Storing Wind Power In Cold Stores

Roland Piquepaille writes "According to Nature, a European-funded project has been launched to store electricity created from wind in refrigerated warehouses used to store food. As the production of wind energy is variable every day, it cannot easily be accommodated on the electrical grid. So the 'Night Wind' project wants to store wind energy produced at night in refrigerated warehouses and to release this energy during daytime peak hours. The first tests will be done in the Netherlands this year. And as the cold stores exist already, practically no extra cost should be incurred to store as much as 50,000 megawatt-hours of energy. Here are additional details and a picture illustrating this brilliant idea."

Comments

Roland Piquepaille

[suso]

Um, what the hell? This guy has a spot on ZDnet now? At least we know what he looks like.

Re:Roland Piquepaille

[Frosty Piss]

I think really it all ties into OSTG's desire to be bought out for big $$$ by ZDNet or C|Net or even... Google? I mean come on! With so MANY of the stories here now coming from shills and whores like Roland, instead of from the MANY valid stories they get every day, well, doesn't take a rocket surgeon to figure out what the scam is here. Two words: Technocrat.net

Re:Roland Piquepaille

[yoprst]

At least we know what he looks like.
We, masters of google image search, knew this long ago

Re:Roland Piquepaille

[solevita]

When the summary said there was a picture, I didn't expect to see a blogger! I thought there'd be a windmill or something.

Re:Roland Piquepaille

[Lord_Dweomer]

How come there is no editor response? Seriously, every Roland story there are TONS of +4 and +5 comments bashing him (rightfully so), often times at the top of the comments, and yet the editors remain suspiciously silent. It is a slap in the face as a reader to be ignored like this when so much of the community is up in arms over this guy. Why do the editors refuse to give any comment on him?

Has anybody been able to do a rough calculation of how much he makes when his stories show up? Also, has anybody tried to contact ZDNet about him to complain?

But back to the core of the matter, Taco, why do you ignore us when we are all up in arms over this? It is only serving to make the editors look guilty even when that may not be the case at all. Prove us wrong!

Re:Roland Piquepaille

[StikyPad]

You say that like it's a good thing. I'm going to have orange spectacled nightmares for the rest of the week.

Re:Roland Piquepaille

[heinousjay]

I'm going to ask a (possibly stupid) question. Why the hell do people care so much about this guy? What does he do that's so offensive? Near as I can tell, it's a sort of e-penis envy caused by the fact that he can get stories posted and the rest of you can't. If that's the case, hell, I'd ignore your bitching as well.

Re:Roland Piquepaille

[Darkael]

People here hate Roland because he used to include in his submissions links to his own blog (primidi.com) which contains ads from blogads. That, and the fact that so many stories from him are accepted on Slashdot, led many slashdotters to believe that he had some sort of agreement with Slashdot editors which made both sides earn lots of money through ads.

Re:Roland Piquepaille

[Lord_Dweomer]

As someone who has had a couple stories accepted in my tenure here I'll be the first to say that has nothing to do with it. The fact is he makes money off the ad revenue and posts shitty stories containing dubious "science" stories. The other person who responded to you is correct that it used to go to his own blog. I'm not sure what his current arrangement with ZDNet is but I guarantee he gets some kind of kickback from the traffic.

April yet?

[flyingfsck]

Man, time flies. Refrigerating electricity - hmm, wonder how long it will last till it spoils?

Re:April yet?

[smartdreamer]

Maybe you are joking, but this as nothing to do with refrigerating electricity. It's about utilizing wind power to refrigirate during the night to be able to stop refrigirating during the day. Why? Because during the night, wind power over produce so it would be wasted! This is a simple idea but that can make a difference.

It reminds me about nuclear powerplants coupled with hydroelectricity. Nuclear power gives a constant output, but cannot be stopped shortly. So when they are overproducing, they pump water up transforming wasted energy in potential energy.

Re:April yet?

[Anonymous Coward]

I want to know how we can harness the power created by the vast vacuum between people that grasp sarcasm and you.

Re:April yet?

[ChrisMaple]

Sarcasm implies scorn. There is no scorn in the joke, it's just a funny look at how the subject can be misinterpreted.

Re:April yet?

[OldManAndTheC]

the power created by the vast vacuum between people that grasp sarcasm and you.

Note: the technical term for this controversial concept is zero-comphrension-of-the-point energy.

Re:April yet?

[mikael]

When I heard the term refrigerated electricity in warehouses, I imagined they were using the energy to speed up a whole warehouse of cooled down flywheels being spun up to store energy. The low temperature would be for superconducting purposes.

Re:April yet?

[caramelcarrot]

Surely this is ultimately just a half-arsed implimentation of what they really need : systems that can modify their electricity consumption based on current real-time electricity pricing. The warehouses would use more to cool down when prices are low. Prices would reduce when there's a surge of power from wind farms or any other source. That'd be more efficient "storage" - displacing demands to better times of the day. Of course designing such a system (and making it market-stable) would take more effort than changing a few time-based thermostats...

Re:April yet?

[watomb]

Ok I really don't like that this idea makes headlines as being something new. I mean would it not be better to do what New York has been doing for 30 years? Ie at night they generate more power from the falls and then pump it up to a storage lake. So during peak power they can then generate power using this stored energy, I think its something like 60% efficient. Couple that with what floridia does to keep motors(pools), and hot water heaters and you have saved more power then doing this. Was this really a new idea??? I can remeber beyond 2000 when they talked about storing thermal energy at night for some british building when electricity was cheap. In any case the only new twist was wind and I still don't think its new.
--

Re:April yet?

[cbacba]

Love it,

There seem to be many April magazine Articles that float around for years. My all time favorite is the one about 10^40 bits in a crystal or maybe it was 10^60 bits. It was enticing people into april 1 mode for years after that - spawned a number of subsequent professional articles too. All you need for a crystal is something somewhat larger than the earth - and some interface circuitry. Those who shoulda known better tended to be those who were the last to know.

This may not be quite so similar but it's definitely no new idea to store energy from production time to usage time. I guess with higher temp superconductors, maybe a nice refridgerator might be in order.

The big problem this stuff tries to address is based on the factor that peak electric loading occurs mid-day - when it's hot out, most everyone is awake and working. It is a serious problem and peak demand electricity has been a serious cost factor. Solar panels do offer peak output mid day so can help by selling some of their rather expensive electrons at primo prices. Wind often is strongest with the coastal breezes in mornings and evenings - due to unequal heating rates of water versus land.

Unfortunately, for every conversion of energy - there are thermodynamic penalties that must be paid and cannot be overcome using whatever particular technique happens to be employed in that particular circumstance. The notion of using energy in heat (or lack there of for cold) is particularly bad in cases where the resulting energy needs are in other forms - such as needing electricity again. Thermodynamic efficiencies for heat engines are a factor of the difference in temperatures between heat source and sink - and the lower the differences - the less efficient it can be.

Something as simple as cooling down commercial refridgerators at off peak hours is probably a good idea both from energy savings standpoint and from cost standpoints - assuming the insulation is sufficiently good to keep out the heat and permit a net savings. As for new innovatinve ideas it hardly seems to be something worthy of more than a passing mention in some grocery store checkout line magazine article about 10 ways to reduce your corporate electric bill.

In some areas of the country, there are systems with devices tied to electric meters that offer another, slightly more intrusive alternative which is essentially to have the equivalent of an old pre text message vintage pocket pager wired to a power relay. When the little pocket pager radio device is activated, the relay shuts off the power to the customer device for about 15 minutes. Typically, it's big ticket items for consumers like electric waterheaters, airconditioners and irrigation pumps (for farmers). This is called load shedding and it's used to minimize some of that expensive daytime peak power. One can create a rolling temporary shutdown that can shed a few million killowatts continually. Often these systems are involved with tens of thousands of customers and cover areas that could be whole states.

Like the refridgerator at night thing, it doesn't tend to save energy, but rather to distribute it around to reduce the peak load - sometimes at the expense of actually increasing the overall usage.

Re:April yet?

[Casca1]

OMG! Your post sig dates ya, man! And yes, I am waiting for my first heavenly acres factory. I know several people I want to enroll.

Re:April yet?

[smartdreamer]

Memo to myself:
- Do not reply to a post trying to be funny with an informative answer.
- Go back to this post on April's first and have a good laugh.

Holy Frozen Kippers

[The Dobber]

This has nothing to do with storing power, it's simply a transfer of usage from on-peak to off-peak.

Wow.

Re:Holy Frozen Kippers

[peterofoz]

I might have taken physics a long time ago, but we learned that you make things colder by removing energy. So there can be no such thing as cold energy storage. You can consider a cold store to be like a vacuum storage tank as it creates a difference in energy which like electricity creates potential to cause energy in the form of heat to flow. It does make sense, however, to offset energy consumption from peak hours by this method. I'd seen a design discussed in the late 70's at Orange Coast College (Calif) for chilling a cold-brine in storage tanks below office buildings, then cycling the air condiditon pipes and transferring heat from the building and warming the cold brine. They had put the whole campus on a energy management system, driven by the mainframe, and all written in APL.

Re:Holy Frozen Kippers

[Anonymous Coward]

I know Idaho Power has been doing this for at least a couple of years. They pay farmers to turn their irrigation wells off during peak periods. This is just a way to reduce demand during heavy usage.

http://www.idahopower.com/energycenter/energyeffic iency/Irrigation/irrigationPeakRewards.htm

Re:Holy Frozen Kippers

[Maddog Batty]

Why is this news? I would have thought every large cold store would be doing this already due to the difference in price of electricity. You would have thought somebody would have thought of this before. Its exactly the same principle as night storage heaters (though with cooling rather than heating) so its not exactly a major idea.

Re:Holy Frozen Kippers

[alshithead]

"This has nothing to do with storing power, it's simply a transfer of usage from on-peak to off-peak.

Wow."

You are 100% correct. It is not storing power. It IS more effectively utilizing generated power. Maybe it's not a big "wow" to you, but to me it's a fantastic (not so) common sense solution to better utilizing limited resources. The more we can utilize our resources as efficiently as possible, the less we need to generate/use/procure.

Re:Holy Frozen Kippers

[caseih]

Well electricity is not about energy storage per se so much as it is about potential difference. With mere physics alone we can show that by cooling off something to many degrees below the ambient temperature (and if we could keep it there at no cost), then we can extract energy out again (out of the ambient air) because there is a difference in temperature. Thus you can extract electricity out of the freezer from a certain point of view. Energy flows usefully in either direction. This is related to the entire field of geothermal energy production, which works in the winter so long as you have a heat sump (the earth). Of course none of this might have much to do with the original article. It's hard to know as Roland's blog adverts are often short on real details and facts. And being slashdot I can't possibly read the original article.

Re:Holy Frozen Kippers

[Anonymous Coward]

Yep. Wow. Yawn. Those Europeans are so damn smart........NOT!

Here is a much better way to store off peak energy where you can add the energy back into the grid on demand, but since it was built over 35 years ago nobody remembers or cares.

http://en.wikipedia.org/wiki/Ludington_Pumped_Stor age_Power_Plant

The Ludington Pumped Storage Plant is a hydroelectric plant and reservoir in Ludington, Michigan. It was built between 1969 and 1973.

It consists of a reservoir 110 ft (34 m) deep, 2.5 miles (4 km) long, and one mile (1.6 km) wide which holds 27 billion US gallons (100 million m) of water. The reservoir is located on the banks of Lake Michigan. The powerplant consists of six reversible turbines that can each generate 312 megawatts of electricity for a total output of 1872 megawatts. It is owned jointly by Consumers Energy and Detroit Edison and operated by Consumers Energy.

At night, during low demand for electricity, the turbines run in reverse to pump water 363 ft (110 m) uphill from Lake Michigan into the reservoir. The plant takes advantage of the natural steep sand dune landform of eastern Lake Michigan. During periods of peak demand water is released to generate power. Electrical generation can begin within 2 minutes.

This process helps level the load of coal-fired power plants on the grid. It also replaces the need to build natural gas peak power plants used only during high demand.

This project was given the 1973 award for "Outstanding Civil Engineering Achievement" by the American Society of Civil Engineers.

Re:Holy Frozen Kippers

[CnlPepper]

Yep. Wow. Yawn. Those Europeans are so damn smart........NOT! Before you go getting all jingoistic, the technology was first demonstrated by said damn smart Europeans in the 1890s. Have a read of Wikipedia's Pumped Storage Hydroelectricity page. There are plenty of examples of this technology other than the one you describe. One such example is the Dinorwig Pumped Hydro. Power station in the UK. The technology is already in widespread use.

Re:Holy Frozen Kippers

[Anonymous Coward]

With mere physics alone we can show that by cooling off something to many degrees below the ambient temperature (and if we could keep it there at no cost), then we can extract energy out again (out of the ambient air) because there is a difference in temperature. Thus you can extract electricity out of the freezer from a certain point of view. Energy flows usefully in either direction.

Yes, energy can flow in either direction. However, the efficiency varies dramatically. It is very easy to do something useful with electricity.

But, heat is the most useless form of energy. If you are going to use electricity to cool something, and later use the temperature difference of the cool object with the surroundings to create electricity, it will work, but you have created a very, very inefficient electricity storage unit.

Re:Holy Frozen Kippers

[VagaStorm]

D that and you will soon discover yor baterys aint working to well til you heet em up a bit :p

Re:Holy Frozen Kippers

[modecx]

I might have taken physics a long time ago, but we learned that you make things colder by removing energy. So there can be no such thing as cold energy storage.

If you took thermodynamics you would learn that energy can be extracted from a system with differing temperatures. By pumping the heat out of the cold storage (and the food), you use work. The heat is moved from the inside to the outside. It's like pushing a ball up a hill. Now that it's on the top of the hill you can let it go and use the potential energy you put into it for whatever purpose. It's all about the first law of thermodynamics, which is basically just the law of conservation of energy.

There are engines that directly extract work from such systems. It's all pretty basic stuff. Getting it to work, however... Not so basic. I'll be impressed if they get it to go.

Re:Holy Frozen Kippers

[SEWilco]

That's right. This has nothing to do with frozen juice.

