From the American Institute of Physics
Using fluctuating wind power
Incorporating wind power into existing power grids is challenging because fluctuating wind speed and direction means turbines generate power inconsistently. Coupled with customers’ varying power demand, many wind-farm managers end up wasting power-generation capacity and limiting the service life of turbines through active control – including fully stopping turbines – in order to avoid any possible damage to the power grid from spikes in supply. In a paper published in the American Institute of Physics’ Journal of Renewable and Sustainable Energy, researchers propose a new strategy to optimize power-generation efficiency and so better control wind farms.
The new strategy is based on continuous predictions of how fluctuating winds affect each turbine’s maximum generation capacity. It also incorporates factors missing in other wind-farm control strategies, including differing power generation between turbines, actual fluctuations in power generation capacity, errors in prediction, communication disruptions preventing active control, and even turbines without the capacity for continuous active control. To demonstrate the feasibility of the new strategy, the researchers compared their predictions to raw data from a single wind turbine. The team then further refined their calculations and simulated a control operation with data from a wind farm of 33 turbines.
The results suggest that wind-farm managers can improve their power-generation efficiency with the new strategy. However, the researchers caution that before implementing the strategy, each wind-farm manager should adjust the underlying parameters – such as how often to adjust each turbine’s speed – based on local conditions.
Article: “An Active Power Control Strategy for Wind Farm Based on Predictions of Wind Turbine’s Maximum Generation Capacity,” is published in the Journal of Renewable and Sustainable Energy.
Link: http://jrse.aip.org/resource/1/jrsebh/v5/i1/p013121_s1
Authors: Dewei Liu (1), Jianbo Guo (1), Yuehui Huang (1), Weisheng Wang (1)
(1) China Electric Power Research Institute
Related articles
- Rethinking wind power – Harvard study shows it to be overestimated (wattsupwiththat.com)
- Research suggests scientists have overestimated capacity of wind farms to generate power (eurekalert.org)
- Protesters say turbines will disrupt migratory patterns of swans near Grand Bend (lfpress.com)
http://www.caiso.com/Pages/TodaysOutlook.aspx
again, looking at today, it seems that solar is almost the inverse of wind production. I’ll try to dig some longer term data.
The solution is quite simple.
1) At any given time on Earth, some wind farms are experiencing sufficient wind to power thier turbines and generate electricity.
2) Other wind farms are in the doldrums, and lack wind.
3) The solution is to erect electrically-powered fans at all wind farms such that they can be turned on when there is not sufficient natural wind.
4) Power those fans by connecting them to the output of remote wind farms that do have sufficient wind.
5) Problem solved.
Ira Glickstein
Greg said:
“I have an idea – make all wind farms virtual wind farms, model the predicted output, and pay the operators in virtual money. We can then generate all the worlds needs using virtual power, and the climate modellers can predict a virtual benefit. ”
I thought that’s what we have now.
This would seem to be a fairly minor point in the economical operation of a windmill farm from what I understand. The unexpected high cost of maintenance of wind mills is what is driving profitability (or lack thereof).
“The results suggest that wind-farm managers can improve their power-generation efficiency with the new strategy.”
“Improve” to generate a more stable power output, or “improve” to maximize the subsidies reaped?
Oh well, 1) was never an objective for them, so I guess it’s 2).
It is amazing this realization took so long. I used to be the risk manager of a large utility that also was the largest owner of wind generation in the American hemisphere (don’t know if they still are.) We realized about 12 years ago what they are saying in this article. Many don’t realize that these turbines are also stopped when there is TOO MUCH wind. But the challenge is… when do you take the brakes off? Five minutes? Fifteen? Most of these turbines came from Europe and the software which would shut them on and off was written for LOCAL EUROPEAN wind patterns. What a BIG surprise they are not suited to our local patterns.
http://content.caiso.com/green/renewrpt/DailyRenewablesWatch.pdf
Yesterdays production. Looks like wind power peak it pretty well aligned to peak demand. Solar provides a good production to fill the daytime plateau when wind is typically low.
