.

[NickW + 2,714]

3 minutes ago, turbguy said:

Hydro and GT plants can do that quite well, too.

Coal? Not so fast. 

Nuc? Forget it.  They stay put.

That analogy I use for wind is similar to that of a sailing boat. You can either use all of it or a proportion of it by reefing the sails or by spilling wind. Or none at all by dropping the sails. 

I went on a visit to Dinorwig once which the biggest PS station in the UK (1860GW) that can basically go from 0 to 1860 in under 2 minutes and 1860 to 0 in a similar time. 

Dinorwig Power Station - Wikipedia

Edited February 22, 2021 by NickW

[turbguy + 1,544]

Just now, NickW said:

Doing the EN-RON RON dance? 

I thought about Texas law enforcement being ordered to raid Nat Gas generating units to seize operator logs, sequence of events recorders, data historian recordings and such.

Then I though, "Naw, people aren't THAT mean"!  (I hope).

[NickW + 2,714]

1 minute ago, turbguy said:

I thought about Texas law enforcement being ordered to raid Nat Gas generating units to seize operator logs, sequence of events recorders, data historian recordings and such.

Then I though, "Naw, people aren't THAT mean"!  (I hope).

Here the operators of Hydro can hold back to get a better price but if there is a system need they can be ordered to immediately make all power available. In addition the transmission operator owns about 2.5GW of pump storage so can intervene themselves. 

[Ward Smith + 6,615]

29 minutes ago, turbguy said:

You are not considering DEMAND.  The total of all SOURCES MUST, almost instantaneously, equal DEMAND.   So one source , or many sources, can go up, without any sources going down, to match increasing demand. 

If you LOSE source, you MUST cut demand.   That's called load shedding.  That's called "rotating blackouts".

THAT is how "power works".

The "ditch" you refer to is the transmission and distribution system.   Some parts of that system do have limits to flow, which complicates ERCOT's function.

It's easy to overflow a ditch if you put more water in, but don't take any water out.  It's easy to empty a ditch if you take out more water than you put in.

I stand by my statement.  Did wind source go down during that 2 hour period?  Yup, by about 230 MW (about one CCGT plant).  Did nat gas go down?  Yup, BY about 9300 MW!    WHY??

Umm dude, you're just repeating my power explanation from 20 some pages ago, of course I know supply must equal demand. You've been looking at graphs at 2 AM.  I'm not convinced there's a ton of demand at that time slot, even if it is cold outside. I'd rather see the output of the SCADA system, it would make everything much clearer and the granularity is obviously much much finer.

The issue brought up in the article is that wind isn't being paid for power like every other source, but automagically gets paid for generation, no matter what. That is the fundamental flaw in the system. As with my Washington State example and wind fighting water, they also get paid for generation so happily pay the fines to BPA for ignoring the cease and desist orders from SCADA control. Since wind is the adolescent, the adults in the room need to accommodate, always. When wind is only single digit percentages of the grid it's doable but when 40% of the generated power comes from wind, Houston we have a problem! Wind cratered by 93% and after going balls to the walls for so long, that was a lot to make up. Those CCGT "peakers" aren't designed to A) go full out nor B) go full time. This episode they were called on to do both. 

@nsdp can chime in with his "insider information" but I'm a bit confused as to his pedigree. At times he's claimed to be a lawyer, a Republican committee chair, an oilman and now, apparently a power engineer. I'm curious what he'll claim next. 

This whole discussion about frequency is a red herring. Utilities don't sell "frequency" they sell "power". SCADA monitors frequency because that is the canary in the coal mine for detecting problems. Period. Full. Stop. Certainly there are devices out there that rely on frequency, such as an electric clock and synchronous motors, but even they aren't so precision that a 1/10th of a percent difference is going to break anything. No, the frequency monitoring is strictly to aid the power system because they'll catch that change faster than voltage or current issues. 

[Jan van Eck + 7,558]

9 minutes ago, Ward Smith said:

nsdp can chime in with his "insider information" but I'm a bit confused as to his pedigree. At times he's claimed to be a lawyer, a Republican committee chair, an oilman and now, apparently a power engineer. I'm curious what he'll claim next.