Re:Holy Frozen Kippers

[theshowmecanuck]

The problem with wind power is that there isn't always wind. This made it sound like they found a way to store power to use when the wind isn't blowing hard enough to generate the energy required by the grid. The story turns out to show us a possible different alternative: that they should instead redirect the wind that the author is trying to blow up our asses. And why is this a 'wow'. Drawing electricity for power intensive use during off peak hours is old news.

Re:Holy Frozen Kippers

[alshithead]

"This made it sound like they found a way to store power to use when the wind isn't blowing hard enough to generate the energy required by the grid. The story turns out to show us a possible different alternative: that they should instead redirect the wind that the author is trying to blow up our asses."

I can't argue that the story is severely slanted. Still, the whole idea of taking otherwise unused energy and using it to reduce the demand on the power grid is just about sheer genius. Why the hell not conserve as much as possible in every way possible? Every watt saved helps reduce the demand on non-renewable resources.

Re:Holy Frozen Kippers

[theshowmecanuck]

I used to work in Chemical/Process Engineering before I moved into software and have seen this before. That is the point I was trying to make... people have been doing this for decades. The reason it was offered by the power company (at least on the project I worked on, oh about 18 years ago) was that they wanted to balance the power load on the grid, and so they tried to encourage major users to consume on normally off peak hours by offering cheaper rates at those times. This gave the power company a buffer so as to not have to increase capacity as much as they would otherwise would have had to (for increasing population and industry expansion). Basically the same thing as this scheme (cool extra hard at night using a lot of power when no-one else is, and use little during the day) but in this case I don't know if they are giving cash breaks. You can also see this done on really hot summer days when the grid is overwhelmed due to air conditioners. They try to get people and businesses to operate electrical equipment/appliances at staggered hours as the grid reaches capacity (e.g. Toronto the last couple of summers).

Since we are talking about wind power in this particular case, I don't know how we are conserving anything. The power is generated as long as the wind is blowing and isn't really being stored anywhere to be conserved in. If anything you are just balancing demand so that you don't have to build as many windmills. But you are still stuck if the wind doesn't blow as they aren't storing any energy with this scheme. And don't get me wrong, I agree it is a good idea... albeit an old one repackaged.

Re:Holy Frozen Kippers

[thc69]

heat is the most useless form of energy.

Tell that to this guy.

Re:Holy Frozen Kippers

[monstermagnet]

> I might have taken physics a long time ago, but we learned that you make things colder by removing energy. So there can be no such thing as cold energy storage.

Have you considered these things called "ice cubes"?

Or, more realistically for this sort of application, a thermal energy storage ("TES") material. Envision a freezer wall made with an expandable panel of blue ice... Something with a sub-zero freezing point, that can be frozen with cheap power and cools the freezer when electricity is expensive.

A quick search turned up, for example, US patent 6,370,908 (for a retail fridge).

Re:Holy Frozen Kippers

[PPH]

.... energy can be extracted from a system with differing temperatures.

This is quite true. It is possible to store energy by creating a temperature difference and later, to extract it to do work elsewhere. However, the original article doesn't describe such technology. They are simply rescheduling their energy consumption to off peak periods in order to reduce it during peak demand times.

Not a bad idea, IMHO. But having them describe it as reversible storage is bad science. Its the sort of thing that results in the creation of bad intellectual property and patents and the waste of millions of dollars in gov't R&D funding for what is essentially common sense.

Re:Holy Frozen Kippers

[An Onerous Coward]

You're fighting really hard to nail the idea over a simple semantic gaffe. When they say "store energy," they really mean "pre-use". We get that. Journalists can be idiots. We get that as well.

You're right, shifting power usage to more convenient times is a standard practice for conserving energy and smoothing out peak loads. But this is a very interesting way to do it. More important, every new method we discover for doing so makes intermittent energy sources like wind power and solar more viable.

It also highlights the need to "smarten up" our energy grid, giving the appliances connected to them information that they can use. In order for this method to work effectively (especially for smaller refrigeration units that can't hold their cold for an entire day) the unit needs to know when the grid generators are overproducing. A refrigerated warehouse could probably turn off for several hours and only rise a degree or two. But a smaller unit (maybe even a household fridge) changes temperature a lot faster, and so would need up-to-the-minute information to guide it.

Incidentally, my power company offered incentives last summer to people who would install regulators on their air conditioners, giving them some control over exactly when they turned on and off. The idea was that, by coordinating the appliances in an area, they could lower peak demand and avoid expensive infrastructure work. That idea could work well in tandem with this one.

Re:Holy Frozen Kippers

[alshithead]

"Since we are talking about wind power in this particular case, I don't know how we are conserving anything. The power is generated as long as the wind is blowing and isn't really being stored anywhere to be conserved in."

You are correct! It's not conservation in a scientific sense. It is only better utilizing and distributing the power generated. However, we need to look to these kinds of solutions in order to better increase overall utilization/optimization. Every opportunity we exploit to its fullest means less use of CO2 producing energy sources.

Re:Holy Frozen Kippers

[Bloke down the pub]

But what's new? I remember ads for this from when I was knee high to a whippersnapper.

Re:Holy Frozen Kippers

[modecx]

This is quite true. It is possible to store energy by creating a temperature difference and later, to extract it to do work elsewhere. However, the original article doesn't describe such technology. They are simply rescheduling their energy consumption to off peak periods in order to reduce it during peak demand times.

Well, I dunno if you and I read the same articles (and PDF document), but I definitely got the feeling out of both articles (and the PDF document) that they were proposing to create a thermal energy capacitor of sorts (no less than a network of them across Europe), to even out the availability of renewable energy sources, and to allow convenient output of that energy during peak hours, which often happens when such resources aren't putting out 100%.

Quoth the second article "Being a refrigeration expert, I realized the possibilities of using refrigerated warehouses as thermal energy storage and therefore as electrical energy storage," says Van der Sluis. The capacity of Europe's coldstores alone could handle more than twice the projected output of wind power in the European Union in 2010, he calculates.

Of course, there are two hurdles. These places are probably going to need lots and lots more insulation. Also, the differential probably isn't large enough to make this sort of storage very efficient. However, if they calculated that it will work, I think it's worth a go.

Re:Holy Frozen Kippers

[PPH]

Well, I dunno if you and I read the same articles (and PDF document), but I definitely got the feeling out of both articles (and the PDF document) that they were proposing to create a thermal energy capacitor of sorts (no less than a network of them across Europe), to even out the availability of renewable energy sources, and to allow convenient output of that energy during peak hours, which often happens when such resources aren't putting out 100%.

Even more abuse of technical terminology. A capacitor stores energy which can later be extracted and used elsewhere in a circuit. I don't see any description of a reversible cycle refrigeration system which would allow extraction of the 'thermal energy' stored.

Quoth the second article "Being a refrigeration expert, I realized the possibilities of using refrigerated warehouses as thermal energy storage and therefore as electrical energy storage," says Van der Sluis. The capacity of Europe's coldstores alone could handle more than twice the projected output of wind power in the European Union in 2010, he calculates.

Even worse science here. Wind energy, unlike other forms of generation, suffers from short term variations. Short term being a matter of minutes from peak to low output. Other forms of energy production (nukes, for example) have steady outputs. In this case, 'energy storage' or load shifting (which is really what it seems they are proposing) can postpone consumption during peak periods, lowering those peaks and utilize excess generation capacity during off-peak times to allow utilities to keep their generation spinning (the most economical way to run baseload plants). But that sort of peak shifting works over long periods of time. Hours between peak and off-peak utilization. Wind energy output shifts from minute to minute. It would require a real time control system to link windmill output to cold storage plants to throttle refrigeration systems up and down rapidly to produce a true 'smoothing effect' on power demand. Refrigeration plants aren't designed to run efficiently in this mode, so their owners would incur costs to cover added losses plus additional maintenance.

Re:Holy Frozen Kippers

[modecx]

Even more abuse of technical terminology. A capacitor stores energy which can later be extracted and used elsewhere in a circuit. I don't see any description of a reversible cycle refrigeration system which would allow extraction of the 'thermal energy' stored.

From the context of my wording, any half-brained nincompoop should easily understand that I wasn't referring to an electrical device, and that the function of said devices (those devices being a cold storage unit, and a capacitor) are close enough to be considered truly analogous to anyone but a rabid and confused pedant. So, which is it?

Furthermore, you need to learn to read and/or comprehend. The ZD article says this: "The idea seems simple. Say you lowered the temperature of all large coldstores in Europe by just 1C during the night when electricity demand is low, then let it rise 1C by switching them off during the day when demand is at peak. The net effect would be that the warehouses would act as batteries -- potentially storing 50,000 megawatt-hours of energy -- and the food wouldn't melt., the nature.com article says the same thing, and the PDF linked *from the site of the project* says this, "To use a refrigerated warehouse as a giant battery for wind energy. To store all electricity produced during nighttime by windmills all over Europe, and to release this energy again during the peak electricity demand hours in daytime. That is, in short, what the EU "Night Wind" project wants to demonstrate." No less than this, all of the articles outline this idea on the graphs on those articles, incidentally because they're all the same. You couldn't miss this little tidbit unless you tried!

Does that satisfy you? So, they doesn't describe the workings of the system in intricate detail, it's a freaking press report/release, it's not supposed to. They do, however, make it clear they want to test a reversible system! Regarding your last paragraph: My guess is that they will not have a single refrigeration system that's going to produce cold one minute, then turn the other way, at a moment's notice. They're probably proposing a separate engine?

what they want to do.

[PrinceAshitaka]

FTA:

The idea seems simple. Say you lowered the temperature of all large coldstores in Europe by just 1C during the night when electricity demand is low, then let it rise 1C by switching them off during the day when demand is at peak. The net effect would be that the warehouses would act as batteries -- potentially storing 50,000 megawatt-hours of energy -- and the food wouldn't melt.,

"night wind"

[macadamia_harold]

So the 'Night Wind' project wants to store wind energy produced at night in refrigerated warehouses

So do they release this "Night Wind" with a "Dutch Oven"?

Re:"night wind"

[Anonymous Coward]

This is a fart joke, and they're always funny. Mod up.

This can be used in many places

[Reverse Gear]

I think the post is a bit misleading, energy is not stored by cooling down something, actually energy is taken away, but never mind.

As far as I can figure what is being done is to cool down these refrigeration rooms more when there is more power beeing produced because of the strong wind and then you don't have to run the refrigeration systems when there is little wind for a time as they slowly heat until some level.

I would think that even more power could be saved if the energy was used to freeze water and the ice then was taken to melt in the a frame used as insulation for the freezing houses.

I don't see this as much of a new idea though, it is something that has been talked about a lot here in Denmark, there are many other places where the use of energy can be spared when there is lot's of production from windmills, for example local heating plants, smaller refrigerators in homes (would require some kind of online connection to tell them when there is cheap electricity, but I think these intelligent freezers already exist), electric cars, pretty much anything with an attached battery really.

This can to a large degree be controlled by letting the prices vary on the market and let the consumer feel these variances also, that way it pays of to use energy when there is plenty of it.

Using the power when it is produced sure is more efficient than using the extra energy to produce hydrogen, but still that is still something that I think should be still done. The two things doesn't oppose each other as such, if we are to bring down our CO2 release we sure need a lot of windmills.

Re:This can be used in many places

[Rich0]

Actually, you don't need anything quite as elaborate as what this article seems to describe. All you need is the ability for power companies to charge rates that vary in realtime based on supply/demand, and to allow customer to elect to use these rates instead of averaged-out ones.

I'm sure a lot of industrial processes work on the principle that they need to generate x quantity of some particular good in a 24 hour period, but the capacity in the plant is such that they can maybe run at less than full output for some of the day, and catch up at other times. The refrigeration in this article is just one example of this sort of thing.

If the rates varied in realtime you could design your industrial process to automatically tailor its power consumpation to the going rate. As a result you can save megabucks on your utility bill, and the utility in turn can save even more bucks on now-unneeded coal-fired plants.

The same would apply in residential situations - people could have their air conditioners fluctuate their setpoint based on the price of electricity within some limit. If during a particular hour of the day power is cheaper than average go ahead and drop the temperature an extra degree or two, and then coast through times of price-spiking. Instead of brining plants online and offline utilities would just vary the price of electricity throughout the day. If the fluctuations in price are large enough homeowners would probably buy solar-based systems or energy-storage systems of some kind (bigger water heaters that don't run during the day, storage tanks to hold cold water for cooling during the day, etc.).

Basically all you need is an electric meter with online access to the power company, and a way for power-consuming devices to find out the current rate. For cheaper devices a simple timer would at least cover general on/off-peak times.

Anything that encourages energy-users to be conscious of the realities of electrical supply/demand fluctuation will only help the environment, the supply of fuel, the general economy, etc. With the current system a kWh is a kWh and consumers have no incentive to shift their usage off-peak.

Re:This can be used in many places

[MindStalker]

Yea, a while back after Katrina or local city which runs mostly on natural gas told people to conserve and then they told people to switch their thermatates off when not at home. Consequence.. everyone gets home at 6:00 or so and turns on their airconditioning. This made matters worse as the city wasn't actually having a problem with total demand as much as peak demand...

Re:This can be used in many places

[Anonymous Coward]

Any heat gradient has the potential for use as an energy source, so in that respect 'cold' is a form of energy storage when compared with the heat surrounding it, but I agree that refrigeration is a pretty ridiculous way of storing energy - I'm sure they do mean refrigeration as a means of saving electricity, since refrigeration is expensive.

The most efficient way of storing kinetic energy is with hydroelectricity - use the wind to pump water up a hill. The energy return is by far the greatest, even given losses from evaporation and so forth during hot months with little rainfall. This is true for both small and large scale situations.

Re:This can be used in many places

[v1]

The idea here I believe is to take advantage of a large amount of energy that is available during uncertain and varying intervals. You cannot power a city on an unreliable power source without being able to store the excess for use when production is low, and the technology of storing large amounts of energy is usually limited to phyiscal storage. (energy of water in a dam for exampe)

This use of heat (or lack of heat, if you prefer to look at it that way) is just a way to buffer the supply and the demand. At night when power demand in the city is low, they divert some of the wind energy to the freezers, which drop the temperature in the cold store by a small amount. When daytime comes around, the refridgeration system has a head start on the day and less energy is taken from the grid to keep the cold storage cold. It's more efficient to turn down electricity production at a plant on a slow and large scale if you know you will need 5% less energy today than you did yesterday. If there was little wind last night then you don't get that 5% savings today, but you know that in advance. This makes an unreliable but large energy source practical to use. A savings of only a few percent makes a tremendous difference when you are talking about the power required to run an entire city. Think of how poorly engines would work without flywheels, it'd be like moving something with a jackhammer.

