I’d like to learn more.
What part of the grid proper would there be any necessity to shield from EMP? Isn’t “the grid” basically a bunch of wire and transformers? What specific “sensitive devices and organizations against electromagnetic pulse and electromagnetic terrorism” would be protected?
The wires mostly, I believe.
When a big nuke goes off at high altitude, it displaces magnetic field lines that surround Earth. This happens very rapidly at first, then settles down over a period of minutes after.
When that big initial transient occurs, the amount of magnetic flux that links some of the long-distance stretches of transmission lines suddenly changes. This induces big voltages and currents in those lines.
There may be other effects in the RF spectrum I’m not aware of.
Also, consider that the grid (like most everything else, nowadays) is controlled by -- computers.
During an EMP, power lines become antennas that channel the EMP pulse. Thus power lines extend the range and effect of an EMP. While the original pulse might be enough to fry a state’s footprint, the power lines extend the area. The pulse can then damage / destroy much of the power distribution network over a large area.
To repair the damage, many lines, junctions, transformers, trip/triggers, etc will need to be replaced. Depending on the time location and possible cascade effect, power plant transformers may need to be replaced and possibly even the power plant generators. That is near to a worse case scenario. Power plant transformers are not sitting on the docks waiting to be shipped. They are multi-ton, ship via train, HUGE transformers. Order to build to delivery can take a year and a half.
Control systems, local and remote, are solid state.