Texas Blackouts 1

[lengould]

Anybody have any detailed information? Just heard on CNN about rolling blackouts inititated by the grid manager covering 80% of state. 15 min intervals. Seems afully early in the year.

Pechez les vaches.

 

[lengould]

Dotty Roark (ERCOT). 7:22pm CST, CNN. 1050 pre-agreed interruptible. 1000 mw of firm load. Are a lot of peakers still in winter layup or what?

Pechez les vaches.

 

[electricpete]

I'm pretty sure the blackouts didn't affect 80% of Texas. (I live in Texas and haven't heard of it unit now). A quick search shows the blackouts are limited to ERCOT which is associated with 80% of Texas' power. (but not all of ERCOT has rolling blackouts)

http://www.dfw.com/mld/dfw/news/state/14363574.htm?source=rss&channel=dfw_state

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[lengould]

Ah, that makes sense. CNN wasn't clear of that distinction, though they did mention something about 80% of Texas, now I recall they stated "affected ERCOT area, which manages 80% of grid." They did say the blackouts affected omly/mainly 3 large cities which they named so I should have picked up that that couldn't have been 80% of all Texas.

It may be further poor quality speculation on my part, but isn't this an indication of unusually poor grid operation? Surely Texas must have had equal weather conditions in past years, and should be prepared for this?

Pechez les vaches.

 

[rmw]

Here are a few links pulled from the Drudge report.

http://www.click2houston.com/news/8777649/detail.html

http://www.dfw.com/mld/dfw/news/state/14363574.htm

http://www.news8austin.com/content/your_news/default.asp?ArID=159857

http://www.wacotrib.com/news/conten...wacbrownouts.html?cxtype=rss&cxsvc=7&cxcat=11

Looks like it is going to be a long hot summer.

I, too, wondered where all those idle peakers were. Heck, earlier in the day I was in a plant a couple of states away talking to a plant manager who is trying to sell 16 peakers. But, he couldn't have gotten his excess power into ERCOT anyway.

I live on the ERCOT island now; lucky me, but I am away right now where there are plenty of idle peakers.

rmw

 

[electricpete]

In Texas there is a winter peak and a summer peak, so the generating plants all do their outages in Fall and Spring.

Many of the plants are still in Spring outages. We had 100+ degree heat over a large portion of the state today as I remember from the weather map. That is unusual this early in the year, even down here.

As rmw mentioned, ERCOT is an island in the sense that the ERCOT ac grid is not syncronized to the Eastern or Western grid. So we have limited capability to import power to cope with problems like this (although I can't ever recall talk of rolling blackouts on this scale before). The import capacity is limited by the capacity of the DC links. I think there is one group in East Texas and one in West Texas but they are limited in capacity. There has been talk for awhile of upgrades.

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[wfowfo]

Quote:
"They did say the blackouts affected omly/mainly 3 large cities which they named so I should have picked up that that couldn't have been 80% of all Texas."

Don't bet the ranch. I can guarantee that there were many more areas effected than 3 major cities.

 

[electricpete]

Some more info:

http://news.yahoo.com/s/ap/20060418/ap_on_re_us/power_blackouts_1

"As much as 15 percent of the state's power supply was already off-line for seasonal maintenance to brace for the summer's energy usage peaks. Then four power-generating plants shut down unexpectedly amid the stifling heat, said ERCOT spokesman Paul Wattles."

"Typical usage for Texas in April is about 40,000 megawatts a day, but the state peaked at 52,000 megawatts on Monday, Wattles said"

I assume "megawatts a day" was supposed to mean either peak demand or 24-hour average demand.



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[itsmoked]

The ERCOT users should count their lucky stars they are NOT hooked to the national grid or they'd probably be buying power at 10-30X like the giant California screw up... Every time I pay my bill I wish CA had been smart enough to roll us instead of paying punitive extortionary rates.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[electricpete]

The news reported rolling blackouts in Dallas, Houston, Austin, San Antonio.

Upon coming to work this morning, I heard from some coworkers in the small rural towns of Port Lavaca and Wharton that those towns had blackouts as well.

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[rmw]

Somehow deep in my memory I think I remember once hearing that the DC line that is connected to an Oklahoma utility is good for about 500 MW.