Re:This can be used in many places

[jbengt]

Energy IS stored by cooling something down (below ambient). It's the potential of the temperature difference that counts.

More "power" (I think you mean energy) can be stored by making ice, but if you only need more normal above-freezing temperatures, it actually takes more energy to make the ice in the first place.
You can shift peaks, but you will use more total energy in the process, since storing will always require a bigger temperature difference than immediate use, and there will be losses. If you're using "free" wind energy, you're still better off using more total energy, since it's clean and cheap compared to burning fossil fuels.

I've worked with ice storage systems and other peak time-shifting strategies before, and I can say that they are in use. But they're not common because of the first cost. Energy efficiencies like state of the art lighting, better insulation, and heat recovery should probably be considered first.

Re:This can be used in many places

[Anonymous Coward]

I'm not sure how things are in America right now, but in Australia, they're rolling out a scheme called 'Time of Use'. Meters are automatically read every 30 minutes, or every 15 for large usage sites, and you're charged based upon the time that you use the energy. Currently it's split into 3 blocks.. Peak (business times) shoulder (evenings) and off-peak (nights, weekends) and differing rates are set for each period.

Energy Australia charge 22c/kwh for Peak, 8c/kwh for Shoulder and 4c/kwh for Off-peak.

Not as elaborate as your suggestion, but far more suitable for the average home user. It would probably benefit such 'cold stores' too, because I wouldn't imagine it would make much difference whether they're -20 or -40, so they could cool right down during the night, then use less energy during 'peak' hours. I would guess future developments might see small sites charging batteries during the night to power appliances through the day.

Re:This can be used in many places

[sploxx]

Basically all you need is an electric meter with online access to the power company, and a way for power-consuming devices to find out the current rate. For cheaper devices a simple timer would at least cover general on/off-peak times.

Here in germany we have such a thing, at least for some power companies, called 'Nachtstrom' (night current). The rate for the night is about half (9ct) of the rate for the day (16ct).

Of course, the online access device would be even cooler, for private homes, I think some kind of FM radio transmission could be easily used to broadcast the rates to all homes. Signed messages would prevent unnoticed tampering. And this one-direction information flow would prevent the power companies from acquiring per-household usage patterns (which may be a privacy issue).

Re:This can be used in many places

[adrianmonk]

Actually, you don't need anything quite as elaborate as what this article seems to describe. All you need is the ability for power companies to charge rates that vary in realtime based on supply/demand, and to allow customer to elect to use these rates instead of averaged-out ones.

Very insightful comment. You should be modded up to +6 for that. It is, probably, the most general solution to this sort of problem, and if the scheme were implemented, it would motivate customers to develop load-smoothing systems on their own.

By the way, the City of Austin already has a system somewhat like this. In this part of the country, peak demand for elecricity comes on really hot days in the summer. The city-owned electric utility, Austin Energy, doesn't vary the rates, but they do have a program by which they will give you a free programmable digital thermostat which can be centrally controlled by the power company. When the thermostat is installed, they then have the right to cut the duty cycle of your A/C unit to something like 50% or 66% during peak demand; a properly-sized A/C unit will be at or near 100% duty cycle during peak times. They promise this happens only a few days each year. This clips off peaks in demand and saves them huge amounts of money they would otherwise have to invest in generation capacity. Also, if this thermostat replaces an old non-programmable one, the customer may program it to have a higher set point during peak times (which is when it saves them the most money to do so, because the duty cycle is higher when it's hotter outside), thus further reducing peak usage.

This is not exactly the same as changing the rates, but what it amounts to is that, for the price of a programmable digital thermostat (the program is voluntary), the electric company is buying the right of first refusal on sales of electricity to you. So it's still sort of market-driven.

Re:This can be used in many places

[Anonymous Coward]

Energy Australia charge 22c/kwh for Peak, 8c/kwh for Shoulder and 4c/kwh for Off-peak.

Wow. I never realized how cheap power was in Quebec, Canada. The residential rate that Hydro-Quebec charges is 5 cents/kWh for the first 30 kWh per day, and 7 cents/kWh after that (Quebec does have lots of rivers & dams).

Admittedly the Ozzie dollar and Canadian dollar aren't the same, but they are close.

Re:This can be used in many places

[Rich0]

Only problem with the thermostat solution Austin is using is that they're giving you a $20 value (digital thermostats are DIRT cheap these days), and you're not saving a dime on your electric bill (well, other than just the general benefit of higher setpoints at times - which you can get with any digital thermostat).

If they offered people 10% off their bill in exchange for the shutdown rights or something like that then you'd see it take off.

What we really need are market-based solutions. Sure, a few people will sacrifice comfort for the greater good, but if you want to really go green make it cheaper to do so. Show customers a set of super-eco-friendly appliances that also save them cash every month and people will flock to buy them. Kind of like energy-star monitors - nobody had to be told to use the features - it just made sense. I think that the concept of one-rate-24x7 needs to go away. Sure, realtime pricing would be nice, but if they at least had on/off-peak pricing you'd see a big impact in residential energy use. And you might see more solar cells on rooftops if utilities buy-back at the peak rate.

Re:This can be used in many places

[radtea]

Actually, you don't need anything quite as elaborate as what this article seems to describe. All you need is the ability for power companies to charge rates that vary in realtime based on supply/demand, and to allow customer to elect to use these rates instead of averaged-out ones.

What problem are you trying to solve?

The problem in the article is that wind power produces very large fluxuations in grid supply, and this limits the amount of wind power that can be used. In Alberta, where wind systems are localized on one area of the province, they are worried about getting much over 10% of their supply from the wind, because if it stops blowing the resulting shunting around of alternative supplies could destablize the grid.

Adding user-feedback to a moderately unstable system like the electricity grid is not necessarily the best thing to do. Adding load-leveling capacity by storing power in the form of ice is a very, very good idea.

And it is power that is being stored: temperature difference is all that matters, and it is neither more nor less correct to say that you are storing energy by cooling a block of matter below the environment than it is to say you are storing energy by heating a block of matter above the environment.

Re:This can be used in many places

[K8Fan]

A system like this is in use in Chicago, and has been for at least 10 years, called "Northwind". Commonwealth Edison, the Chicago area power company, is mostly nuclear. During summer months, the demand for electricity for cooling is much lower than during the day. So they have 2 large buildings, with huge chillers. All night long they make ice. Then during the day, the ice melts and 33 degree (F) water is distributed through pipes (using Chicago famous network of tunnels) to buildings in the downtown area. This allows builders to avoid devoting floors in new buildings for chillers and gives them more rentable space. They also avoid paying for electricity during the day to run those chillers.

Re:This can be used in many places

[FailedTheTuringTest]

Here in the UK, you can install an "economy 7" meter in your house which is essentially two meters in one, with "day" and "night" (typically 1:00-8:00 am) readings. "Night" consumption is charged at a lower rate. See for example http://en.wikipedia.org/wiki/Economy_7. All power companies support this scheme.

Re:This can be used in many places

[Ihlosi]

I think the post is a bit misleading, energy is not stored by cooling down something, actually energy is taken away, but never mind.

It's not misleading once you understand basic thermodynamics. (Usable) Energy is stored by increasing a temperature difference.

Re:This can be used in many places

[Rich0]

Adding user-feedback to a moderately unstable system like the electricity grid is not necessarily the best thing to do. Adding load-leveling capacity by storing power in the form of ice is a very, very good idea.

But in this case the load-leveling is being done by end-users. They just happen to be cooperating with the power company.

How would user-feedback make the system more unstable? Do you think that some users would set up their processes to INCREASE consumption when the price RISES? Users would either ignore the realtime rate, or they'd use it in a way that furthers the grid's goals - reducing usage when capacity is low, and raising it when capacity is high.

Right now utilities already do this in the form of on/off-peak metering. Generally only large industrial consumers are eligible (this varies greatly by country/region/etc). This is useful to save on gas-fired turbines and such, but as you point out wind is far less predictable - it might be more available at 1PM and less available at 1AM. To handle a grid with a lot of wind capacity you'd need realtime rates, and users who base their consumption on the realtime rates.

Regardless of the scheme you pick you need to make sure customers have incentive to cooperate. If you just tell them they're doing it for the common good they'll realize that they're going through a lot of trouble and possibly undertaking costs just to line utility executive pockets. If on the other hand you vary the rates in realtime, or give them breaks on their bills for participating they'll go along with it. Too often environmental initiatives are not reward-based, and as a result everybody pays them lip-service but silently undermines them. In most industries the greening-up of processes has not been the result of any desire to help out the environment, but rather large efficiency gains associated with recycling waste streams and reducing waste in general.

Re:This can be used in many places

[MaGogue]

How would user-feedback make the system more unstable? Do you think that some users would set up their processes to INCREASE consumption when the price RISES? Ah, but think about the old question of building more roads - does it help lower traffic jams or does it increase them because people simply travel more?
I believe varying rates could cause side effects such as:
-Increased consumption (additional use of energy when it is cheap without lowering consumption when it is expensive because of inappropriate buffering - air conditioning of poorly isolated homes would simply draw more energy when cheap, and not really contributing much to temperature in 6 hours)
-Innefective buffering - trying to use energy fluctuations with inappropriate devices
-Problems because of feedback loops (lowering rates triggers increase in consumption which in turn raises the rates which in turn..)

The planned approach, on the othe hand, amounts to a real and calculable decrease in energy consumption; none of the mentioned problems apply.

Re:This can be used in many places

[Bloke down the pub]

But when you understand advanced thermodynamics, you realise that making ice isn't a very efficient method for doing so.

P.S. the post is misleading, as they aren't using ice as an energy store at all, they're just moving consumption patterns around. But thanks for playing.

Re:This can be used in many places

[Rich0]

Ah, but think about the old question of building more roads - does it help lower traffic jams or does it increase them because people simply travel more?

Ugh - one of my pet-peeves... :)

The best way to eliminate traffic jams is to destroy all the roads and cars. Period.

Now, ask yourself why we have roads in the first place, and then consider whether the ability to travel more is a net benefit or problem to society.

More roads doesn't so much reduce traffic, as allow people to more easily get from point A to B when they are further apart. This means that people can specialize more in jobs (since they can work further from home), that prices are more efficient (goods move easily from point A to point B), and probably a half-dozen things I'm not thinking of.

Now, I'm all for market-based traffic solutions like congestion charges to encourage people to drive off-peak (hmm, sounds just like the article). I'm also all for innovative public transit solutions (that don't involve making a 10 mile commute take two hours via some hub 10 miles out of the way). However, solutions like "well, let's just punish people who drive by making them do so inefficiently" are really just ignoring the whole reason people drive in the first place.

Re:This can be used in many places

[GWBasic]

Actually, you don't need anything quite as elaborate as what this article seems to describe. All you need is the ability for power companies to charge rates that vary in realtime based on supply/demand, and to allow customer to elect to use these rates instead of averaged-out ones.

Be careful! Enron used such rules to artificially inflate the cost of electricity. (I believe they were turning off power plants at peak load.) It was the only business venture that they actually were profitable at.

Re:This can be used in many places

[Rich0]

Actually, the California energy crisis was the result of the exact opposite. Utilities were required to buy power at a market rate, were required to buy all power demanded (if possible), and were required to charge customers a fixed rate. Fixed rates and high demand == shortages. However, the second rule meant that even with the shortages the generation rates were huge.

The problem would have gone away if there were realtime rate charges. First, utilities would not run out of money since they could recoup their costs. Second, demand would be constrained since customers would not draw as much power when it cost $29.95/kWh (or whatever).

The problem would also have gone away if the utilities were allowed to intentionally run blackouts even when power was available in order to get a better rate. If Enron wouldn't sell power for under $14.95 per kWh, then the utilities would just flip off everybody's power until Enron gave in (the generators lose money if nobody is buying power - it works both ways). When you go shopping for a car and you find only one left on the lot, you don't tell the salesguy up-front you'll pay ANY price to get it - you just go without (unless the price is right).

The problem was a crazy regulatory environment which allowed generators to bid huge prices and as long as there was more demand than supply the high prices would be paid.

Why would he want to kill her in public?

[Dachannien]

store electricity created from wind in refrigerated warehouses

No, no, no.... There's no wind in these refrigerated warehouses. The point is that wind power fluctuates, so to smooth things out, this guy wants to use the electricity generated from wind power to overcool refrigerated warehouses at night, and then undercool them during the day when electricity demand peaks to make more of the electricity generated during the day available for other purposes.

Re:Why would he want to kill her in public?

[Anonymous Coward]

Um.. a clarification on the relevance of the subject line, please?

Re:Why would he want to kill her in public?

[Dachannien]

Mrs. White: He was deranged, he was a lunatic. He didn't actually seem to like me very much. He had threatened to kill me in public.
Miss Scarlet: Why would he want to kill you in public?
Wadsworth: I think she meant he threatened, in public, to kill her.
Miss Scarlet: Oh.

Remind me again?

[Anonymous Coward]

Remind me again why Roland Piquepaille is allowed to continue to WHORE here? A site with Slashdot's kind of volume has to stoop to Roland Piquepaille stories?

Re:Remind me again?

[MobileTatsu-NJG]

"Remind me again why Roland Piquepaille is allowed to continue to WHORE here?"

Slashdot makes money off ads. The more people (like you) there are that post/brows/etc, the more ads that are served. This story is at 100 comments now, with some thanks going to you. If you really want him to go away, try to find a way that doesn't involve Slashdot earning money off your bitching about it.

Don't they already do that?

[pijokela]

Here in Finland at least electricity is cheaper during the night, so if I had a cold store, I would already be freezing it more during the night and letting it warm during the day.

So why the hell are they not doing it already?

Re:Don't they already do that?

[wes33]

if I had a cold store, I would already be freezing it more during the night and letting it warm during the day. You're brilliant, man - but why didn't you tell anyone ???

Re:Don't they already do that?

[MichaelSmith]

So why the hell are they not doing it already?

We do it here with domestic water heaters. Its called night rate power.

Re:Don't they already do that?

