Batteries

Published on September 28th, 2014 | by James Ayre

71

Tehachapi Energy Storage Project — SoCal Edison Opens Largest Energy Storage Project In North America

September 28th, 2014 by  

The Tehachapi Energy Storage Project — the biggest battery energy storage project to date in North America — has now opened.

The 32 MWh battery energy storage system built by Southern California Edison (SCE) comprises lithium-ion batteries from LG Chem stationed in a special 6,300 square-foot facility at SCE’s Monolith substation in Tehachapi, California.

Sce

The project was built in that location owing to its proximity to the Tehachapi Wind Resource Area — which is expected to produce up to 4,500 MW of power from wind energy infrastructure in the area by the year 2016.

The project was funded with a combination of the SCE’s own funds and federal stimulus money obtained from the Department of Energy via the American Recovery and Reinvestment Act of 2009.

Explaining the purpose of the project, the DOE’s energy storage program manager, Dr Imre Gyuk, stated: “This installation will allow us to take a serious look at the technological capabilities of energy storage on the electric grid. It will also help us to gain a better understanding of the value and benefit of battery energy storage.”


 

The press release provides more:

The project costs about $50 million with matching funds from SCE and the DOE. Over a two-year period, the project will demonstrate the performance of the lithium-ion batteries in actual system conditions and the capability to automate the operations of the battery energy storage system and integrate its use into the utility grid.

Primary goals of the project are to demonstrate the effectiveness of lithium-ion battery and smart inverter technologies for improved grid performance and to assist in the integration of variable renewable energy resources like wind and solar power.

The battery system supplied by LG Chem is comprised of 604 battery racks, 10,872 battery modules and 608,832 individual battery cells – the same lithium-ion cells installed in battery packs for General Motors’ Chevrolet Volt.

Over the next few years, if the project proves a success, we can hopefully expect to see a larger rollout of battery storage technology solutions on the grid-scale level.

Image Credit: SCE





Check out our new 93-page EV report, based on over 2,000 surveys collected from EV drivers in 49 of 50 US states, 26 European countries, and 9 Canadian provinces.

Tags: , , ,


About the Author

's background is predominantly in geopolitics and history, but he has an obsessive interest in pretty much everything. After an early life spent in the Imperial Free City of Dortmund, James followed the river Ruhr to Cofbuokheim, where he attended the University of Astnide. And where he also briefly considered entering the coal mining business. He currently writes for a living, on a broad variety of subjects, ranging from science, to politics, to military history, to renewable energy. You can follow his work on Google+.



  • Joseph Dubeau

    The current price of lithium-ion batteries prices don’t make it economical for grid storage. A giga factory isn’t going change that, not until prices fall below $100/kWh.

    We could talk about used EV battery packs, but until enough used battery packs become available there won’t a be practical solution anytime soon.

    • Bob_Wallace

      Musk has said that the materials in a lithium-ion battery cost less than $100/kWh. And he thinks that with high enough volume production prices will fall somewhere close to $100/kWh.

      The way to get from where we are now to the minimum possible is by increasing volume. And that’s what Tesla’s gigafactory is designed to do. Crank out a lot of batteries, very efficiently.

      Lithium-ion batteries, at their current price, seem to be forcing their way onto the grid. They can perform some of the role that fossil fuels have been doing. They’re just not yet to the mass storage price level. And other storage technology might beat them out. (Which would be fine. The cheaper, the better.)

      • bink

        bob, prices are not everything and nothing is free so there is always going to be a cost. Other technologies will have price drops as well but they don’t have to be the lowest price to be the technology of choice, they have to have more functionality, longer life and wider application range then, cost effectiveness drives the decision.