Looks they they have some engineers designing all this, not green eared monkeys.
Isn’t this article a bit early? Like about a week early?
Bear in mind that power grids already have to deal with large changes in customer demand during the course of the day. In some cases the change from minimum to maximum daily usage can see demand double. Even without any wind power present, power grids already need (and have) the ability to scale generation up and down by bringing sources on-line and off-line. As noted in various studies including real-world examples, this means there is no need for additional “stand-by” generating reserves or power storage (nor the extra costs associated with these things) until wind power and other variable power sources account for about 10-20% of the total grid. That’s a long way off in North America.
This study is one example of those efforts. It is far too early to write off wind power as a viable source of power generation.
David Y says: Why don’t we just use wind for pumping water uphill?
Well that’s what they need to do for nuclear to make it workable since it needs to be run flat-out 24/7 to be “profitable” even if there’s little demand,(not counting back door subsidies).
Derek Sorensen says:
March 25, 2013 at 1:32 pm
“I’d be gratful for anyone more knowledgeable than me to check my assumptions/calculations because quite frankly I can’t believe the results, which seem to indicate that to guarantee 8.5Gw of power 24/7 from wind would require more than 960,000 square kilometers – almost four times the land area of the United Kingdom.”
Sounds a little too small, given that large blocking highs can turn half a continent into a region without wind for days on end. (I’m not joking. Basically any GUARANTEE with wind power only would only be achievable with a huge and ridiculously oversized system. Wind CAN’t guarantee anything, just like pigs can’t fly.)
bwdave says:
Greg said: “I have an idea – …”
Dave, if you want to make some spurious comment , do it in your own name don’t lie about what I have said.
In re Henry Clark’s superconducting grid; has anyone done a cost/benefit analysis, an analysis better than the investment schemes financing windmills and ‘needles’?
Don Quixote and his squire Sancho PONZI [sic erat scriptum] sanchismos come to mind.
Al buen callar llaman Sancho. Literal translation: The good silence is called Sancho. Meaning/use: Recommends prudence and moderation in talk.
Cada buhonero alaba sus agujas. Literal translation: A peddler praises his needles (wares). Meanings/uses: Each seller tries to convince potential buyers that his merchandise is the best. In a broader sense, people tend to praise what is theirs, often overstating qualities. Used ironically to criticize a person who boasts about his merits.
Cada gallo canta en su muladar. Literal translation: Each rooster sings on its dung-heap.
Meanings/uses: Each person rules in his own house or territory. A person manifests his true nature when surrounded by family or close friends, when in his own ambience and in his place of origin.
https://en.wikipedia.org/wiki/Spanish_proverbs
This is like Monty Python.
How about using excess wind power to store water at a high reservoir for Pumped-storage hydroelectricity when the wind doesn’t blow:
http://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity
“A new concept is to use wind turbines or solar power to drive water pumps directly, in effect an ‘Energy Storing Wind or Solar Dam’. This could provide a more efficient process and usefully smooth out the variability of energy captured from the wind or sun”
Just a thought – probably too expensive. Any thoughts on this?
Greg says:
March 25, 2013 at 1:52 pm
“David Y says: Why don’t we just use wind for pumping water uphill?
Well that’s what they need to do for nuclear to make it workable since it needs to be run flat-out 24/7 to be “profitable” even if there’s little demand,(not counting back door subsidies).”
NOBODY builds a nuke where there’s little demand, Greg. Nobody.
Dub: ” Most of these turbines came from Europe and the software which would shut them on and off was written for LOCAL EUROPEAN wind patterns. What a BIG surprise they are not suited to our local patterns.”
Presumably as “risk manager” you would quickly have realised that software is called “soft” because it can quickly and easily changed. How, as “risk manager”, did you get on with reducing the risk by having it reprogrammed to fit local wind patterns?