[dbIII]

So why the hell are they not doing it already?

In a lot of countries they already do - so I'd say these ones would work that way too. You can't just turn a large thermal plant of any kind off for the night and switch it back on in the morning without seriously reducing its operational life, so there is always a lot of power available at night at cheap rates. The other thing is power factor - the phase of the power is skewed at night due to there being a lot of lighting and not a lot of things that use induction like motors - so power authorities/companies really like people to run certain amounts of gear at night and give them large discounts.

Although someone should send the article poster a introductory thermodynamics textbook so we could all get more of a clue what he is talking about - there is a good point there that we can solve a lot of problems by flattening out peaks. We can also use intermittant power sources for things that are not time dependant. The classic example is windmills pumping water - you don't care when it happens just so long as it moves some water over the course of the day.

Re:Don't they already do that?

[pipatron]

Here in Finland [...] freezing it more during the night and letting it warm during the day. You mean heat it more during the night and heat it less during the day? Glad I could help.

Re:Don't they already do that?

[Venerable Vegetable]

In holand we also have cheaper night energy, but this is not about day and night cycle. It's about compensating the fluctuations in wind and solar energy. Same basic idea though, but a little harder to inmplement.

Re:Don't they already do that?

[Dr. Cody]

But what do they do in the rest of the Netherlands?

Re:Don't they already do that?

[Venerable Vegetable]

Very clever, but (obviously?) I meant the whole country.

Re:Don't they already do that?

[binary_ftw]

There are some schemes to even out load on the grid by using mechanics (price fluctuations based on supply). Electricity is a very unstable commodity, so all kinds of peak-leveling, are good, since the grid is a scarce commodity, and with increasing amount of unreliable generating capacity (green stuff, like solar, wind and waves) introduced, the need to more effectively match supply and demand, initiatives like this are going to get more serious.

It's not like you can adjust your wind turbine to 10 if people start putting on those new plasma widescreens all at once. The old coal burner is a bit more simple that way.

The news-factor about this, is that a large-scale project like that, might not've been tried before, at least not with frozen storages. The only minus here, might be that they might use more electricity in total, because of increased temperature difference with the outdoors. Anyways, I loved the idea, and hope people start to be a bit more calculating with their electricity consumption as an added bonus..

We've been doing this for a very long time

[Anonymous Coward]

You can get electricity much cheaper if you're willing to let the supplier cut off your supply any time they like. For instance, we have a control wire coming into our house. It turns the water heater on and off. When electricity is in heavy demand, the water heater turns off. The wire was there when we bought the house, so the idea in the article is at least thirty years old.

Re:what they want to do.

[timeOday]

Is this really an "idea?" Energy companies have long charged different rates for power at peak and non-peak hours, which gives everybody (not just refrigeration houses) the incentive to bias their consumption towards night time if possible.

mas o menos

[TheSHAD0W]

This sounds like a very good idea. I'm wondering if the concept is already in use, though; I'm sure the warehouse owners wouldn't mind saving some on their electric bills by only utilizing electricity at off-peak times. If this is true, then the idea of storing more won't go anywhere.

This may also cause problems when you consider the food doesn't just sit there; it MOVES. Take it out to ship it to a market, and you've "lost" that cold. Move new food in and it'll absorb calories from everything around it, raising the overall temperature and requiring the refrigerators to turn back on.

Re:mas o menos

[sparr0w]

The problem is drive - most electrical companies I know don't measure based on peak and non-peak times. So here in the states, it'd take a change in how electricity is measured and billed to make this hit the main stream (and, of course, the backing of energy companies to supply such an incentive). I don't know what it's like in Europe though...

Re:mas o menos

[HankB]

It was looked at years ago. From "1997-1998 Annual Report - EPRI HVAC&R Center - Thermal Storage Applications Research Center" (University of Wisconsin, Madison" From the report (somewhere at http://www.hvacr.wisc.edu/index.htm)

Electrical Demand Reduction in
Refrigerated Warehouses
Sponsors: Alliant Energy, University-
Industry Relations, and a
Wisconsin warehouse
Status:
Complete
Graduate student Joy Altwies, with
faculty advisors Reindl and Klein,
conducted a scoping study of
demand-shifting techniques as
applied to refrigerated warehouses.
Refrigerated warehouses tradition-
ally utilize large built-up industrial
systems to cool stored products.
The refrigeration systems operate
on demand throughout the daytime.
Their highest demand usually
occurs coincidentally with the
electric utilities' peak demand. The
investigation explored the potential
of utilizing stored product as
thermal mass to shift refrigeration
loads from on-peak to off-peak
periods. The techniques developed
were tested on a pilot scale at a low-
temperature warehouse. Consider-
able energy cost savings were
achievable with minimal facility
upgrades and no degradation of
stored products.

So this is not a particularly new idea. I ran across this while looking for something about the frozen storage in Chicago. A utility facility near the Sears Tower (http://maps.google.com/maps?f=q&hl=en&q=sears+tow er&ie=UTF8&z=17&ll=41.8762,-87.635536&spn=0.003531 ,0.010182&t=k&om=1 http://tinyurl.com/2tge83)
described here: http://www.esdesign.com/projects_centralplant.htm
For those who won't follow the links:

  Exelon, District Cooling Plant #1, located in Chicago's Central Loop, is a 25,000 ton, chilled water generation plant consisting of three 5,000 ton electric motor driven centrifugal chillers and 5,500,000 pounds (66,000 ton-hour) of ice storage.

The gist of this is that they will use off peak power to make ice and then use the ice to provide cooling during peak times. Apparently a side benefit is the reduction in HVAC plants for the buildings which get their chilled water from the central plant.

20 years ago I worked in the largest steel mill in the US and they regularly scheduled production around peak demand to reduce costs, so demand management is hardly a new idea.

Potential Energy of Water

[PhotoGuy]

I've always wondered about using the potential energy of water (that is, raising it to a higher height), to store that energy to smooth out production versus demand issues for electricity.

It would likely be expensive to set up, and dependant upon the geography of an area, but the basic idea would be this: use windmills to pump water up to a basin on higher ground. Then, generate hydroelectric power at the rate desired (at night, during windless times, etc.), by letting the water fall back down to lower ground through turbines. The man-made (or even natural) lake, acts as a "battery" with the difference in height of the water that it was pumped to, being the potential energy that is stored.

Does anyone know if this is being done? It seems like it would be more straight forward than the refrigeration method mentioend in the article.

(If it's not being done, then patent-pending, patent-pending, patent-pending!)

Re:Potential Energy of Water

[Anonymous Coward]

I think that's already being done near hydroelectrics somewhere in europe no need to patent..

Re:Potential Energy of Water

[Dahan]

I've always wondered about using the potential energy of water (that is, raising it to a higher height), to store that energy to smooth out production versus demand issues for electricity.
Does anyone know if this is being done? It seems like it would be more straight forward than the refrigeration method mentioend in the article.
Have you considered Reading TFA? (Yeah, I must be new here):

... As a result many renewable-power plants have to store their energy, by raising water to a height or making hydrogen, for example, so they can 'save it for a rainy day'.

Re:Potential Energy of Water

[gtdawg]

Yes, it is being done in northern L.A. county.

http://en.wikipedia.org/wiki/Castaic_Dam

http://www.osti.gov/energycitations/product.biblio .jsp?osti_id=7092283

Re:Potential Energy of Water

[Anonymous Coward]

http://en.wikipedia.org/wiki/Ben_Cruachan

Re:Potential Energy of Water

[Anonymous Coward]

Yes, it's done in various places. For example, look at http://www.fhc.co.uk/ffestiniog.htm

Re:Potential Energy of Water

[noigmn]

If I read it correctly this is one of the most standard, old and efficient means of energy storage. If you tried to patent it you would probably make a bit of a fool of yourself :). You'd probably have about as much chance of patenting the wheel, though with the way they give out patents these days there's always a chance.

On the subject of cold energy storage I thought they might be putting the batteries in the fridges to cool them and make them more efficient. But like most good things the simple ideas are usually the best. It's just use of power when it is most efficient to use it. ie. use the wind power off peak when the winds are so there isn't a need to store it. And lower the peak power. Obviously you could just use the coal power from the grid off peak when it's in low demand to do the same thing, but it doesn't sound as green.

Re:Potential Energy of Water

[mccdyl001]

This has been implemented near Cape Town in South Africa. During the evenings, hen demand for electricity is low, they pump water from a resevoir on the cape flats (i.e. nearly at sea level)(google maps link) up to the top of a nearby mountain (link to it on google maps. Then during the day, when the electricity is needed, they let the water flow back down and power a turbine generating surplus for the grid. I think this was implemented since pretty much all of cape town's electricity is supplied by Koeberg nuclear power station (when the turbines aren't breaking down), and from what i can gather, the electrical output from a nuclear plant is pretty constant and would otherwise be wasted if there was not some way to temporarily store it during quiet times for use in peak times.

Actually, I was once speaking to a farmer who owns the farm that the upper resevoir is located next to, and he pointed out a large many-story high concrete pillar (you can see it in the google maps link to the upper resevoir i inserted earlier in this post, to the lower right hand corner of the dam). He reckons, and i have no reason to doubt him, that its there to absorb the backward wave of water that is created when the downward flow is shut off each night. The way he explained it was its almost like a super large tidal bore flows back up the pipeline that was drilled through the mountain to the lower reservoir. Supposedly it would spout a column of water about 50 meters into the air otherwise. Anyway,thats totally irrelevant to the article, just thought it would make the links a bit more interesting.

Re:Potential Energy of Water

[NoMaster]

... and he pointed out a large many-story high concrete pillar ... there to absorb the backward wave of water ...

Yup, very probably. I don't know about that particular installation, but the Snowy Mountains scheme here in Australia has something very similar - big caverns bored out and connected to the through-mountain tunnels are used to damp the shock wave caused when the gates are closed. Basically a giant version of the anti-hammer devices you can get for your household plumbing.

Buggered if I can find a diagram of it on-line though...

Re:Potential Energy of Water

[Frodo2002]

Yes, this idea has already been considered and implemented, but it does not work very well. In South Africa, the Tugela-Vaal water transfer scheme has been in operation from 1974 or thereabouts. If you want to read about it, check out this article. Scroll a little more than halfway down the page to the heading that says "Transfer Schemes". The Tugela-Vaal scheme is illustrative because its primary function is to transfer water from the Tugela River, over the Drakensberg mountains to the Vaal River. The fact that they can run the pumps in reverse as turbines for peak power periods, is really only an added bonus, it is NOT the primary reason for the existence of the whole thing. So why doesn't your idea really work? Well there are just too many losses. Energy is lost to: evaporation from the dam surface, compression of the water, heating of the water, friction (viscocity), the inefficiencies of the turbines/pumps etc etc. Each loss is fairly small by itself. But when you add them all up, it turns out that storing energy by raising water basically sucks. Sorry :(

Re:Potential Energy of Water

[Anonymous Coward]

(If it's not being done, then patent-pending, patent-pending, patent-pending!)

Sorry, It's already being done in lots of places

Grand Coulee Dam has had these for decades, and I doubt it's the first.

Re:Potential Energy of Water

[Anonymous Coward]

Wouldn't it be easier to just close the gates slowly?

IANAHE (clearly)

Re:Potential Energy of Water

[stereoroid]

I've always wondered about using the potential energy of water (that is, raising it to a higher height), to store that energy to smooth out production versus demand issues for electricity.

Yes - it's being done in South Africa, the Drakensberg Pumped Storage Scheme.

Re:Potential Energy of Water

[Anonymous Coward]

They already do this in New Jerey. Lots of nuclear power here, can't really just turn it off at night.

Up by the Delaware Water Gap, they pump water to holding ponds at the top of a hill. When they need some extra electricity they release the water back down a pipe and spin some turbines at the bottom of the hill.

I also undetstand that they can do the same by pumping water out of mines then dumping it back down the mineshaft (turbine at the bottom).

Re:Potential Energy of Water

[BamZyth]

You don't really have to pump the water.

In hydroelectricity rich countries like Canada, you can just diminish the flow of water
going through the hydraulic turbines. Less water is used, thus it is still in the reservoir ready
to be used later.

Re:How to get rid of Roland Piquepaille...

[LiquidCoooled]

It can't work that well.
Afterall, you are posting in one of his articles.

Re:How to get rid of Roland Piquepaille...

[HateBreeder]

apparently not well enough.

Stupid idea

[cdn-programmer]

This has to be one of the stupidest ideas launched in a long time.

Electricity is a low entropy energy source. Heat is a high entropy source. The maximum efficiency one can obtain from _any_ heat engine is the sterling cycle and it is limited by the differences in the temperature between the hot and cold energy source and sink.

It is just amasing how little thermodynamics people know. So why is this story on slashdot? It would find a better home in the rags at the supermarket checkouts.

A much smarter idea would be to use the energy to produce yas hydrogen (if we had a place to store it) and failing that even pumping water up to the top of a hill to power a hydro-electric station makes more sense.

Re:Stupid idea

[edittard]

I was thinking along much the same lines, so I read TFA a bit more closely.

Despite what it says, it's got sod all to do with storing energy - more like using some at low demand times to avoid using it at peak times, e.g. by pre-chilling the cold store at night. It's just that the retards who wrote the original article and submitted it don't have a clue between them.

Re:Stupid idea

[Anonymous Coward]

Somebody just got a passing grade on his Thermo final.

Re:Stupid idea

[Anonymous Coward]

I agree, it's impossible to 'store' any energy by cooling something. It just doesn't work.
how do you get back the energy stored in a fridge ?

On the contrary : you can store energy by heating something, then get back a part of this energy but the ratio would be very low (it's again an problem of entropy).

Re:Stupid idea

[hcdejong]

RTFA. They're not storing energy as heat and then attempting to recover it, they're modulating the energy usage of the cold store to buffer the grid. Cool down the store to -25 C during peak supply hours (which often don't coincide with peak demand), and you can switch off the refrigerator and let the temperature rise to -23 C during off-peak supply hours. This is beneficial regardless of whether the grid is powered by wind, solar or fossil fuel plants; wind power is just the sales pitch.

Re:Stupid idea

[Anonymous Coward]

The maximum efficiency one can obtain from _any_ heat engine is the sterling cycle and it is limited by the differences in the temperature between the hot and cold energy source and sink.