🤣🤣😎

[NickW + 2,714]

4 minutes ago, Ward Smith said:

 

Wind cratered by 93% and after going balls to the walls for so long, that was a lot to make up. Those CCGT "peakers" aren't designed to A) go full out nor B) go full time. This episode they were called on to do both. @nsdp 

?????

Over an 18 - 24 hour period prior to the blackout dropped wind  from 10GW to 5GW . ERCOT had already built in a conservative estimate of 6GW being available from wind in February so CCGT and other operators would have been aware of the high demand call probability. 

Whats 5GW over 18 hours? 

4.6 MW a minute. 

The typical ramp rate on  the gas turbine element alone on a CCGT is 50MW a minute (or more).

 

 

[surrept33 + 609]

10 hours ago, Richard D said:

Arrhenius boasted that he had never done a practical experiment in his life. I was trained in chemistry where it is easy enough to back up theories with practical research. It is more difficult with climate,but not impossible. If it is possible to shine a laser beam at the moon and get a reflection,then why why not shine a carbon dioxide laser at the moon and see how much of the light is really absorbed by atmospheric carbon dioxide? Atmospheric carbon dioxide varies with season,allowing calibration.

Well, to Arrhenius's benefit, he had to do 10000 calculations by hand, whereas, your smartphone can easily do a billion similar calculations every second - this is really a credit to the miniaturization of the transistor, which was long theorized but most of the minitutizing limits seemed to have been hit recently due to heat and yield during manufacturing: https://en.wikipedia.org/wiki/There's_Plenty_of_Room_at_the_Bottom, of course for microscale manufacturing, for example microfluidics are quite interesting because of all the quantum effects, but it is in the realm of what you need for things like predictable regenerative medicine.

In the field of remote sensing, there's been a variety of tests done, both with active sensing (perturb and hear) or passive sensing (by analog, this can be thought of hearing or smelling, one might also thinking about perception works in vivo). this is how LIDAR, RADAR, SONAR, all work, though the wave mechanics and background fields are certainly different. For weather detection, these cheap balloons have been in use for a long time, but really it's the density of them along with better models that have made weather prediction and climate modeling more accurate over the years (you generally need to think about causality to gauge what's "real", versus a statistical/mathematical/computational "trick"😞https://en.wikipedia.org/wiki/Radiosonde 

Now, more modern versions of these sensors do some sort of hyperspectral imaging (see: https://en.wikipedia.org/wiki/Hyperspectral_imaging - a good way to think about these is to imagine your eyes. the retina can send to your visual cortex the visible spectrum from photons, or energy integrals "exciting" your retina cone. with hyperspectral imaging, you can imagine an spider that had eyes that could constantly vary parts of the EM spectrum it was looking at and change fixations of the underlying area to smear out the spatial field being visioned. These come with active sources, like LIDAR or MASAR that were being beamformed usually by some variation of the fourier slice theorem. This type of imaging has been reduced in price by about 100x in the last decade and has the benefits of being able to be guided by modern machine learning techniques, but is still fairly power inefficient. Some companies were working on modular sensor packages with multiple arrays (a constellations, or a big antenna) of balloons (see: https://loon.com/ but the underlying business case just got leapfrogged by SpaceX's success in economically putting massive amounts of satellites directly in low orbit - see https://www.starlink.com/)

NASA is putting this into the ISS most likely next year for their decadal sun/moon-calibrated earth sciences survey: https://clarreo-pathfinder.larc.nasa.gov/ It will perform hyperspectral imaging since it on the ISS, and thus has access to a lot more power, keep in mind that *clouds* and how they absorb/reflect radiation are the biggest source of uncertainty so it's thought that looking at larger portions of the EM spectrum will reduce uncertainty and allow for more precise calibration relative to the dynamics of land use changes (especially since the near/far field can also be reconstructed from the ground as well. hell, with modern day cell and wifi technology, you can "see" those with some fidelity as well, this is what microlocation sensing does). In addition, it will also calibrate with other satellites by doing active broadcasts and comparing "notes" to do further calibration: https://clarreo-pathfinder.larc.nasa.gov/inter-calibration/

With any sufficiently complicated (observational) multi physics problem it's almost always the uncertainty and potential sources of error that people tend to scrutinize. 