        If I am a 3rd party vendor trying to sell a service or system to a (utility) customer in this case, and trying to maximize my profit, I would likely look to promote a technology that can perform both energy and power applications as compared to one that would do either or, though , cheaper.

        you would run an analysis but capacity payments are a lot more lucrative than ancillary payments. .

        using lithium as an example, it would be limited to ancillary services due to the fact it lacks the functional requirements to perform bulk storage, it is a (one dimensional) piece of equipment that needs innovation but I am afraid to tell you and others that the charge discharge ratios are inherently limited and will never be overcome,
        All you can do is add more batteries and that becomes cost prohibited but you still have the degradation issue when using for certain appications

    • bink

      thank you someone, who knows, what they are talking about. no amount of price drop can substitute for degradation and a lack of functionality for some applications. if we are discussing ancillary services, yes they are a solution but even then you have to worry about environmental operating conditions

      • vensonata

        Grid storage is only one way to go, personal storage is another and it seems to be taking off like a rocket in Germany. There are joys in being grid independent under many circumstances. More or less it is like the public transport vs private car. As you see, cars, though more expensive still have great appeal. Most people in the west have grown up dependent on the grid but if it is convenient enough they might like their independence through personal storage.

        • bink

          you are correct, personal storage is a place where it would sit well, but i don’t want people think they are going to run on their li ion batteries for 8 hours and not have to make a huge investment, there are cheaper alternatives that can get them through the nite using all of its capacity. I tend to talk commercial and grid when discussing these things

          • vensonata

            Bink you say “there are cheaper alternatives”. I need a new battery bank by the end of the month, and not just for 8 hours a day, but for at least 3 days storage. Lead acid is cheapest by far, but maintenance heavy and who likes acid? Absorbed glass mat are twice the cost, but maintenance free. Lithium packs are one and half times the cost up front of AGM but have three times the cycle life…but, who knows if they are reliable. If they become unbalanced who’s going to fix them. So it is a little early for lithium residential off grid. But unless Vanadium shows up,( and I have been inquiring for 8 years now) the only contender is …. Lifepo4 (lithium for you non- geeks) So $8000 is soon to be spent…Agm is the winner.

          • Bob_Wallace

            Are you perhaps overstating the maintenance required for lead-acid? That’s what I’ve been using for over 20 years.

            Maintenance requires pushing a button once a month to initiate an equalizing cycle and topping up the water every three months. I also clean the terminals and battery tops when I refill.

            If there’s any obvious problem with corrosion on a terminal I brush it down with some baking soda dissolved in water and then wash off the battery tops.

            This is a half hour or less job four times a year for 12 batteries.

            The first year I checked water levels every month until I was certain that I needn’t bother checking that often.

          • vensonata

            Don’t you sometimes find little holes in your clothing from the acid? Yes, the price at half the cost of Agm is tempting. I could do 100kwh for 10 grand. But since I am not going to water them, somebody else will have to constantly be taught how, then there is the fear factor, the crazy health factoids etc. so I think it is different in a community where people are coming and going than a residential situation. But hey, I may buy a small lithium pack as a side experiment to see how they work and in 7 years when the AGM dies I think the lithium will be a no brainer.

          • Bob_Wallace

            I never have. Once in a while I’ll feel a tiny hot spot on one of my hands but I’ve never noticed even a red spot later when I wash them.

            Anyone who has put water in their vehicle battery knows the drill. Pull off the caps, fill up to the bottom of the filler neck with distilled water, put the caps back on.

            If I had more batteries I’d hook up a jug with a plastic hose and cutoff so that I could quickly fill. Right now i use a measuring cup (for the spout).

            At half the price you could hire it out…. ;o)

          • vensonata

            Yes, Bob, there are few other considerations. One is that, good watering systems are now available…store bought. That swayed me. But here is one issue: the bulk charge acceptance on flooded lead acid is 10% of the total storage capacity at 20 hours. That means that if you have a forty kwh bank you can not feed in anymore than 4 kwh. on bulk. And it is only a trickle allowed in on the “tapering” charge from 85% full to 100% full, perhaps as little as 1kwh. This means that I would need a 120 kwh battery bank to fully make use of my 12 kwh pv array. Agm on the other hand have a minimum of 35% bulk charge. Therefore I would only need a 40 kwh Agm bank. The trickle charge on Agm is only the last 5% (from 95-100%full)…again a large gain in efficiency. Round trip efficiency loss for wet lead is 11%, for Agm 2%. Also in my two battery banks, the first was wet lead…2001, it lasted 7 years and I had three dud batteries that I needed to replace. Perhaps because of the difficulty in truly balancing the cells. The second set, is AGM, 6 years and nearing the end of life…no duds. In the end because of efficiencies and dud factor plus the sheer size of wet lead bank, the price per kwh is about 25% higher for AGM, but maintenance free. So that is my doctoral dissertation for now Bob.