Clarification. The Carnot Cycle defines the most efficient heat engine cycle. The Stirling Engine is the most efficient heat engine design and can approach the maximum efficiency defined by the Carnot Cycle.

Re:Stupid idea

[toQDuj]

Actually, your idea to produce hydrogen at the windmills is one of the stupidest ideas in a long time. I was reminded of this by the CEO of NUON, a dutch energy company.

The argumentation goes as such: imagine clean power from windmills. Then imagine an electrolysis machine to produce hydrogen. then imagine a huge compressor, required to liquefy the hydrogen gas. then imagine storage tanks, which will slowly leak hydrogen. These tanks have to be regularly replaced because hydrogen tends to mess up the metal lattice structure, degrading the stability.

Then imagine actually transporting the remainder of the hydrogen across roads (pipelines would lose too much hydrogen), and subsequently converting what's left into electricity.

For your idea to work, we need hydrogen storage materials, which can be loaded and unloaded under more gentile conditions. Look towards metal hydrides for a potential answer there.

B., M. Sc.

p.s. RTFA. please, before you start labeling people as stupid.

Re:Stupid idea

[Anonymous Coward]

No. You are the one who is incorrect. While your freshman physics analysis is correct for someone
who is cooling something down, to later generate electricity from it. That is not what they are
suggesting. your knee jerk reaction shows how a little bit of knowledge can be a dangerous thing,
  when applied incorrectly.

They are talking about storing energy by basically running the freezers when wind energy is available
to compensate for when it isn't. Imagine your refrigerator motor needs to run for 1 hour each
24 hours to keep your refrigerator cold. This is just timing the refrigerator's motor to
run when the wind is out. It's not perfect storage but the cost is virtually "zero" as all we are
doing is timing the motor. In fact if the wind just happened to come up at the same time
the motor would normally come on, it's easy to see that the "storage efficiency" would be 100%

Re:Stupid idea

[sholden]

How do you manage to write when you clearly can't read (or think)?

Re:Stupid idea

[limecat4eva]

"It is just amasing how little thermodynamics people know."

And it is both amazing and amusing that the most condescending pricks are, as in your case, the ones who can least afford to be so.

Hey, mods, this arrogant pissant is still at +5 Insightful? Do your job.

Re:Stupid idea

[radl33t]

Using windmills to generate hydrogen is hardly his idea, but in fact one that currently occupies many research groups with researchers that most people would probably not identify as stupid. As much as I would love to deride the 'argumenation' of your dutch CEO, may I simply point out that there are other methods for completing each and every step in your proposed scenario. I don't understand how you (or he) feel(s) this case is representative of the generic goal of using wind power to produce hydrogen locally. Furthermore, how is it incompatible with the gentile load[ing] and unload[ing] of hydrogen using metal hydrides? Why exactly can't they be incorporated into your hypothetical scheme to alleviate some of the problems you name? Lastly, don't you think it's a bit silly for you to chastise GP for making criticisms based on incomplete information when you do the exact same thing? Branding your post with your degrees in some vain search for credibility is embarrassing.

Re:Stupid idea

[cdn-programmer]

You sure hit the nail on the head! TO bad you weren't modded up.

A misleading way to look at the problem

[Lew Pitcher]

This idea isn't new. My local electricity company has been pushing this sort of thing for years, at the community/household level. Right now, I "store" electricity in my dishwasher overnight, to be released in the morning. That is to say, I run my dishwasher at night, when demand is low and supply is more accessable, and refrain from running it in the day, when demand is high and supply is scarcer. This way, the electricity I /would have/ used in the day can be used by others.

But, that isn't "storing" electricity. And neither is this windpower to cold-storage idea "storing" electricity. Both activities are just /deferring/ electricity use to off-peak hours.

Re:A misleading way to look at the problem

[maxume]

This system has the potential to capture unused off peak power. You can jigger around the accounting to make it look like it is /preferring/ off peak electricity use(i.e, when you make the cold house colder-than-it-needs-to-be, you are using the electricity ahead of time, not later, it never gets 'too warm').

alt fuels and systems

[drDugan]

Very nice. However, we're still just window dressing the Titanic.

500,000 years+ worth of stored energy in oil has been used in 200 years, and will be gone in another 200. Bummer. We found it, and used it. We have 6 billion people now (and growing fast) who want energy -- lots and lots of it.

All the alternative-fuels scenarios - even in the very best case where we grow vast oceans and fields of seaweed and switchgrass and use yeasts to process cellulosic 5-carbon sugars and make ethanol -- even in these best case scenarios (which incidentally would close the carbon loop), humans are still 1-2 orders of magnitude lower in energy production compared to the current oil-fueled system. If we add to that calculation efficiency measures we get closer, lower population - closer still, conservation - still closer... but: the harsh inescapable reality humanity faces in the next 30-50 years is this: there will just not be enough energy for the growing (first-world) population.

http://en.wikipedia.org/wiki/Cellulosic_ethanol
http://bioconversion.blogspot.com/2006/08/celunols -wet-biomass-conversion.html

We need to perfect nuclear power engineering, software, and extremely long term storage processes as soon as possible.

Re:alt fuels and systems

[Grail]

That, or we need to wean ourselves off the high-energy-consumption habit.

Re:alt fuels and systems

[Sj0]

Hydroelectric is cheap, plentiful, and effective. Long before things get THAT bad, we'll likely see a massive increase in hydroelectric power and possibly others like nuclear. With the increased electrical power generated, we should be able to move many of our larger energy consumers over with relative ease.

Re:alt fuels and systems

[deglr6328]

I confess to being baffled as to why people continue to indulge themselves with the delusion that such a proposition as yours will ever be possible. Considering these two graphs how could the prospect of "weaning ourselves off of high energy consumption" ever be seen as anything but irrational hope? No, the exponential growth of energy consumption by human civilization and the inextricably associated increases in life expectancy and living standards are undeniable. The energy consumption of the world will continue to increase exponentially and unabated for the forseeable future. The trick then, is to find a source of energy which can simultaneously provide the staggeringly huge needs of the future while also being environmentally benign. Controlled nuclear fusion, among a few other potential energy sources, fits this need nicely.

Re:alt fuels and systems

[Anonymous Coward]

Most large scale hydroelectric has already been tapped...

Re:alt fuels and systems

[Sj0]

Actually, there are pretty large reserves in a lot of places that can be tapped, but haven't because it's politically unprofitable to do so.

Re:alt fuels and systems

[evilviper]

500,000 years+ worth of stored energy in oil has been used in 200 years, and will be gone in another 200. Bummer. We found it, and used it. We have 6 billion people now (and growing fast) who want energy -- lots and lots of it.

Oil is a convenient PORTABLE energy source.

Only PORTABLE applications will really be adversely affected when we run out of oil. Coal, hydro electric, nuclear, natural gas, wind, solar, etc. will continue to function just fine.

Energy isn't the problem. Inexpensive portable energy is.

We need to perfect nuclear power engineering,

You want everyone to have a nuclear power plant in their cars?

Of course not, this is just a typical straw man.

Re:alt fuels and systems

[Frodo2002]

"We need to perfect nuclear power engineering, software, and extremely long term storage processes as soon as possible."

You have wonderfully and accurately summarized that a) oil production has peaked (although you did not say it that way) b) ethanol cannot save us. So why do you think nuclear energy is the answer? Where is the uranium to run an additional 50 nuclear power stations going to come from? Like fossil fuels, uranium is a finite resource. Sounds like you're still trying to rearrange the deck chairs on the titanic to me.

Re:alt fuels and systems

[Anonymous Coward]

did the OP write fission and we all missed it, or are you trapped in your own context?

Re:alt fuels and systems

[drDugan]

a few thoughts. first off, the real benefit from oil is high energy density (energy/mass) - it is this factor alone that makes it so nice as an energy storage material. most all the alts have much lower ... and of course this is tied closely with portability.

second off, don't underestimate the value of portable. getting all the other resources around and to the right place is a huge problem without trucks or trains or airplanes. It is a enormous luxury to fill up and be able to drive 300+ miles, or fly 3000+ on a single tank, and repeat easily and cheaply.

nuclear in the cars? - you bet! don't hold yourself to thinking fission is the only way.

Re:alt fuels and systems

[Grail]

Energy consumption is not inextricably associated with increased life expectancy: people were living to 100 long before they were using electric toothbrushes. A 100-inch plasma screen TV does nothing to enhance your life expectancy.

The trick is to find a source of energy which doesn't produce heat or chemical pollution when generated or used. Otherwise the energy consumption of the world will come to a horrid, screeching halt as all the industrialised nations turn into deserts and we enter a new ice age.

Re:alt fuels and systems

[deglr6328]

you're dumb

Oookaaay

[iminplaya]

Let me get this straight. The refrigerator is "feeding" the grid because it consunes less from the grid? Because we get some power from a wind turbine, right? Is there some kind of net metering thing going on here? Or is it just simple reduction of usage? Sounds like somebody's playing with words.

Re:Oookaaay

[Anonymous Coward]

Let me get this straight. The refrigerator is "feeding" the grid because it consunes less from the grid? Because we get some power from a wind turbine, right? Is there some kind of net metering thing going on here? Or is it just simple reduction of usage? Sounds like somebody's playing with words.

I dunno, my representatives in government are always calling it "slashing the funding" when the funding for their favorite program continues to go up, just at a slower rate. I'd say that by this logic, these freezers are feeding the grid. :)

Article and post misleading

[AaronW]

I think both the article and post are misleading. Basically all they are doing is turning down the temperature at night and letting it warm up during the day. This just means that most of their energy consumption occurs at night, when there is often a surplus of electricity. It's a great idea though. Many forms of power generation cannot quickly adjust their outputs due to the wear and tear it would cause by temperature changes. I.e. coal, natural gas and nuclear power plants usually run at one output level, resulting in a lot of extra energy available at night when demand is low.

This wouldn't be restricted to just wind power like the article says. It would also be very useful for many other power sources.

One other method I heard about many years ago was to use the extra energy at night to pump water to a high elevation resavoir and during the day use that water to help generate electricity.

Re:Article and post misleading

[Anonymous Coward]

Eh, a nuclear plant can change power level quickly enough to be a propulsion plant for a ship or submarine. I don't think they're burning off extra electric power at night any more than we have to drive in circles really fast when we 'd rather be going slow.

Re:Article and post misleading

[mgv]

I think both the article and post are misleading. Basically all they are doing is turning down the temperature at night and letting it warm up during the day. This just means that most of their energy consumption occurs at night, when there is often a surplus of electricity. It's a great idea though. Many forms of power generation cannot quickly adjust their outputs due to the wear and tear it would cause by temperature changes. I.e. coal, natural gas and nuclear power plants usually run at one output level, resulting in a lot of extra energy available at night when demand is low.

At the risk of being a bit redundant here, this is energy shifting.

It actually increases total energy requirements. Overcooling a thermal store will cause increased losses due to leakage of heat back into the store.

The only benefit is to reduce peak consumption, at the expense of increasing total consumption.

I think that there are probably better energy stores than this.

Pumping water against gravity and flow batteries come to mind as better energy stores.

When we have enough energy from renewables and nuclear to do store the excess, the overall efficiency of the storage is probably going to be better using these sorts of technologies.

There is a natural limit to how much cooling you can do (it tops out somewhere before -273.15 degrees celcius), and the closer to the limit you push things the more leakage you get.

Michael

Re:Article and post misleading

[maxwell demon]

There is a natural limit to how much cooling you can do (it tops out somewhere before -273.15 degrees celcius)

Cooling beyond the boling point of nitrogen (-195,8 deg. C) would already cause major problems.

Re:Article and post misleading

[njh]

We're talking about a variation of 1C at -20C. Assuming an average outside temp of say 10C we're looking at a variation in losses of 3%. You are not going to find a battery, flywheel, fuelcell or pumped hydro system with a round trip efficiency of 97%.

The idea is a perfectly reasonable way to store energy, and the cost per Joule stored is going to be basically nothing compared to any other system.

Re:Article and post misleading

[jbengt]

The real value in shifting consumption to off-peak times is that the utility doesn't have to spend quite as much building new plants to meet the increasing demand. They pass some of this savings on to the customer as an incentive to use available capacity at night. It's not that there's extra energy at night, though there is some excess generating capacity available, it's that there is NO extra capacity avilable on a hot summer day.
And they are doing more than just overcooling at night, they're storing "free" wind energy at night as well as using "free" wind energy during peak times. They overcool when the wind is blowing so that they can allow the temperature to swing a little if the wind dies down during the heat of the day.

Re:Article and post misleading

[mgv]

We're talking about a variation of 1C at -20C. Assuming an average outside temp of say 10C we're looking at a variation in losses of 3%. You are not going to find a battery, flywheel, fuelcell or pumped hydro system with a round trip efficiency of 97%.

Yes, but that is 3% on top of the existing losses. Its a 3% faster loss. It would depend on the loss per hour.

If, for example the losses were 5% per hour then your losses are greater. 5% per hour implies that you would return to essentially to ambient temperature after about two day (90% thermal leak assuming exponential decay). This may be unduly harsh, or it may not, depending on your insulation.

On this basis a 12 hour energy store will lose 40% of its energy.

So, it depends on how well insulated your cold store is.

Michael

Re:Article and post misleading

[Pinback]

Seems like the cooling process would be more efficient while the ambient temperature is lower, at night.

Re:Article and post misleading

[njh]

I'm sorry, I'm not following your maths here. We have a choice - either store the energy in say a battery (with 50% roundtrip), or store it as extra coolth.

Whatever the losses are, the 1 degree change as suggested would result in a 3% change in them (assuming linear heat transfer, a reasonable assumption here). So if 5% per hour results in 1-(1-0.05)^12=0.46 losses in 12 hours then dropping the temperature 1 degree will result in 1-(1-0.05*1.03)^12 = 0.47 loss in 12 hours - 2.2% more. If that energy were stored in a battery it would have resulted in a virtual loss of 50%, in this case we're looking at a virtual loss of 25%. If we take the continuous case (exp) we get a virtual loss of 2.1% (98% efficient).

