Why does ERCOT credit wind capacity at less than 9%?
For a number of years, the planners on the ERCOT (Texas) grid assumed that wind projects would provide less than 9% of their nameplate capacity towards meeting peak demand. That assumed number for “Effective Load-Carrying Capability” (ELCC) was based on the fact that wind production is not dependable and may be inversely correlated with demand, especially during a hot summer day when there is no breeze to find.
Groups like the Sierra Club pressured ERCOT planners to use a model that did not simply assume a low number, but used selected past history to make wind appear more reliable — even if that meant an optimistic assumption that could result in capacity shortfalls under certain circumstances.
Because Texas hit a record peak demand in the past day, I went looking to see how well wind was performing and how well the new model is working out to predict its contribution to meeting the demand.
I located a page that provides data tables about ERCOT generation sources. I’m sure the tables can provide useful graphs with some moderate scripting or programming effort. Maybe someday soon, I will invest the time required, but for now I will just wish that the data sources would produce a few more graphs rather than keep burying their data in zipped CSV tables. (I know. I’m whining.)
However, I did find an illuminating graph in the file downloaded from the “Daily Aggregated Wind Output” link that illustrates the hourly variability of wind production.
(Click to enlarge.)
How would you like to operate a grid with that kind of generation variability?
That graph, with its sharp peaks and valleys, tells me that ERCOT’s 8.75% assumption for wind capacity value wasn’t too far off the mark.
The below quote from the Texas Sierra Club article titled ERCOT FINALLY VALUES WIND PEAK CAPACITY USING ACTUAL DATA, however, illustrates the risk that people who depend on reliable electricity might be taking if ERCOT allows its assumptions to be modified by pressure groups that bear no responsibility when their suggested models provide a poor basis for making decisions.
If the latest CDR, released in early 2014, used the up to date 16.3% carrying capacity of wind, (in line with the numbers presented at the recent ERCOT meeting) an additional 1,452 MW of capacity would be estimated to be added to the Texas market by 2018, therefore moving the reserve margin in 2018 from 13.4% to 15.5%. It may not sound like much out of context, but this is huge! Major investment and incentive decisions in new power plants are heavily influenced by the margin of reserves the state estimates it has. ERCOT’s current reserve margin target is 13.75%. So we essentially cross over from inadequate to adequate reserves in 2018.
Thus, by more accurately representing wind’s capacity at peak electricity use, Texans and investors in Texas will be able to see more clearly what future resources might be needed. In essence, simply by using a more accurate figure for wind capacity, Texas just gained an improvement in its reserve margin by some 2%.
Way to go wind!
You might need to read the above very carefully to see the logical flaws. If you are an experienced grid operator, you might notice the problem a little more quickly.
As usual, your comment is skewed by personal bias.
As if it’s not bad enough following load, we’ve got people by bisecting the worse than sawtooth output of wind, pretending winds output is steady. The graphs you point out are evidence.
I recommend you stand outside on any breezy day. It ebbs and waxes by the minute. Natural gas generators will become extremely important trying to fill the gaps, and they won’t be efficient combined cycle either. It’s nuts.
No amount of pretense will allow a grid to run cheaply, with low natural gas requirements on wind.
I once timed the rotation of a large modern wind turbine such as is now being placed in the hills near Tehachapi. Interesting that the rotation speed was the same even though the wind was fluctuating. I assume this is by design. (Computer regulated somehow?) Seems to me that such a system would have a consistent output even in fluctuating wind conditions. These large turbines, with huge blades driving them, seem to spin even in the lightest breeze. Sometimes I feel like many here are guilty of contempt prior to investigation. How many of you are actually abreast of the latest wind technology? Or do even care about how much you know before you lodge criticism? Chuckling, you remind me of what my own attitude about nuclear energy was when I first visited this site. Many of you are just like the so called “greens” you are so quick to criticize; close minded and overly critical. That, really, is just hypocricy.
The only contempt I feel is for groundless approbation of techniques that more firmly plant the boot heel of human presence on the natural world, for little benefit to humanity. Breezes for energy does that.
Many people confuse motion for energy. I’ll bet you don’t do that, but when you say “…seem to spin even in the slightest breeze…” you may be reinforcing a really bizarre perspective in some people, that motion equates to energy production. The blades are heavy and there will be an inertial frame kept for short periods of time. It’s also possible to graduate the power generation so that the alternator doesn’t put as much a drag on the inertial rotational frame of the blade assembly as the breeze dies down.
Wind “energy” is a fascinating thing, but I feel the concept that wind and solar is all that humanity should have, and can replace Fossil fuels (along with going without) is far too precarious a concept to press as a potential solution to the problems we face, so I won’t have it without pointing out that it’s nonsense.
“but I feel the concept that wind and solar is all that humanity should have, and can replace Fossil fuels”
I haven’t seen that “concept” advanced here by anyone. Nor have I seen it advanced by anyone outside of this blog.
I’m curious. Considering that this area does have a fairly consistent wind flow….would we be better off if these huge wind farms between Tehachapi and Mojave didn’t exist? Is it a bummer for the energy consumer that they exist? A bummer for the environment? I’m not talking about “in lieu of nuclear”. I’m talking about actual facts on the ground as we speak. Would we be better off without wind energy generation?
In my opinion, the resources that were expended to build those wind turbine farms in your area could have been better spent in a variety of other ways to build systems that would provide more reliable and environmentally friendly power, while at the same time requiring less intrusion on the natural environment.
On the other hand, having driven though the area and knowing a little about the terrain, I can see why some people think that the turbines are actually somewhat more visually attractive than the native state of the hills. When I lived in CA, I never got used to the fact that much of the state is brown or grey in the seasons when I expect lush greenery.
The Precourt Institute for Energy Research — which is hosted by a rather well-respected institute of higher learning not far from your home — tells the world that it excited about the prospects for a world supplied by 100% renewable power.
Of course, they include a few other supplementary sources in addition to wind and solar in their definition of the word “renewable,” but their definition almost certainly does not include any contribution from nuclear fission.
