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In Oregon, Wind Power Surges Disrupting Grid
cpm99352 writes "The Oregonian reports gusts of wind cause synchronized power surges, more than the transmission lines can handle. Windmill farms are ordered to fan their blades, despite tremendous demand for 'green' power from California."
Why not use the energy during these peaks to pump water up to the top of a tower, then gradually release it as required. http://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity
The problem is not wind power, it is an electricity grid in poor condition. Frankly, that is going to be a problem with or without wind power.
SJW n. One who posts facts.
As in, "Sit in front of the turbines, flapping a big feather fan to generate more electricity?" Great idea!
My sister opened a computer store in Hawaii. She sells C shells by the seashore.
Green energy is destroying things. Let's go back to burning things just to be safe.
Why, technically speaking, is your power grid in the CA area in such poor condition? Were there missteps in its construction or maintenance? Why isn't capacity being increased? Is it a problem of deciding responsibility for organising interstate builds, and if so why don't other states suffer the problem? Spain has this on-and-off problem of autonomous regions with lots of water not providing to areas with less water; the ("federal") government of the day can determine the outcome.
McPhy claims to be able to store energy at 98% efficiency with hydrogen in solid containers,
which are precisely aimed for solving such problems.
http://www.mcphy.com/en/products/iso-containers.php
If I were investor I would look more closely to such technological advances.
So the wind turbines had to reduce production for a few hours. Is it really worth doing massive build-outs to fix that? It's sad to see energy go to waste, but on the other hand you can go outside and watch all the energy going to waste because there isn't a wind turbine to catch it in the first place!
As long we're wasting less than 10% of power (and right now we're below 1% at least in wind-farm-filled Denmark) I don't see the problem. I bet planned and unplanned maintenance accounts for several percent anyway.
Finally! A year of moderation! Ready for 2019?
I've suggested this elsewhere for other wind farms. How about having a hydrogen electrolysis plant nearby where water can be turned into Hydrogen that can be turned back into electricity during non-peak wind (tidal, or whatever) periods. Hydrogen can be burnt turning it back into water easily and produces heat that can be turned into electricity cheaply and easily. The most expensive part of the whole unit would be the hydrogen storage. This can safely be placed underground to avoid leaks and explosions if required.
There is a pretty large difference between the a power surge over a few seconds, and slowly, over the course of months, building up a supply of water in a reservoir. Dealing with a power surge over a few seconds is very hard. Dealing with a reservoir that builds up near to full is pretty freaking easy... just turn off some other power sources and slowly and predictably drain the reservoir. Unpredictability isn't the issue, rapid unpredictability is.
The problem of course is that the more you buffer something like wind energy, the less efficient (and thus more costly) it becomes. Dumping water into a reservoir will pretty much solve your energy surge problems, but it will make your output and cost crap. I bet the solution is probably more technological. Cleaning up a signal that fluctuates wildly is pretty old hat for signal folks, it just needs some scale up.
so smart, but unable to do anything to do anything about it because they're stuck there with their fingers in a dyke
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
One thing that you won't be able to predict is when the tank/lake will be so full you can't pump in it any more. I guess I'm trying to say that: what is unpredictable will stay unpredictable (no matter how many buffers you use to cushion against values you cannot handle).
How is that unpredictable? You should always know the current water level. If you know the mean and maximum pump rates as well, then you can set a computer to fan the blades on the windmills, in turn generating less electricity, when you get near the limit. If you reach the maximum very often you should think about adding a second reservoir.
It can be done. Just check how Spain manages to cope with a 41% wind energy electricity production: https://demanda.ree.es/demanda.html Check January 14th, 2010 (January = Enero).
Please google and research "peak oil" a bit. You will discover this crisis is a lot worse than they have told you
In the not-so-distant future, we may see a large number of electric vehicles on the road, with increasing policy support. The batteries in these vehicles could provide a very good distributed storage solution through an intelligent charging infrastructure.
One of the biggest arguments against wind power has been intermittency and the inability to tailor demand to supply volatility. An on-site storage can provide stability of output from the wind farm to the grid, but the options are either too ecologically-damaging (normal lead-acid batteries), or too radical (underground compressed air storage), or too debatable (hydrogen, in terms of efficiency of electrolysis, transport / storage and reconversion) and in all cases too expensive and unproven. A high capital cost of the wind farm itself ($1.5 - 1.8 mUSD / MW) and low capacity utilisation factors (27% - 35% at Class I windy sites) mean that given the current utility offtake rates in the US make the project barely viable by itself, and no developer would want to add a hugely expensive backup facility.
On the other hand, the anti-EV lobby opposes the claim of a reduced carbon footprint by a switchover to electric, by calculating the emissions related to power generation, whether through coal or gas. In this case, it would make imminent sense to use renewable sources to generate electricity for charging EV batteries. This still does not solve the issue of a limited range, which is the chief criticism of EVs.