The fact that the article says that a 1C change is sufficient to keep temps below the required value for the next day suggests that your assumptions are wildly off? I guess that the thermal mass is vastly greater than the losses (time constant) as the time constant increases the efficiency moves towards 1. Consider that you have maybe a thousand tonnes of ice surrounded by a wall of R(metric) 3. Back of the envelop suggests 6kW heat losses and storage of 2.1GJ for a time constant of roughly 4 days per degree C.

Re:Article and post misleading

[mgv]

We have a choice - either store the energy in say a battery (with 50% roundtrip), or store it as extra coolth.

I'm not sure that battery storage is as bad as 50%. If that is your best option for storing energy for 12 hours, then cooling looks good. Somehow I don't think that that is the best case scenario for storage.

Pumped Water energy storage is 70-85% efficient.

Supercapacitator are up to 95% efficient.

That is your reference point for a 12 hour energy store.

I'm not saying that it might not be better to overcool, but just pointing out the options.

Michael

Re:Article and post misleading

[njh]

Pumped water is not really an option unless you have a convenient supply of water and a large mountain or mine system.

Supercapacitors are very low energy density - you'd need a room full of supercaps to replace a Lead acid car battery.

The most important advantage of coolth storage is that it is only a software change - you don't need to buy any new power handling system, just reprogram the thermostat. There are other similar demand management systems - electrochemical smelters can often vary their electricity consumption between 'just staying warm' and 'pedal to the metal' and use vast amounts of electricity. Once demand side metering becomes big, we'll see lots of this sort of mitigation.

Re:How to get rid of Roland Piquepaille...

[robably]

Works well

So... how on Earth did you see this story?

Well, an old idea in new disguise ;-)

[The Terminator]

Well, this usage pattern resembles much the old idea of a pumped storage power plant (Pumpspeicherkraftwerk), a hydroelectric powerplant where the water, which is used in high load times to produce electric power, gets pumped back uphill to a reservoir by use of the excess power of the basic load power plants like coal or nuclear driven ones.
This is done for decades now in the european grid. I had the opportunity in the late sixties to visit such a power plant at Schruns/Tschagguns in Vorarlberg in Western Austria.
It's a very impressive installation with a entire delivery height of more than 2000m (6000ft) in two stages. In the exhibition is also an impressive display of the entire european powergrid.

CU

Fuzzy handwaving

[DerekLyons]

They seem a bit fuzzy on the all-important step of recovering the power from the 'cold store' during the day.

Cold Sores

[tao_of_biology]

Anyone else read that as Storing Wind Power in Cold Sores? Because I was pretty frackin' amazed for a second.

Re:Cold Sores

[adnonsense]

Yes, and I was going to write a post about it with a gratuitous reference to the possible usage of Open (Cold) Sores Software, but you beat me to it.

Re:Cold Sores

[HangingChad]

Anyone else read that as Storing Wind Power in Cold Sores?

ROFL! That was my first read, too. Except my first question was why, which kind of says something because you think it would be how.

Re:Cold Sores

[prestorjohn]

an egg is a ckn's way of makinh another ckn likewise.

All correct. Except the plants shut down.

[HornWumpus]

Would be peakers. Not baseload coal. It's just too bloody cheap not to run.

The first thing shut off/not built would likely be a gas fired combustion turbine.

BTW large customers have been doing this for decades. This story is just slashcrap.

Pumped storage hydro is common world wide.

[HornWumpus]

It really does a number on the fish though.

Pumped Storage and Compressed Air Storage

[rohar]

This idea isn't really storage, it is just lowering usage during peak hours and making up for it in off hours. The idea doesn't seem to align with the mentioned wind power generation. I would think that except for during storms there is less wind at night at most locations, and they are talking about increasing load at night.

Other grid energy storage

Pumped storage could be adapted to wind.
Compressed air storage is another idea. The gas turbine generators have clutches in the compressor section and stored compressed air that is compressed in off-peak hours is used rather than the turbine powered compressor. The existing systems use the gas turbines in off-peak hours to compress air, but I would think that using wind powered compressors in a compressed air storage gas turbine plant would be a simple retrofit.

Re:Pumped Storage and Compressed Air Storage

[mdsolar]

Thanks for these links. This is really helpful. I'm trying to collect ideas on enrgy storage at http://mdsolar.blogspot.com/2007/01/why-renewables -displace-nukes-first.html because this is crucial to converting to renewables. There is a link to a promising flywheel technology there that should be helpful for distibuted storage at http://mdsolar.blogspot.com/2007/01/saving-not-bor rowing.html.

The main article is talking about load shifting rather than energy storage through there is a delta T involved. A number of industries can do this and do when they get discounts. But, at the point where the renewable power sources on the grid can meet total demand at some instant in time, we are going to need a fairly robust energy storage network or else we'll need to leave a portion of the energy unused. This would be a roadblock to making renewables the dominant energy source to further displace polluting energy sources. The traditional way of doing this, using biofuels as storage, could play a big role if we think of these as supplemental rather than replacement sources of energy. I'm not sure I'm saying this clearly: Straight catchem as you can renewables can supply our total energy need while biofuels have an efficiency problem and can't, so it is better not to think of them as a replacement but rather as a useful kluge that can help around the edges. At http://mdsolar.blogspot.com/2007/02/photosynthesis .html I sketch out the relative efficiencies of various biofuels and PV solar power.
--
You can get going with solar: http://mdsolar.blogspot.com/2007/01/slashdot-users -selling-solar.html

Is this really novel?

[ortholattice]

I don't see how this is really that new of an idea. Pre-cooling buildings below normal temperature settings, prior to the onset of peak demand periods when electricity rate is higher, is a standard economizing measure that has been used for years.

Peak electricity demand probably has little relationship to the tiny percent of wind energy injected into the grid - when wind energy is more, the coal/oil/nuke generators just have to use slightly less fuel than they would otherwise, regardless of the demand. As for frozen food warehouses, it would suprise me if they don't already overcool when electricity rates are lower, to save money when the rates are higher, although I don't really know. But the motivation to save money is high enough in the cutthroat-margin food business, and the technique simple enough, that I would imagine this is already being done.

Anyway, I don't see why this has to be some kind of "large scale test". If the percent of wind energy is really so large at night that the grid cannot accomodate the fluctuations, just adjust the differential day/night electricity rates accordingly. Greed will take care of the rest.

Roland the Plogger, wrong as usual. Real facts:

[Animats]

It's Roland the Plogger, wrong as usual, spamming to promote his blog. The Slashdot editors gave him two links this time, one without a "nofollow". Ka-ching!

OK, now the real info. Thermal energy storage has been around for years. There are thousands of installations. It's used when there's a big difference between day and night power rates. During the night, water is chilled, or ice frozen; during the day, the cold water is used for air conditioning. See Thermal Energy Storage Strategies for Commercial HVAC Systems for details on how to configure such a system. Also see CALMAC, which makes such gear. It was a spinoff from their ice-rink equipment business.

Re:Roland the Plogger, wrong as usual. Real facts:

[Anonymous Coward]

Believe it or not Roland's summary probably makes more sense to laypeople than your technical drivel. The analogy serves just fine for this explanation. Slashdot, believe it or not, does include an audience beyond thermal science engineers. If you want to get in an argument about the semantics of heat or thermal energy I'd likely tear your fucking head off given the grossly misleading terminology on the first page of your "acceptable" source. And since this isn't a forum on thermal physics, why not give the benefit of the doubt for a fine summary, your karma whoring aside of course?

I don't see the problem with the submission either. The primary link is Nature. The clever use of thermal reservoirs to augment energy conversion dates back well before the existence of HVAC. This contribution is notable for two reasons, first the size of the endeavor and second the context within our new-age energy systems.

Even without these points, I posit any scientific journal article is a better discussion point than 95% of the microsoft/apple/linux/web2.0/x86hardware/libertari an-psychobabble/ geekboy fluff that flies around here.

What growing first world population?

[HornWumpus]

Where are you getting your stats from? (your butt?)

Re:What growing first world population?

[ArsenneLupin]

(your butt?) That is indeed a good solution against overpopulation!

Re:What growing first world population?

[maxume]

The one in China. (People keep improving their lives)

Re:What growing first world population?

[Anonymous Coward]

The first-world population is not growing by reproduction but by inclusion. The US is the only country with a substantially above-replacement birth rate in the first world, but as the world gets richer the number of places and people described by the term "first-world" is growing fairly rapidly.

Think about all the oil that gets used today. Now think about three billion Indians and Chinese all wanting an American lifestyle in 30-50 years. This is not to say that the problem is insurmountable, but the first world is undeniably growing at a high rate.

Centrifugal storage

[Anonymous Coward]

Why dont they store it in a flywheel? ie., centrifugal energy storage

Cold Confusion

[Doc Ruby]

In other words, Europeans will use wind power to cool large existing refrigerators instead of some fraction of the power currently keeping them cool.

How is this "ingenious"? Even "cool" would be just a lame pun.

How many Can do this?

[JamesTRexx]

I think the question is also how many stores Can do this?
I work in the IT section for the biggest refrigeration company in the Netherlands, and from what I've seen every type of food has an specific storage temperature. Apparently a 2 degrees Celcius difference will make a big difference in the quality of food.

Re:How many Can do this?

[Anonymous Coward]

perhaps an additional wall surrounding the actual storage facility. The outer chamber varies between say -5 and +5, meanwhile the insulated inner sanctum stays roughly 0.

Making green energy from nuclear energy

[Portal1]

This is done a lot in Norway,

There they have double water dams/basins one high one low.
During peak hour the water is rushed down for electricity.
During night they buy cheap French nuclear energy to pump water back.

We called this making green energy from nuclear energy
(btw i am not against this scenario, but the energy is not really green )
Also a lot of energy is lost in the transportation from France to Norway

Better solution, combine it with windmills on the mountain ridges

Re:Making green energy from nuclear energy

[amorsen]

This is done a lot in Norway,

There they have double water dams/basins one high one low.
During peak hour the water is rushed down for electricity.
During night they buy cheap French nuclear energy to pump water back.

I don't doubt that they do this, but I doubt that much electricity from France is involved. The Scandinavian grid and the Middle European grid are not synchronized, so only DC links between them exist (or perhaps AC links with phase regeneration, but does anyone do that anymore?) The amount of electricity that could be moved is rather small -- there has been much talk about increasing capacity, but has anything really happened? In fact, if I read the map on GENI right, the Norwegian power grid is somewhat wimpy and reliant on the Swedish grid. That's the kind of thing you can get away with when you have lots of hydro spread across the country, but not the kind of thing for major energy import/export.

Re:How to get rid of Roland Piquepaille...

[networkBoy]

Simple, he has another browser instance that is an invert of this so he sees only roland stories, thus he can troll them better :-)
-nB

Progressive idealism

[cryfreedomlove]

I hope this works out. I am interested in any invention that provides an environmentally clean method of power generation. The final goal of which is to increase the available per capita of energy. Forget conservation. The true progressive ideal is to find the means to allow for an increase in personal energy consumption.

There are no stupid ideas in Nature, so RTFA

[Anonymous Coward]

The article is talking about storing "cold" which is a form of energy only useful to fridges. There is no claim that they came up with a general purpose form of energy storage.

Expert reaction

[Portal1]

Hi I am running a company that implements a lot of software for most of the dutch electricity company's

There is a special communication protocol used to communicate between these electricity company's
It is called EDINE and is based on EDIEL which is again based on EDIFACT
One of these messages QUOTE-RRV is specifically used to trade over and under production.
But is also used to trade possibility to not consume for a certain time.
Which effectively lowers the demand for a period of scarcity

This is used a lot in aluminum factory's that can effectively shut down for a day when there is a problem in a power plant
Of course if the same can be done for cold stores that is great.

Most of those company's are very wanted by electricity company's and they normally have very lucrative contracts
almost getting there electricity for free.

Hydrogen plants would be also very good candidates

Greets John

We have our firehose...

[Anonymous Coward]

... now blow Roland away, please !

Why Not Just..

[JohnnyOpcode]

Use the windpower to chill the carbon dioxide out of the atmosphere and save the planet. Dump (inject) the 'dry-ice' into deep lakes and even the ocean. Can I have my 25 million dollars now so I can go buy myself a big-ass SUV and play gangster/pimp/hacker/pornstar/politician/monk.

RTFA

[Venerable Vegetable]

Heat engine? Insightful? They're switching the refridgerators off when there's an energy shortage, what does that have to do with entropy?

Re:How to get rid of Roland Piquepaille...

[KillerCow]

Works well

So... how on Earth did you see this story?

I use the script. This is what I see as the story:

This story was submitted by Roland Piquepaille.

not efficient

[FarHat]

Doesn't seem particularly efficient as removing heat from a reservoir is not a very efficient process. Especially when the reservoir is already cold to begin with.

Dune, anyone?

[borfast]

Reading the description in the summary reminded me of Windtraps, the power generators of Westwood's Dune 2. Great game. Those were the days... :)

Re:Centrifugal storage

[Anonymous Coward]

I think I remember reading that there were arguments against flywheels in wind power plants because of fears that the flywheel would need to be large and it might break and fly off and kill/break things, much as people are afraid of the blades doing the same thing since if they're spinning at very high speeds. seems like a pile of idiocy to be afraid of that sort of thing, akin to not building a hydro electric dam because the dam might break. this really doesn't have much to do with anything though, hence the AC.

billing

[jbengt]

You're incorrect.

In my experience (as an HVAC engineer that has to occassionally design around the rates) most commercial/industrial accounts pay more at peak times than off-peak, possibly different rates at different times of the year, and they also incur a demand charge for the peak kW demand of the month. The demand charge is often equal to or greater than the energy use charges, thus encouraging energy storage during off-peak times. Unfortunately, during construction the emphasis is on construction costs, not long-term costs. After all, if they can't build it with the money they've borrowed, it won't get built at all. The fact that it would save money in the long run doesn't appeal to someone who is struggling just to stay within their budget.

Roland Piquepaille of posies?

[Anonymous Coward]

Roland... Piquepaille of posies?

im sorry but it has to be a fake name..... he looks like a sim ...yes, from the game the sims.

This doesn't matter with regard to wind power.

[Tatarize]

Why not just turn the fridges down? If the "food won't melt" then just save the power all the time. If it has to do with deep chilling the food at night to get it through the day. Well, you can do that crap without the wind power. This seems like a complete waste of time. If it works for freezing units to use off peak power, let them do that. Saying wind power, doesn't add anything to the idea.