In fairness to the Institute, however, their web site currently includes a link to an article that is quite critical of the idea that a system based entirely on “wind, water, and sun” is a worthwhile goal if the real aim is to reduce CO2 emissions while still providing the power that our modern society needs and wants.
The Environmentalist Case Against 100% Renewable Energy Plans
It’s possible (probable?) that the link to that article was added to the site by a bot, and not by a conscious decision of someone who is a student or colleague of Stanford’s Mark Z. Jacobson.
“In my opinion, the resources that were expended to build those wind turbine farms in your area could have been better spent in a variety of other ways to build systems that would provide more reliable and environmentally friendly power, while at the same time requiring less intrusion on the natural environment”
You kinda ducked the question, Rod. You replied with a “if only we woulda”. If uou care to, read the questions again, and answer as directly as the questions were posed. Again, it was not a “in lieu of” kinda query.
“When I lived in CA, I never got used to the fact that much of the state is brown or grey in the seasons when I expect lush greenery”
Its a desert, man. The green lawns are only a product of politics and economical power. Personally, I find chaparel (sp? Getting old, sometimes I just can’t bring up the brain. Two r’s maybe??) and oak forests appealing, and the beauty of the desert can be awesome.
Where I live, a place called Stallion Springs, is high foothills and oak forest overlooking the San Joaquin Valley. The wildlife is diverse and abundant. But yeah, its real brown this time of year, and the drought is really contributing to that. And looking at the San Joaquin Valley from above and on the edge can be very depressing. The air on this end of the Valley is the worst in the nation, literally. When you look down into it you realize how badly we are blowin’ it as custodians of our environment. Thats why I am hopeful for a future that puts ALL alternatives to fossil fuel to work. And as I’ve commented here before, it is my firm belief that wind, solar geothermal, nuclear, etc will evolve scientifically through usage. Lets put all these technologies to work, and learn the lessens their usage teaches us.
Throwing stones ain’t evolution. Ideally, we need to be at a spot where we realize that our goals can be, and should be, shared.
Truthful analysis is not “throwing stones.” There is nothing wrong with certain uses of available wind and solar energy flows, but there is something wrong with trying to make them do something they are not suited to do. A kid playing basketball is a wonderful thing to watch and something that should be encouraged for a variety of reasons. Putting that kid on an NBA court and expecting him to perform is cruel, especially for someone who knows the limitations and requirements for each field of play. I cannot, in good conscience, recommend using wind or solar on the electrical power grid, which is designed to provide almost perfectly reliable, steady frequency power with a customer base that pays for the privilege of using power when it needs or wants power. The generators on the grid should be able to perform by adjusting supply as required, not by expecting customers to do the work.
When some generators have output that is outside of the control of either automated systems or human operators, all they do is add to the burden placed on all other generators.
Actually the question might be answered, if we had objective and accessable research on the comparitive advantages of wind = natural gas backup, verses natural gas in the form of CCGT generators. I have seen studies thatconcude that Wind = natural gas does not produce less CO2 than CCGTs standing alone. In this case wind is an added expense. If wind advocates want the respect of nuclear advocates, they need to be a whole lot more forth comming about the facts. Most of all they need to offer realistic plans for solving the intermittency problem, without assuming that some storage technology will save us.
“……would we be better off if these huge wind farms between Tehachapi and Mojave didn’t exist? Is it a bummer for the energy consumer that they exist? A bummer for the environment?”
Is there no one here willing to directly answer these direct questions? Is the power contributed to the grid by these wind farms a negative for the consumer? Would we, (the energy consumer), be better off if these farms didn’t exist?
@poa, who asked
“…would we be better off if these huge wind farms between Tehachapi and Mojave didn’t exist?”
If you’re asking whether we would be better off turning them off, then no. They’re here, and when the generate power, they probably displace CO2 emissions from current gas generators. I don’t have an explicit study for California, but such is the case for Ireland circa 2011, as discussed below, and it seems reasonable that might hold for California as well, though the Irish wind penetration then was 17%. I don’t know what it is for California — perhaps you can search — but it might not even be that high and in any event California is not Ireland: its bigger and its wind is more disperse. So let’s assume California does at least as well as Ireland, and each MWh of wind generation avoids at least 0.3 t CO2.
It might be more, depending on how much of the avoidance comes from Open Cycle compared with Combined Cycle combustion.
So that answers your basic question: existing California wind provides emission and economic benefit by fuel cost reduction. The “how much more” than 0.3 t I don’t know, but NREL has a recent report that is probably useful. Whether “the money could have been better spent elsewhere for greater climate benefit” is, as you observe, a different question. As is “How might money be best spent going forward if we’re to save our collective bacon from the fire?”
Ed, thank you for your response. Its the answer I’ve arrived at as well, although my answer is founded in a layman’s logic rather than science.
So, considering your response, (if it is a valid opinion), it is safe to say that “wind energy is here to stay”, eh?
Sometimes, reading the essays and comments here I get the feeling that some you are more intent on painting renewables as a bad idea than you are on painting nuclear energy as a good idea. Is that really a winning strategy? The important thing is convincing the public that the greens have an admirable goal, and as NE advocates, you share those goals, and NE can help safely and efficiently attain that goal. I realize that some of you see nefarious motive on the part of the renewable sector. But it is the way that renewables are marketed that is important. You need to get on that “we’re gonna save the planet” train, and get off that “the other guys are gonna destroy it” bandwagon. Obviously, at least here in the states, you are losing the PR battle to the greens. Keep up what you all are doing, and you’re not going to simply lose the battle, you’re going to lose the war.
Not according to Gallup:
U.S. Support for Nuclear Energy at 51%
Nearly 40% are “Concerned Believers” in global warming
For the mathematically challenged out there, I suppose that I should point out that 51% > 40%.
Jumping a train with majority support for one that is struggling to hit 40% is not what I would call a wise move.