Greg says:
March 25, 2013 at 1:48 pm
“Yesterdays production. Looks like wind power peak it pretty well aligned to peak demand. Solar provides a good production to fill the daytime plateau when wind is typically low.
Looks they they have some engineers designing all this, not green eared monkeys.”
The primary purpose of solar cells and wind turbines is earning subsidies, not producing energy. Whether or not they produce when the other source does not produce does not affect the subsidies reaped, and is never considered in the investment decisions.
Show me one piece of evidence that your alleged “engineers” have carefully chosen to design a combination of solar and wind to achieve a stable output.
It doesn’t happen. One investor builds a windfarm. Another erects a few hectares of solar panels. Each one tries to maximize the subsidies he earns. That’s all.
Greg says:
March 25, 2013 at 1:28 pm
“The best strategy would seem to be to combine wind and solar since the two are fairly complementary in meteorological terms. ”
And abandon countries that can have blocking highs in Winter, as they would have lengthy periods without electricity. Like, Western Europe.
Mike M says:
“March 25, 2013 at 1:12 pm
How about putting a ginormous flywheel on each one or use lead blades or something? Yeah, I can fix that”!
Don’t be silly. Lead is toxic. However gold is plenty heavy, and we have tons of gold sitting in bank vaults collecting dust. As an added bonus, there would be an incentive to clean up the mess when the windmill self destructs.
Being a part time resident of Wyoming where they have serious wind, I’d like to see it used for something and that something is probably NOT going to be for electricity production. So, make Methane because we do have an infrastructure for methane transport.
There is a company that makes flywheel energy storage and I looked into it because it would be a game changer for wind power. Unfortunately, the amount of stored power/unit is small.
The best use for wind power is to power oil well pump units for stripper wells (Wells that produce less than 10 barrels/day) because it would make 1 barell/day wells profitable again. AND, I like the irony.
An even better idea, use wind power for the pumps on the Keystone pipeline………..
Derek Sorensen says:
Coincidentally, I’ve been doing some calculations recently regarding wind efficiency, and posted the results yesterday, on my blog:
http://dereksorensen.com/?p=124
I’d be gratful for anyone more knowledgeable than me to check my assumptions/calculations because quite frankly I can’t believe the results, which seem to indicate that to guarantee 8.5Gw of power 24/7 from wind would require more than 960,000 square kilometers – almost four times the land area of the United Kingdom.
===
Well the assumptions that need to be looked at are why would you need to produce a flat rate output 24/7 when demand is not 24/7 constant?
The other thing, as in my earlier comments, it that solar is generally inverse of wind. Wind/sun ratio is considerably higher for countries like UK of course. I like sun more than wind, so I left.
There are massive hydraulic storage systems in the Scottish highlands that were build to store overnight overproduction from nukes. Same principal can be used to store other energy sources that are not matched to demand.
I have not checked your calcs but I think your assumptions make that unnecessary.
Always worth doing that kind of sanity check , back of envelop, but some more reflection would seem to be in order.
Greg says:
March 25, 2013 at 1:17 pm
I have an idea – make all wind farms virtual wind farms, model the predicted output, and pay the operators in virtual money. We can then generate all the worlds needs using virtual power, and the climate modellers can predict a virtual benefit. They can all be happy and leave the rest of us alone in the real world.
__________________________________________________________________________
They do that already – it is called Sim City.
On another note I have a very whacky idea. Build a generator backup at the windfarm which can smooth the output at the windfarm itself. The backup can be the windfarm operators pedalling bicycles generators.
That should work /sarc
Petrossa says:
March 25, 2013 at 12:20 pm
So yet another extremely complex non-solution bound to fail. Just give up already
…
Yup. Too complicated by half. An interesting exercise for when we go to Mars or Titan and everything has to be fully automated and self-correcting. But economics doesn’t come into things at that point, because you are creating a survival situation, and all the “profits” are sometime in the future. If you make it until then.