          • bink

            you have been inquiring what about vanadium for 8 yrs? there are commercially available AVRB’s on the market and based on the prices in this article at less than half the kWh costs, at three times the life cycles and multihour discharge, so what was your question?

          • vensonata

            I’m sold, give me the site.

          • bink

            not selling or promoting on here but truth and credible info and my experience

  • Bob_Wallace

    EOS is claiming 10,000 cycles, 30 year calendar life, and $160/kWh for the system (not just battery).

    ” Eos is can provide peak electricity at a levelized cost of $0.12-0.17 per kWh—substantially less than conventional gas turbines and competing energy storage technologies.”

    (That’s purchasing electricity at off peak prices and full operational costs. IIRC 4 cent wind input would mean 14 cent/kWh dispatchable/peak electricity.)

    http://www.eosenergystorage.com/technology-and-products/

    They are currently being grid evaluated, so we should know something concrete before long.

    • bink

      bob that is not what i was quoted from them 9 months ago and with them having no commercial units i will wait on that one

      • Bob_Wallace

        Fair enough. I’m just copying over what they say on their web site.

        I suppose that within a few months they will have either proven themselves or be forced to withdraw their claims.

        • bink

          understood and without giving the exact number the quote was just for the batteries

          • Bob_Wallace

            ” Eos is can provide peak electricity at a levelized cost of $0.12-0.17 per kWh—substantially less than conventional gas turbines and competing energy storage technologies.”

            That’s total system cost, including electricity purchases, for power coming out of the system.

            This is what they were saying in their video. Purchase electricity at 2c to 5c and sell it back at 12c to 17c.

            Again, their claim. They have not yet provided real world data to back it up. And elsewhere on their site they are stating that current costs are closer to $240/kWh with $160/kWh where they expect to be once they scale up.

            I don’t know if they can do it or at what price. What is encouraging is that they passed the preliminary tests and are getting a real world run on the ConEd grid. I assume that means ConEd thinks their price projections are withing the ballpark.

          • bink

            not really, its called demonstration and it does not consider pricing. I know what it says on the website but what i was quoted for batteries only was above the $240kWh

          • Bob_Wallace

            Yes. And they state, indirectly, that $160/kWh is the price when scaled up.

            What they’re attempting to do now is demonstrate claimed performance. Volume production costs shouldn’t be too hard to estimate.

          • bink

            that does not make it true Bob, as demonstrated by the graves of many before them, By the time they scale up it will be 5 yrs down the road and we will see what the inherent problem with their system is and by the way, ConEdison does not provide 3rd party validation they only provide the test bed others like DOE do that.

          • Bob_Wallace

            No, that does not make it true. But it’s what we have with which to operate.

            You claim that flow batteries will be 8c/kWh? All we have at this point is your statement. We can’t look that up in The Great Book of Facts either.

            We’re outsiders trying to peek in under the curtain.

          • bink

            uh bob, you brought flow into it, not me but I will go there with you. I am not making that statement out of thin air, there is plenty of documentation from DOE supporting that statement plus real quote

          • Bob_Wallace

            Perhaps you gave us that information before but I failed to see/save it. Would you please post it again?

          • kcotte59

            i think the cost for wind/solar power is zero when there is not enough system load to accept it. The value is how much additional non-dispatchable power/energy can be integrated by adding storage and how storage also helps other dispatchable energy resources to be utilized more efficiently. Difficult to calculate but real benefits.

  • Bob_Wallace

    I’m going to post something a bit off topic – think it needs wider distribution..

    “Winfried Hoffmann, a well-known figure throughout the PV world, has created a learning curve for battery storage that predicts costs will fall much faster than many experts believe.”Experts in their own field are often unable to imagine how fast prices can fall,” Winfried Hoffmann of the consulting firm ASE told pv magazine. The former CTO of Applied Materials was one of the pioneers who, at an early stage, analyzed and employed the learning curve for solar modules which has, with hindsight, proved to be accurate.