“I cannot, in good conscience, recommend using wind or solar on the electrical power grid, which is designed to provide almost perfectly reliable, steady frequency power with a customer base that pays for the privilege of using power when it needs or wants power”
The fact is, however, that wind and solar ARE part of the grid in CA. As is fossil fuel plants and nuclear. So, Rod, are wind and solar energy’s contributions to the grid somehow hindering “this perfectly reliable, steady frequency power” that you maintain is damaged by their utility? I remember outages long before wind and solar were in usage. And even the late San Onofre, as well as Diablo, had by neccessity been temporarily removed from from the grid for upkeep, maintainance, and technical issues, eh? No system is perfect.
No system is perfect.
The same can be said of students or employees. That doesn’t, however, stop teachers and employers from noticing the fact that some students or employees are better than others. “Nothing is perfect” is a cop out.
Brian, I suggest you actually read the material you put up as rebuttal. The poll you link to butresses my assertion rather than rebuts it. Heres a direct quote from the article you linked to..
“Majority Wants More Emphasis on Solar, Wind Energy and Natural Gas”
In the same poll, 35% of Americans say the U.S. should put more emphasis on nuclear power, while 33% favor less emphasis and 28% think the emphasis should remain the same as it is now. A majority of Americans favor putting more emphasis on solar energy, wind and natural gas”
Also, the article states that since 2010 american support for NE has waned, not grown.
Try reading it, then get back to us.
I read the articles again and … guess what? They still say that the majority of Americans favor nuclear energy, and an even larger majority just don’t care that much about “saving the planet” from “Global Warming,” “Climate Change,” or whatever the mensonge du jour is these days.
That’s just the aggregate numbers from two separate polls. If we were able to investigate correlation between the fruits and nuts who want to “save the planet” and the fruits and nuts who hate nuclear power and want develop solar and wind (hint: they’re mostly the same fruits or nuts), then it would be obvious why trying to jump on the “save the planet” bandwagon is mostly a losing proposition.
I hate to say it, but these days, it seems like a book or a movie jumping on that train comes out just about every year. While I have continued to remain hopeful about these efforts, I have yet to see any significant effect on public opinion outside of a few very small special-interest groups.
Nuclear power continues to be supported by the majority of Americans, because it continues to quietly provide nearly one-fifth of the US’s electricity supply. Meanwhile, “Global Warming” continues to be an issue that limited mostly limited to a few, very shrill NGO’s, their followers, and the politicians who pander to those NGO’s.
I think it safe to say that “wind is here to stay for as long as we’re still using fossil fuels to provide base load and variable load power.”
The same may hold for hydro as well, but hydro is limited.
Hydro was a whole 6.3% of US generation last year. Nuclear generated more than 3 times as much energy.
If you changed your thinking about nuclear power, you might surprise yourself.
“I read the articles again and … guess what? They stillsay that the majority of Americans favor nuclear energy, and an even larger majority just don’t care that much about “saving the planet” from “Global Warming,” “Climate Change,” or whatever themensonge du jour is these days”
You’re simply dancing Brian. Facts are, support for nuclear is waning, and support for renewables is growing. If you don’t think thats due to marketing, then your head is in the sand. Even BP gets it, as evidenced by their switch to a green motive in their ads and logos. Even your own comment attests to this, by your comment about books.
Renewables ARE winning the PR battle, while nuclear never has enough time to elapse between between “accidents” to catch up. The public’s less than fond memory of these accidents, and exposure to so called FUD, is much stronger than the weak PR the nuclear industry engages in.
As a related aside, the nuclear energy community is shooting itself in the foot by its silence about the Iran deal that Obama has put together. You are allowing the public perception of a direct linkage between nuclear weaponry and nuclear energy, as if one goes hand and hand with other. In fact, you yourself have advocated the assasination of nuclear scientists by virtue of accusation rather than evidence. What kind of message does that send about the development of NE?
“The same can be said of students or employees. That doesn’t, however, stop teachers and employers from noticing the fact that some students or employees are better than others”
So what do we do, Rod? Fire all the less than exemplary employees, and kick the c students out of school?
Perhaps I used the wrong analogy. As your response implies, human beings have inherent value and none should be dismissed merely because they do not perform as well as others in certain settings. Some of those ‘C’ students might be working as hard as they can and are simply better suited to activities that use different skill sets than those that are favored in a classroom setting.
You’re a skilled carpenter. Presumably, you prefer to work with high quality wood that has a consistent grain pattern and with boards and sheets that have been carefully milled to close specifications.
How would you like to work for a customer who insists on trying to build good furniture by using the material from freely available twigs and branches that keep falling out of the trees in expansive pine forests? How would you feel about the effort you know is being put into trying to force those twigs and branches into useful lumber — using lots of extra glue and binders — if you knew there was a rather magical small forest nearby where the trees were not visually impressive, but where essentially unlimited quantities of amazingly consistent, high quality wood could continuously be harvested without any apparent loss of productivity and without any end in sight?
What would you think about all of the potentially skilled carpenters around the world who are unable to work because someone decided about 70 years ago that most humans should not have access to such high quality wood because it is too good and too easy to use to build high quality structures and beautiful furniture?
A “C” is a failing grade in graduate school (not that you would know that). If you are a C student, then yes, you will be kicked out of graduate school.
Ahem … “‘Beyond Petroleum’ No More? BP Goes Back to Basics”
You should try to do a better job keeping up with the times. British Petroleum is and always was an oil company — failed, cynical ad campaigns notwithstanding.
Why would anyone want to cheer a deal that gives Iran unfettered access to a nuclear weapon ten years from now (or perhaps even sooner), unless he were a madman?
“British Petroleum is and always was an oilcompany”
Are you just dense? That was my point; Even BP gets it.
So, you favor another war on Israel’s behalf. I mean, why not, Iraq has worked out so well, eh?
If we don’t lift sanctions, everyone else will. Then how effective will our sanctions be? Brian, you really need to turn off Fox news and do some actual thinking on your own. No deal is better than this deal?
You think we screwed the pooch in Iraq, just imagine the mess we can make if we go to war with Iran. And, by the way, your assertion that this deal opens a ten year window is sheer ignorance on your part. But why not? Thats what Netanyahu and his minions in our Congress are counting on.
