The New Scientist recently posted a nightmare scenario for the destruction of the electric grid. Apparently, a solar incident no worse than something actually observed in 1859 -- the "Carrington event" -- could destroy all the transformers in the US. Or in the world. We don't have close to sufficient spares sitting around. Humankind would be without most of its electricity for a year or two at best. Those of us who depend on manufactured or transported medicine and food in the usual manner would be dead quickly. Depending on how comprehensive the destruction was, life might or might not be knocked back to the level of, say, The Postman, but things would be definitely uncool.

Key steps for preventing such a scenario include:

Beef up space-based early warning (if you shut the system down fast enough it doesn't get destroyed)

Increase the speed at which the system can be shut down (current best-case is around 15 minutes, and these plasma bombardments can happen faster than that -- oops!)

Design the (new) grid to be less vulnerable to cascading failures (obviously tough, since we're adding complexity going forward)

Have lots and lots of standby transformers sitting around (nice use of stimulus money, but will they be wasted as we redesign the grid?)

Less dramatically, CNN reminded us some days ago of the obvious point that the new smart grid could be eminently hackable. (Network World offers more detail here and perhaps also here -- and makes it sound like the problems will NOT be fixed.) In principle, this could cause overloads with consequences as drastic as in the first scenario. Of course, that's extremely far-fetched. The hackers would both have to understand the dependencies of the network better than the network's builders and defenders do, and also find a way to actually exploit them. Or else they'd have to be amazingly lucky. But hey -- to this day, nobody (even whacked-out conspiracy theorists) offers a really clear picture of how and why the World Trade Center towers completely collapsed.