Electricity sabotage: North Carolina Duke Energy Restores Power

https://www.reuters.com/world/us/north-carolina-utility-restores-power-all-customers-after-substation-attack-2022-12-08/?fbclid=IwAR1rBJtAR69Mn3rQ1MIGcxYzgfeuaB9xQqT7Sfazgjof71giPA-0YOn90mM

Rifle fire damages transformers allowing cooling oil to drain and transformers to overheat.

How difficult is the repair? Patch the holes. Refill with oil? Restart?

Large transformers probably custom made with long order time. Not easy to replace unless inventory is on hand.

Need for portable replacements in stock. Better security.

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Not sure how you can have “better security” with tens of thousands of these locations around. Video cameras for after-the-fact investigation maybe, but they’re already surrounded by chain link fencing, barbed wire topping, electronic entry, etc. I s’pose you could build giant walls around them; maybe it will come to that.

(I’m guessing this is ‘disgruntled employee’ rather than ‘protesting drag show’ because the investigator say “they knew exactly what they were doing’, i.e. not just some crazy rednecks firing guns).

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Have a Tyvek-type material (i.e. bullet stopping and/or slowing material) wrapped multiple layers around a cage around each transformer. Top and bottom open to allow cooling. Transformers are usually not near the edges of the substation, so the top and bottom of the transformers would not be exposed to being an easy target.

Armor-piercing rounds could still destroy a transformer but much easier to trace the sale of that ammunition.

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Could be both. A disgruntled employee/former emp. who is also a member of a kook group. Tells his friends at a meeting how easy it would be to shoot up a substation. Hey! That’s a great idea!, they say.

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Used to work for a Northeast utility. When the union guys would get pi$$ed off, the transformers at the substations were always favorite targets.

Nothing new here - move along…
'38Packard

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Video camera to record who was there. Plus detectors to know if a gate is opened or detect activity within the interior. Alert authorities and get there before they leave.

If you can shut down the power, copper thieves might have a field day. You wonder if they are that sophisticated.

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Vacationed in Charlotte, NC recently and was totally turned off at the extensive electrical equipment absolutely everywhere you turned. Was surprising how accessible these things are to anyone walking by.

I confess I don’t know anything about how electricity gets from one place to another, but is it really that necessary to have these monstrosities everywhere? I have never seen anything quite like it. Frankly having these electrical structures vomited all over the area was enough for us to drop Charlotte off of our list of possible places to move to. My first thought on hearing the news was that clearly someone else felt the same way I did about having all this ugliness spread everywhere.

IP

yeah, substations are vital. They drop the voltage down to a safe level for household use. They also feed the electricity into factories and other industrial sites at the correct voltage. America would not be even remotely close to the same without them.

From what I’ve read about this, they got shot up from long range with a rifle, so that type of internal domestic terrorism is extremely hard to stop. And it will get expensive if the power companies gotta start building walls around each substation to keep the nutjobs from going jihadist on the power grid.

Oh well, life in America.

You can’t put a fence around every high voltage line that runs through remote countryside, and those are easy targets too. Kids used to use streetlights to practice with their slingshots. Other than video cameras everywhere, I’m not sure there’s really a foolproof solution to this.

Solar panels on every roof.

The Captain

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Agreed. But lines can be buried. Substations won’t due to cost. However, things will be changing over time. Distributed generation of electricity will eliminate the need for a lot of substations, and thus those “targets of opportunity” will go away.

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“Can be” but with great difficulty. Burying residential power lines increases the cost 4-5 times. Buying high voltage lines is fraught, and increases the cost maybe 10 times.

And it comes with a host of problems. Power lines that large give off heat. Stringing through the air, that’s not a problem. In a conduit underground it is. Just finding an insulating wrap is tough, and harder if there’s no where for the heat to dissipate in a conduit, no matter how big.

Air is an insulator, but the ground, especially if wet or damp is a conductor, so leakage is a big problem. If/when something goes wrong it’s pretty trivial to isolate the issue if the wires are in the air. If they are underground for any distance it’s far more difficult to find where the fault is and to get to it.

And did I mention cost? It’s, like, 1000% higher. Probably necessary in some cases, like running through the tinder dry forests of California. Maybe not so much across the hundreds of thousands of miles of high power lines in the US.

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Burying power lines (not high voltage) means far fewer interruptions due to a wide variety of random incidents (vandalism, wind, hail, auto accidents, and so on).

Can’t comment on high voltage lines because I don’t know. But nobody said they had to be AC lines. DC works, but not sure how well either would be for underground transmission lines.

Our area of residential is all underground, but for years the local splice vault would always fail in the winter as water got into the splices, but lately they’ve been solid, so better methods…

But that’s all relatively low voltage, likely all under 10Kv… Next level up they re attempting, here in California to bury critical runs where they’ve caused fires, but even those are super expensive, and I imagine some high voltage limitations… Any nick or scratches when installing could get real nasty, even underground… I think it’s all a CYA project, smokescreen to maybe keep the lawyers/regulators off their backs…

It’s all so vulnerable, I don’t see any way to prevent dingbats from causing problems, multiple paths for restoration is also costly… There needs to be early detection of the dingbats, not ignore their threats…

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They are caged but I doubt you can hardwall them in. They need to breath and cool in all likelihood.

Also this is one of those things that might happen every few years. The expense of replacing a few components verse major added security systems? Really? Our press keeps pushing for perfect when it is not needed. We need a better attitude about the imperfect.

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Back in 1976 for the Bicentennial, some groups planned to “blow out the candles” by blowing up high tension powerlines. That proved difficult.

Now they know rifle shots at transformers are much easier. This knowledge increases the risk.

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Actually, Tesla and Edison had an argument about DC versus AC. Tesla won, and we have AC power transmission for very, very good reasons. So no, DC does not work for large scale electrical transmission. The biggest reason is with AC it is trivial to use transformers to step-up or step-down voltage. You cannot do that with DC.

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Low voltage power transmission means AC is more effective. However, for high power transmission, DC is better. Which is why I asked. Moving lots of power long distances requires the use of DC in order to be more efficient/effective.

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But…

The flip side is that AC is easier to convert between voltages. Converting DC back to AC to dump it onto the local grid at the receiving end is not a trivial process. It takes a large plant to do this, which means significant expense. That expense is only worth it if the transmission distance is long enough so that the efficiency savings outweigh the cost of the DC-AC conversion plant over its lifetime.

And this is why it is still almost always AC for long voltage long distance. Transformers are a simple reliable way to step voltages!

Modern electronics make ac/dc conversions easy. Wind turbines probably produce dc. Otherwise sequencing ac requires controlling rotation speed. Mechanical governors?