    Now Hoffmann has applied the same method to the cost trend of lithium-ion battery cells – with equally amazing results, as he outlined in a presentation at this week’s EU PVSEC in Amsterdam. Accordingly, prices for mobile phone batteries have fallen by about 20% in the past when the quantity produced was doubled in watt-hours; car batteries, meanwhile, by about 15% (see Figure 1). On average, a similar value emerges to that of the price experience curve for solar modules. A module that cost US$5-$6 in 2000 costs just $0.50 to $0.60 cents in 2014.

    Both cell phone and lithium-ion car batteries for electric vehicles will, according to Hoffmann’s price experience curve, break the sound barrier of $100 per kilowatt hour (kWh) capacity when batteries with a cumulative capacity of one terawatt hour (tWh) are installed.

    The question is: when will this production volume be achieved? Currently, the cumulative volume for electric car batteries is approximately 7 GWh. With an average annual growth rate of 31%, the cumulative capacity of one tWh will be achieved by 2030. Hoffmann considers this rate to be realistic based on the fact that the cumulative capacity in the solar industry increased on average by 41% between 2000 and 2010. “$100/kWh of storage capacity is therefore possible by 2030,” he says. It can be assumed that prices would fall on average by 7% per year.

    This learning curve applies only to cells. They only become batteries when surrounded by the so-called packaging. If a Lithium-ion car battery cost $520/kWh capacity in 2012, approximately one-third went towards packaging; the rest, about $180, was spent on the production of the cells. By 2020, these packaging costs will, according to an estimate by analysts avicenne, fall to $50, and Hoffmann expects them to fall even further by 2030 by a factor of two.”

    http://www.pv-magazine.com/news/details/beitrag/forecast-2030–stored-electricity-at-005-kwh_100016581/#ixzz3EdmRG6po

    • bink

      this will only make them competitive based on degradation issues

      • Bob_Wallace

        ” based on degradation issues”

        Meaning?

        • bink

          meaning based on the pricing for the system in this article they are twice as expensive as some other technologies so, a price drop for the battery is only an incremental drop for the system and I don’t see system pricing coming down due to inherent degradation issues

          • Bob_Wallace

            bink – you seem to have a lot of information. But you’re not very skilled at getting it across to the sort of audience found on a site like this.

            We are not your peers in the energy/storage industry. We’re relatively smart people from other areas and when there’s too much ‘insider jargon’ stuff just goes over our heads.

            It would be nice if you would put your comments into a form that the average person could understand.

            Taking apart the above comment….

            “twice as expensive as some other technologies” = understandable.

            “a price drop for the battery is only an incremental drop for the system” = sort of understandable. There’s stuff other than the battery in the system – ‘the rest of the pack’. The BoS stuff.

            “don’t see system pricing coming down due to inherent degradation issues” = I still can’t figure out what inherent degradation issues means.

  • UncleB

    This is application of known technologies . . . Will China innovate and realize a new system . . . Where is the old fashioned ingenuity we usually find in American problem solving?

  • Tom Capon

    Of course they put it next to a wind farm because of its “intermittent nature”. Never mind that Germany and Australia are rapidly approaching 50% renewables without any remarkable investment in storage technologies. Truth is even a fossil fuel grid needs battery plants to avoid costly peaker plants and supply ramp-ups. A renewable grid doesn’t need nearly as much storage as people think it does.

    • bink

      Tom, , batteries do a lot more for the grid than discharge energy to the grid. Can you think of anything else?

      • Tom Capon

        Since we’re going Socratic in the comments today… Battery banks can devote 100% of their capacity to grid stability. This will be their primary function until we are phasing out the last of the fossil baseload capacity. Until then, it is the renewables themselves that will be peak shaving and if the fossil generators were smart about how they operate, all the renewable power can go straight to consumers instead of into battery banks.

        • bink

          ow, whose koolaide u been drinking? so u think that batteries dont serve any function but to discharge energy?

          • Tom Capon

            The only two functions of batteries I am aware of are absorbing and releasing energy. (Rapid oxidation is another, but not normally used repeatedly.) The absorption and discharge of energy can of course be timed to have various effects on the grid at large.

            blink, if you know another use for batteries, would you mind sharing with the group so everyone can learn? Thanks.

