[BobL]

I don’t claim to be an expert, but my understanding is that EMPs are like lightening strikes - if you can give the current an easy path to ground, the current will not do much damage. If you trap the huge, induced, currents, on the grid, they will force their way to ground, destroying whatever is in their way - pretty much crippling the country and killing off 90% of our population, based on published studies.

It’s really no different than grounding appliances in your house. If lightening hits, and the current has an easy way to ground (i.e., the earth around your house), the current will avoid the insanely expensive ‘controller cards’ that are now required for your ‘modern’ washing machine to work. But if you don’t provide the easy path to ground, the current will still find it’s way to ground, but that ‘controller card’ of your ‘modern’ washing machine will be toasted as the current now passes through it.

[PA Engineer]

The EMP Commission Report (pdf) does a fairly decent job of explaining the effects. The report discusses the different components of a nuclear pulse. We are also vulnerable to Carrington like events. We have not experienced one (with such severity) since our adoption and dependency on electricity, satellites and communications.

[Cold Heart]

I recently bought one of the last non-electronic cloths washers. Fed regulations say all mfg after Dec 31 must be electronic controls. The washer replaced an expensive electronic washer which died months after the extended warranty. Voltage spikes over the years killed it along with a an electronic water ionizer and numerous LED bulbs.

Save up a few incandescent bulbs in case an EMP fries your LEDs.

[Tolerance Sucks Rocks]

So, all you need is all these giant grounding wires dangling down from the 100kV electrical line pylons, eh?