Hi JoJo;
EMP and a CME/SME are related in that they cause something called the Compton Effect. - for the techno-nerds among us, I'm going to way over-simplify this.
http://en.wikipedia.org/wiki/Coronal_mass_ejectionhttp://en.wikipedia.org/wiki/Compton_scatteringEMP occurs in a range of radio emissions similar to a garden variety microwave or radar. the difference is the transient wave - it can be very powerful - but very quick, in the order of milliseconds.
protecting the power grid is very difficult - all of those long wires act like an antenna collecting all that energy and funneling it into your house (don't expect a surge protector to work with this level of power and voltage). Anything plugged in during this kind of electromagnetic storm will probably cease to function - maybe even catch on fire.
what is a faraday cage - the simplified version - a space protected from electromotive force. Metal will absorb and reflect this type of energy - the idea is to reflect some of the danger and channel the rest away from the protected space within. To use the example of a car - you used - it is a metal box on 4 big insulators. it's a bit like a faraday cage. Cars built today have lots of computers built into them. Computers are rather exposed to damage during an EMP. The car will provide some protection, but it will be spotty. The car may or may not work after an EMP.
the main parts of a faraday cage is something to reflect or re-direct the energy. an insulator. the protected package.
typical types of faraday cages (think surrounded with metal on all sides)
ammo cans, metal cabinets, well sealed metal trashcans with metal lids, old metal desks and filing cabinets (the drawers when they are closed) and the mesh cages.
ok, to use these, make sure they are sealed all the way around. make sure the package is insulated. try and put it in a dry basement or cellar (to avoid EMP line of sight).
OK; The question about solid metal versus chicken wire.
simply put, it depends on the frequency you want to protect the package from. remember the mention about the Compton effect being in the radar frequency range? the energy has a frequency that is mathematically related to its wavelength. OK, the smaller the holes in your shield/mesh/cage material, the smaller wavelengths that can be blocked. if you want maximum protection, you want a solid wall, top - bottom - and all around. it doesn't need to be thick just continuous. so chicken wire (1" mesh) will block frequencies below 11.8 billion hertz or 11.8GHz (ok for most uses). I recommend using 1/4" hardware cloth if you want mesh - a bit more expensive but better protection.
Ok what am I using? a galvanized metal 30 gallon trash can with a tight sealing lid. I line the inside all the way around with cardboard. I use 2" of packing foam (like polystyrene or 2.2lb density shipping foam - saved up from shipping trash) held on with spray on contact glue. put a thick trashbag in the can and put the electronics in individual antistatic bags, seal them and put them in the can. fold the plastic over the top of the load and put the lid on tight. easy to access, easy to check, fairly waterproof and easy to move. Cheap and easy.
I don't know this guy, but the pictures will give you the idea.
http://www.msgunowners.com/t8239-electro-magnetic-pulse-coronal-mass-ejections.
ok the mesh type faraday cage. surround the cage with mesh, you could use a trunk or wall locker or a free standing cage.
put a plastic tub with preps (not emp susceptible) in the bottom of the cage and stack the emp fragile stuff on top (in tubs too if you like) - leave at least 6" to a foot all the way around with no metal inside touching the cage.
also check out this
http://unchainedpreppers.com/forum/general-discussion/emp-and-you/msg1916/#msg1916