Edited February 22, 2021 by surrept33

[Ecocharger + 1,474]

5 hours ago, NickW said:

The observations are only charted upto 2015 which I suspect reflects when it was made. 

As for 2020 its looking like joint hottest year ever with 2016 so no evidence of any global cooling at the trough of a solar cycle. That would appear to tally with Hansens B scenario predictions out to 2020. 

No, the cooling phase rolled in during 2020, we have had a cold winter.

[turbguy + 1,544]

41 minutes ago, Ward Smith said:

Umm dude, you're just repeating my power explanation from 20 some pages ago, of course I know supply must equal demand. You've been looking at graphs at 2 AM.  I'm not convinced there's a ton of demand at that time slot, even if it is cold outside. I'd rather see the output of the SCADA system, it would make everything much clearer and the granularity is obviously much much finer.

The issue brought up in the article is that wind isn't being paid for power like every other source, but automagically gets paid for generation, no matter what. That is the fundamental flaw in the system. As with my Washington State example and wind fighting water, they also get paid for generation so happily pay the fines to BPA for ignoring the cease and desist orders from SCADA control. Since wind is the adolescent, the adults in the room need to accommodate, always. When wind is only single digit percentages of the grid it's doable but when 40% of the generated power comes from wind, Houston we have a problem! Wind cratered by 93% and after going balls to the walls for so long, that was a lot to make up. Those CCGT "peakers" aren't designed to A) go full out nor B) go full time. This episode they were called on to do both. 

@nsdp can chime in with his "insider information" but I'm a bit confused as to his pedigree. At times he's claimed to be a lawyer, a Republican committee chair, an oilman and now, apparently a power engineer. I'm curious what he'll claim next. 

This whole discussion about frequency is a red herring. Utilities don't sell "frequency" they sell "power". SCADA monitors frequency because that is the canary in the coal mine for detecting problems. Period. Full. Stop. Certainly there are devices out there that rely on frequency, such as an electric clock and synchronous motors, but even they aren't so precision that a 1/10th of a percent difference is going to break anything. No, the frequency monitoring is strictly to aid the power system because they'll catch that change faster than voltage or current issues. 

Finding out demand is easy.  It equals supply.  Finding out unserved demand, that's tougher.  You might have to ask all the consumers who lost light and heat, and add that all up.

Yup, much better granularity from SCADA is in order.  We must dig down to what actually happened during that two hour period.  Else we are just "guessing" about potential root causes.  The "WHY"?

You are arguing business and policy issues, which may indeed be valid.  Those issues can "complicate" power system business decisions (provide power, economically).  They do not explain sudden loss of scads nat gas generation (provide power, period).  That sudden drop in nat gas generation needs to be granularly explained.

CCGT plants I am familiar with are designed to go full out, for days on end (as long as they have adequate fuel and water). They tend to be cycled more often, and "deeper", which does accumulate damage that may not recognized well in the design.

Yup, frequency is the primary indicator of system balance.  That's also why you are "supposed" to operate generating plants "on speed governor". Not everybody does, nuc plants operate on Rx pressure governor, and to be honest, neither do wind plants (they can cut output, but they may, or may not, be able to increase). Since wind has no fuel or water demand, it can be really cheap.

 

Edited February 22, 2021 by turbguy

[NickW + 2,714]

11 minutes ago, Ecocharger said:

No, the cooling phase rolled in during 2020, we have had a cold winter.

No it started in 2014 which is when the solar peak occurred and bottomed out in 2019. We are actually heading towards the peak now. I appreciate the open question is about how high that peak will be. 

Have a word with your programmer - there is clearly some sort of a glitch. 

 

[NickW + 2,714]

2 minutes ago, turbguy said:

 

CCGT plants I am familiar with are designed to go full out, for days on end (as long as they have adequate fuel and water). They tend to be cycled more often, and "deeper", which does accumulate damage that may not recognized well in the design.

Yet the turbine and plant designers promote CCGT as a flexible form of electricity generation? 