You see, we have this timed thing to let hot water heaters cool during the night and turn back on at like 4 so that it's ready in time for your shower. We have programmed into it an amazing device which learned and calculates when you typically use your hot water and it predicts it saving energy. So if you went on vacation it would slowly stop giving you hot water (yes I just thought of this, no it won't be worth anything). It's great and wind power is great too.

The plausibility of the idea has nothing to do with wind power.

Re:This doesn't matter with regard to wind power.

[Anonymous Coward]

Not quite nothing. Wind Power is a fickle energy source that can provide at only certain times of day. Nuclear is a stable baseload energy source that would also benefit from this. But we gain nothing if we do this with more variable-capacity power plants.

Re:This doesn't matter with regard to wind power.

[IHC Navistar]

mod parent up!

Re:This doesn't matter with regard to wind power.

[jonbryce]

Yes, they can do this without using wind power, and they probably do. That isn't the point though.

The point is that the output of a wind generator is pretty erratic and unpredictable, and this limits the % of total electricity that this source can supply.

If you have a power input that can take an erratic and unpredictable electricity supply and still function effectively, then this increases the % of electricity that can be supplied by wind turbines.

Re:This doesn't matter with regard to wind power.

[maxume]

Except that there might be wind power available in the middle of the night that is currently getting pissed away into the ether. There isn't really any other power source that happens to have excess capacity available in the middle of the night; wind is generally built as 'peak' capacity, because it might not be there once in a while. This system highlights a way of making sure that the energy gets used when it is available(it is good for the power company to simply 'give' the power to the cold houses, as it reduces daytime demand in a predictable fashion).

Re:This doesn't matter with regard to wind power.

[Ziwcam]

The reason this matters for wind power follows:

Wind power is notoriously unreliable. A coal power plant can be predicted to always give out X amount of energy per minute (hour/day/whatever). Wind power, however, cannot. As weather is wont to do, it changes wildly and unpredictably during any given time span.

This method would allow cold storage units to use wind power to chill their goods during the night using "unpredictable" wind power, causing them to require less conventional power. That's how and why it works, in short. RTFA to figure it out if this doesn't help.

Re:This doesn't matter with regard to wind power.

[pijokela]

Thank you! I finally got what the point was.

Still though: Here, when you make a contract that has a lower night price for electricity, the power company sends your switchbox a signal when the cheap power goes online and another when it goes off. This allows the company to start the night rate at different times for different people so that the rate change doesn't create a huge surge in energy use.

So this could already be implemented in regular households! The power can be erratic since it is used to heat huge boilers and fireplaces that store energy for the next day. I guess, we'll need another article with more facts. Good news for wind power, I guess.

Not news because it's not new

[Kris_J]

The university where I work has a water tower that they chill overnight at off-peak electricity rates. The water is pumped around campus to heat exchanges in each of the buildings in order to run the air conditioning.

Now, if they were storing wind power in flywheels that would be cool.

Cold.....

[IHC Navistar]

You can't store "cold". The concept of 'cold' is just a simpler way to describe a thermal vaccuum - or a 'heat vaccuum. O Kelvin is just the thermal equivalent of a perfect vaccuum. The quantity of heat energy in a given space is what determines how cold-or hot- something is. Heat is the measured energy, and 'cold' is simply the absense of heat. Therefore, you cannot store the absense of something.

Wheather something feels cold or hot to us is measured by how hot or cold it feels. But, regardless of how cold it feels, there is still heat present-evein in ice or frozen ammonia. Heat content only reaches zero at 0 degrees Kelvin.

I'm not a physicist, but I think of the concept of 'cold' or 'coldness' by defining 'cold' as a "Thermal Vaccuum".

Re:Cold.....

[maxume]

You can store the temperature difference; this is why an ice box 'works' and not 'doesn't work'. If you put some ice out in the sun and some other ice in a cooler in the shade, the ice in the cooler will maintain a greater temperature difference with ambient than the ice in the sun. It is only a temperature difference, but it is perfectly reasonable to think of it as 'storing cold', you can even use it to keep things cool or cool them down.

Re:Cold.....

[IHC Navistar]

No..... An ice box works because it removes the heat from inside the box. You are not storing anything. You are removing heat. You are not even storing anything because 'cold' is nothing. 'Cold' is the absensce of heat. 'Cold' is not energy-heat is.

It is not reasonable to think of it as storing cold, because you are not storing anything, no energy or heat. Cold is not a temperature difference-cold is the absence of heat, not the presence of cold. Heat is a temperature difference, because it is the measurement of heat energy, while cold is the vaccuum cause by the absence of heat, and not the presence of 'cold', becuase cold is, again, the absence of heat.

Re:Cold.....

[maxume]

You are describing a refrigerator.

Back in the day, they cut big chunks of ice up and stuck them in a box, to keep other stuff cold. They took a thing that had a healthy absence of heat(the ice, lots of people took it from rivers and lakes during the winter), stored in in a big pile(often under sawdust, it was a decent, cheap insulator), and moved it around(they would deliver it to peoples homes during the summer). The ice is exactly a 'lack of heat' that you can move around and do all sorts of physical things with.

Thermodynamically, it makes loads of sense to base your accounting on the absence of heat, because it gives you an 'absolute zero', but you can do relative accounting(if you want to torture yourself). Day to day, it doesn't matter very much, you can stick 'cold' in a pipe and move it next door, you can pump it into a room(eventually by pumping heat out, but it's all semantics). People find spots to seal or insulate in their houses by finding where the cold is getting in, not by finding where the heat is getting out(there's those semantics again); it works just fine.

I don't mean to trample on the conceptual usefulness of cold as an absence of heat, but it is perfectly possible to create a system of energy accounting that makes 'zero' at 0 C and count everything above it as a surplus and everything below it as a negative quantity, but it is a lot harder to deal with than an absolute system, so no one does it.

Re:Cold.....

[IHC Navistar]

Good point. The article becomes clearer with your concept of a 'Cold Account' of sorts. You could count that as the absense of heat below 0 C as a negative value, adn the opposite as a positive value. My only problem was the use of the term 'cold' as if it were something.

It was kind of like what my mom used to say when I would leave the front door open in the summer: Shut the $@&% door or you'll let the cold out!

It never made much sense to me because I didn't (and still don't) believe that cold is something that could be let out-cold air maybe. But I always have thought of cold as a 'thermal vaccuum'.

Good explaination of your point though! It makes more sense with your idea of 'Accounting'. than the way the article was written and explained.

You're not "releasing" it during peak

[Gothmolly]

You're simply not using it, which, is a small difference, although it doesn't affect what they're trying to accomplish. It's a good idea - pretty darn simple, so it might actually work/help.

The term for this is called "Demand-Response"

[GreyFlcn]

http://en.wikipedia.org/wiki/Demand_response

This is already being done at many high level companies.
Google, for instance, spends half their energy costs on "on peak" power.

If they can do this effectively with refrigerated warehouses, by all means.

Re:The term for this is called "Demand-Response"

[PPH]

Google, for instance, spends half their energy costs on "on peak" power.

So, only do your Google searches between 1:00 and 4:00AM.

Windmills do not work that way!

[dangitman]

Goodnight!

Averaging

[flyingfsck]

Once there are many wind farms, the supply should average out. It sounds like people are trying to solve the wrong problem - to get a more stable supply, build more whirlygigs in more places.

Re:Averaging

[/dev/trash]

Think of the birds!

mnb Re:Article and post misleading

[Anonymous Coward]

Ever so slightly different scale and cost tolerance.

Brilliant???

[the eric conspiracy]

How is this a brilliant idea? Using off wind generated power for thermal applications like this as well as charging batteries, pumping water uphill to a resevoir, etc. to even out the varying power available from the wind has been around since the invention of the original windmill around 200 BC. Talk about prior art!!!

Nice Implementation of Older Idea

[BookRead]

I actually live in a building from the mid-80's that was built to use off-peak electricity. We got (and still have) a Time-of-Day electric rate where the we pay much less for the off-peak electricity. The ceilings in our units were designed as air plenums and were stocked with eutectic salt bags that change phase at about 68F. The idea is that that, in the summer we "freeze" the salt solution during the evening but cooling the air plenum. During the day we avoided running the A/C and saved significant electric costs. It works in reverse during the winter. They kept the apartments quite comfortable.

Eutectic salt solutions have been used in a lot of commercial applications to store "cold" generated during cheaper energy periods. The main disadvantage is that the eutectic salts break down over time and lose their phase change characteristics. There are also kind of expensive to replace.

Strategies like this that use thermal storage to modulate electric demand are pretty efficient ways to lower the required peak capacity of electrical systems. Other schemes like pumping water back up hill tend to run afoul of thermodynamic laws and can't be nearly as efficient.

Mostly ludicrous

[Ancient_Hacker]

Kinda ludicrous idea.

First of all, if you cool off the fridges, the increased temperature difference between inside and outside the fridge increases the rate of heat loss.

Next the larger the termperature difference, the greater the load on the compressors and the lower the overall efficiency. Although it helps a bit if it's cooler outside at night. But they're already capable of taking advantage of this without any "Night Wind" project babble.

The larger warehouses have more activity at night-- therfore more heat losses. The least best time for having a lower temperature.

A better approch would be to give somewhat lower rates for night electricity usage. Many industries use a *lot* of electricity and could save big bucks by shifting to nighttime work. There's one big steel-mill in town here that uses about 30% of all the electricity-- they'd love to get a few percent off their $13 million per month electric bill by using their electric arc furnaces at night.

Wind power = not good

[Anonymous Coward]

Surely you've heard about how nuclear energy was going to produce electricity "too cheap to meter". What they didn't count on was the problem of waste.

And now we've got wind power that will reduce our need for fossil fuels. What they're not counting on is the effect on the weather. If we start taking gigawatts of power from the wind, what will that do to the environment of this planet? Of course it will change it - wind is more than just "there". It carries heat and seeds - it cools and populates. And probably more that we don't understand.

Small amounts of wind power are useful. Large amounts are dangerous.

Re If we had a place to store it

[cdn-programmer]

I guess you can't read.

If we had a place to store it

I am perfectly aware of the difficulties with hydrogen storage. This is why I commented "If we had a place to store it".

alternative cooling

[rossdee]

Or you could just open the doors at night and let in the below 0F, and shut them during the day when its warmer outside. (well that would work here in the midwest in winter)

a more general solution

[drDugan]

A more general solution is to have the price of electricity usage reflect actual hourly demand. This will create incentives for all electricity users to time shift usage to lower demand time periods if possible.

There is an overhead to this solution in that the metering then needs to be much more precise than current methods. We now meter as an aggregate over about a month. We would need to meter, aggregate, and report energy usage over small increments, like 15-60 minutes blocks to make this work.

Once we have IP over the power lines - maybe it will be a simple thing to have the electric meter report ones usage more often. But talk about privacy issues!

Re:a more general solution

[cbacba]

Please note that we've had powerline carrier mechanisms including remote meter reading for years and years. IP or any broad band over power line is a giant disaster, economically and environmentally. It creates massive RF interference because unshielded wire is no way to send RF. Essentially, it's generated interference everywhere it's been tried. 60hz (and 50hz) noise is the price we must pay for electricity in the first place. It pervades everywhere and is a pain to deal with on designing virtually every piece of electronics in existance. The BPL crap extends that sort of problem up into the RF spectrum, potentially causing interference to radio and tv stations as well as emergency frequencies for first responders.

It is an idea which is undesirable, causes severe problems and is a more expensive solution with inferior results compared to existing alternatives. To get to this stage, the FCC has had to ignore both its own prviously established regulations and its basic mandate.

The sooner that fiasco dissappears, the better off the human race will be.

Re:a more general solution

[Anonymous Coward]

wow. talk about the power of marketing! your points seem very reasonable.

now I'm not sure who to believe.

I guess, like always, I'll have to do my own research.

can you site additional sources for more information?

actual stored wind energy project

[gumbi west]

I had thought it was this project that actually stores off-peak power and then uses it during peak. It works based on this technology but uses wind power so that the variability can be managed.

Re:actual stored wind energy project

[StikyPad]

I store wind in my large assortment of windbags. I keep them all well protected in a very large domed building discreetly situated in Washington, D.C., whose exact location I cannot disclose for obvious security reasons. I've even had the cooperation of Google Maps in blurring the image of said warehouse.

Fuel cell storage

[mcostas]

Another alternative that is easily envisioned is using a time-varying energy source (wind/solar) to generate electricity for producing hydrogen via electrolysis. Then the hydrogen is stored and can be used at any time in fuel cells. Sure there is some loss, but it's 100% clean and on-demand power.

Then read his comment again, and ..

[WindBourne]

the /. article that showed nicely what a losing proposition H2 is. All in all, there is no efficient way to use hydrogen, even if you had the perfect storage system. In fact, nearly all the other methods of energy storage (including some of the heat ideas) will work better than H2. The only reason why it is pushed by ppl such as W. is that the oil companies will simply strip the H2 from oil (and somehow get rid of the carbons).

Not entirely accurate

[WindBourne]

A number of studies have shown that Wind alone can power all of America (and I believe the world). Of course, that it for today. Throw on that, all the tidal, wave, solar, geo, and hydro-power and we should be in good shape ASSUMING that we do something about proper storage.

Now, with that said, I think that it is a big mistake to move all of our societies to just alternative. I am a big believer that we need to bring on nukes in a big way. In particular, if we are going to go to other planets, it will not be by solar (or any of the other alternative power). It will be by Nukes. The simple fact is, that to colonize a planet, such as Mars, it will require LOTS of energy. In fact, it will require 100x / person what we do today. Efficient Nukes will be everything to being able to move forward.

Finally, we are in the position that we are because we developed just several types of power; Oil, Gas, and Coal. France is in Good shape because they make heavy use of nukes. Greenland is about to be in good shape because they will make heavy use of Geo. But France is at the mercy of others for their fuel.

Jello

[Surfer51]

For those of you who don't understand how the intangible electricity can be stored in cold storage, allow me to explain. 1. The coefficient of elasticity of Jello to the point of diminish and return stored in giant containers of jello... 2. Is equal to the mass of demand released from the quivering jello when the wind is still. Red Jello is almost always used in the Netherlands.

my question is...

[louden obscure]

"to store electricity created from wind in refrigerated warehouses used to store food."

does windmill generated electricity spoil faster than other types?

