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Comment by epistasis | Hacker News Reader

> “I will tell you as an engineer, with training in operations and planning, if you had asked me 10 years ago if we would have been able to reliably accommodate even half of that, I would have said no. Period. End of discussion,” he said.

This has been the story of renewables since the beginning: highly trained people bringing up technical concerns that seem like impossibilities, and then that impossibility being proven to be possible.

I almost never believe a hardened, experienced, smart energy person anymore when they say something isn't possible, because what they really mean is "nobody has done that before."

Up until 2000, nobody having done something before probably meant it wasn't possible: thermal steam turbines have been optimized out the wazoo for decades upon decades.

As we move away from thermal steam production of electricity, we will need to re-evaluate everything, something the energy sector hasn't done for a very long time.

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One of the things not mentioned here is that increasing use of wind and solar is forcing grid operators to make compromises in the traditional standards of how they run the grid. For example, IIRC the ability to maintain a rock-solid 60Hz power frequency has largely gone out the window. In the past this was considered critical for maintaining the stability of the grid and the various equipment that is plugged into it, but now maybe not so much.

Also, as I understand it the various control systems which used to kick in just on occasion and take somewhat heroic measures in order to maintain grid stability are now having to do that constantly. This isn't the exception anymore but rather the rule, in other words, so it's probably not so much a matter of "The system is working well" as it is "We're making it work as best we can, at least for now". This is an important distinction because while in the past an outage or a hack or whatever would have probably had limited scope, today the same might end up bringing a much larger part of the grid down.

One reason for the rock-solid requirement was that over time instead of just power the grid became a distributed time-base. After discouraging that kind of practice the grid operators found they had more freedom. Examples of such use: record players and various clocks running on grid power would use the frequency stability to drive synchronous motors.

Interesting. Naive question: does that mean audiophiles with vintage gear have to rely on custom power setups to get their old stuff to play correctly?

Depend on how vintage the gear is. After '70's when quartz crystals became the norm for everything involving hertz? No need to worry. Before that? Yeah, pretty much

This stuff was usually easily adjustable, so you could compensate for various irregularities. But some turntables had built-in strobe lights for aiding in adjustments, so if the line frequency was off then the strobe would be off and then your adjustments would be off, too. And even if generally well-adjusted, should the line frequency vary too much while playing a record then you would probably notice that. During musical passages it would probably definitely be noticeable, while during singing and speech maybe not at all.

Most audiophile gear from back in the day used DC motors or AC motors with multiple phases driven from on-board oscillators and advertised that fact. Consumer stuff tended to use synchronous motors. But even relatively high end stuff (Thorens TD 160 for instance) would use net-synchronous motors.

Vintage gear has interesting challenges, such as finding good drive belts, they tend to turn to sticky mush after a couple of decades.

Yes, that was exactly the kind of thing I had in mind. Old-fashioned TVs depended on this, too, IIRC, and probably a lot of other stuff. (Newer TVs might still depend on it, for all I know. I haven't really looked into the matter.)

As I recall, the original goal was to try and maintain a solid 60Hz at all times. Then that was relaxed to trying to maintain an average of 60Hz over a 24-hour period. And I think that requirement has now mostly gone away, too, which is a good thing because with so many renewables in the mix these days you probably can't really do it anyway. But you can't let it slip too far because then you still might run into any number of operational problems.

The largest reason why you want grid frequency stability today is because phase shifts on short notice can cause large parasitic currents within the grid itself. Get it wrong by too much and you end up with circuit breakers tripping and that can cascade into much larger failures.

25 years ago the grid didn't have phasor measurement units, distribution-level sensors, internet-connected SCADA systems, smart meters, demand-side management, or even computers very much. Now all those things are commonplace, and they make the grid much more stable in a world of stochastic supply. (Some of those things also make the grid a lot more vulnerable to black-hat hackers, but that's another subject.)

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