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Comment: Re:The failure mode is transformer core saturation (Score 2) 74

by Ungrounded Lightning (#47537135) Attached to: The Truth About Solar Storms

... the induced DC from a solar storm isn't as instantaneous as a lightning strike. It takes minutes to develop, which leaves time to disconnect the lines and affected transformers if they are properly monitored.

But ARE they monitored for DC? It's not a usual problem.

Warnings on the order of minutes might be useful if the transmission line were the only one invoved. Unfortunately, the power grid is a GRID. Lots of multiple, parallel, transmission lines, and many, many, more going elsewhere and often creating loops.

Redundancy is a good thing in most situations. But when you have to drop a high line, and don't drop all the others simultaneously, you shift the load onto those that are still connected. When you're cutting off because you're near the limit - either due to heavy load at the time or because of the DC issue - you can drive the others beyond their limits (or throw things out of sync and add a bunch of "reactive current" to the load) and create a cascading failure. (Indeed, this is how the first Great Northeast Blackout occurred: Three of a set of four high-lines crossing the St. Lawrence Seaway near Niagra tripped out, and the redistributed load put one after another generator above its limits, blowing its protective breakers and making it progressively harder on those remaining.)

Gracefully shutting down the grid is not something you do on a couple minutes' notice, even if you have a plan in place.

As I understand, the induced DC is something on the order of hundreds of volts, which is much less than the tens of thousands of volts transmitted across ordinary high voltage transmission lines; disconnecting them should not result in arcing problems across the switches.

First, the problem with the induced near-DC is not the voltage, but the current. Transformers and transmission lines have as little resistance as possible, because it's pure loss of valuable energy. The magnetizing alternating current (i.e. the part of the AC that's there all the time, not just when there's a load) is also limited by the inductance of the transformers, but that doesn't impede the direct current at all. A couple hundred "DC" (very low frequency - fractional cycle per minute) volts, induced for minutes around the loop, can drive a hysterical amount of current.

Once the transformer is saturated, most of the damage comes, not from the direct current, but from the line power, which ends up dissipating lots of energy in the transformer. Meanwhile, at these voltages and currents, the switches that interrupt the AC are largely dependent on the momentary off time as the cycle reverses to quench the arc. If, say, the event happened when the line was running at about half its rated load, the direct current will be higher than the alternating current, so there will be no off time. This can keep the current flowing even through an open breaker (while dissipating megawats IN the breaker). Interrupting DC is MUCH harder than interrupting AC.

Heck, at these voltages even interrupting AC is hard. (The video is of an interrupter where the jet of arc-suppressing gas failed for one leg.)

Comment: The failure mode is transformer core saturation. (Score 5, Informative) 74

by Ungrounded Lightning (#47536253) Attached to: The Truth About Solar Storms

High induced votlages in open wires are a problem, but they're not the big one.

The biggie is common-mode currents in long high-voltage transmission lines adding a strong DC component to the current in the substation transformer windings - high enough that when the same-direction peak of the AC's cycle adds to it, the core saturates. Then the inductance of the transformer drops to the air-core value and no longer substantially impeeds the current.

The current skyrockets. The resistive heating of the windings (and the force on the wires from the magnetic fields) goes up with the SQUARE of the current. The windings quickly soften, distort, form shorted turns, melt, open, short out to the frame, etc. The transformer is destroyed, or committed to a self-destructive progressive failure, in just a handful of such cycles - too fast for the circuit breakers to save them (even if they DO manage to extinguish the arcs with the substantial DC component to the current.) Even if the transformer doesn't explode and throw molten metal, gigawatt sustained arcs, and burning oil (or burning-hot oil replacement) all over the substation area, it's still dead.

This happens to MANY of the giant transformers in the power grid. Each set of three transformers that has one or more failed members means a high-voltage transmission line that is shut down until the transformer is replaced.

There are essentially no spares - these are built to order. Building one takes weeks, and there are few "production lines" so little parallelism is available. What is destroyed overnight will take years to replace, while each intercity power transmission line is not functioning until the transformers at its end ARE replaced.

