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by eldaisfish284 days ago |
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upvoteby 0_____0284 days ago|
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The proximal cause was a race condition in a piece of software, so as usual it comes back to you keyboard ticklers!
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upvoteby pavel_lishin284 days ago|
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> keyboard ticklers

I hate this term, and look forward to using it all the time.

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upvoteby mikepurvis284 days ago|
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I think the point is that neither of those events should take out a whole city; the design is such that there is considerable redundancy in the system.
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upvoteby Matthyze284 days ago|
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Indeed. For instance, power grids ideally operate with N-1/N+1 redundancy, i.e., the disablement of any single power line should not cause a cascading failure.
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upvoteby conductr284 days ago|
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Relying on vegetation management along millions(?) of miles of lines is the definition of thinking you're in control without even knowing what risks exist. I see this every year in Texas, they trim back trees thinking they have solved the problem - except - they are allowed to trim them back I think 6-8 feet from the lines, ignoring the fact the trees are 20-40 feet taller than the lines. Nobody seems to see the risk that they left there but it's quite obvious to me, we're not eliminating risks at all. We're minimizing them at best, and even then the labor required to trim all the branches around lines every year is impossible to keep up with from an economic feasibility standpoint.
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upvoteby applied_heat284 days ago|
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They trim back what poses the highest risk with the budget they have.

As you have identified A wider right of way costs more.

Usually for lines above some voltage, perhaps 200kV, the cost of an outage due to a tree strike outweighs the cost of additional vegetation management so they will clear the right of way wide enough that no tree can fall and hit the power line.

Around here for 130kV the right of way is still as narrow as it can be and we annually take down the riskiest trees as this is the best for our budget, which is not unlimited.

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upvoteby genewitch284 days ago|
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Concur, they have huge fire breaks they put high tension lines in, where the easement is easily 100' to either side of the lines. This is in Louisiana. When there's a hurricane these lines still break, but not because of trees. During heavy storms, smaller trees hit smaller (480? Some KV?) Lines that go along highways to residences. A high tension line down means a few days without power (about 3-4), a tree on a lower voltage line is usually fixed within hours.

They go through and remove damaged trees near the easements of the highway lines, as well as branches that could break into lines.

As an aside we lived on the same section of grid as the sheriff, and our power was rock solid for a few years, then he left office and now our power is better than average (at least better than our neighbors who's power line cones from the other direction).

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upvoteby quickthrowman284 days ago|
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> During heavy storms, smaller trees hit smaller (480? Some KV?)

Residential distribution voltage varies by utility but it’s usually in the medium voltage range, 5kV to 35kV, with 13.8kV being common.

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upvoteby ExoticPearTree283 days ago|
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Where I live, there are no trees in the path of high-voltage (400KV) transmission lines. Everything is cleared below them and the voltage lines are about 90-120ft high so even if some trees grow, they will not touch the lines.
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upvoteby spongebobstoes284 days ago|
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It seems like both are a monitoring problem and both have a maintenance fix. A tree falling is more forgivable though.
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upvoteby vel0city284 days ago|
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Both of these are operator error issues.
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