If that is true, and the other one(s) are of similar size, then that is not many drops in a bucket the size of 52,000 MW.

I did drive by the Tenaska plant in Rusk County this AM, one of two that Tenaska has that is placed so that it can put power into ERCOT or SW Power Pool (or whatever grid that they are connected to) and it was cranking wide open based on certain indicators that the trained eye can see from the road.

Why can't we just throw some jumper cables across their switch yard(s) and get ERCOT synchronously connected to the rest of the country?

Did we have any blackouts today? I haven't heard of any yet, but I'm always the last one to know anything.

rmw

 

[electricpete]

Yes, as I remember the East Texas DC tie is the largest and the others are smaller. Just a drop in the bucket.

I'm not sure whether your question about jumpers was half-serious. But I have wondered why we can't establish ac ties. Here is what little I know (beware - speculation).

Texas power system evolved as a separate system originally for political reasons (by declaration of the legislature). Now that it has evolved without interconnections, stability considerations make it impractical to tie the large Texas system into the other large systems using one or two or three medium length ac transmission lines. It would be like trying to tie together two very large masses with a thin rubber band.



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[electricpete]

I think a better way to say it would have been:

"It would be like trying to tie together two very large mass-spring systems with a thin rubber band."

The two systems would act relatively independently except for the one weak tie. Small oscillations in either system would put a large stress on the tie.



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[lengould]

Agreed on AC ties. Too expensive now. What Texans should start supporting now is a large continental DC super-grid. Give Texas a 10 GW dc link west to CA, a 10 GW dc link North to Wyoming (coal), and another 10 GW east into Florida and all the issues go away. It could have been completed nationally in US and Canada for just over $100 bln, a lot less than already spent in Iraq.

Given the supergrid, west Texas could economically exploit it's wind gen potential using hydro gen backup from Northwest and Canada (eg. Quebec has nearly 40 Gw of storage hydro installed which makes superb backup for wind when the wind stops blowing) Many other benefits, eg. saving natural gas for export to northeast home heating while using minemouth IGCC coal-gen power from Wyoming.

Suppose to many business oxen would get gored though.

Pechez les vaches.

 

[wfowfo]

Right of way procurement should be fun on that one.

 

[resqcapt19]

Texas power system evolved as a separate system originally for political reasons (by declaration of the legislature).

Just in keeping with the fact that Texas is "The Lone Star State".
Don

 

[lengould]

Right-of-way should be simplified a lot just by following freeways and railways with extra-tall poles similar to wing generator towers, in fact in good wind areas would make sense to extend the towers another 30 meters and put wind generators on top of them.

Pechez les vaches.

 

[rmw]

I was being half serious and half facetious about jumper cables.

The problem I see, even if such cables are a doable thing is how would you synchronize the two systems to be able to close in the breaker(s)? Can you imagine the size of that synchronizer?

There are plenty of potential tie in points where ERCOT utilities and outside ERCOT utilities have adjacent infrastructure.

The lack of tie in-ability contributed to the aftermath of electrical outages after Hurricanes Katrina and Rita. As it did during the rolling blackouts that are the subject of this thread.

There was lots of spare capacity in Louisiana and Arkansas, and I don't know about other directions (Oklahoma, New Mexico, etc.)

rmw

 

[electricpete]

I googled and I could find some info on the DC ties: Capacities are 600mw in east Texas, 200MW in north Texas (I assume it ends up connected westward) and 35MW in South Texas (connected to Mexico).

But I couldn't find any information on the reason for the dc ties and why Texas can't connect.

In 1996 I took a power transmission system course and my professor said the reason the reason Ercot was separate was stability reasons. He mentioned there was a study of an ac interconnection that would require at least 6 parallel ac lines to form a marginally stable connection.

Lare in 2003 several folks at the plant told me the part about Texas historically having a separate system for political reasons. They were also aware of some study for ac interconnection which was rejected as too expensive.

I kind of put the two stories together to get my story, but I'm not positive it's complete or correct. Wish I could find more on google but I don't see anything. I don't think that syncronizing would be a huge challenge. After all the system operators have fine control of system frequency.

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[Laplacian]

There is another DC interconnect in West Texas around Hobbs, NM. - Seminole, TX. I don't know how big it is though.