Companies like Better Place (http://www.betterplace.com) have started lobbying hard, tying up with governments in Denmark, Israel, Australia, and local bodies in places such as San Francisco and taxis in Tokyo, to establish an EV-charging and battery swapping network to provide an innovative and seemingly practical solution to the range problem. The network they are proposing to build will keep talking to the car (such as the Nissan Leaf) to keep track of the charging status, the vehicle's position and availability of nearby swapping stations.
Further, in order to address the issue of peak demand, they also propose to charge intelligently, especially during non-peak hours. This can be done for both the battery in the car and the stock in the swapping station. Better Place also talks of buying power from renewable sources to keep the carbon footprint low.
In India, the wind power producer need not be a dedicated utility. Power can be generated by an industrial unit, fed into the grid, and a credit in terms of kWh supplied is available in the industrial unit's power bill, with banking facilities to help adjust excess generation and excess consumption. In some places, time of day metering and credit mechanism is also used to reward generation during peak hours. Similarly, a wind farm can sell power to an unrelated industrial unit too. Such a system could be introduced in the US and elsewhere.
Continued...
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"Fan the blades" is a a term of art meaning to turn the blades so that they present less resistance to the wind (and thus generate less, or even no, power)
people please stop talking about hydrogen
it wastes too much energy in electrolysis and then burning. plus its a nightmare to store and handle. there's far more efficient energy storage mediums that are far easier to manage
i wish people would just forget about hydrogen, but it seems to have entered the public conscience and will be a long time in banishing from consideration. hydrogen is not a serious green energy contender, and never will be
its too wasteful to convert to, and then convert back from, and too messy to handle. please understand these simple obvious facts that make hydrogen a complete waste of your time
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
The word is 'feather', people. You feather the blades.
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... tidal. Build a dam across the entrance of the SF bay and capture the power from the tidal flow going in and out every day. Oh, and you could build a roadway across the top of it and get rid of that ugly bridge right there.
now we need to go OSS in diesel cars
As another poster in this article noted the term is "feather" the blades, not "fan" the blades.
Mit der Dummheit kämpfen Götter selbst vergebens.
As I said, consumer demand spikes are generally predictable, so that generating capacity can be warmed up in advance. When consumers are being unpredictable, they tend to cancel out.
I have never said that renewables cannot generate enough electricity. However, in order to produce a reliable supply, renewables must be backed up by storage sufficient to cover the troughs in renewable supply by storing energy from the peaks. If you add in the entirely necessary cost for this storage, the total bill becomes much greater. We should still do it, but we must recognize the extra cost.
Wind power is particularly bad in this respect: Its peak-to-trough ratio is very high, very unpredictable, and troughs can be very long. The latest solar generators, by using thermal instead of photoelectric conversion, are able to store heat overnight in baths of molten salt and flatten out the day/night variation. These provide a much more tractable form of renewable energy.
Consciousness is an illusion caused by an excess of self consciousness.
Because you need a fragile motor/compressor for the process, and air tanks have to be re-tested yearly? Because storing air at 3,000 PSI ain't easy? It's actually a great idea; you'd eliminate the generator in the wind turbine itself, and replace it with an air compressor. Then the generator gets to live on the ground with the air motor and the generator, and hopefully the mast can be the tank. But that's still adding an air tank, compressor, and air motor where you formerly had none. Cost is the answer.
"You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
Because you need a fragile motor/compressor for the process, and air tanks have to be re-tested yearly? Because storing air at 3,000 PSI ain't easy? It's actually a great idea; you'd eliminate the generator in the wind turbine itself, and replace it with an air compressor. Then the generator gets to live on the ground with the air motor and the generator, and hopefully the mast can be the tank. But that's still adding an air tank, compressor, and air motor where you formerly had none. Cost is the answer.
The key problem here is storage you don't have to store locally. airbladders at the bottom of a lake/sea or storing the air in a disused saltmines
There are several ways that variable wind generation loads can present challenges. Texas, which has a large concentration of wind generation facilities, experienced an incident in early 2008 in which a sudden dropoff in wind triggered a grid emergency. A cold front came through, generation dipped, and utilities had to implement power shaving strategies, primarily reducing service to large customers who trade lower rates by being "interruptible."
Lots of Californians want to pay extra for green power, but do they really care who gets which power, as long as the green power is generated and used? I would guess that the vast majority of them would be fine with paying more to have green power generated and used elsewhere, but that isn't an option - when you opt into a green power program, it says you are getting that power.
The northwest already has plenty of hydropower that can be interrupted briefly while the reservoirs are allowed to fill, or at least not deplete as quickly. The wind power could be diverted to the aluminum potlines and other big users - there is still a grid issue, but much smaller than getting those big surges down to California.