This amazing capacity some have for listening to people whose past assertions, predictions, and policy decisions were DISASTEROUSLY WRONG just amazes me.
“A “C” is a failing grade in graduate school (not that you would know that). If you are a C student, then yes, you will be kicked out of graduate school”
Egads, you are obnoxious. How many c students make it to grad school, Brian? So whats your suggestion, Eyore? Kick ’em out while they’re in grade school?Kindergarten perhaps?
You went to grad school, Brian?
Then how come everything you seem to know came straight outta Sean Hannity’s or Glenn Beck’s mouth? Fraternity brother, or something?
But you’re kinda right. I was accepted to the Art Center College of Design just by virtue of a sketch book. So really I favor a different side of my brain than mensas like you do. Didn’t graduate though. The whole sixties thing had a firm grasp on my gonads.
“Why would anyone want to cheer a deal that gives Iran unfettered access to a nuclear weapon ten years from now (or perhaps even sooner), unless he were a madman?”
I just reread your comment, Brian. Frankly, it astounds me. I challenge you to buttress the comment with something resembling sound logic, using the actual deal, with specific details, as the basis for your assertion.
Brian…..”Why would anyone want to cheer a deal that gives Iran unfettered access to a nuclear weapon ten years from now (or perhaps even sooner), unless he were a madman?”
POA……”I just reread your comment, Brian. Frankly, it astounds me. I challenge you to buttress the comment with something resembling sound logic, using the actual deal, with specific details, as the basis for your assertion”
See, Brian. Thats the problem with simply repeating crap you hear on TV. Someone is liable to challenge you on it. Then you either gotta clam up, or make a buffoon of yourself attempting to reply.
Frankly, I think you made the right choice. At least you know when to put down the shovel.
Rod….maybe analogies ain’t exactly serving you well.
First, if I was working with twigs and branches, (which, btw, I have done), I would design keeping my material limitations in mind. Funny enough, the main chandelier in a 5000 sq ft man cave I recently worked on is made of nothing but twigs. I didn’t build it, it was actually built in Nambia. But it works well in the building. I imagine the native craftsman was happy with the medium, because he certainly made the owner of this exquisite trophy building happy.
And its rare indeed these days when I work with fine woods of a quality that was once available to me. Plys are iffy as far as thicknesses being right on. Veneers are becoming so thin on plywoods that they can barely be sanded. And old growth timber is becoming rare, with much of the better milled stock being shipped overseas. I buy the best I can when the project allows it, but long ago realized I have to do the best I can with what I can get. And I suppose I meant that as an analogy as well, if thats the manner in which we are going to debate
But you are apparently unaware of the almost magical forest that I described where there is wood whose quality is better than the old growth forest wood that is now so rare. The existence of that forest has been well obscured by those who prefer not to compete with the products that it enables.
I was fortunate enough to be introduced to that forest at the tender age of 8 and was privileged to work in it for a number of years. Unfortunately, many of my colleagues were convinced that their forest should be kept as a closely guarded secret and only used by people who have been appropriately cleared.
They goofed up by inviting some questioning thinkers into the area and giving us special knowledge with the assumption that we would follow along with the secrecy.
First, if I was working with twigs and branches, (which, btw, I have done), I would design keeping my material limitations in mind.
That is the point I am trying to make. I have worked with both the wind and the sun and designed systems that use those unreliable, but “free” energy flows. I keep their limitations in mind. Many marketers don’t. They insist on trying to force wind and solar collection systems into the “big leagues” of electrical power generation on the shared grid upon which we all depend. Those sources cannot play without substantial boosting from the public and uncompensated forced assistance from their competitors.
Using twigs to make a lighting fixture took advantage of their unique shapes for decoration – fine. How would you like to be pushed into using twig based wood products to make a display cabinet or a formal dining room table? What about using that “wood” as roof trusses under which you and your family intended to spend a few decades?
Your guess is not correct. The power produced by capturing flowing fluid, whether wind or water, is a mathematical function that depend on the fluid density and the cube of the fluid velocity.
If the wind velocity intersecting a turbine falls by a factor of 2, the power output of that turbine falls by a factor of 8.
If a turbine is designed to turn at a constant speed, the generator will be producing a variable power level that is operating at a constant frequency. That is a requirement of being a generator on an alternating current (AC) grid; all connected generators have to produce power that is at a synchronous frequency.
I’m not guilty of contempt prior to investigation; I once took several college level alternative energy production systems analysis courses. I’ve also done some informal analysis of wind power while trimming sails on a variety of sailing vessels in many different conditions.
Thanks for your reply, Rod. It is that kind of explicit response that has earned my respect for your opinions and assertions.
The adversarial crap, waged against the solar and wind advocates, gets really old. If the science is on your side, you really don’t need derision and insult, against the “greens” and renewable advocates, that I often see expressed here.
That’s only reaction. The over-selling of solar and wind and the “Green” war on nuclear energy are much older. Without those, there would be no backlash.
Had the USA simply built out nuclear power along the lines contemplated in the 1960’s (it was literally cheaper than coal under AEC rules, both to run AND to build) we would have already dealt with most of the climate issue and also much of our air-quality issue already. The fact that these problems still exist is mostly due to the anti-nuclear movement, who are useful idiots for the fossil fuel interests.
“The adversarial crap, waged against…gets really old. If the science is on your side, you really don’t need derision and insult…”
How ironic coming from you who have taken up the cudgel against quite a few in this forum. Remember your words here when next you employ this very attitude toward those who don’t subscribe to your “wisdom” on middle east affairs. If the facts are on your side, “you really don’t need derision and insult.”
Not to be too much of a stickler, and I know you were trying to keep it simple, but I don’t think most wind turbines operate at synchronous frequency. I am pretty sure they are induction generators, which operate slightly off-frequency. True synchronous generators require an exciter, which would add a lot more weight for the wind turbine nacelle.
