[_Jim]

our grid is immune to a deliberate take down.

Well, "Prove me wrong."

Whoops.

We don't want you doing that - someone will see you and turn you in like this character ...

WHAT I find surprising is, we've got people on this board that couldn't explain how the series circuit in a flashlight works YET they will contend THEY can see scenarios where 'the grid' could be taken down ...

NEITHER have these people done their homework and studied several of of the BIG historical blackouts we have had for ANY idea on the scope of just WHAT it takes to get a REALLY BIG blackout to occur ...

'The grid' JUST like other facets involving machinery/systems (like the phone system) in our lives have TWO things working constantly in their favor: 1) man in the loop overseeing operations and planning for outages and contingencies and 2) a lot of redundancy in most circumstances that allows the system to tolerate portions of 'the grid' to fail both in terms of generation and transmission -

- with this ONE caveat; that #1 works, and it didn't back on August 14th (FirstEnergy's control facility was 'hosed up' for some reason that day and the operators NEVER made any of the required 'right moves' - like load shedding GIVEN the generation available and the lines they had to work with. It also didn't help that deferred 'right of way' tree-trimming came back to haunt them that day and took important lines out of service) ...

[null and void]

Well, when I was studying EE I was told abruptly taking out (grounding) one phase *could* cause a 3ø generator to pound itself to pieces before it could be stopped. I didn't have the guts to try it.

I do know that a determined foe can figure out an unexpected weakness in any system and exploit it.

I do know that power grids can fail accidently, as has been demonstrated in a surprisingly large number of systems across the world in the past few months. Notably most of these outages affected countries that supported our efforts in Iraq. Perhaps this is only because everyone else doesn't have a grid to down?

I suspect a timed sequential takedown of key links could crowd load onto a known weak link that could then be cut, giving the operators a load sheding problem they may not have enough time to gracefully recover from. IIRC something like this happened accidently causing the '73 blackout.

The human in the loop is only as good as the information s/he has. Cutting communications, or more subtly, presenting normal expected data while the crisis builds renders this the weakest link - bu bye!

That the controls of a reactor are prePC does make the system more robust, but one does not need to take down any single generator to fragment the grid.

If people can design and build it, other people can figure it out and destroy it.

BTW, Do you know the differnce between a mechanical engineer and a civil engineer?

[meyer]

- with this ONE caveat; that #1 works, and it didn't back on August 14th (FirstEnergy's control facility was 'hosed up' for some reason that day and the operators NEVER made any of the required 'right moves' - like load shedding GIVEN the generation available and the lines they had to work with. It also didn't help that deferred 'right of way' tree-trimming came back to haunt them that day and took important lines out of service) ...

Actually, #1 and to a lessor extent, #2 both failed, but #2 was a direct result of #1.