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Interconnecting Wind Farms To Smooth Power Production
Posted by
Zonk
on Sat Nov 24, 2007 02:22 AM
from the sounds-like-a-plan dept.
from the sounds-like-a-plan dept.
Roland Piquepaille writes "Wind power is one of the world's fastest growing electric energy sources, but as wind is intermittent, a single wind farm cannot deliver a steady amount of energy. This is why scientists at Stanford University want to connect wind farms to develop a cheaper and more reliable power source. Interconnecting wind farms with a transmission grid should reduce the power swings caused by wind variability and provide a somewhat constant and reliable electric power (or 'baseload' power) provided by other power plants."
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Can we... (Score:5, Funny)
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WTF?? (Score:5, Informative)
Just to qualify, I have nearly a decade of experience in the energy industry, specifically electric. Right now I work for a wind power company.
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Re:WTF?? (Score:5, Funny)
We are talking about Roland here - a lot of his stuff is "just heard about something obvious - got it wrong slightly and just have to enthusiasticly share it with you."
Parent
Even then, it's the same difference. (Score:3, Interesting)
You don't need to have any experience to understand the power grid at the level of pump power in
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Yeah,
Re:WTF?? (Score:4, Interesting)
Parent
Re:WTF?? (Score:4, Informative)
Parent
Re:Homework (Score:5, Informative)
The long version is they were able to do it because there was not enough transmission capacity to import the power to replace the spike in demand from the heat wave and the shortage of online generation capacity.
Enrron was fighting price caps. It was done by selecting an upcoming period of increased demand as a time to shut down several plants for maintenance knowing the transmission infrastructure couldn't carry the load. They were hoping to use the shortage to force their hand. They pushed higher prices to ensure increased generation capacity. It fell apart when the books were examined. Somehow they didn't see that one coming.
look for the movie 'Enron
That's the Hollywood version. They take some facts and then add scriptwriters to make a drams out of it. Often the facts are ignored to make a good drama even though the movie is based on a true story. The movie doesn't have time to educate the moviegoers into the VA limitations of transmission lines, the problems with high power factor loads such as air conditioning putting additional reactive power components on the line. (How many times was MegaVars mentioned?) I'll have to watch the movie just to see if they even mention the Volt-Ampers capacity of the line. I wonder if they simply mention Mega Watts and ignore Power Factor.
The delivery capacity is real. The GP was right. The parent missed some simple homework. Here is a couple items on the capacity issue.
http://www.parapundit.com/archives/001581.html [parapundit.com]
"The Federal Energy Regulatory Commission, the agency that oversees transmission, has been trying for years to prod power companies into forming new, multi-state regional grids with authority over planning and system reliability measures. But utilities in the Southeast and Northwest fear that a more wide-open system would allow their cheaper power to be siphoned away from their customers. They have made war on FERC's plans and some members of Congress are trying to block the commission's transmission initiative from going forward until 2005 or 2007."
http://tdworld.com/mag/power_california_bulks_provide/ [tdworld.com]
"The Path 15 upgrade in California represents the first public-private partnership organized to improve a transmission system that has become seriously congested. Pointing out that Path 15 is not the only circuit that has suffered from congestion problems, the Electric Power Research Institute (EPRI; Palo Alto, California, U.S.), estimates that US$100 billion must be spent to upgrade the U.S. electricity grid."
"When the lights went out in Northern California in 2000-2001, a long-standing transmission bottleneck received national attention. A contributing factor to the crisis was a transmission constraint in Central California known as Path 15, where three 500-kV lines linking northern and southern California narrowed to two lines for 84 miles (135 km) through the Central Valley. The corridor's lack of transfer capacity hampered efforts to move available generation north from southern California and the desert southwest."
California may have enough Santa Anna winds to localy provide much wind power, but in the dog days of summer, the transmission system is not up to the task of importing sufficient power from out of state.
"By late 1998, load growth had become a significant factor for grid operators, who were prevented from moving power across the congested Path 15. The congestion hit hard in 2000 and 2001 when scarce generation forced the ISO to declare stage-three emergencies, indicating reserves were so low that rolling blackouts were imminent and resulting in several days of rotating outages of firm customer load. The emergencies extended into the winter with threats of outages continuing. Between Sept. 1, 1999, and Dec. 31, 2000, consumers spent an
Parent
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The California energy crisis was due to the breakdown of their privatization effort. New electricity generation was prohibited in the state (for a ten year or so period) while all three big electricity providers were by the end selling electricity at a low fixed rate (so no incentive for customers to reduce demand) while forced buying power at market rates. Enron and other companies engaged in a number of price fixing strategies (including taking power generation offline) which worked extremely well due to
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I'm not sure what you mean by capacity to move it around - doesn't electricity just loose strength over long distances unless the wires are made of pure gold or silver or somesuch? I don't think it's possible to move electricity from, say, New York to Los Angeles without an affordable outdoor-temperature superconductor.