The limitations of asynchronous generators are important to understand. They cannot be used to “black start” a dead power grid. Also, as described in the link below, they are not useful for grid frequency control. I wonder if MZ Jacobson understands that!
Frequency control is accomplished by balancing generation with demand. Intermittent sources like wind obviously make frequency control more difficult. Generators that can’t make reactive power (like induction generators) make voltage support more difficult also; a big Vermont wind farm was forced to add a “synchronous condenser” to supply its own reactive power because there were fairly frequent grid conditions when other generators couldn’t feed enough reactive power into the grid to allow the wind farm to stay on-line, and it has to be curtailed.
That’s one more thing Jacobson will never tell you.
The last page of the pdf shows how wind power output is anti-correlated with load demand. Just when the power is needed the most, in the late afternoons, wind power output is at or near the minimum. This is the typical performance in ERCOT in the summer months.
The job of the grid operator is to supply power when it is demanded by the customers. The customers do not want to be limited to using the power only when it is available.
The idea of using nuke plants to desalinate and then pump water into reservoirs seems a pretty good idea (although one has to figure out how water pumped into a common reservoir that’s filled from multiple sources, gets paid for). But what I don’t understand about your suggestion is, why use wind at all in that case? I mean, I suppose you can supplement the energy of the nuclear plant with wind power – presuming the nuke plant is producing water faster that the electricity from the nuke plant can pump it. I suppose at times of peak demand, that may actually be the case – because the grid needs the electric power, so they don’t have enough spare electricity, sans wind, to pump all the water. . . although, in that case, why not build another nuke plant or two and allow all the nuke plants on the grid to spin down 2 or 3 or 5%?
People say that nuclear plants can’t ‘load follow’ – but it seems to me that if you have a sufficiently large number of nuclear plants, you can have them load follow as a group – not by having any one plant do a large amount of adjustment in how much power it produces, but instead, have 1000 plants reduce production by 2 or 3% each and you can reduce or increase total grid generation by an amount equivalent to 20 or 30 nuclear plants going ‘offline’ – without any of them having to go offline or suffer a large output decrease?
Boiling Water Reactors can reduce power to 65% and go back up to 100% by just adjusting feed water flow.
It’s not just you, fwiw – it’s everyone, except for, presumably, Rod himself and maybe a select few other contributors.
Er, not quite. In Pete51’s ERCOT example wind varies between 1.6 GW and 10.5 GW – 656 % – while demand varies between 38 and 63 GW — only 166%. Worse, from the figure on the last page Pete51’s link, wind anti-correlates with demand. Meaning that if one has an RPS requirement that stipulates wind as “must run”, you’ve just added so much more variability with which the dispatchable generation must contend.
With increasing wind penetration, It only gets worse.
And most coal plants — all the older ones — are not happy load followers at all. I’m still collecting references, but what I’ve seen suggest these older coal plants actually emit more pollutants (including CO2) per MWh generated while load following than they do running constant baseload. That’s above the dollars cost in wear and tear of cycling that sot of plant. See my 2:00 AM post below for an example of how that plays out in real life.
btw, I think the moderation delay has to do with links, not length: the mods apparently feel obliged to check every link for appropriateness and spam. I put up with it, as its not as if I allow comments on my site. Moderation is a lot of work. But I do try to provide links supporting my own posts and encourage others to as well, whatever the delay. Unsubstantiated opinion is just that.
It isn’t just coal plants that reduce their efficiency with load-following. Combined Cycle gas plants also emit more CO2 at varying loads. See pdf link below from GE. This is a comment response to the EPA’s proposed CO2 rules. Even GE says their plants cannot meet the proposed 1000 lbs/MWh with load variations.
People who lie with statistics like using absolute numbers, without relating them to the whole.
If you actually related this to the whole, and calculated what would happen if the wind fraction was scaled up to equal the 63 GW demand peak, wind would go from 9.6 to 63 GW or a variation of almost 54 GW while demand varied by less than half that. Further, there’s no reason to expect that wind would actually produce its peak output at the time of peak demand.
But you don’t like numbers and analysis because they don’t give you the “right” answer, which is “renewables are the solution to everything”.
I quoted you directly, via copy-and-paste. Implying otherwise is a lie, but we expect that from you.
Someone needs to read up on the definition of “scare quotes”, and also on irony.
Someone needs to read up on the definition of “internet troll” … and then find a mirror.
JohnGalt stated: “We could even consider using nuke plants along the coast to produce fresh water from sea water. That is, if they really would withstand the tsunamis and earthquakes, like we were told they would before…”
This is an example of how renewables advocates use dishonest accounts of nuclear accidents to demean nuclear power. Actually the Fukushima reactors withstood both the earthquake and the tsunami, Its back up systems, fossil fuel powered generators, and grid connections to other electrical producers were not so fortunate. Recent reactor design, relying on passive safety features could have withstood the fukushema event. By the way, a near by dam failed, killing 8 people in the resulting flood. No one sees this as evidence that hydroelectric technology is flawed. I wonder why renewable advocates pay more attention to Fukushema than to the reactor failure than the dam failure. The lessons that could be learned from the 2011 Japanese dislaster have been lost, drowned out by the screams about Fukushema by renewable advocates like you.
@ Charles Barton
“I wonder why renewable advocates pay more attention to Fukushema than to …”
It doesn’t comport with their narrative. The renewable energy source, hydro, is responsible for a heck of a lot of deaths. Just one dam failure, the Banquiao Dam, resulted in at least 171,000 deaths, 6 million buildings destroyed, and 11 million left homeless; and there are many more high loss of life dam failures. Where are the hysteria mongers in the anti-nuke camp decrying such destruction and loss of life? Ah, it doesn’t comport with their narrative.
“The dam was a 60+ year old earth-fill dam…”
John, the dam was completed in 1952 and failed in 1975.
Check out the list of other dams that have failed on the link I posted. 1961 Panshet Dam in India-1000 dead; 1963 Vajont Dam in Italy-2000 dead; 1967 Sempor Dam in Indonesia-2000 dead; 1979 Machchu-2 Dam India-5000 dead; and I could go on but you can view the link.
