[Cryptography] Smart electricity meters can be dangerously insecure, warns expert

[Jerry Leichter]

>> Ross Anderson has written a great deal about this. In his view, I
>> believe the biggest risk is that hackers can crash the grid by turning
>> the meters all off at once, from where it would take the Uk sevveral
>> weeks to recover.
> 
> It's a valid threat.  If someone turned *off* the power of a large
> part of a city, all at once, I think most of the transformers at
> the substations would explode.
Why?  Transformers reflect demand back to the primary side pretty much instantaneously.  Ultimately the components that get stressed by sudden load changes are the generators (and some related compensation components), which may be unable to react quickly because of their huge mechanical inertia.

Lighting strikes dump huge amounts of energy into power systems on a regular basis. Even the largest power lines can get cut and short to ground - rather spectacular events when they occur.  There are also huge surges due to solar bursts hitting the atmosphere.  Power systems are designed to survive this sort of stuff ... up to a certain point.  (If the Earth were to be hit by a large ejection of charge particles - something that happens regularly - the surges would knock out most of the world's power systems for long periods of time.)  But below the point of total failure, the systems are designed exactly to deal with massive fluctuations in supply and demand.  Absent some specific, carefully computed vulnerability (which may well exist, but you'd have to find it and target it), I'm skeptical that just dropping demand drastically would do much more than maybe trip some breakers.

                                                        -- Jerry