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

[Peter Gutmann]

Harald Hanche-Olsen <hanche at runbox.no> writes:

>an engineer I talked to at the time told me that nobody really knows how to
>restart the grid if it crashes. Or more precisely, it has never been tried.

It's the same with water-moderated reactors, the cooling system of last
resort, the high-pressure injection system (HPI), has never been tested in a
real-world situation, and no-one actually wants to risk testing it.  In brief
(very brief), what it does in case of a loss of coolant accident (LOCA) and
when everything else has failed is inject cold water into the core.  So you've
got a core (and reactor components) at 1000+ degrees, inside a radiation-
embrittled reactor vessel (also at high temperature), and you're going to push
cold water (which is also a neutron moderator, so it increases reactivity)
into it.  It's only really been sort-of done twice, once at Three Mile Island
on a relatively new (non-embrittled) reactor vessel where it only ran very
briefly due to various other issues, and at Fukushima (a much older reactor),
where an operator shut it down fairly quickly, presumably because they'd
decided that the risk of running it was far higher than not running it.

(That's a very brief version, I can also do a three-hour one if required :-).

Peter.