Deaths at Fukushima, 2nd worst nuclear disaster in history–zilch.
Deaths at Chernobyl, worst nuclear disaster in history–about 60. Anti-nukes are placing their fears in all the wrong places. In addition, nuclear power saves lives by not burning coal. Per MWh of electricity produced, nuclear power has the least impact on the environment.
“It is interesting you both bring up dams as though independent from nukes, but they are not.”
You have not addressed the point I was making, ie., if concerns for safety is a driving issue for anti-nukes, then given the figures I cited, why aren’t anti-nukes concerned with dam failures but instead focus their energies on a power source that is demonstrably safer (than hydro-electric power)?
Why isn’t the fact that a dam failed at Fukushima resulting in 8 deaths compared to the zero lives lost from the nuclear plant a relevant issue? Does the Exxon Valdez accident invalidate the safety of moving oil by tanker? Does the Bhopal disaster mean mankind should not build chemical plants? Should the Challenger explosion have ended the space program?
Does the failure of two thirds of the tsunami barriers impacted by the tsunami that took out Fukushima effect your assessment of the performance of the nuclear plants?
Assuming you are a proponent of solar and wind, could you comment on the pollution from solar and wind turbine blade manufacturing as seen here?
How will the millions of solar panels be handled/discarded when they no longer serve their purpose?
We’ve spent many billions on solar and wind, considering how small the contribution these sources are to the grid, do you think we’ve gotten our money’s worth from these funds?
Have you ever seen roof top solar in a poor neighborhood? If so, how prevalent is this application in such neighborhoods? Is this a regressive tax?
Have you seen Pandora’s Promise and why do you think FORMER anti-nukes have produced a pro-nuclear documentary?
Yes, I ask a lot of questions, questions I rarely, if ever, receive answers to. You are free to ask me the same kinds of questions and I’ll give you my honest answers. I am a patriot interested in what is best for America. I’d desert nuclear power in a heart beat if something better came along. I remain at this point, wholly unconvinced that solar and wind are that something…but I am open to any and all fact based information, for or against nuclear power.
Kennedy was in the video, but says he was taken out of context in a misleading way…
The context for RFK Jr.’s appearance in Pandora’s Promise was a speech that he gave to the Colorado Oil and Gas Association. He was the lunchtime speaker. I might have a copy of the entire speech somewhere; I did watch it. In essence, RFK Jr. was promoting investments in his solar projects and political support for their subsidies by explaining the fact that they do not actually compete with oil and gas.
The man can say what he wants. He has a slanted opinion of his own actions and has some difficulty when they are captured on video for others to interpret on face value.
By the way, gas suppliers to Ivanpah, Kennedy’s biggest solar project, are happily selling more gas than the developers promised.
That result is not necessarily so pleasing to the federal and state governments who provided a substantial portion of the project funding.
Here is BrightSource’s point of view on the topic. Read it with as much critical thinking as you can muster.
Ask the same question about backup generators, or central air conditioning, cars, or you name it. Poor people have less…by definition.
Most of those products do not come with as much as 65% (North Carolina, for example provides 35% of project cost until the program runs out of money each year) of their cost paid by direct subsidies from the federal and state governments.
The EPRs under construction in Finland and France are 1650 MWe machines, not 1 GWe machines.
Vogtle and VC Summer, the two new nuclear projects in the US, are both two unit facilities, each generating 1150 MWe. Each of those projects will be completed for quite a bit less than $20 billion.
Watts Bar 2 is an outlier begun in 1973 and pursued with intermittent fits and starts almost guaranteed to increase costs to the stratosphere.
There are only a few days per year in which electric utilities need to start up their most expensive generators in order to meet peak demand. Most days, the peak is well within the capacity of baseload plus intermediate generating sources that are much more economical. In most places, including North Carolina, the actual peak loads are shifted a few hours away from the peak in solar insolation; they don’t occur in mid afternoon, but somewhat later in the evening.
… Which puts you firmly in the more cost and infrastructure for less provisioned electricity camp, poor be “darned”.
By shear coincidence there’s a brief discussion thread over at Ben Heard’s site on this very topic, wherein John Newlands introduced a curious little article by Joe Wheatley that Rod (and perhaps some others) might find of interest.
Wheatley performed an empirical analysis of power generation in Ireland, chosen because (1) the local SEMO grid operator tracks the needed data, and (2) Ireland is largely separate from the Euro grid save by a well-monitored feed from Wales.
Joe’s findings are a bit disconcerting. Wind power does not correlate with demand, and Joe provides charts of the sort Rod was looking for ERCOT. Joe then analyses the CO2 avoidance per MWh generated from wind. Irish power is generated by peat (1.19 tCO2 / MWh, similar to lignite), coal (0.89 tCO2/MWh), OCCT (56.9 tCO2/MWh), and CCGT (0.35 tCO2 / MWh when supplying baseload).
“Mean generation fractions were: (1) gas (+chp) 58% (2) wind 17% (3) coal 15% (4) peat 8%. Mean emissions fractions on the other hand were (1) gas (+chp) 49% (2) coal 31% (3) peat 19%”
These are apparently older coal and peat plants that do not load follow efficiently: cycling them to follow wind is expensive and does not save much (if any) on emissions. One surmises the OCCT are peaking plants. I haven’t found where Joe explicitly breaks out the proportion of OCCT capacity to CCGT, but his Table 2 shows total still-air CO2 emissions are 44.85% from CCGT and only 2.2% from OCCT.
The upshot of which is that when wind does show up, it primarily displaces generation from just four CCGT plants — and these are the most thermal and emissions efficient generators on the grid. But the efficiency of both drops when following wind, at which time for the 2011 Irish wind penetration (17% from Figure 1) , CCGT emissions can rise up to 0.40 tCO2/MWh and the measured effective CO2 avoidance from wind is but 0.28 t/CO2 for each MWh generated.
Meanwhile, those coal and peat plants are still chugging away at ~1.0 tCO2 per MWh generated.