Actually, (Score:2)
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Based on the summary, I tend to agree (couldn't get to the article for some reason). However, it does occur to me that if a supplier can provide easier-to-schedule wind output, which the kind of "smoothing" the article discusses might be able to provide, then perhaps there's some economic incentive for this. I agree there's no incentive from an engineering standpoint, but we all know that that isn't the
Re:WTF?? (Score:5, Informative)
In 2006, wind was 0.65%% of electrical generation
In 2005, it was 0.44%.
In 2004, it was 0.36%.
Wind is 44% of new planned electrical generation for 2007.
If current growth rates hold:
Next year, we'll generate more electricity from wind than we do from geothermal + solar + waste incinerators put together.
The year after that, we'll generate more electricity from wind than we do from all petroleum products put together.
Three more years, and wind will match hydro.
While I am extrapolating on the very high 50% growth figures... I think there is the potential for much more than that if a newly minted Democratically-controlled federal government does the environmentally sound thing and attacks coal, which is more polluting than any other energy source in pretty much every way. More CO2, more landscape destruction, more particulate matter, more sulfur, more methane, more radioactive material release, more unsafe groundwater, more mercury. A rational environmentalist with the ability to compare things (of which there are few) should table any objections that they have to other sources of energy, and protest surface coal + tarsands mining until they're banned. Yucca Mountain's worst-case-in-10,000-years-scenario is a joke compared to the devastation being doled out weekly from these two things.
Wind is already cost-competitive with coal + NG, and either wind getting increased federal subsidies of some type, wind getting significantly cheaper, or coal's externalities being priced seriously would make it much more than 44% of new capacity.
Yes, the article covers obvious points. More wind means a much more measured use of hydro, more turbine-local storage, more centralized pumped hydro storage, and more nationwide interconnects. We don't currently have a nationwide grid - we have a few small load balancing bridges between regional networks that themselves are pretty overloaded, and have trouble getting local utilities to cooperate to build more infrastructure. That would need to be built up dramatically to bring wind over 25% or so of our generation. But at the level we're at now, wind can be absorbed into slightly different duty cycles at the local hydropower quite easily.
Parent
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Coal won't be cheap forever.
Interconnected power generation systems eh? (Score:5, Funny)
Think of the possibilities!
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And now it's time for us to be reminded on a true baseline power solution, not just for this Century, but for the next one, too.
http://spacesolarpower.files.wordpress.com/2007/11/final-sbsp-interim-assessment-release-01.pdf [wordpress.com]
Brilliant... (Score:2)
Beowulf cluster (Score:3, Funny)
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Roland, wrong as usual. Here's the actual paper. (Score:5, Informative)
It's Roland the Plogger again, trying to drive traffic to his blog. It's not like he actually understands what he posts.
Here's the actual paper, Supplying Baseload Power and Reducing Transmission Requirements by Interconnecting Wind Farms [stanford.edu]. The authors have been crunching on wind speed data to try to figure out if a widespread enough set of wind farms would statistically be able to consistently produce power.
Their definition of "consistently produces power" is 79% to 92% uptime. This figure is based on the uptime for a typical single coal-fired generation unit. But they're using those numbers for a whole collection of widely distributed wind farms. That's not an appropriate comparison.
They have some moderately encouraging numbers for a set of 19 wind farms spread across a thousand kilometers, from New Mexico to Kansas. But look at Figure 3. 92% of the time, at least a quarter of average output is available. The output reliably available 99+% of the time is near zero.
What this paper actually demonstrates is that "baseload wind" isn't going to consistently provide power, even with a big grid. You need peaking plants or energy storage.
Hydro dams go well with wind... (Score:5, Informative)
The same can not be said about nuclear. I'm not sure, but I think coal and other fossil fuel power plants are not efficient at dynamic adjustments either.