[turbguy + 1,544]

3 minutes ago, NickW said:

Yet the turbine and plant designers promote CCGT as a flexible form of electricity generation? 

Yup.  They got much fast(er) ramp rates than more traditional thermal sources, until you bring up the bottoming (steam) cycle, that extra part is a little slower.

They can start up from cold much faster, too.

Edited February 22, 2021 by turbguy

[NickW + 2,714]

3 minutes ago, turbguy said:

Yup.  They got much fast(er) ramp rates than more traditional thermal sources, until you bring up the bottoming (steam) cycle, that extra part is a little slower.

They can start up from cold much faster, too.

Siemens make a particular point of this. I know another part of their business is wind turbines but they are effectively different trading divisions. 

[turbguy + 1,544]

19 minutes ago, NickW said:

Siemens make a particular point of this. I know another part of their business is wind turbines but they are effectively different trading divisions. 

Flexibility is one of the beauties of internal combustion engines (diesel included).

With a cold steam plant you gotta:

• Light a fire
• Warm up a big inventory of working fluid
• Boil (phase change) some of that inventory (I don't wanna bother with reaching supercritical here)
• Warm up all the downstream thick metallurgy
• Roll the turbine to speed and sync the generator.
• Finish heating all that thick metallurgy as you increase flow.

That can take 8 (or more) hours to reach full output.

All plants can ramp to zero really fast.  Just push one (typically red) button.

 

Edited February 22, 2021 by turbguy

[Eyes Wide Open + 3,555]

On 2/20/2021 at 9:25 PM, nsdp said:

Yes,  Wolkenkuckucksheim who has never spent a day in the oil fields.  Well heads are all above ground. 10 parts of water are produced  for every part of NG. Processing plants remove H2S, CO2, water, and propane and natural gas liquids which will freeze valves with the pressure drop and shut down production.  It is called a freeze off. Pipeline Safety Act requires 6' of cover for main lines. 3' of cover for gathering lines. 14" is an expensive safety violation.

Can a ND farm boy call his fields My Back Yard....asking for a friend of course. 

Now I do believe the frost line in TX would be 12", as to burying pipe you would be correct. I have no background hence the question what am I missing.

 

[Ward Smith + 6,615]

29 minutes ago, turbguy said:

Yup.  They got much fast(er) ramp rates than more traditional thermal sources, until you bring up the bottoming (steam) cycle, that extra part is a little slower.

They can start up from cold much faster, too.

Quote

Combined-Cycle Electricity Generation

Combined-cycle gas turbines are widely used for electricity generation from natural gas. The gas is burnt in a high-temperature gas turbine that is coupled to a generator. The exhaust gas from the turbine is used to raise steam, which is then fed to a conventional steam turbine and a further generator.

Just so we're all on the same page, this is what I mean for CCGT. Depending on how long the turbine is running will depend on how much steam is created for the secondary cycle (combined cycle). Since these are used as "peakers" they quite often never get to the steam stage of energy production. A guy calling himself "turbguy" ought to be familiar with turbines no? Essentially jet engines burning natural gas spinning a shaft turning a dynamo. On a jet airplane they're called APU'S

 

1 hour ago, NickW said:

Here the operators of Hydro can hold back

HERE they can't hold back if it's spring runoff. In jolly old England you have these molehills but here in the West we have these mountains that create a massive amount of head for the water hitting that dam in the spring. Use it or lose it (think of the 3 gorges dam in China during their flooding). That water can go over the spillway or thru the turbine but not both. In fact, for hydro, shutting down generation is non trivial as massive steel doors get closed over the entrance to the turbine inlet. 

[Ward Smith + 6,615]

25 minutes ago, turbguy said:

All plants can ramp to zero really fast.  Just push one (typically red) button.

Untrue. If you've got a gigawatt of power you don't just shunt all that to ground at the touch of a button. Well, you can, but I don't want to be anywhere around when you do.

Not relevant to this discussion but a good meme nonetheless. 

[NickW + 2,714]

29 minutes ago, turbguy said:

Flexibility is one of the beauties of internal combustion engines (diesel included).