There’s a quick-‘n-dirty cost/benefit analysis left in a comment. If its even close — and criticism is welcome — then if CO2 avoidance is one’s goal, and one is on a budget, then one’s pounds are better pounded on prompt decommissioning of baseload coal and peat and lignite and replacing them with baseload Combined Cycle Gas, than they are on wind. At least in Ireland wind displaces gas, but the enemy remains coal.
Someone must certainly have done a more thorough job on this, as there must be some reason for all the excitement about wind. Has anyone a link?
In 2008 I started a case study of the public health consequences of wind power in North Texas. I considered that deaths due to very high summer heat. The people dying would be primarily older people in poor health, who might be forced to live without to live without air conditioning due to grid unreliability.
Here is an example of how close Texas got clost togrid failure.
Note that AC shutdown is one of the responses, but on hot Texas summer days, widespread AC shutdown can creat a public health emergancy. It is reasonable to assume that Texas summer heat waves will become mnore frequent, longer lasting, and a greater public health problem. Texas wind capacity factors drop during the summer and drop during day time hours in West Texas, just as heat is increasing. All of these factors have to be considered if the suitability of wind to repolace fossil fuels on the grid is considered.
There’s a production graph on this page I like to use, covering a particularly productive month.
I’m not clear on how the resetting average production value at peak relates to reserve. Is this saying the higher number reflects a greater amount of reserve, or is it saying reserve backup needs to be able to cover this higher value when wind drops to zero. My understanding is that they don’t back up wind to 100% of badge capacity but only something a bit higher than average, treating it like it has a smaller overall capacity, and then just curtailing the unwanted peaks. So raising the backup levels might mean less curtailments, which might be good for wind producers, but it would also mean increasing the backup output along with associated emissions, so I don’t see any reason to cheer wind for that.
But if the higher number means wind is itself treated like a larger reserve, I don’t see how the higher average number does anything to address the troughs in production. It seems like this would just increase our reliance on wind, and our expectation that it will be available when we most need it without doing anything to improve its actual dependability–which seems like a formula for a less reliable grid overall, so I don’t see the “hooray wind” in that either.
Appears to be a lot of misinformation and misconceptions here today. Most newer Wind turbines (WT) generate a DC current which is converted to AC. Most newer WTs have variable prop blades, like on an airplane. Thus they can be prevented from over-speeding and can be adjusted to achieve maximum efficiency or needed power. There are maximum speeds and when that wind speed is reached the WT is actually shut down, and most are feathered and will not spin at all or some rotate slowly.
CCGTs are most efficient at 100% power and drop rapidly below that. All take some time to operate efficiently at full power (think of how long you wait for heat from your car heater on a very cold day) – steam is not made immediately and steam runs the other half of the combined cycle generator. Worse yet CO2 emissions also increase at lower power outputs. An older peaking unit (NON-CCTG) is more efficient and produces less CO2 at full power than a CCTG at half power. Additionally, the older peaking unit can take on the load in seconds, not tens of minutes. If you rely on a CCTG, then you may be shutting it down before you even connect it to the grid on many occasions in variable wind conditions.
Get an inexpensive weather station with a wind speed and direction gauge and mount it at least 10 feet above your roof top. That might give you an idea as to how erratic the wind is.
Visit your local Electric Company Dispatcher. Contact a troop of boy/girl Scouts, Boys & Girls Club, etc And arrange a trip the dispatchers office. Most gladly take them.
CCGTs are by far the most efficient form of natural gas generated electricity. Unfortunately wind does not play well with wind,because as Rich notes, CCGT’s are most efficient when providing 100% of capacity. They are the units that are the first to go as wind pentetration increases. The less efficient natural gas turbines produce much more CO2 at 100% power. And as I understand it, wind + NGTs produces as much CO2 as as CCGTs running at 100% output. There is no doubt that the CCGT is cheaper, and this Rich is one of the things wind advocates don’t tell us.
@ Rich and Charles
Speaking of grid, NPR ran a piece this morning on All Things Considered comparing off-grid (and undergrid) solar with simple power-grid connection in Kenya:
Second, of course — and totally unrelated — was to cobble together a water pump so they could take a shower… 🙂
Link is to the print version. Found it on The Daily Climate, which also links a National Geographic a piece today on Next-Gen Nuclear Power.
What’s going on? NPR and National Geographic aren’t exactly mainstream, but still…
Some of the emissions claims about open cycle (peaking units) versus combined cycle gas turbines are incorrect. I’ve measured these in our power station and there is a “25-35-45-55” Rule of Thumb that can be used for typical, grid-connected gas turbine efficiency:
Open Cycle GT at half load: 25% efficient; at full load 35%,
Combined Cycle at half load: 45% efficient; at full load 55%.
CO2 emissions can be directly related to cycle Efficiency as it is the same gas that is used as the fuel for open cycle as for combined cycle. So, an open cycle GT at full load is less efficient than a combined cycle plant at half load.
Also, remember that combined cycle plant consist of an open cycle GT combined with a boiler/steam plant. That GT can start up just as quickly as a traditional peaking plant if all the Grid wants is the electricity. The boiler/steam component can be introduced at a later stage to increase the electrical output and reduce the emissions without increasing the amount of gas used. This can take anything from 40 minutes to 4 hours depending on how cold the boiler/steam plant is when the process starts.
So, there is nothing that a peaking plant can do that a CCGT can’t – except achieve anything like the same efficiency!
Is the CCGT as efficient as the open cycle when you are forced
to by-pass the steam side in a rapid ramp up situation?
Yes – a CCGT with the steam side bypassed IS an open cycle GT.
So the GT exhaust temperature is the same?
If I were designing GT plants, I suspect I’d opt
for a hotter turbine exhaust temperature in the CCGT
than the Open Cycle,
But then I have absolutely no experience in gas turbines.
Do you ever have to run your turbines at zero power
just to have spinning reserve? If so, what is the rule
of thumb for fuel consumption in this mode?
Yes – the GT exhaust temperature is the same for the same GT operating in open cycle as in CCGT mode. However, different GTs have different exhaust temperatures and the higher exhaust temperature machines yield better combined cycle efficiency, as you suspected.