Parent
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Managing supply can be done by carefully choosing when to turn on and off various sources. As the parent mentioned, nuclear, coal and fuel oil are not well-suited for rapid adjustments to power to respond to demand variation and used for base load. I was going to tell you that gas-fired pants did not fall into this categ
You are getting it backwards (Score:2)
It is your concepts of baseload and peak which are hindering your thinking. It is obvious that wind is forecastable and has slow variations in availability when many regions are connected. Thus, fuel based plants such as coal plants can be used as infrequent additions to the system
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really? so all those UK companies that stuck wind turbines in their car parks to power their factories and offices did so as a joke? or is it actually economically viable to do so? I'd guess the latter, as companies with the money to build big turbines normally don't throw money away.
The payback time (at least in the UK) on wind power is pretty long, but still sensible if you are thinking long term. And the payback time on solar AFAIK is way way better. I'd rather stick a solar he
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Small wind turbines are generally not competitive.
It's the huge, 0.5-5MW carbon-fiber-and-steel constructions placed in ideal wind zones which are competing with other forms of generation. Subsidy can allow you less efficient development, if your country has the money to burn.
The "wind turbines on car parks" are practically decorations - 90% of them are placed in areas with very little wind. Greenwashing.
Positive Energy Return On Energy Invested on wind on a good si
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That 1 plant currently produces 9% of Washington's power, btw. Around 9 billion kilowatt-hours a year. At 6 cents per kwh, t
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Failure of management doesn't speak to problems with the industry? This is our -actual experience- with the industry, not some
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http://news.bbc.co.uk/1/hi/england/london/3182961.stm [bbc.co.uk]
"The 85 metre towers with 35m blades which will make up London's first major 'wind park' have also been approved by Havering and Barking and Dagenham councils.
They will provide 100% of the electricity requirements of the new assembly hall being built to produce diesel engines at the plant. "
and that was back in 2003. with electricity prices way higher, it must make even more sense now. Some people are so excitable about wanting to buil
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Windfarms in west TX? (Score:2)
Does anyone have any more info? It stretched all the way as far as I could see from the airplane, and we flew for about 45 minutes before they stopped... it's insane.
flexible consumption (Score:3, Interesting)
ignore this article completely please (Score:2)
the biggest factor in matching wind power to the grid is not interconnecting them, the grid does that just fine, but stabilizing power output, and there are some pretty impressive solutions out there involving superconductors. Another problem is that wind power is traditionally generated best where there are by pure coincidence *no* transmission lines at all.
To offset demand you simply need overcapacity, interconnections are obvious, if the power is not brought to the grid you might as w
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The total cost of the system was quite substantial but the experience alone is priceless.
The golden rule of homep
prediction is more important (Score:2, Insightful)
a) Many industries could use power when available, not on demand. Desalination is a great example. The problem is that energy delivery and markets are not structured to work this way. Yet.
b) With short-term prediction of hours to days, you can master the variability by scheduling conventional generation around
All within moderation (Score:2)
I am not sure wether this posting will be moderated insightfull, off-topic or whatever, but at least people have an option to do it. Unfortunatly this is not possible with the obvious abusers.
oh, the humanity, er, energy (Score:2)
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Several studies
have looked at this question over the years and have concluded that wind energy has one of
the shortest energy payback times of any energy technology. A wind turbine typically takes
only a few months (3-8, depending on the average wind speed at its site) to "pay back" the
energy needed for its fabrication, installation, operation, and retirement.
Hamster power? (Score:2)
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and while we're at it can we get rid of the 'you have to wait this long before you can reply' requirement. I type fast and I'm sick and tired of having that thrown at me.
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(Just typing something random to fill in the time)
Re:don't windmills kill a large number of birds? (Score:5, Informative)
There was a concern with two series' of Appalachian ridgeline towers which were recording significant numbers of bat kills (around 1 a night per large turbine). The bats appeared on infrared to be specifically attracted to the moving propeller, particularly when it was extended to continue moving at full speed in low wind. What causes this is still under investigation, as well as potential ways to ward them off. This may have simply been because of a thriving local bat community, or merely the placement of the towers on heavily forested ridgeline, and a study done on the phenomena recommends that these be taken into account when siting towers.
Suffice it to say, though, that these are useless objections when faced with the alternative - wiping that forested Appalachian ridge clean off the face of the earth to get at the coal underneath, and dumping it into the valley on either side. This is happening now, and when you object to wind you support wind's alternatives.
Parent
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For example, compressed air requires an enormous reservoir such that the reservoir's internal temperature doesn't change significantly during the compression side of the cycle (charging the reservoir). During the expansion side of the cycle (discharging the reservoir), some source of heat is required (like burning natural gas) to counter the drop in temperature as the g