Grid woes

I took a long break from the nyah-nyahing over the Texas grid failure in February. Today's WSJ carries a fascinating piece about the vulnerability of the "black start" capacity of the grid, which not only sends chills down my spine about how bad things could have gotten if ERCOT had delayed even a few more minutes before cutting off a huge fraction of Texas customers in the middle of the night, but also explains more than I'd read before about what happens if a grid shuts completely down and has to start back up. The article is behind the usual paywall, but you can get there by Googling.

How is it that we keep reading about these disasters in which the back-up systems turn out to be vulnerable to the same conditions that cause us to need a back-up?  I call that anti-resilience.

When a grid has rolling blackouts or even partial long-term service interruptions, a crucial core of the grid stays active. "Crucial" means not only things we'd really rather not shut down, like hospitals, but the power plants themselves. Power plants shut down not only because they can't get fuel and electric power, but also because a grid with too low a frequency can damage their workings.  Lack of fuel is a temporary problem, but disconnection from the grid or staying on a low-frequency grid are long-term bad news:  a damaged plant will take time to repair, and restarting a plant and reconnecting it to a dead grid is tricky.

I guess I always assumed that a power plant generated its own internal power as a matter of course, but apparently that's not so. If the grid shuts down, or even the part of the grid that's attached to the power plant, the power plant doesn't hum along on its own power.  It can't:  the power has to go to a load.  So when the local grid area shuts down, the plant shuts down, too.  It needs a special "black start" local generating unit to get it going again.

Even if all the black-start units operate perfectly, it's a wildly delicate operation to start the whole grid up again from scratch. If 1/2 or 3/4 of the grid is down, it's easier to add new sections gradually, though no picnic, with delicate attention to balancing the new power and the new load it can serve. When the whole grid goes down, it can take anything from days to the unthinkable months to black-start it.

In this case, ERCOT didn't have to do a black-start, which is a good thing, because about half of our black-start resources evidently were iffy. If they're to be reliable at all, they need a large standby fuel source. Gas that's got to come through vulnerable pipelines won't cut it. Nuclear is nice, as is hydro; failing those, giant oil or gas tanks would be good, or huge mountains of coal. The just-in-time inventory style has made those less common, and we're not giving power generators the right financial incentives to keep large expensive emergency fuel inventories handy.

This issue came up when ERCOT had a near-miss emergency in 2011. Predictably, we addressed the issue by ordaining committees to study the issue and work together to improve yada yada, the usual word salad. We won't have an actual solution until we figure out what it costs to have reliable standby power and reach a consensus on how to pay for it with real money from real electric power customers who have decided it's worth the price.  What I'm reading is arguments about whether the free market or regulation is the panacea.  The Texas system, while somewhat less regulated than some others, is hardly a free market, though it has a strong emphasis on market signals in some areas, generally in an attempt to force efficiency and keep prices down.  Nevertheless, it's not all about efficiency, unless you include adequate backup resources for extreme emergencies in the concept of efficiency.  Extra security costs money.  We're going to have to get past the thinking that either a market or a regulation can change the cold equation telling us that something valuable has to be paid for by someone.  "Someone" is going to be be (1) users or (2) people donating to users.

4 comments:

  1. This is one of those issues that is going to bite us one of these days. Everyone who studies it knows that we need to harden the grid against natural events like sunstorms, not to mention the possibility of intentional damage. Yet somehow it never happens, even though some of the steps necessary aren't that expensive (e.g. Faraday cages). As the guy says in the article, some of these facilities should be the most secure things in the country.

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  2. This is one of those issues that is going to bite us one of these days.

    It's already begun: Colonial Pipeline. And State and/or Network Entities are going to be far more common biters than anything natural.

    100-year weather events are roughly precisely [sic] that, even though they may tend to cluster. The human actors are much more frequent.

    None of which excuses the failures of Texas' grid backups and backup backups. That could have been vastly mitigated if not obviated altogether without government intervention or commission yakking: all it would have taken was unannounced (or announced) testing of the systems. The sort of thing we did (or used to do) both of in the Air Force. The sort of thing this Test Director (and others like me in other companies) did as a matter of course.

    Everyone who studies it knows that we need to harden the grid against natural events like sunstorms, not to mention the possibility of intentional damage.

    This bit is especially irritating. It's breathtakingly cheap and easy to harden our electronic systems against EMP, whether natural or man-made. Advance warning always helps, but even in localized EMP terrorist attacks with little to no warning, the hardening works.

    Eric Hines

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  3. Anonymous4:42 PM

    People falling into the trap of assuming that "global warming" means that winters will always be milder did not help at all. If you look at the records we have from the Roman and Medieval warm periods, when it was warmer than today, they still had cold waves and bad years (especially the eastern Med). But that requires studying long-duration climate patterns, not just hopping onto the latest data fad.

    Don't get me started on wind and solar as large-scale power sources. Grim doesn't like us turning the comments-section blue with the sorts of words that I am inclined to use.

    LittleRed1

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  4. Potentially worse than the Black Start problem: there seem to be increasing interdependencies between the electrical system and the natural gas pipeline system. Whereas traditionally the pumps that drive gas thru the pipeline were operated by gas engines or turbines, which took their fuel from that very same pipeline, there has been a movement to replace these pumps with electric pumps, which are quieter and less-polluting. But if the grid goes out, then those pumps go out, and then guess what happens to the supply of gas to gas-fired power plants....

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