The current occurs because the transformers are organized in a "Y" arrangement, and the center of the Y is grounded at each end (to prevent OTHER problems). The transformers have enough extra current handling capacity to avoid saturation from the DC through that center connection to/from ground from ordinary electrical and solar storms - just not a giant one like we get every couple centuries.

The solution is to put a resistor in that ground connection, to limit the DC in the lines (and dissipate the energy it represents). Indeed, a few lines have such resistors already.

But a suitable resistor is a box about the size of one of the transformers. It's very expensive. And it only makes a substantial difference to the operation of the lines in such a once-in-centuries event. So most executives don't spend the money (and get dinged for costing the company millions) to put them in, to prevent a failure mode that hasn't happened in the generations since Tesla and Westinghouse invented the three-phase long-line power grid.

Or at least they don't until the regulators or their stockholders require it. Which means said decision-makers need a little educational push to decide it's worth the cost and get it done.

Thus articles like this. B-)

Comment: Presbyopia (Score 1) 526

by Ungrounded Lightning (#47525653) Attached to: Laser Eye Surgery, Revisited 10 Years Later

I'm up around retirement age. My eyes don't chage focus much at all. So I have to swap lenses to go from distance to close-up vision. (Yes I could use some kind of bi/tri/progressive-focal lenses. But at the moment swapping is adequate for me.)

Until they find a way to correct presbyopia (and they don't see to be even researching it), I'd still have to don/remove glasses anyhow. With my extreme astigmatism, extreme nearsightedness, and substantial age, I'm not a good candidate for lasic and stand a substantial chance of visual artifacts from it. I'm also a target shooter, so my glasses double as eye protection.

Given all this, the potential benefits for me would be small and the risks and cost oughtweigh them.

But if they ever find a way to fix presbyopia the equation could change substantially.

Comment: Re:Crazy (Score 1) 777

by drsmithy (#47506251) Attached to: States That Raised Minimum Wage See No Slow-Down In Job Growth

Not necessarily (think about it!), but in any event, it is far from clear that minimum wage actually gives more people more money.

Counter examples (actual, real-life, counter-examples supported by data) would be interesting to read.

You can, of course, add the money received by those people who benefit from the minimum wage laws to the total money available to spend. However, businesses pass increased costs on to consumers, or go out of business.

Or they could, shock, horror, take less in profit.

In effect, people's net purchasing power goes down. Instead of helping the people you want to help, you end up hurting them.

Purchasing power isn't going down because labour is getting more expensive, it's going down because labour is steadily getting paid less and less because capital is taking more and more.

The only place the continual downward pressure on wages ends is a tiny proportion of wealthy people who own everything and a huge proportion of people of subsistence incomes. When hardly anyone has any disposable income, where do you think economic activity is going to happen ?

Thus, merely "increasing" economic activity is not a valid goal: to be beneficial to society the economic activity has to be healthy activity, not the production of shoddy products. This can only be the case if we don't cause a net reduction in people's buying power (which is what minimum wage laws tend to do).

Again, evidence to support this claim would be useful.

In reality, countries with higher incomes at the lower-end, rather than the rock-bottom incomes you are advocating, are the countries that have the higher quality goods you are insisting they will not.

No this is done by welfare laws (of which there are a plethora).

No, welfare is there as a safety net for people who are unable to work. Since neoliberalism took over the western world and maintaining a certain level of unemployment became a policy goal (to reduce worker bargaining power and suppress their wages), it has become a necessity for millions of people ready, able and willing to work but who cannot find anyone to work for.

What you are talking about is a universal basic income, which would need to be set at a similar level to minimum wage to meet that objective.

Comment: Re:Crazy (Score 1) 777

by drsmithy (#47504961) Attached to: States That Raised Minimum Wage See No Slow-Down In Job Growth

I never gave my opinion on the matter.

Yes, you did. Your opinion was:

"So lets pass a law that says every person should be paid $50,000 per hour. Economic activity ought to be AMAZING then!"

Which, while obvious hyperbole, is meant to somehow refute the original point by taking it to an extreme never suggested or implied.