          • bink

            Tom, besides absorbing energy and discharging it to the grid, energy storage devices are an energy efficiency device, conditions power, provides reactive power and power factoring, black starts, demand response, energy arbitrage, UPS, emergency backup and I see you quickly want to dismiss those effects on the grid but they are important too.

          • Tom Capon

            Did you read my second post? I said the entire function of the battery will be “grid stability”, which in my unenlightened mind meant precisely all those things you listed. I’m sorry you misinterpreted it to mean “energy supply stability” and judged my intelligence based on a misunderstanding.

            But backing up to my original post, I was pointing out that at this point in the grid development, battery plants have no more reason to colocate with wind farms than with FF plants for precisely that reason. We need power conditioning, reactive power, power factor correction, black starts, demand response, and emergency backup EVERYWHERE on the grid.

            A lot of the historical argument against renewables is that they need expensive batteries to function, which is an overblown assumption at least. I was simply pointing out that the placement of this plant at a wind farm was playing into those critics ‘story. But I am sure there were other good reasons for the location, and never questioned the usefulness of the plant to the grid, wherever it is.

          • bink

            listen i am not being specific to where it is being sited , I am talking in general and my reference to storage attributes like energy efficiency, power conditioning etc were a reference to behind the meter commercial and industrial locations not a large centrally located renewable or fossil plant.

            distributed storage can serve peak closer to the load and reduce reserve margins

          • Tom Capon

            I totally agree with everything you have said, now that you actually said it. My entire post was about the merits of this specific location, however, so I was very confused when you started talking about non-location-specific traits.

            Also, while I am now aware of how smart and knowledgeable you are, other people will not know this if you don’t make your actual point in your first post in a thread. If they disagree, they will reply to you, and you can ridicule them then, but I think you will find most often that clearly explaining what you are talking about at the beginning of a thread will result in more positive reactions.

          • bink

            thank you for the compliment and you as well. i am just frustrated by the energy storage industry (manufacturers and vendors) they continue to not be honest about the capability and limitations of their product and we all end up suffering and labeled.

            I know I sound like I am picking on lithium but they are the dominate technology and by the default the worst abusers. I know they are trying to sell batteries and that is all they do, so the intergraters and developers have the lions share of the blame.

            When we are out marketing our system to utilities, the first pushback we get is that energy storage is too expensive but they can never tell you what that is.

            Knowing that the system we market is only commercially available through our supplier and another company who does not have a large presence in the US utility presence we know they must be referring to lithium in most cases.

            articles like this one where we can get real numbers allow us to counteract those objections. We are half on the capex and dropping and lower than half on the kWh costs with further reductions planned.

            So if this is what they are being quoted no wonder the resistance. It is hard to make a business case when people are pushing technology not suitable for certain applications

          • kcotte59

            If they had battery back-up for each of their renewable non-dispatchable resources then they would have something. When you think about it cost-effective storage technology is the only real threat to their business model and they are paying to develop it. Energy storage – you either need it or you don’t. Storage does not produce energy, it eats it up in fact. Waiting for a big cloud on a sunny day combined with another transmission problem to test their reserves.

          • djr417

            I cant tell if your a troll, or someone with something to add to the discussion, but just cant spit it out without coming across as an arrogant jerk.

          • bink

            not a jerk, but i think you have added nothing to this conversation but trying to insult someone who, frankly doesn’t care what you think. I asked a legitimate question and now that he has answered I will respond

          • kcotte59

            When would you charge and discharge these batteries? Charge as the wind/sun power is increasing and discharge when it is decreasing to level out the ramps? Or discharge ahead of expected system load declines so other equipment can begin ramping sooner & ramp slower?
            Should they keep 50% of capacity for emergencies, i.e. system conditions outside of the expected?
            Another words, are the batteries themselves dispatched or do they just do their own thing in the background?

  • Matt

    Some times I wonder if the intent of some of these projects is to show it is too expensive. Like the NetZero home build in the US that cost 2-3X a normal home. They don’t cost that in Europe, or to even build a NetZero office in US. So what gives?

    • Will E

      all prices outprice my calculations.
      I totally agree on what you say.