GT efficiency is limited then by the gas inlet temperature which is gradually increasing as new materials are developed.
A rule of thumb for full speed no load (FSNL) operation is that the thermal energy required is about the same as the electrical energy rating of the machine. So, a GT rated for 150 MW electrical output will take around 150 MW thermal to stay at FSNL. A very rough rule of thumb there…
I’ve never run a GT at FSNL for reserve reasons but it is considered as a useful service for the grid operator.
But seriously, if all it ever needs do is peak, OCCT is much cheaper (half the cost?) of CCGT. So my questions are:
(1) How often is peaking all it ever needs do?
(2) If seldom, what is the “most efficient” (you choose) power range to run a “typical” (i.e., your) CCGT? I’m assuming you’d like to keep the boiler hot and busy and ready to roar at all times, but I’m not a combustion engineer or plant operator so your real-world non-atomic insights are appreciated. Thanks!
You know your stuff so you now that if the peaker is not required often then a simple open cycle GT is going to be much cheaper overall than a CCGT.
In our smaller system, we run the CCGT frequently at minimum load (45% efficient) and then add an extra 230 MW at the peaks (55% efficient). This occurs twice daily and also if another unit fails for whatever reason or if intermittent sources drop off rapidly. We can deliver an extra 100 MW in 3 seconds when on load, which is very useful in a small system with high wind penetration.
The most efficient setup is to run all gas turbines at full load or not at all. This is not practicable for system security reasons – the extent to which the machines must be run part-loaded depends on the demand profile and the characteristics of the generation portfolio.
Denis…what software you guys use? Symphony? Ovation?
Yes, a CCGT with Condenser bypass is an OCGT. However…in my experience working as an operator at a CCGT *without* condenser bypass, is that the software just raises and lowers load by fuel control…there are minimums that can be obtained…though it they can’t, my experience with GE 7E, go much below half load. That is with CCGTs and OCGTs, regardless, there are minimum loads that cannot be exceeded which are functions not of efficiency but of turbine gas flows (usually).
A standard gas fired thermal unit (boiler/turbine/generator) has a minimum load almost 10% of it’s full load capability. This is not the case with a GT of any sort that I’m aware of.
@ David W
I agree that a CCGT with the steam turbine in service cannot normally stay on load much below 50% of its max rating. But this then leaves the other 50% available for reserve if that’s what the system wants.
However, when uncoupled (in OCGT mode), the GTs can stay synchronised at a few MWs or even reduce to zero if required (FSNL). For instance, it is not unusual to drop to 3 MWs or so when beginning to warm up a cold boiler.
There is no efficiency restriction or even turbine gas flow issues that I am aware of (and the Inlet Guide Vanes will be closed), but the emissions will be very high. Not a condition you want to experience for any longer than is absolutely necessary!!
Oh yes there is. The peaking plant can sit idle most of the year and still make a profit.
Is it whining to point out that while wind CAN produce energy, nuclear just does the job better? Can you please explain how extremely variable wind energy is superior, based upon technical characteristics, to reliable nuclear energy?
Do your homework, troll.
“Do your homework, troll”
An equally worthless response. I declare it a draw.
“If you don’t already see the obvious pros and cons, then it is a waste of time to repeat the obvious”
A worthless response.
Brave New Climate has just commenced publishing the first of a 5 part series I’ve written called “Sustaining the wind…”
It examines the question of whether, by way of comparison to nuclear, the so called “renewable energy industry” is in fact sustainable, given the inherent demand that so called “renewable energy” places on materials, in particular rare elements.
Check it out, and let me know what you think…
A pretty devastating expose on wind power. Will you be addressing the pollution from wind turbine blade manufacturing in future parts?
https://www.misoenergy.org/MarketsOperations/RealTimeMarketData/Pages/FuelMix.aspx is a great sorce of market data for the Midwest. About a month ago the wind output got down to 36MW. I have not been able to find anywhere that says what the installed capacity for the area is but I know it is grater than 11000MW.
Could you comment on the pollution from wind turbine blade manufacturing?
I don’t wish to put words in your mouth but your answer seems to suggest that because pollution is a wide spread problem in China, there is either nothing we can do about it, or its ok because the pollution is somewhere else outside America. Neither of these conclusions (I recognize you may actually have a different conclusion) comport well with the promotion of solar and wind as “Clean Technologies.” It also doesn’t address the fact that we have similar, if less severe, problems in American manufacturing of solar panels.
John, sorry I asked this question again up above but I hadn’t seen your response yet.
The reserve margin is not a very important number; it is simply a number that ERCOT calculates to have on hand. Investment decisions are based on private actors and what actually occurs. There are no monetary rewards for bidding capacity that fails to generate on peak hours.
“Major investment and incentive decisions in new power plants are heavily influenced by the margin of reserves the state estimates it has.”
This is also complete nonsense. Some time ago, ERCOT attempted to give the reserve margin force of law. The PUC released guidance saying that ERCOT would be in violation of the law if there were any attempts to proceed on this issue. About the only thing that happened was that there were big scary stories in the press about how blackouts were coming. Of course, the horror stories never came to pass.
“How would you like to operate a grid with that kind of generation variability?”
Texans are not paying for this electricity. The federal government is. The wind generators are only able to make a profit because of the wind tax credit.
The graph touches zero in places. That suggests that its “reserve capacity” value is zero.
Speaking as a resident of Texas, I’d far rather see Comanche Peak 3 & 4 built than any number of additional wind machines. That’s especially true given the State subsidies for the wind machines, & the fact that no requirement is made to set aside funds for decommissioning them. Considering the remoteness of the locations where they are typically installed, & the null scrap value of composite blades, I wonder what will happen in a few years when the oldest ones end their service lives.
Incidentally, on a recent trip, sitting on Interstate 45 midway between Houston & Dallas, I noticed that the number of wind-machine blades headed each way appeared to be equal. There is presumably some legitimate reason for this, but it seemed like a game of find-the-lady.
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