With a cold steam plant you gotta:

• Light a fire
• Warm up a big inventory of working fluid
• Boil (phase change) some of that inventory (I don't wanna bother with reaching supercritical here)
• Warm up all the downstream thick metallurgy
• Roll the turbine to speed and sync the generator.
• Finish heating all that thick metallurgy as you increase flow.

That can take 8 (or more) hours to reach full output.

All plants can ramp to zero really fast.  Just push one (typically red) button.

 

You said it took about 45 minutes for a turbine to decelerate to zero? We were talking about nukes. 

The ramp rates on the UK coal plant (which is old built in 60's and early 70's) is about 17% per hour. I recall reading somewhere a CCGT can get up to full pelt in about 2.5 hours. 

Edited February 22, 2021 by NickW

[NickW + 2,714]

7 minutes ago, Ward Smith said:

 

HERE they can't hold back if it's spring runoff. In jolly old England you have these molehills but here in the West we have these mountains that create a massive amount of head for the water hitting that dam in the spring. Use it or lose it (think of the 3 gorges dam in China during their flooding). That water can go over the spillway or thru the turbine but not both. In fact, for hydro, shutting down generation is non trivial as massive steel doors get closed over the entrance to the turbine inlet. 

We have similar issues in western scotland at certain times of the year where they have 4-5 metres of rain per year. Furthermore they have to allow some flow irrespective of power prices to maintain the flow of rivers. 

[NickW + 2,714]

36 minutes ago, turbguy said:

Flexibility is one of the beauties of internal combustion engines (diesel included).

With a cold steam plant you gotta:

• Light a fire
• Warm up a big inventory of working fluid
• Boil (phase change) some of that inventory (I don't wanna bother with reaching supercritical here)
• Warm up all the downstream thick metallurgy
• Roll the turbine to speed and sync the generator.
• Finish heating all that thick metallurgy as you increase flow.

That can take 8 (or more) hours to reach full output.

All plants can ramp to zero really fast.  Just push one (typically red) button.

 

I recall one of the purposes of pump storage was to keep power stations 'warm' by acting as power drain during low demand and thus avoid the fatigue issues associated with cold starts on coal plant. 

[Ward Smith + 6,615]

Here is the link

Quote

Everything is so politicized these days that it is tough to decipher facts from opinions about what happened this week with the winter storm.

It’s easy to blame ERCOT — and yes, their actions led to the blackouts in part — but the full story is much more complex. One night of bad decisions would not have had such devastating consequences had it not been for decades of poor policy decisions prioritizing unreliable renewable energy sources at the expense of reliable electricity — something Texans now know is essential to our everyday lives.

I have seen a lot of media reports claiming the issue was a decrease in power generated from natural gas, but when you look at the numbers that is just not true.  According to the U.S. Energy Information Agency, the hourly average of net power generation from gas went from 17,602 mw before the storm (2/1-2/12) to 33,310 during the storm (2/12-2/17), meaning generation from natural gas basically doubled as demand increased. (1)

Many are blaming fossil fuels because "wind power was expected to make up only a fraction of what the state had planned for during the winter."(2) This is the problem. Investments in infrastructure are paid for by electricity customers and taxpayers, and our state spent more than $7 billion to build out the CREZ Transmission Lines for wind and solar generation.

This means resources that could have otherwise been spent making our grid more resilient to weather — or adding reliable generation from natural gas, nuclear, or clean coal to keep up with increasing demand for electricity — were instead spent on building out transmission lines for intermittent forms of energy that were "never expected" to perform during times like these.

The issue isn't the existence of renewable energy, but that it has displaced reliable generation that makes up our "base load," not through natural market forces but through massive subsidies and punitive regulatory policies from progressives in Washington, D.C. In 2009, “coal-fired plants generated nearly 37 percent of the state’s electricity while wind provided about 6 percent. Since then, three Texas coal-fired plants have closed… In the same period, our energy consumption rose by 20 percent.”(3)

Everyone loves to tout the phrase “all the above” — until it includes energy sources perceived as “dirty,” like coal, or "scary," like nuclear. However, these energy sources are both extraordinarily safe and dependable in adverse weather conditions like Texas is facing now because one of their key features is on-site storage. If the "all the above" wind and solar advocates are serious about anything more than receiving subsidies, why are they opposed to nuclear, which can produce massive amounts of energy with a ZERO carbon footprint?

