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Power Science

Storing Wind Power In Cold Stores 242

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."
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Storing Wind Power In Cold Stores

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  • Roland Piquepaille (Score:4, Insightful)

    by suso ( 153703 ) * on Saturday February 10, 2007 @04:16PM (#17965536) Journal
    Um, what the hell? This guy has a spot on ZDnet now? At least we know what he looks like.
    • Re: (Score:3, Insightful)

      by solevita ( 967690 )
      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: (Score:3, Insightful)

      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

  • April yet? (Score:4, Funny)

    by flyingfsck ( 986395 ) on Saturday February 10, 2007 @04:16PM (#17965550)
    Man, time flies. Refrigerating electricity - hmm, wonder how long it will last till it spoils?
    • Re: (Score:3, Informative)

      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

    • by mikael ( 484 )
      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.
  • by The Dobber ( 576407 ) on Saturday February 10, 2007 @04:19PM (#17965576)

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

    Wow.

    • Re: (Score:3, Informative)

      by peterofoz ( 1038508 )
      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 (Cali
      • by caseih ( 160668 ) on Saturday February 10, 2007 @06:33PM (#17966942)
        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: (Score:3, Informative)

      by 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 [idahopower.com]
    • 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: (Score:3, Insightful)

      by alshithead ( 981606 ) *
      "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.
    • I had thought it was this project [wapa.gov] that actually stores off-peak power and then uses it during peak. It works based on this technology [wapa.gov] but uses wind power so that the variability can be managed.
  • 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.,
    • 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.
  • by macadamia_harold ( 947445 ) on Saturday February 10, 2007 @04:20PM (#17965580) Homepage
    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"?
  • by Reverse Gear ( 891207 ) * on Saturday February 10, 2007 @04:20PM (#17965584) Homepage
    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.
    • by Rich0 ( 548339 ) on Saturday February 10, 2007 @04:48PM (#17965866) Homepage
      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.
      • 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...
      • by Anonymous Coward on Saturday February 10, 2007 @06:27PM (#17966888)
        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 [energy.com.au] 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.
      • by sploxx ( 622853 )
        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 kin
      • 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 sys

        • by Rich0 ( 548339 )
          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 peopl
      • by radtea ( 464814 )
        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 loca
        • by Rich0 ( 548339 ) on Sunday February 11, 2007 @07:41AM (#17971440) Homepage
          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.
    • by v1 ( 525388 )
      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.
  • by Dachannien ( 617929 ) on Saturday February 10, 2007 @04:21PM (#17965592)
    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.
  • 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
  • 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 gro
    • Re: (Score:2, Interesting)

      by Dahan ( 130247 )

      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'.

    • It really does a number on the fish though.

    • Re: (Score:2, Informative)

      by gtdawg ( 1062514 )
    • 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: (Score:2, Informative)

      by mccdyl001 ( 808761 )
      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 [google.co.uk]) up to the top of a nearby mountain (link to it on google maps [google.co.uk]. 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
      • ... 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

    • 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 [randwater.co.za]. 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
  • by drDugan ( 219551 ) * on Saturday February 10, 2007 @04:43PM (#17965800) Homepage
    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 [wikipedia.org]
    http://bioconversion.blogspot.com/2006/08/celunols -wet-biomass-conversion.html [blogspot.com]

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

    • by Grail ( 18233 ) on Saturday February 10, 2007 @04:52PM (#17965906) Journal
      That, or we need to wean ourselves off the high-energy-consumption habit.
      • 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 [ufl.edu] graphs [rm.cnr.it] 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 c
    • by Sj0 ( 472011 )
      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.
    • 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
    • 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.

      • by drDugan ( 219551 ) *
        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
    • "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 dec

  • Oookaaay (Score:2, Insightful)

    by iminplaya ( 723125 )
    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 [wikipedia.org] thing going on here? Or is it just simple reduction of usage? Sounds like somebody's playing with words.
  • by AaronW ( 33736 ) on Saturday February 10, 2007 @04:43PM (#17965808) Homepage
    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.
    • by mgv ( 198488 )
      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
      • by njh ( 24312 )
        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.
        • by mgv ( 198488 )
          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 tempe
    • by Pinback ( 80041 )
      Seems like the cooling process would be more efficient while the ambient temperature is lower, at night.
  • by The Terminator ( 300566 ) on Saturday February 10, 2007 @04:47PM (#17965856)
    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
  • They seem a bit fuzzy on the all-important step of recovering the power from the 'cold store' during the day.
  • Anyone else read that as Storing Wind Power in Cold Sores? Because I was pretty frackin' amazed for a second.
    • 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.

    • 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.

  • by rohar ( 253766 ) * <bob.rohatensky@sasktel.net> on Saturday February 10, 2007 @05:03PM (#17966036) Homepage Journal
    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 [wikipedia.org]

    Pumped storage [wikipedia.org] could be adapted to wind.
    Compressed air storage [pennnet.com] 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.

  • 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.

  • by Animats ( 122034 ) on Saturday February 10, 2007 @05:05PM (#17966054) Homepage

    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 [pge.com] for details on how to configure such a system. Also see CALMAC [calmac.com], which makes such gear. It was a spinoff from their ice-rink equipment business.

  • 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.
  • by JamesTRexx ( 675890 ) on Saturday February 10, 2007 @05:15PM (#17966156) Journal
    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.
  • 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.
  • Expert reaction (Score:4, Interesting)

    by Portal1 ( 223010 ) on Saturday February 10, 2007 @05:28PM (#17966304) Homepage Journal
    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

  • 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.
  • 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 [wikipedia.org] that would be cool.
  • Cold..... (Score:2, Informative)

    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 co
  • 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.
  • 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!!!

  • 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 e
  • Mostly ludicrous (Score:3, Insightful)

    by Ancient_Hacker ( 751168 ) on Saturday February 10, 2007 @07:42PM (#17967430)
    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.

  • 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 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

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