    • kcotte59

      Inefficiency. Too much cost for administration and overhead. No motivation for employees to perform efficiently, only the opposite.
      Workers (using the word loosely) who are immune to shame, never felt it & never will.

      l

  • vensonata

    Seems a bit pricey per kwh. 50 million dollars divided by 32,000kwh is about $1500 per kw. That includes the building but really that kind of volume should be around $200 kw or 200×32000= 6.4 million dollars. The facility is 6300 sq ft and even at outrageous California prices should not cost more than 6.3 million dollars. So including land, say$2 million, all in all the price should be 15 million, not 50 million. So…what’s up?

    • vensonata

      More math: At 3000 full cycles 32,000kw =96 million kwh, for 50 million dollars. That is over 50cents kwh. Too much, but not terrible for a government science project. But say they had done it for 15 million dollars….15cents/kwh. now you are in the ballpark.

      • bink

        In your first post You need a lot more than more math, you switched from kWh to kW in the same calculation. What are you trying to determine, Capex or kWh costs? 32MWH =32,000 kWh
        $50million / 32,000 kWh = 1562 per kWh not kW. I believe this was an 8MW x4hr battery; 8MW = 8000
        $50million / 8000 = 6250 per kW or Capex

        Very expensive yes, twice the cost of other technologies. Building costs are not great on this (Butler building) and it doesn’t say anything about a land purchase, more than likely did not

      • GCO

        With more shallow cycles, the life of those batteries should be significantly extended. Applications like this can also tolerate much more degradation, further extending battery life.

        We may be close to 15c/kW⋅h already, but what probably matters a whole lot more is, how much spinning reserves this allows to cut.

        • bink

          “Should” is a big word in this instance. Southern Company did a smartgrid demonstration project were the batteries degraded due to ambient temperature operating range and daily discharge of the lithium batteries

          • Bob_Wallace

            Does that simply mean that in the hotter parts of the country battery storage needs to go underground? In building sub-basements, for example.

          • vensonata

            Here is another way to think about this: If they had bought 375 Tesla model S 85 kwh sedans at $80,000 per car they would have a 32 Mwh battery bank. They would have spent 30 million dollars…no building required. Savings of 20 million. Hmmm. Remember, the article said the batteries are the same ones used in the Chevy Volt. Somebody’s budget is padded to the hilt.

          • bink

            you are not going to hook up 375 Tesla and expect to perform ancillary services the whole PC configuration is going to be different and a lot more expensive

          • vensonata

            Hey, bink, I’m only joking about the Tesla’s it would be outrageous… and that’s the point. But two revelations come out of this. Tesla is a moderately expensive 85 kwh battery, but they throw in the car for free. And secondly, this government science project about grid storage lithium deserves some kind of embarrassment prize for unnecessary expense.

          • bink

            as long as you are throwing out embarrassments make sure you include the manufacturers of lithium batteries who are stirring up the Koolaide and the utilities who are drinking it. I am going to give government a pass on this, since they have to investigate until the path to further innovation ends. lithium great for transportation and consumer appliance not so much for grid scale

          • kcotte59

            Good point but this is a one-off custom installation designed for a specific application. A good price comparison none the less, having little else to compare to. Remember that this battery must interface to the grid at high voltage so there will be additional expense for transformer’s, cb’s, and relay protection compared to the Tesla. I’ll take the car though, better warranty. Edison invested only as a show of good faith. And they used your money. Such a facility is most likely more trouble than it is worth for them.

          • Robert Pollock

            That was my thought too. I’ve been driving a Chevy Spark EV for almost a year (6,000 miles). It’s lith-ion 21 kw battery seems to degenerate slightly during the summer, in that a full charge allows 91 to 93 miles. During winter it always charges to 100 to 103 miles. The Spark is the only EV in that category with an active battery cooling system. (Smart cars have something to do with their AC systems, not nearly as effective, and the Leaf has something to, but doesn’t do the job in the real heat)

            Also, SCE is fighting for it’s existence. Those batteries should be deployed in a dozen smaller groups, closer to where the power will be used. The more diversification the better, which is contrary to their “still centralized’ plan. Giant PV farms are a mistake for the same reasons.