There is no single reason we are in the mess we are in now; it is a multifaceted perfect storm. However, every time the government picks winners and losers in business and innovation, it is the average citizens that lose. This week was a wakeup call that there is more to energy policy than the politics of climate change.

1) https://mcusercontent.com/ec5dd75d998816c4f8464c9a5/files/8f37e5af-7b57-45ad-9dbb-4c7f7d0eb850/EIA_Data.xlsx
2) https://www.texastribune.org/2021/02/16/texas-wind-turbines-frozen/
3) https://comptroller.texas.gov/economy/fiscal-notes/2020/august/ercot.php

All you folks blaming gas need to explain to us why doubling  your output counts as failure? I'll wait right here…

[turbguy + 1,544]

24 minutes ago, Ward Smith said:

Just so we're all on the same page, this is what I mean for CCGT. Depending on how long the turbine is running will depend on how much steam is created for the secondary cycle (combined cycle). Since these are used as "peakers" they quite often never get to the steam stage of energy production. A guy calling himself "turbguy" ought to be familiar with turbines no? Essentially jet engines burning natural gas spinning a shaft turning a dynamo. On a jet airplane they're called APU'S

 

HERE they can't hold back if it's spring runoff. In jolly old England you have these molehills but here in the West we have these mountains that create a massive amount of head for the water hitting that dam in the spring. Use it or lose it (think of the 3 gorges dam in China during their flooding). That water can go over the spillway or thru the turbine but not both. In fact, for hydro, shutting down generation is non trivial as massive steel doors get closed over the entrance to the turbine inlet. 

I'm somewhat familiar with CCGT, have installed and commissioned a few.  Yes, you gotta raise steam and do all the steam plant stuff, but this typically takes less time than coal (say, one hour or two to reach the steamers full load).  You can raise tsteam really fast with an HRSG!  If you use it as a short term peaker, that's a much more appropriate job for a open cycle, else you just are throwing away energy to atmosphere with the CC plant. In the Texas situation, they were fast start baseload, and should have easily used the steam plant.

At to some dams, you should be able to spill and generate simultaneously. If downstream flow is too high, stop some spill or generate less.   And yes, at hydro, you cannot stop flow promptly.  The penstocks don't take to water hammer very well.

Hey, I've personally tripped 950 MW of steam while stooped over the shaft. THAT was embarrassing! 

Oh, the stories...

Edited February 22, 2021 by turbguy

[Ward Smith + 6,615]

2 minutes ago, turbguy said:

Hey, I've personally tripped 950 MW of steam while stooped over the shaft. THAT was embarrassing! 

Oh, the stories...

That's not watts, that's potential. The watts come out the other end, you just dumped the steam. Point taken however 

[turbguy + 1,544]

25 minutes ago, NickW said:

You said it took about 45 minutes for a turbine to decelerate to zero? We were talking about nukes. 

The ramp rates on the UK coal plant (which is old built in 60's and early 70's) is about 17% per hour. I recall reading somewhere a CCGT can get up to full pelt in about 2.5 hours. 

Coast down, 45 minutes, or longer or shorter.  Depends on condenser vacuum.  Nuke units are more massive, but run slower (1800 RPM v 3600 RPM) for 60 HZ systems. Either way, the last 20 RPM seems to take FOREVER!

Heavy duty gas turbine(s) can start and reach full load in say, 10 minutes (aeroderivatives, which are basically aircraft engines with a "load wheel", much faster say 30 seconds).  Bringing the bottoming steam cycle up adds the final amount of time. 

Edited February 22, 2021 by turbguy

[turbguy + 1,544]

4 minutes ago, Ward Smith said:

That's not watts, that's potential. The watts come out the other end, you just dumped the steam. Point taken however 

The generator breaker opened due to my action, simultaneously with all main and reheat steam valves snap shut (which, I also got to watch as my stomach sunk).

And the fires went out, and, and, and....

Edited February 22, 2021 by turbguy