A lot of this could be solved administratively, if the parties involved really wanted to solve it
It's a big problem. Grid operators are concerned about "dispatch ramp rate", the rate at which power sources can be ordered to increase or decrease output. Ramp rate from idle to full power is minutes for gas turbines, tens of minutes for hydro plants, and hours for coal plants.
Live data on this is available. Here's PJM's dashboard, with the details of the power grid in the northeastern United States. Once the dashboard (a Flash program) comes up, pick one of the graph panes, and use the drop-down menu at the upper left of the window to select "Wind Power". At the lower right of the pane, use that drop-down menu to select "All Data". The green line is total, actual wind power output for the entire PJM control area. Note that today's low is about 80MW, and today's high is about 925MW. That's how variable wind power is; over a 10:1 range in a single day. That's not just one wind farm. That's the entire northeastern US. It's not a big deal for PJM, though; their peak load today is about 130,000MW. Wind power is not yet a significant fraction of their capacity.
Wind power is not "dispatchable"; the control center can't call for more output. Current thinking is that power grids can tolerate maybe 20% to 30% wind power, maximum. There will be periods of low wind, even over very large geographical areas. Huge reserves of "dispatchable" power are needed to back up the wind turbines. Typically, that comes from natural gas fueled turbines. The backup power isn't needed very often, so the capital cost of the equipment per kilowatt hour produced is high.
Likely no one will even see this comment (there are over 300 already), but: Would it make any sense to build flywheels for energy storage on-site at wind farms, to smooth the output as well as not waste excess power generated?
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
As someone who works in the solar and wind controls business, let me state: this is not a surprise or really even a problem. People who install big wind and solar systems understand, because of the payback horizon of such installations, the limitations of the local distribution system. It is completely normal for big turbines to have to feather/furl/divert themselves during strong wind. The owners and installers design for this. It's factored into the payback time of the project!
The problem here is the sensationalist reporting. Yes, we need better electricity distribution systems for distributed generation, but we in the industry know that. We've known it for years. The guys who financed and installed the system at Columbia River Gorge almost certainly knew it.
So, yes, pump money into building bigger lines in the right places, but that's something we've been doing for more than fifty years. Generation locations are rarely at consumption locations, after all, and that was true for coal, natural gas, etc., just as it is for wind, hydro, and solar. The only problem here is that our 1990's generation locations aren't where tomorrow's generation locations are.
National Geographic Magazine did a recent article on the US power grid. Apparently it is way older and sensitive to fluctuations than I thought. It's really not set up currently to handle the erratic nature of 'green' power.
http://ngm.nationalgeographic.com/2010/07/power-grid/achenbach-text
I think another solution to using excess capacity is to produce energy intensive products. For example ammonia is like the second or third most produced chemical because the fertilizer industry buys mass quantities of it. You could think of ammonia as a nifty way of storing hydrogen because it's very easy to compress it into a liquid. For a windmill farm you would probably want to start by eletrolyzing water into O2 & H2. Then take the H2 and Air and produce your ammonia. A windmill farm might build a small mostly automated ammonia plant on site that can be switched on when the wind is blowing hard and be able to store the product for later transportation by truck.
BTM
That was the turning point of my life--I went from negative zero to positive zero.
Partly due to the title of the original post I think a lot of people are misinterpreting the issue here.
Sudden surges in wind capacity are not "disrupting the grid." nothing is broken, there are no alarms at the control station. What's happening is simply that during brief bouts of strong wind, the wind turbines are generating so much electricity that the Pacific Intertie (which carries power from Oregon to California) cannot carry it all. Power schedulers are feathering the blades of wind turbines, meaning the blades are being turned to parallel with the wind so that the turbines generate less electricity.
What does this really mean? To be honest, it's not a big deal. Frankly, I think it's cool - at times we're generating so much power with our wind capacity that it's exceeding the capabilities of the Pacific Intertie, one of the United State's largest long-distance direct-current transmission routes. From the perspective of the Bonneville Power Administration and wind capacity owners in the Pacific Northwest this is annoying, because feathering wind turbines is like opening the spillways on dams - they're effectively letting power flow by uncaptured, which means they can't sell it. If the Pacific Intertie were expanded, they could sell all of the power even during large surges, which means more money for them.
Really, though, nothing is wrong. We're saturating the intertie, which is a good thing, because that means more power for power-hungry Los Angeles, and more money for money-hungry wind turbine operators. All we need to do now is advance storage technologies (Bloom Boxes, anyone?) so that we can saturate the intertie more often.
As a note, I'm very interested in bloom boxes for storage of power from unreliable sources. The efficiency numbers Bloom Energy has published are incredibly promising.