Too late

[Anonymous Coward]

Our company's refrigerated warehouses are operating on electricity from grid only when it is cheap. If those guys come to us we can only say, sorry, we've already done that. We also have our wind turbines and I believe most refrigerated warehouses in our area also have it.

Strip the H2 from the oil

[cdn-programmer]

This idea is patently absurd!

We have a HUGE hydrogen shortage.

In fact the only reasonable way we can make the hydrogen we need is to build abotu 75 nukes here in Alberta. I am perfectly prepared to back this up.

Here in Alberta we are trying to ramp synthetic crude production to about between 3 and 4 million barrels per day. For each atom of carbon we mine, we need to find an atom of hydrogen. If we can't find the hydrogen we can leave 1/2 the carbon in a waste heat or burn the carbon - thereby losing a significant amount of what we mine in the form of CO2.... the later idea is the Fischer-tropche process.

If we use F-T we produce CO2 in quantities that are measured in millions of barrels of liquid CO2 per day.

In the past, H2 was produced from methane. If you have lots of methane this is a cheap way to do it.

But North America peaked in Methane production in January of 2001. We have a shortage of methane too... and as a consequence, a major percentage of the fertilizer industry in North America shut down. If the plastics feedstocks industry has not also started this shutdown process, then they will... because they will be next (probably). The glass industry is also in jeapardy.

Dont' for a minute think that the "oil industry" is going to just "strip the H from the O&G"! The truth is the oil industry is in dire need of H2... So the idea of using a wind mill to create H2 is acutally a good idea.

Here in Alberta we would need so many windmills to produce the energy equivalent of 75 GIGAWATTS of H2 per DAY that I have no idea where we would park them.

I would probably prefer windmills to nuclear plants.... This is just a personal feeling. But I don't know how we can do it.

We really don't have enough land in Alberta with good wind resources to be able to plant the number of windmills we need. Alberta is a big place.

The short of it is... don't count on the oil industry to produce the H2 you commented on. It ain't gonna happen.

Condescending prick?

[cdn-programmer]

You undertake a personal attack on me in public? And call me an arrogant pissant?

I think when you point a finger there are 4 pointed in your direction.

What do you mean by "least afford to be so"?

Not only did they refuse to mod up...

[Tatarize]

They modded you 'troll' for saying it.

Re:Not only did they refuse to mod up...

[IHC Navistar]

how in the hell did that happen?! Kinda ironic that giving someone props was a bad thing.....especially on SlashDot where viewpoints are supposed to be freely expressed.

Uh-oh.....

I hear my karma slipping because I criticized some crotchety old SlashDot 'moderator'.

Hypocrites.....

Thankyou!

[cdn-programmer]

Yup. Thankyou.

All you need is timer/thermostat.

[Kadin2048]

So this could already be implemented in regular households! The power can be erratic since it is used to heat huge boilers and fireplaces that store energy for the next day. I guess, we'll need another article with more facts. Good news for wind power, I guess.

Yep. It absolutely could. Really, all that you'd need in order to do this, would be a programmable thermostat on your freezer, just like the furnace/AC ones that let you set a different temperature during the day than for when you're around in the morning and evening.

Assuming you know what times the electricity is cheap and when it's expensive, you could just turn the thermostat down, cooling the freezer extra cold, when power was cheap, and then set it back up higher when electricity is expensive. The "cheap cool" you bought earlier (say during the night) would allow you to use less power when it's expensive.

Now, it probably wouldn't really be worth doing with a residential food freezer, but with a grocery store's cold case, or certainly a refrigerated warehouse, it could mean serious savings with minimal equipment.

You might be able to do the reverse with hot-water-heaters, too, although there you'd need to make sure there were some safeguards to prevent scalding (if your hot water heater heats to 190F at night due to the cheap power, so it can 'coast' down to 110F during the day, you might get a nasty surprise if you ever tried to take a late-night shower).

Re:All you need is timer/thermostat.

[An Onerous Coward]

Most water is heated by gas, not by electricity. So the hot water thing might not work well.

Assuming you know what times the electricity is cheap and when it's expensive, you could just turn the thermostat down, cooling the freezer extra cold, when power was cheap, and then set it back up higher when electricity is expensive.

That's a pretty restraining assumption. It's also possible that the energy savings just aren't worth the effort, if done manually. Given that we've gotten very good at automating things, why not turn that talent to this problem?

One thing to remember is that household fridges don't trap their heat very long (certainly when judging by the scale of several hours). So in order to get such small devices in on this "usage shifting", they'd need to be actively receiving information on much shorter timescales. This, in turn, requires that the energy grid communicate with attached appliances. There is a fair bit of research going into smart grids and smart appliances (though I'm not terribly familiar with it).

The point is, if you knew that you could save yourself half a penny of electricity by turning your fridge's thermostat down now, and back up in three minutes, you probably wouldn't bother. You wouldn't even bother subscribing to a news feed that offered such marginally useful information. But give the appliances themselves that information, and everyone saves like crazy.

Wind strongest at day, not night

[plzdontspamme]

Here in the US midwest, the daily time of peak winds coincide closely with that of peak demand. The summer winds are usually strongest during the hottest part of the day, due (IIRC) to differential heating of the surface of the earth. At night, the winds are much lower (often calm).

Re:Compressed Air Storage

[rohar]

I did a drawing of the Compressed Air Wind Electrical Generation System idea.

Re:Compressed Air Storage

[mdsolar]

Looks good. I wonder how ofter the resevoirs are available, or if they can be easily escavated.

Re:Compressed Air Storage

[rohar]

The above example uses an abondoned mine for compressed air storage, but the technology used to create Natural Gas Storage caverns has existed for a while.
In a location with salt,limestone or sandstone rock formations, they are dug with non-potable water injection (at 1100m) and pumping the slurry. NETL has a bit on Rock Storage Caverns dug in areas where the geology doesn't allow for water slurry construction.

I used to work for TransGas and they operate 901 million cubic meters of gas storage facilities. I toured the cavern facility at Regina, SK Canada a few years ago, it's a few miles from my house.

I sleep like a baby on a -20C winter night knowing there is 3 or 4 Penta Joules of gas tucked away there. :)

Re:Compressed Air Storage

[mdsolar]

Now were getting back to the original thread, using refridgeration. The Baltimore-Washington installation wants to cool the gas to reduce pressure specs. Now here is a wild idea, suppose we use CO2 as the working fluid. I was thinking about this for carbon sequestration in the late eighties though I'd have taken advantage of the low brightness temperature of the sky over Antactica. If you store CO2 as a cold solid, you could recover energy in two steps. 1) Use a sterling engine to transfer heat to the solid then 2) Once the solid has sublimated use the pressure to drive a turbine. You would probably want to boost the turbine the way you propose so there is a need to feed in both oxygen and fuel. Recapturing the CO2 would require a big volume I think, but it would not have to be under pressure, in fact you would not want it under pressure at the turbine output. Perhaps a blader would do. When the wind blows then the blader is deflated and the dry ice reformed. This keeps everything at low pressure except the feed in to the turbine where the sterling engine acting as a heat pipe. I'm not so good as you are at making drawings, but I see a big radiator for the warm side of the sterling engine extending into the turbine output, the dry ice fed to a chamber at the cold end of the sterling engine. The chamber acts as a stop valve. Once sublimates, the CO2 runs in to the preheater along with fuel-air mix as you've drawn. To return the CO2 to solid you refriderate it with wind power. You'll want to let off the nitrogen that came in with the fuel air mix, water formed through condensation can be drained off for another use, and extra dry ice can be shipped to wherever it might be useful.

There are a number of other phases for CO2 mixed with other things, here's a phase diagram: http://en.wikipedia.org/wiki/Image:CO2HydrPhaseDia gram.jpg. I don't see anything that jumps out at me here though. The main thing about the solid is low volume and low pressure for storage, though you still need a large volume to retain it once it is sublimated. And, if you don't keep it, you waste a lot of energy cooling nitrogen, oxygen and argon.

where's step 2 : get electricity?

[Ace905]

I've read this article about 5 times now, and I must be totally retarded. Where in the article does it explain how refrigerators actually act as batteries?

It looks to me like they're talking about 'conserving electricity' which is far different from turning a refrigerator into a large battery. For example : if I unplug my fridge, how do I make it start producing electricity?

Maybe they _are actually_ talking about turning fridges into power-cells, but it would be excellent if they could explain where the conversion back to electricity comes into play. If it does at all.

---
must be totally retarded ...

Uranium prices

[g.a.g]

Before you declare nuclear to be the end-all of things, have a look to this graph, showing a seven-fold increase in uranium prices during the last four years. Essentially the same thing that happened to the oil price. Out of interest, how many percent of running cost of a nuclear plant is fuel? For wind, it's zero.

Of course, there's the long-term option of fast breeder reactors and fancy new technology, but I have yet to see a proposal that makes them economically viable - against wind power, that is. Or even gas.

Wind climate

[g.a.g]

Actually, the behaviour of wind and load that you describe makes me believe that you don't know the climate of The Netherlands. Air conditioning is seldomly used there, as temperatures rarely rise over 30 degC, so the peak consumption is in winter mornings and afternoons/evenings. Which coincides (on a monthly scale) nicely with the wind production, which is driven by the North Atlantic lows and not by some thermal coastal effect as in more southerly (subtropical) climate zones.
Actually, what I describe here is valid for most of Europe, including northern Spain (except that they use air conditioning there).

While the whole idea is just peak shifting, for all practical purposes it's a large battery for electricity implemented in a few lines of software. That's what's making the project so interesting - and the sheer amount of refrigerated warehouses in Europe.

Re:Wind climate

[Bloke down the pub]

Air conditioning is seldomly used there, as temperatures rarely rise over 30 degC, so the peak consumption is in winter mornings and afternoons/evenings.

So nobody in the Netherlands uses power tools or electrical machinery (including them there typewriter-TV doohickies) at work, or rides electric trains/trams to get there and back?

While I agree that the climate is pretty dire there, there's more to power consumption than air-conditioning - which you seem to have an obsession with.

Re:Wind climate

[cbacba]

I tend to view things from the perspectives of southern Texas where there is already efforts underway to establish wind farms off the coast and it seldom drops below 30c for much of the year during daylight. However, my view of consumption is more based upon the nature of solar radiation intensities which peak around midday - at least below the arctic cirle and the fact that the vast majority of people work indoors during the day.

I live in a rather unique house which includes four inches of special insulation in the walls. It's major use is in small commercial walk-in freezers using five and a half inches worth of the material. It's not the only insulation in the walls either. Here, we describe the climate as balmy with 6 weeks of fall, 6 weeks of winter, 6 weeks of spring and 9 months of rather hot summer which seldom drops to 30c during the day and sometimes not even at night. Fortunately, it seldom goes over 38c.

I attempted to avoid the direct question of whether it was a good idea to generalize the notion of energy storage into thermal. After all, both hot and cold are readily available in locations not too far away but still a bit too expensive for practical exploitation as energy sources. It would seem that other approaches such as raising water to above a hydroelectric dam would be more effective.

Of course, the simple time shifting of use - assuming the losses due to increased heat flow are acceptable - does make good sense, enough to make me wonder why it wasn't being done all along, at least by some reasonable fraction of that industry. After all, in commercial environments that use a great deal of electricity, there tend to be different charges for usage during different times - to push companies into shifting off loads.

I still don't quite understand why the peak loads would be shifted off of midday so much. I would not expect there to be much electrical heating in that climate nor would I expect the work patterns to be that far off.

The load shedding I described is not done around here. It is done in some states in the deep south and I've also seen it done by some utilities in Minnesota. It seems to be more the nature of the power industry in the region than the location and weather patterns associated with the region.

Your post indicated involvement in climate study. If so, you might be interested to know we are in our typical sunspot minimum climate right now. It's been quite cloudy, significantly rainy, and consequently, somewhat cooler than average. The weather here gets blamed on el nino and la nina in the pacific, but here it tends to track fairly well with the sunspots with few clouds, warmer temperatures and sometimes serious long term droughts, alieviated infrequently by hurricanes and strong wet pacific cold fronts. Then again, this is a desert and it is a bit unsettling to see water lillys growing among the cactus.

Economy 7

[slim]

A more general solution is to have the price of electricity usage reflect actual hourly demand. This will create incentives for all electricity users to time shift usage to lower demand time periods if possible. The problem with that is that it makes things difficult for consumers. A domestic customer is going to get horribly confused if the price of their power varies hour by hour based on actual usage. Assuming electricity costs enough for me to account for it, I want the cost of running my oven for an hour to be predictable.

As early as the 1980s, my parents were on a scheme called "Economy 7": the normal price per KWh was much higher, but you got heavily discounted electricity for 7 off-peak hours at night. Grants were available for storage heaters.

The problem was, the scheme was too successful. The seven hour "off-peak" slot became a peak slot because so many people were charging up their storage heaters. What followed was an adapted scheme where your cheap 7 hours where at one time of day for a two week period, while another group had a different 7 hours. Every two weeks the groups would swap slots. You got sent a wall calendar with your slots marked on it. A radio signal told your meter and your storage heater timer what times to use - so heating was pretty much set-up-and-forget -- but my parents keep in mind whether they're on or off peak before heating water for a bath. ... and that's about as complicated as I think you can get away with in a domestic environment.

Commercial power is another matter. I can well imagine companies willing to go onto very complex tariffs if they can monitor the price and adjust the timing of their high-power tasks to when power is cheap.

Re:Economy 7

[drDugan]

sorry, things already are difficult. we're running out of energy to support the way we live.

don't leave complex choices to the people - make their machines do it.

giving consumers more information will empower them, and empower product manufacturers to make devices that work better within the whole system. All the consumer/product needs are two numbers: current price, and current usage

price is real time dollar per kilowatt hour for energy, and usage is real time energy rate delivered to the unit (the house, the fridge, the heater, etc.) let the geeks figure out how to meter, timer, track and plot the numbers, and work them into the control systems for teh devices. some items will not care - others that can make changes will. If you have consuption-aware, price-aware appliances that can take advantage of those numbers - all sorts of efficiencies can happen. big condo water heaters keep the water temperature up at night and let it bleed down during the day. freezers cool at off peak hours. home control systems choose to water the lawn at the right time.