Your ignorant political stereotypes led you to make assumptions about what things I never even commented on.

I didn't make an assumption about anything. Your following comment called people who couldn't find work "parasites".

Comment: Re:Crazy (Score 1) 777

by drsmithy (#47504081) Attached to: States That Raised Minimum Wage See No Slow-Down In Job Growth

just because you are economically illiterate doesn't make something "a lie".

You argue the service "can no longer be provided".

That is a lie. It *can* be provided. It's just that customers clearly don't value it enough to make providing it worth the cost.

if it could and it were economically advantageous for companies to provide it, they would have done it.

Yes. I believe that was my point. It's not sufficiently "economically advantageous" to cover its cost.

Nobody had to force the gas stations in the past to provide the service, it was in their best interest to do it because it attracted more customers and there was a competitive pressure to do it.

I'm not quite sure what your point is with this straw man. No-one said anything about anyone being forced to provide full service in the past.

that's the propaganda line, sure. The reality is of-course completely different. The wages of the workers have been destroyed by inflation, not by 'corporate profits'.

Ratio of labour to capital share of GDP says otherwise. Nearly all the benefits of productivity increases over the last few decades have been siphoned to the top 10%, and especially the top 1%. Workers have been getting shafted as their bargaining power has been progressively destroyed by removal of their legal protections and the sadistic philosophy of NAIRU (to say nothing of the ever-increasing "rights" of corporate entities). Meanwhile, the taxes that are supposed to discourage the inevitable greed, selfishness and hoarding of the wealthy and recover some of their waste into productive endeavour, have been completely gutted.

That's before even talking about the mind-boggling explosion in private debt that has been taken up by households in an effort to maintain increasing living standards in the face of stagnant or declining incomes. Encouraged by banks and the wealthy, of course, because people madly paddling the canoe rarely have time to rock it.

It is a pattern that has repeated across the entire Anglo world for decades, it is the aftermath of Thatcherism, Reaganism, and whoever-your-local-neoliberal-psychopath-copying-them-was-ism. Every country has had one, and the outcomes have been the same in all of them - reduced unionism, reduced workers rights, increasing unemployment (because of the previous two events), dramatically decreasing taxes (primarily for the wealth), privatisation of public assets, decaying public infrastructure, decreasing public services, decreasing welfare, decreasing social mobility, increasing income inequality, etc, etc.

What's astounding (well, not really) is that after 30 years of this disaster, most politicians and a sizeable chunk of economists argue the problem is we're not doing it enough !

The world is heading towards a new fuedalism, where the serfs are kept in their place not by threat of arms, but by barely adequate incomes and oppressive debt. It's a Libertarian wet dream - all the slave labour they want to make the rich richer, while maintaining a facade of voluntary participation from the victims since no (overt) physical coercion is involved.

The inflation is created by the Federal reserve bank of America buying up bad USA debt from the Treasury (and the rest of the market) for decades following Nixon's default on the US dollar in 1971.

The core problem in the money supply isn't inflation, it's usury.

Comment: Re:Crazy (Score 1) 777

by drsmithy (#47503863) Attached to: States That Raised Minimum Wage See No Slow-Down In Job Growth

I don't think you know what that fallacy actually means. Nothing I wrote is even close to an excluded middle fallacy.

Really ? You don't think there's any possibilities between no minimum wage and a $50k/hr minimum wage ?

Call it a slippery slope fallacy if it makes you feel any better, it doesn't make your argument any less wrong.

Hurr, durr, ad-hominem fallacy!

You clearly believe the absurd rhetoric that people choose to be unemployed "because welfare!", then you launch off onto another straw man fallacy.

Like I said, mindless tripe. Unthinking regurgitation of conservative articles of faith.

Comment: Re:Crazy (Score 1) 777

by drsmithy (#47498163) Attached to: States That Raised Minimum Wage See No Slow-Down In Job Growth

Minimum wage is an arbitrary price control, a wage is just a price on labour.

To an economist or a mathematician, maybe.

In reality, a wage is what people use to live. It is in no way the same thing as something like the cost of a beer.