          • GCO

            I’ll rephrase then: shallow cycles will extend the life of those batteries, probably significantly.
            I don’t know the exact chemistry used at Tehachapi; for LiFePO4, reducing DoD from 80% to 50% doubles the cycle life. http://www.balqon.com/wp-content/uploads/2013/07/35_35balqon_battery_2013.pdf

            Technology to keep humans, server racks etc comfortable indoor has been available for some time, I see no reason why it couldn’t be applied to this facility.

          • bink

            cycle life on LiFo is very low to began with and in order to do demand response must have 100% dod so that doesn’t help for that application, thus making lithium 1 dimensional (ancillary) and you have to be careful with ambient temperature operating conditions (will degrade battery quickly) if you have to house in building (extra costs)

          • GCO

            You’re not making sense. How exactly would the grid differentiate between a battery bank used at 100% DoD, and another one twice the capacity doing only 50%?
            And what were you suggesting to save the cost of a building around them, however small it is compared to the rest of the setup? Put a big tarp over the whole thing and call it a day?

          • bink

            what kind of sense are you trying to make. what you are suggesting is cost prohibitive that is twice the cost and these batteries in this project are already twice as expensive as other technologies. but a tarp over it, these batteries are subject to degradation due to ambient temperature. total ignorance. Pull down this report, if you dare http://www.smartgridnews.com/artman/publish/Projects_Demo_Pilots/EPRI-Smart-Grid-Demonstration-Update-6781.html

          • GCO

            [Sigh] The installation described here is 3 orders of magnitude larger than the small demo you keep pointing at. A 6300 sq.ft facility, vs a metal box. As per the very report you linked, temperature swings won’t compare.

            Now regarding costs, please tell me which option offers the best bang for the buck: 5k cycles at 50% DoD, or, for the same price, 1k cycles at 100% DoD?
            5x more cycles for 2x the price looks a lot cheaper per cycle, and therefore per kW⋅h, doesn’t it?

          • bink

            if it has problems at a small scale it gets worse as you scale up, but that doesn’t matter the batteries degraded, period. Also, as you saw in the report but refuse to acknowledge partial degradation was attributed to everyday discharge use. I wont acknowledge you because you are ignorant. it costs twice as much because you have to add the additional capacity and like i keep saying they are already more expensive to begin with. if i have a 5kW system that i can discharge 100% vs a 10kW system i can only discharge 50% tell me why the 10kw system is not more expensive if the capex per kw is the same? not only that further degradation will terminate the service contract as well as replace batteries sooner

          • eveee

            Sorry bink. Just wrong. The grid has no idea what the DoD of the battery is. Size it larger, smaller, whatever, .. the grid just sees how many kwhr are delivered at what rate (power) and for how long (power and energy). Just like the grid can’t tell what the source of power and energy is. A LiFe battery can store many times the number of life cycles at lower DoD. That matters to costs. Its very non linear. The result is DoD x cycles x capacity. When cycles goes up way faster than DoD goes down, its a huge advantage to limit discharge. Abusing batteries with deep discharge and overcharging them is a very poor way of using them. Its like under powering a tractor with a weak engine and transmission or powering a huge mechanical load with a weak electric motor. The lifetime is short and the economics miserable. Once sized properly, the source lasts a long time and the economics are favorable. Fail to do that in any of those cases and the system fails. Logically, if not engineering wise, its a straw man.

          • kcotte59

            power dispatchers are trained to do whatever they need to with their resources to keep the system stable Worry about the equipment later. The value of power to a dispatcher is much higher than the price being paid by the user under certain system/market conditions which are dynamic by nature. Linear values for capacity and energy are not applicable to an energy storage facility. They pay for themselves maybe only a few times a year, and on most days they are not producing enough income to pay the interest on the investment. That is why utilities will avoid building them unless forced to by system events or by the regulators, or both.

          • eveee

            All applications are different, even for utilities. Smoothing and regulation are different from load shifting. Batteries for those applications are different. Lithium titanate can withstand deep discharge better and is used there. AES has been supplying those to PHM and they have been in operation for years.

          • eveee

            Right you are, GCO. Here are curves of the number of cycles vs DoD. The upper right graph shows discharge capacity with each curve representing a different DoD. 8000 cycles at 70% or 1000 cycles at 100%. Thats an easy choice.

            http://en.winston-battery.com/index.php/products/power-battery/item/wb-lyp40aha?category_id=176

Back to Top ↑