effect the grid and radio communications while it’s happening.

How do you ground the faraday cage?
Do I attach a piece of metal to the faraday cage with the other end into the ground?
What happens if there’s no grounding?