If somebody is willing to buy a service at 5 bucks but not at 10 for example, then your statement reads like so: because of politics you should have to pay 10 bucks for the service and if you cannot afford it - tough.

Actually it reads: "you have to pay 10 bucks for this service so it can be delivered while meeting the basic requirements for civilised society".

You could make the same argument about anything that increases costs, from worker safety standards to regulations against lead paint.

Though as a Libertarian I'm sure you think employers should be able to endanger their employees and customers at will so long as it increases their profits.

Comment: Re:Crazy (Score 1) 777

by drsmithy (#47498159) Attached to: States That Raised Minimum Wage See No Slow-Down In Job Growth

Free market capitalist system does not reward companies for maiming people, [...]

It does if there's money in it. Or, at least, it would if it wasn't already illegal.

[...] governments on the other hand force you to participate, if you do not like it, you can always opt out to go to jail for tax evasion.

Or not earn enough to be taxed. Or leave the country.

Setting up minimum wage destroys opportunities for people with no skill sets, that's all it does, it doesn't provide anybody with "decent living" and it shouldn't.

Yes, it should. That's the whole reason it exists.

A minimum wage job shouldn't require any skills. It should be the going rate for unskilled, inexperienced, basic labour.

If it's not, it's not because the minimum wage is too low, it's because the business model is broken.

Decent living is provided by better jobs, but you have to find those better jobs in the first place and if you can never get a job to improve your skills, a low wage paying job, you are much less likely to find the next job that actually pays much more than a minimum wage does anyway.

What skills will someone learn in an unskilled below-minimum wage job, that will help them get a similarly unskilled, but marginally better paid, slightly-above-minimum wage job ?

Comment: Re:Crazy (Score 1) 777

by drsmithy (#47497519) Attached to: States That Raised Minimum Wage See No Slow-Down In Job Growth

Yeah, let's print some and give it away to people. That will sure boost the economy, at least according to your idiotic theory.

It would if it were going to real people and not banks and (by proxy) businesses and the wealthy.

(Which is not, of course, either condoning or advocating unlimited money printing.)

The economy is depressed because everyone who isn't rich, is unemployed, broke and/or weighed down by debt. And the rich don't spend proportionally as much as they own and earn, and certainly not across as much of the economy.

Comment: Re:cause and/or those responsible (Score 0) 667

by jd (#47497503) Attached to: Russian Government Edits Wikipedia On Flight MH17

Nothing is objectively known about the airliner. Everything, from Ukrainian air traffic control ordering the plane to descend to a dangerous altitude to who detected what, is all supposition and hearsay at this point.

It is my personal suspicion that the Ukrainian authorities were hoping for an accident of this sort and were intent on placing a civilian airliner in as dangerous a position as possible. Whether that was the case for this specific airliner on this specific flight is unclear.

And I'd argue that Korean Airlines 007 is a better example for this reason. The US had been using civilian airliners for spying on Russia for some time and doctored the evidence to remove Russian pilots radioing warnings to the aircraft in order to make the incident more incriminating than it was. Whether that flight was used for spying, was shadowed by such an aircraft, or merely happened to be in the wrong place at the wrong time, all becomes incidental. The accident was inevitable and the US government of the time was guilty of ensuring civilians would someday die for the benefit of military intelligence. It was merely a matter of which plane would be blown out of the sky and when.

In this case, the Ukranian authorities deliberately downplayed the risk of missile attacks on overflying aircraft and deliberately worked to place aircraft in the most dangerous air corridors that the airlines would permit. That is indisputable. Their opponents were known to be firing on aircraft and had shot several down. When your time to respond is measured in milliseconds, the nearest aircraft identification guide is mere hours away, to paraphrase what Americans often say about cops.

An accident was inevitable. The separatists weren't interested in avoiding one, the Ukrainian authorities certainly weren't. It was merely who would die for someone else's ideals. Whether or not this aircraft was deliberately placed in the path of a SAM battery is unimportant.

Both sides are therefore guilty. Both sides deserve blame.

"If truth is beauty, how come no one has their hair done in the library?" -- Lily Tomlin

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